Add marhun photo webp compression compilers and implementations
This commit is contained in:
afiq.hamzah
@@ -7,6 +7,7 @@ use Illuminate\Support\Facades\Storage;
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use App\Models\FileMarhun;
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use App\Models\LelongBid;
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use Exception;
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use Buglinjo\LaravelWebp\Facades\Webp;
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class MarhunPhotoService
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{
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@@ -14,7 +15,6 @@ class MarhunPhotoService
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public function store(Request $request)
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{
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try {
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$file_type = $request->gambarMarhun->getClientOriginalExtension();
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} catch (Exception $exception) {
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@@ -38,15 +38,27 @@ class MarhunPhotoService
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$photo_type_name = $request->photo_type === '1' ? 'overall_photo' : 'by_marhun_photo';
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$directory = "/{$no_rujukan_sag}/{$photo_type_name}/";
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$imageExtension = $request->file('gambarMarhun')->getClientOriginalExtension();
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$imageExtension = $file_type;
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$marhunImageFileName = "overall";
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$marhunImageFileName = "overall.{$imageExtension}";
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if (!empty($request->lelongbidmarhun_id)) {
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$marhunImageFileName = "$request->lelongbidmarhun_id.$imageExtension";
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$marhunImageFileName = "$request->lelongbidmarhun_id";
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}
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Storage::disk('marhun')->putFileAs($directory, $request->gambarMarhun, $marhunImageFileName);
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Storage::disk('marhun')->putFileAs($directory, $request->gambarMarhun, "${marhunImageFileName}.${imageExtension}");
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$stored_path = Storage::disk('marhun')->path("{$directory}{$marhunImageFileName}.${imageExtension}");
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$convertedFilePath = $this->optimizeImageToWebP($stored_path, $directory, $marhunImageFileName);
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$this->changeFileOwnerToServerUser($convertedFilePath);
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Storage::disk('marhun')->delete("{$directory}${marhunImageFileName}.${imageExtension}");
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$addfile->update([
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'file_type' => 'webp',
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]);
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}
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public function delete(Request $request)
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@@ -109,6 +121,47 @@ class MarhunPhotoService
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}
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return Storage::disk('marhun')->get("{$directory}${marhunImageFileName}");
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}
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private function getWebpCompilerByOS()
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{
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$cwebp_compilers = [
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'Windows' => 'binaries\libwebp-1.2.4-windows-x64\bin\cwebp',
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'Linux' => 'binaries\libwebp-1.2.4-linux-x86-64\bin\cwebp',
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];
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$cwebp_compilers_darwin = [
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'X86-64' => 'binaries\libwebp-1.2.4-mac-X86-64\bin\cwebp',
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'arm64' => 'binaries\libwebp-1.2.4-mac-arm64\bin\cwebp',
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];
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$server_operating_system = explode(' ', trim(php_uname()))[0];
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$server_processor_architecture = trim(php_uname('m'));
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if (in_array($server_operating_system, array_keys($cwebp_compilers))) {
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return resource_path($cwebp_compilers[$server_operating_system]);
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}
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if ($server_operating_system === 'Darwin') {
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return resource_path($cwebp_compilers_darwin[$server_processor_architecture]);
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}
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}
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private function optimizeImageToWebP($originalFilePath, $directory, $lelongbidmarhun_id)
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{
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$convertedFilePath = config('filesystems.disks.marhun.root') . '/' . "{$directory}{$lelongbidmarhun_id}.webp";
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$webpCompiler = $this->getWebpCompilerByOS();
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exec($webpCompiler . ' -q 60 ' . $originalFilePath . ' -o ' . $convertedFilePath);
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return $convertedFilePath;
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}
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private function changeFileOwnerToServerUser($filepath)
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{
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chown($filepath, get_current_user());
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}
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}
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@@ -7,6 +7,7 @@
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"require": {
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"php": "^7.3|^8.0",
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"barryvdh/laravel-dompdf": "^0.9.0",
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"buglinjo/laravel-webp": "^2.3",
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"enlightn/enlightn": "^1.26",
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"fruitcake/laravel-cors": "^2.0",
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"guzzlehttp/guzzle": "^7.4",
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@@ -18,6 +19,7 @@
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"laravelcollective/html": "^6.3",
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"php-http/guzzle7-adapter": "^1.0",
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"pusher/pusher-php-server": "^7.0",
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"spatie/laravel-image-optimizer": "^1.6",
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"spatie/laravel-permission": "^5.3"
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},
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"require-dev": {
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Generated
+190
-2
@@ -4,7 +4,7 @@
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"Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
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||||
"This file is @generated automatically"
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||||
],
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||||
"content-hash": "2f10e37896fbd09e0db3f88edb605951",
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||||
"content-hash": "b693508e783afdca0b77c2e1dcf8217c",
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||||
"packages": [
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||||
{
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||||
"name": "asm89/stack-cors",
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||||
@@ -184,6 +184,71 @@
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],
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"time": "2021-08-15T20:50:18+00:00"
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},
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{
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"name": "buglinjo/laravel-webp",
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"version": "v2.3.1",
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"source": {
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||||
"type": "git",
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||||
"url": "https://github.com/buglinjo/laravel-webp.git",
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||||
"reference": "8d28bad5dbb82d7257eb77f27b5c57daa0c0d6b8"
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||||
},
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||||
"dist": {
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||||
"type": "zip",
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||||
"url": "https://api.github.com/repos/buglinjo/laravel-webp/zipball/8d28bad5dbb82d7257eb77f27b5c57daa0c0d6b8",
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||||
"reference": "8d28bad5dbb82d7257eb77f27b5c57daa0c0d6b8",
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||||
"shasum": ""
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||||
},
|
||||
"require": {
|
||||
"ext-gd": "*",
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||||
"laravel/framework": "~5.1|~6.0|~7.0|~8.0|~9.0",
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"php": "^7.1|^8.0|^8.1"
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||||
},
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||||
"require-dev": {
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||||
"phpunit/phpunit": ">=5.4.3",
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||||
"squizlabs/php_codesniffer": "^2.3|^3.6"
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||||
},
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||||
"type": "library",
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||||
"extra": {
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||||
"laravel": {
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"providers": [
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"Buglinjo\\LaravelWebp\\WebpServiceProvider"
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],
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"aliases": {
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"Webp": "Buglinjo\\LaravelWebp\\Webp"
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}
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||||
}
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||||
},
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||||
"autoload": {
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||||
"psr-4": {
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||||
"Buglinjo\\LaravelWebp\\": "src"
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||||
}
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||||
},
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||||
"notification-url": "https://packagist.org/downloads/",
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||||
"license": [
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||||
"MIT"
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||||
],
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||||
"authors": [
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||||
{
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||||
"name": "Irakli Tchitadze",
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||||
"email": "irakli.tchitadze@gmail.com",
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||||
"homepage": "https://irakli.dev",
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||||
"role": "Developer"
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||||
}
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||||
],
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||||
"description": "Laravel package for WebP image formatting.",
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"homepage": "https://github.com/buglinjo/laravel-webp",
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"keywords": [
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"Buglinjo",
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||||
"LaravelWebp",
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||||
"Webp",
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||||
"laravel"
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||||
],
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"support": {
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||||
"issues": "https://github.com/buglinjo/laravel-webp/issues",
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||||
"source": "https://github.com/buglinjo/laravel-webp/tree/v2.3.1"
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||||
},
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||||
"time": "2022-03-15T01:49:23+00:00"
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||||
},
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||||
{
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||||
"name": "clue/stream-filter",
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||||
"version": "v1.6.0",
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@@ -5760,6 +5825,129 @@
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||||
],
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"time": "2022-07-20T18:31:45+00:00"
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||||
},
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||||
{
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||||
"name": "spatie/image-optimizer",
|
||||
"version": "1.6.2",
|
||||
"source": {
|
||||
"type": "git",
|
||||
"url": "https://github.com/spatie/image-optimizer.git",
|
||||
"reference": "6db75529cbf8fa84117046a9d513f277aead90a0"
|
||||
},
|
||||
"dist": {
|
||||
"type": "zip",
|
||||
"url": "https://api.github.com/repos/spatie/image-optimizer/zipball/6db75529cbf8fa84117046a9d513f277aead90a0",
|
||||
"reference": "6db75529cbf8fa84117046a9d513f277aead90a0",
|
||||
"shasum": ""
|
||||
},
|
||||
"require": {
|
||||
"ext-fileinfo": "*",
|
||||
"php": "^7.3|^8.0",
|
||||
"psr/log": "^1.0 | ^2.0 | ^3.0",
|
||||
"symfony/process": "^4.2|^5.0|^6.0"
|
||||
},
|
||||
"require-dev": {
|
||||
"phpunit/phpunit": "^8.5.21|^9.4.4",
|
||||
"symfony/var-dumper": "^4.2|^5.0|^6.0"
|
||||
},
|
||||
"type": "library",
|
||||
"autoload": {
|
||||
"psr-4": {
|
||||
"Spatie\\ImageOptimizer\\": "src"
|
||||
}
|
||||
},
|
||||
"notification-url": "https://packagist.org/downloads/",
|
||||
"license": [
|
||||
"MIT"
|
||||
],
|
||||
"authors": [
|
||||
{
|
||||
"name": "Freek Van der Herten",
|
||||
"email": "freek@spatie.be",
|
||||
"homepage": "https://spatie.be",
|
||||
"role": "Developer"
|
||||
}
|
||||
],
|
||||
"description": "Easily optimize images using PHP",
|
||||
"homepage": "https://github.com/spatie/image-optimizer",
|
||||
"keywords": [
|
||||
"image-optimizer",
|
||||
"spatie"
|
||||
],
|
||||
"support": {
|
||||
"issues": "https://github.com/spatie/image-optimizer/issues",
|
||||
"source": "https://github.com/spatie/image-optimizer/tree/1.6.2"
|
||||
},
|
||||
"time": "2021-12-21T10:08:05+00:00"
|
||||
},
|
||||
{
|
||||
"name": "spatie/laravel-image-optimizer",
|
||||
"version": "1.6.4",
|
||||
"source": {
|
||||
"type": "git",
|
||||
"url": "https://github.com/spatie/laravel-image-optimizer.git",
|
||||
"reference": "c39e9ea77dee6b6eddfc26800adb1aa06a624294"
|
||||
},
|
||||
"dist": {
|
||||
"type": "zip",
|
||||
"url": "https://api.github.com/repos/spatie/laravel-image-optimizer/zipball/c39e9ea77dee6b6eddfc26800adb1aa06a624294",
|
||||
"reference": "c39e9ea77dee6b6eddfc26800adb1aa06a624294",
|
||||
"shasum": ""
|
||||
},
|
||||
"require": {
|
||||
"laravel/framework": "^6.0|^7.0|^8.0",
|
||||
"php": "^7.2|^8.0",
|
||||
"spatie/image-optimizer": "^1.2.0"
|
||||
},
|
||||
"require-dev": {
|
||||
"orchestra/testbench": "^4.0|^5.0|^6.0",
|
||||
"phpunit/phpunit": "^9.0"
|
||||
},
|
||||
"type": "library",
|
||||
"extra": {
|
||||
"laravel": {
|
||||
"providers": [
|
||||
"Spatie\\LaravelImageOptimizer\\ImageOptimizerServiceProvider"
|
||||
],
|
||||
"aliases": {
|
||||
"ImageOptimizer": "Spatie\\LaravelImageOptimizer\\Facades\\ImageOptimizer"
|
||||
}
|
||||
}
|
||||
},
|
||||
"autoload": {
|
||||
"psr-4": {
|
||||
"Spatie\\LaravelImageOptimizer\\": "src"
|
||||
}
|
||||
},
|
||||
"notification-url": "https://packagist.org/downloads/",
|
||||
"license": [
|
||||
"MIT"
|
||||
],
|
||||
"authors": [
|
||||
{
|
||||
"name": "Freek Van der Herten",
|
||||
"email": "freek@spatie.be",
|
||||
"homepage": "https://spatie.be",
|
||||
"role": "Developer"
|
||||
}
|
||||
],
|
||||
"description": "Optimize images in your Laravel app",
|
||||
"homepage": "https://github.com/spatie/laravel-image-optimizer",
|
||||
"keywords": [
|
||||
"laravel-image-optimizer",
|
||||
"spatie"
|
||||
],
|
||||
"support": {
|
||||
"issues": "https://github.com/spatie/laravel-image-optimizer/issues",
|
||||
"source": "https://github.com/spatie/laravel-image-optimizer/tree/1.6.4"
|
||||
},
|
||||
"funding": [
|
||||
{
|
||||
"url": "https://spatie.be/open-source/support-us",
|
||||
"type": "custom"
|
||||
}
|
||||
],
|
||||
"time": "2020-11-27T18:27:06+00:00"
|
||||
},
|
||||
{
|
||||
"name": "spatie/laravel-permission",
|
||||
"version": "5.5.16",
|
||||
@@ -10786,5 +10974,5 @@
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"php": "^7.3|^8.0"
|
||||
},
|
||||
"platform-dev": [],
|
||||
"plugin-api-version": "1.1.0"
|
||||
"plugin-api-version": "2.0.0"
|
||||
}
|
||||
|
||||
+9
-9
@@ -61,15 +61,15 @@ return [
|
||||
'options' => extension_loaded('pdo_mysql') ? array_filter([
|
||||
PDO::MYSQL_ATTR_SSL_CA => env('MYSQL_ATTR_SSL_CA'),
|
||||
]) : [],
|
||||
// 'modes' => [
|
||||
// //'ONLY_FULL_GROUP_BY', // Disable this to allow grouping by one column
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||||
// 'STRICT_TRANS_TABLES',
|
||||
// 'NO_ZERO_IN_DATE',
|
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// 'NO_ZERO_DATE',
|
||||
// 'ERROR_FOR_DIVISION_BY_ZERO',
|
||||
// 'NO_AUTO_CREATE_USER',
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||||
// 'NO_ENGINE_SUBSTITUTION'
|
||||
// ],
|
||||
'modes' => [
|
||||
//'ONLY_FULL_GROUP_BY', // Disable this to allow grouping by one column
|
||||
'STRICT_TRANS_TABLES',
|
||||
'NO_ZERO_IN_DATE',
|
||||
'NO_ZERO_DATE',
|
||||
'ERROR_FOR_DIVISION_BY_ZERO',
|
||||
'NO_AUTO_CREATE_USER',
|
||||
'NO_ENGINE_SUBSTITUTION'
|
||||
],
|
||||
|
||||
],
|
||||
|
||||
|
||||
@@ -0,0 +1,29 @@
|
||||
# How to Contribute
|
||||
|
||||
We'd love to accept your patches and contributions to this project. There are
|
||||
just a few small guidelines you need to follow.
|
||||
|
||||
## Contributor License Agreement
|
||||
|
||||
Contributions to this project must be accompanied by a Contributor License
|
||||
Agreement. You (or your employer) retain the copyright to your contribution;
|
||||
this simply gives us permission to use and redistribute your contributions as
|
||||
part of the project. Head over to <https://cla.developers.google.com/> to see
|
||||
your current agreements on file or to sign a new one.
|
||||
|
||||
You generally only need to submit a CLA once, so if you've already submitted one
|
||||
(even if it was for a different project), you probably don't need to do it
|
||||
again.
|
||||
|
||||
## Code reviews
|
||||
|
||||
All submissions, including submissions by project members, require review. We
|
||||
use a [Gerrit](https://www.gerritcodereview.com) instance hosted at
|
||||
https://chromium-review.googlesource.com for this purpose. See the
|
||||
[WebM Project page](https://www.webmproject.org/code/contribute/submitting-patches/)
|
||||
for additional details.
|
||||
|
||||
## Community Guidelines
|
||||
|
||||
This project follows
|
||||
[Google's Open Source Community Guidelines](https://opensource.google.com/conduct/).
|
||||
@@ -0,0 +1,65 @@
|
||||
# WebP Codec
|
||||
|
||||
```
|
||||
__ __ ____ ____ ____
|
||||
/ \\/ \/ _ \/ _ )/ _ \
|
||||
\ / __/ _ \ __/
|
||||
\__\__/\____/\_____/__/ ____ ___
|
||||
/ _/ / \ \ / _ \/ _/
|
||||
/ \_/ / / \ \ __/ \__
|
||||
\____/____/\_____/_____/____/v1.2.4
|
||||
```
|
||||
|
||||
WebP codec is a library to encode and decode images in WebP format. This package
|
||||
contains the library that can be used in other programs to add WebP support, as
|
||||
well as the command line tools 'cwebp' and 'dwebp' to compress and decompress
|
||||
images respectively.
|
||||
|
||||
See https://developers.google.com/speed/webp for details on the image format.
|
||||
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp
|
||||
|
||||
It is released under the same license as the WebM project. See
|
||||
https://www.webmproject.org/license/software/ or the "COPYING" file for details.
|
||||
An additional intellectual property rights grant can be found in the file
|
||||
PATENTS.
|
||||
|
||||
## Files
|
||||
|
||||
* bin/cwebp : encoding tool
|
||||
* bin/dwebp : decoding tool
|
||||
* bin/gif2webp : gif conversion tool
|
||||
* bin/img2webp : animation creation tool
|
||||
* bin/vwebp : webp visualization tool
|
||||
* bin/webpinfo : webp analysis tool
|
||||
* bin/webpmux : webp muxing tool
|
||||
* bin/anim\_diff : webp file comparison tool
|
||||
* bin/anim\_dump : tool for dumping animation frames
|
||||
* bin/get\_disto : tool for calculating file distortion
|
||||
* bin/webp\_quality : webp quality estimation tool
|
||||
* doc/ : manual in HTML and text formats
|
||||
* lib/ : static libraries
|
||||
* include/webp : headers
|
||||
|
||||
## Encoding and Decoding Tools
|
||||
|
||||
The bin/ directory contains tools to encode and decode images and animations,
|
||||
view information about WebP images, and more. See the
|
||||
[tools documentation](doc/tools.md).
|
||||
|
||||
## APIs
|
||||
|
||||
See the [APIs documentation](doc/api.md).
|
||||
|
||||
## Bugs
|
||||
|
||||
Please report all bugs to the issue tracker: https://bugs.chromium.org/p/webp
|
||||
|
||||
Patches welcome! See [how to contribute](CONTRIBUTING.md).
|
||||
|
||||
## Discuss
|
||||
|
||||
Email: webp-discuss@webmproject.org
|
||||
|
||||
Web: https://groups.google.com/a/webmproject.org/group/webp-discuss
|
||||
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@@ -0,0 +1,385 @@
|
||||
# WebP APIs
|
||||
|
||||
## Encoding API
|
||||
|
||||
The main encoding functions are available in the header src/webp/encode.h
|
||||
|
||||
The ready-to-use ones are:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
```
|
||||
|
||||
They will convert raw RGB samples to a WebP data. The only control supplied is
|
||||
the quality factor.
|
||||
|
||||
There are some variants for using the lossless format:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
```
|
||||
|
||||
Of course in this case, no quality factor is needed since the compression occurs
|
||||
without loss of the input values, at the expense of larger output sizes.
|
||||
|
||||
### Advanced encoding API
|
||||
|
||||
A more advanced API is based on the WebPConfig and WebPPicture structures.
|
||||
|
||||
WebPConfig contains the encoding settings and is not tied to a particular
|
||||
picture. WebPPicture contains input data, on which some WebPConfig will be used
|
||||
for compression. The encoding flow looks like:
|
||||
|
||||
```c
|
||||
#include <webp/encode.h>
|
||||
|
||||
// Setup a config, starting form a preset and tuning some additional
|
||||
// parameters
|
||||
WebPConfig config;
|
||||
if (!WebPConfigPreset(&config, WEBP_PRESET_PHOTO, quality_factor)) {
|
||||
return 0; // version error
|
||||
}
|
||||
// ... additional tuning
|
||||
config.sns_strength = 90;
|
||||
config.filter_sharpness = 6;
|
||||
config_error = WebPValidateConfig(&config); // not mandatory, but useful
|
||||
|
||||
// Setup the input data
|
||||
WebPPicture pic;
|
||||
if (!WebPPictureInit(&pic)) {
|
||||
return 0; // version error
|
||||
}
|
||||
pic.width = width;
|
||||
pic.height = height;
|
||||
// allocated picture of dimension width x height
|
||||
if (!WebPPictureAlloc(&pic)) {
|
||||
return 0; // memory error
|
||||
}
|
||||
// at this point, 'pic' has been initialized as a container,
|
||||
// and can receive the Y/U/V samples.
|
||||
// Alternatively, one could use ready-made import functions like
|
||||
// WebPPictureImportRGB(), which will take care of memory allocation.
|
||||
// In any case, past this point, one will have to call
|
||||
// WebPPictureFree(&pic) to reclaim memory.
|
||||
|
||||
// Set up a byte-output write method. WebPMemoryWriter, for instance.
|
||||
WebPMemoryWriter wrt;
|
||||
WebPMemoryWriterInit(&wrt); // initialize 'wrt'
|
||||
|
||||
pic.writer = MyFileWriter;
|
||||
pic.custom_ptr = my_opaque_structure_to_make_MyFileWriter_work;
|
||||
|
||||
// Compress!
|
||||
int ok = WebPEncode(&config, &pic); // ok = 0 => error occurred!
|
||||
WebPPictureFree(&pic); // must be called independently of the 'ok' result.
|
||||
|
||||
// output data should have been handled by the writer at that point.
|
||||
// -> compressed data is the memory buffer described by wrt.mem / wrt.size
|
||||
|
||||
// deallocate the memory used by compressed data
|
||||
WebPMemoryWriterClear(&wrt);
|
||||
```
|
||||
|
||||
## Decoding API
|
||||
|
||||
This is mainly just one function to call:
|
||||
|
||||
```c
|
||||
#include "webp/decode.h"
|
||||
uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
Please have a look at the file src/webp/decode.h for the details. There are
|
||||
variants for decoding in BGR/RGBA/ARGB/BGRA order, along with decoding to raw
|
||||
Y'CbCr samples. One can also decode the image directly into a pre-allocated
|
||||
buffer.
|
||||
|
||||
To detect a WebP file and gather the picture's dimensions, the function:
|
||||
|
||||
```c
|
||||
int WebPGetInfo(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
is supplied. No decoding is involved when using it.
|
||||
|
||||
### Incremental decoding API
|
||||
|
||||
In the case when data is being progressively transmitted, pictures can still be
|
||||
incrementally decoded using a slightly more complicated API. Decoder state is
|
||||
stored into an instance of the WebPIDecoder object. This object can be created
|
||||
with the purpose of decoding either RGB or Y'CbCr samples. For instance:
|
||||
|
||||
```c
|
||||
WebPDecBuffer buffer;
|
||||
WebPInitDecBuffer(&buffer);
|
||||
buffer.colorspace = MODE_BGR;
|
||||
...
|
||||
WebPIDecoder* idec = WebPINewDecoder(&buffer);
|
||||
```
|
||||
|
||||
As data is made progressively available, this incremental-decoder object can be
|
||||
used to decode the picture further. There are two (mutually exclusive) ways to
|
||||
pass freshly arrived data:
|
||||
|
||||
either by appending the fresh bytes:
|
||||
|
||||
```c
|
||||
WebPIAppend(idec, fresh_data, size_of_fresh_data);
|
||||
```
|
||||
|
||||
or by just mentioning the new size of the transmitted data:
|
||||
|
||||
```c
|
||||
WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
|
||||
```
|
||||
|
||||
Note that 'buffer' can be modified between each call to WebPIUpdate, in
|
||||
particular when the buffer is resized to accommodate larger data.
|
||||
|
||||
These functions will return the decoding status: either VP8_STATUS_SUSPENDED if
|
||||
decoding is not finished yet or VP8_STATUS_OK when decoding is done. Any other
|
||||
status is an error condition.
|
||||
|
||||
The 'idec' object must always be released (even upon an error condition) by
|
||||
calling: WebPDelete(idec).
|
||||
|
||||
To retrieve partially decoded picture samples, one must use the corresponding
|
||||
method: WebPIDecGetRGB or WebPIDecGetYUVA. It will return the last displayable
|
||||
pixel row.
|
||||
|
||||
Lastly, note that decoding can also be performed into a pre-allocated pixel
|
||||
buffer. This buffer must be passed when creating a WebPIDecoder, calling
|
||||
WebPINewRGB() or WebPINewYUVA().
|
||||
|
||||
Please have a look at the src/webp/decode.h header for further details.
|
||||
|
||||
### Advanced Decoding API
|
||||
|
||||
WebP decoding supports an advanced API which provides on-the-fly cropping and
|
||||
rescaling, something of great usefulness on memory-constrained environments like
|
||||
mobile phones. Basically, the memory usage will scale with the output's size,
|
||||
not the input's, when one only needs a quick preview or a zoomed in portion of
|
||||
an otherwise too-large picture. Some CPU can be saved too, incidentally.
|
||||
|
||||
```c
|
||||
// A) Init a configuration object
|
||||
WebPDecoderConfig config;
|
||||
CHECK(WebPInitDecoderConfig(&config));
|
||||
|
||||
// B) optional: retrieve the bitstream's features.
|
||||
CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
|
||||
|
||||
// C) Adjust 'config' options, if needed
|
||||
config.options.no_fancy_upsampling = 1;
|
||||
config.options.use_scaling = 1;
|
||||
config.options.scaled_width = scaledWidth();
|
||||
config.options.scaled_height = scaledHeight();
|
||||
// etc.
|
||||
|
||||
// D) Specify 'config' output options for specifying output colorspace.
|
||||
// Optionally the external image decode buffer can also be specified.
|
||||
config.output.colorspace = MODE_BGRA;
|
||||
// Optionally, the config.output can be pointed to an external buffer as
|
||||
// well for decoding the image. This externally supplied memory buffer
|
||||
// should be big enough to store the decoded picture.
|
||||
config.output.u.RGBA.rgba = (uint8_t*) memory_buffer;
|
||||
config.output.u.RGBA.stride = scanline_stride;
|
||||
config.output.u.RGBA.size = total_size_of_the_memory_buffer;
|
||||
config.output.is_external_memory = 1;
|
||||
|
||||
// E) Decode the WebP image. There are two variants w.r.t decoding image.
|
||||
// The first one (E.1) decodes the full image and the second one (E.2) is
|
||||
// used to incrementally decode the image using small input buffers.
|
||||
// Any one of these steps can be used to decode the WebP image.
|
||||
|
||||
// E.1) Decode full image.
|
||||
CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
|
||||
|
||||
// E.2) Decode image incrementally.
|
||||
WebPIDecoder* const idec = WebPIDecode(NULL, NULL, &config);
|
||||
CHECK(idec != NULL);
|
||||
while (bytes_remaining > 0) {
|
||||
VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
|
||||
if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
|
||||
bytes_remaining -= bytes_read;
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
WebPIDelete(idec);
|
||||
|
||||
// F) Decoded image is now in config.output (and config.output.u.RGBA).
|
||||
// It can be saved, displayed or otherwise processed.
|
||||
|
||||
// G) Reclaim memory allocated in config's object. It's safe to call
|
||||
// this function even if the memory is external and wasn't allocated
|
||||
// by WebPDecode().
|
||||
WebPFreeDecBuffer(&config.output);
|
||||
```
|
||||
|
||||
## Webp Mux
|
||||
|
||||
WebPMux is a set of two libraries 'Mux' and 'Demux' for creation, extraction and
|
||||
manipulation of an extended format WebP file, which can have features like color
|
||||
profile, metadata and animation. Reference command-line tools `webpmux` and
|
||||
`vwebp` as well as the WebP container specification
|
||||
'doc/webp-container-spec.txt' are also provided in this package, see the
|
||||
[tools documentation](tools.md).
|
||||
|
||||
### Mux API
|
||||
|
||||
The Mux API contains methods for adding data to and reading data from WebP
|
||||
files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
|
||||
Other features may be added in subsequent releases.
|
||||
|
||||
Example#1 (pseudo code): Creating a WebPMux object with image data, color
|
||||
profile and XMP metadata.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
WebPMux* mux = WebPMuxNew();
|
||||
// ... (Prepare image data).
|
||||
WebPMuxSetImage(mux, &image, copy_data);
|
||||
// ... (Prepare ICC profile data).
|
||||
WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
|
||||
// ... (Prepare XMP metadata).
|
||||
WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
|
||||
// Get data from mux in WebP RIFF format.
|
||||
WebPMuxAssemble(mux, &output_data);
|
||||
WebPMuxDelete(mux);
|
||||
// ... (Consume output_data; e.g. write output_data.bytes to file).
|
||||
WebPDataClear(&output_data);
|
||||
```
|
||||
|
||||
Example#2 (pseudo code): Get image and color profile data from a WebP file.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
// ... (Read data from file).
|
||||
WebPMux* mux = WebPMuxCreate(&data, copy_data);
|
||||
WebPMuxGetFrame(mux, 1, &image);
|
||||
// ... (Consume image; e.g. call WebPDecode() to decode the data).
|
||||
WebPMuxGetChunk(mux, "ICCP", &icc_profile);
|
||||
// ... (Consume icc_profile).
|
||||
WebPMuxDelete(mux);
|
||||
free(data);
|
||||
```
|
||||
|
||||
For a detailed Mux API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
### Demux API
|
||||
|
||||
The Demux API enables extraction of images and extended format data from WebP
|
||||
files. This API currently supports reading of XMP/EXIF metadata, ICC profile and
|
||||
animated images. Other features may be added in subsequent releases.
|
||||
|
||||
Code example: Demuxing WebP data to extract all the frames, ICC profile and
|
||||
EXIF/XMP metadata.
|
||||
|
||||
```c
|
||||
WebPDemuxer* demux = WebPDemux(&webp_data);
|
||||
uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
|
||||
uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
|
||||
// ... (Get information about the features present in the WebP file).
|
||||
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
|
||||
|
||||
// ... (Iterate over all frames).
|
||||
WebPIterator iter;
|
||||
if (WebPDemuxGetFrame(demux, 1, &iter)) {
|
||||
do {
|
||||
// ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
|
||||
// ... and get other frame properties like width, height, offsets etc.
|
||||
// ... see 'struct WebPIterator' below for more info).
|
||||
} while (WebPDemuxNextFrame(&iter));
|
||||
WebPDemuxReleaseIterator(&iter);
|
||||
}
|
||||
|
||||
// ... (Extract metadata).
|
||||
WebPChunkIterator chunk_iter;
|
||||
if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
|
||||
// ... (Consume the ICC profile in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
|
||||
// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
|
||||
// ... (Consume the XMP metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
WebPDemuxDelete(demux);
|
||||
```
|
||||
|
||||
For a detailed Demux API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
|
||||
## AnimEncoder API
|
||||
|
||||
The AnimEncoder API can be used to create animated WebP images.
|
||||
|
||||
Code example:
|
||||
|
||||
```c
|
||||
WebPAnimEncoderOptions enc_options;
|
||||
WebPAnimEncoderOptionsInit(&enc_options);
|
||||
// ... (Tune 'enc_options' as needed).
|
||||
WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
|
||||
while(<there are more frames>) {
|
||||
WebPConfig config;
|
||||
WebPConfigInit(&config);
|
||||
// ... (Tune 'config' as needed).
|
||||
WebPAnimEncoderAdd(enc, frame, duration, &config);
|
||||
}
|
||||
WebPAnimEncoderAssemble(enc, webp_data);
|
||||
WebPAnimEncoderDelete(enc);
|
||||
// ... (Write the 'webp_data' to a file, or re-mux it further).
|
||||
```
|
||||
|
||||
For a detailed AnimEncoder API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
## AnimDecoder API
|
||||
|
||||
This AnimDecoder API allows decoding (possibly) animated WebP images.
|
||||
|
||||
Code Example:
|
||||
|
||||
```c
|
||||
WebPAnimDecoderOptions dec_options;
|
||||
WebPAnimDecoderOptionsInit(&dec_options);
|
||||
// Tune 'dec_options' as needed.
|
||||
WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
|
||||
WebPAnimInfo anim_info;
|
||||
WebPAnimDecoderGetInfo(dec, &anim_info);
|
||||
for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
|
||||
while (WebPAnimDecoderHasMoreFrames(dec)) {
|
||||
uint8_t* buf;
|
||||
int timestamp;
|
||||
WebPAnimDecoderGetNext(dec, &buf, ×tamp);
|
||||
// ... (Render 'buf' based on 'timestamp').
|
||||
// ... (Do NOT free 'buf', as it is owned by 'dec').
|
||||
}
|
||||
WebPAnimDecoderReset(dec);
|
||||
}
|
||||
const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
|
||||
// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
|
||||
WebPAnimDecoderDelete(dec);
|
||||
```
|
||||
|
||||
For a detailed AnimDecoder API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
@@ -0,0 +1,635 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>CWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">CWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp -
|
||||
compress an image file to a WebP file</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
[<i>options</i>] <i>input_file -o output_file.webp</i></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>cwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
compresses an image using the WebP format. Input format can
|
||||
be either PNG, JPEG, TIFF, WebP or raw Y’CbCr samples.
|
||||
Note: Animated PNG and WebP files are not supported.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
-o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>cwebp</b> will perform compression
|
||||
but only report statistics. Using "-" as output
|
||||
name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>--</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with a
|
||||
’-’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be
|
||||
ignored.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-h, -help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-H, -longhelp</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A summary of all the possible
|
||||
options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-lossless</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode the image without any
|
||||
loss. For images with fully transparent area, the invisible
|
||||
pixel values (R/G/B or Y/U/V) will be preserved only if the
|
||||
-exact option is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-near_lossless</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the level of
|
||||
near-lossless image preprocessing. This option adjusts pixel
|
||||
values to help compressibility, but has minimal impact on
|
||||
the visual quality. It triggers lossless compression mode
|
||||
automatically. The range is 0 (maximum preprocessing) to 100
|
||||
(no preprocessing, the default). The typical value is around
|
||||
60. Note that lossy with <b>-q 100</b> can at times yield
|
||||
better results.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-q</b> <i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossy compression (default), a small factor
|
||||
produces a smaller file with lower quality. Best quality is
|
||||
achieved by using a value of 100. <br>
|
||||
In case of lossless compression (specified by the
|
||||
<b>-lossless</b> option), a small factor enables faster
|
||||
compression speed, but produces a larger file. Maximum
|
||||
compression is achieved by using a value of 100.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-z</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Switch on <b>lossless</b> compression mode with the
|
||||
specified level between 0 and 9, with level 0 being the
|
||||
fastest, 9 being the slowest. Fast mode produces larger file
|
||||
size than slower ones. A good default is <b>-z 6</b>. This
|
||||
option is actually a shortcut for some predefined settings
|
||||
for quality and method. If options <b>-q</b> or <b>-m</b>
|
||||
are subsequently used, they will invalidate the effect of
|
||||
this option.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-alpha_q</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for alpha compression between 0 and 100. Lossless
|
||||
compression of alpha is achieved using a value of 100, while
|
||||
the lower values result in a lossy compression. The default
|
||||
is 100.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-preset</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a set of pre-defined
|
||||
parameters to suit a particular type of source material.
|
||||
Possible values are: <b>default</b>, <b>photo</b>,
|
||||
<b>picture</b>, <b>drawing</b>, <b>icon</b>, <b>text</b>.
|
||||
Since <b>-preset</b> overwrites the other parameters’
|
||||
values (except the <b>-q</b> one), this option should
|
||||
preferably appear first in the order of the arguments.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-m</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Specify the compression method to use. This parameter
|
||||
controls the trade off between encoding speed and the
|
||||
compressed file size and quality. Possible values range from
|
||||
0 to 6. Default value is 4. When higher values are used, the
|
||||
encoder will spend more time inspecting additional encoding
|
||||
possibilities and decide on the quality gain. Lower value
|
||||
can result in faster processing time at the expense of
|
||||
larger file size and lower compression quality.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-crop</b> <i>x_position
|
||||
y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the source to a rectangle
|
||||
with top-left corner at coordinates (<b>x_position</b>,
|
||||
<b>y_position</b>) and size <b>width</b> x <b>height</b>.
|
||||
This cropping area must be fully contained within the source
|
||||
rectangle. Note: the cropping is applied <i>before</i> any
|
||||
scaling.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-resize</b> <i>width
|
||||
height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Resize the source to a
|
||||
rectangle with size <b>width</b> x <b>height</b>. If either
|
||||
(but not both) of the <b>width</b> or <b>height</b>
|
||||
parameters is 0, the value will be calculated preserving the
|
||||
aspect-ratio. Note: scaling is applied <i>after</i>
|
||||
cropping.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>-mt</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p>Use multi-threading for encoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-low_memory</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Reduce memory usage of lossy
|
||||
encoding by saving four times the compressed size
|
||||
(typically). This will make the encoding slower and the
|
||||
output slightly different in size and distortion. This flag
|
||||
is only effective for methods 3 and up, and is off by
|
||||
default. Note that leaving this flag off will have some side
|
||||
effects on the bitstream: it forces certain bitstream
|
||||
features like number of partitions (forced to 1). Note that
|
||||
a more detailed report of bitstream size is printed by
|
||||
<b>cwebp</b> when using this option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOSSY
|
||||
OPTIONS</b> <br>
|
||||
These options are only effective when doing lossy encoding
|
||||
(the default, with or without alpha). <b><br>
|
||||
-size</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target size (in
|
||||
bytes) to try and reach for the compressed output. The
|
||||
compressor will make several passes of partial encoding in
|
||||
order to get as close as possible to this target. If both
|
||||
<b>-size</b> and <b>-psnr</b> are used, <b>-size</b> value
|
||||
will prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-psnr</b> <i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target PSNR (in dB)
|
||||
to try and reach for the compressed output. The compressor
|
||||
will make several passes of partial encoding in order to get
|
||||
as close as possible to this target. If both <b>-size</b>
|
||||
and <b>-psnr</b> are used, <b>-size</b> value will
|
||||
prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-pass</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set a maximum number of passes
|
||||
to use during the dichotomy used by options <b>-size</b> or
|
||||
<b>-psnr</b>. Maximum value is 10, default is 1. If options
|
||||
<b>-size</b> or <b>-psnr</b> were used, but <b>-pass</b>
|
||||
wasn’t specified, a default value of ’6’
|
||||
passes will be used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-qrange</b> <i>int
|
||||
int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specifies the permissible
|
||||
interval for the quality factor. This is particularly useful
|
||||
when using multi-pass (<b>-size</b> or <b>-psnr</b>
|
||||
options). Default is 0 100. If the quality factor is outside
|
||||
this range, it will be clamped. If the minimum value must be
|
||||
less or equal to the maximum one.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>-af</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Turns auto-filter on. This algorithm will spend
|
||||
additional time optimizing the filtering strength to reach a
|
||||
well-balanced quality.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-jpeg_like</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the internal parameter
|
||||
mapping to better match the expected size of JPEG
|
||||
compression. This flag will generally produce an output file
|
||||
of similar size to its JPEG equivalent (for the same
|
||||
<b>-q</b> setting), but with less visual distortion.</p>
|
||||
|
||||
<p style="margin-left:11%;">Advanced options:</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-f</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Specify the strength of the deblocking filter, between 0
|
||||
(no filtering) and 100 (maximum filtering). A value of 0
|
||||
will turn off any filtering. Higher value will increase the
|
||||
strength of the filtering process applied after decoding the
|
||||
picture. The higher the value the smoother the picture will
|
||||
appear. Typical values are usually in the range of 20 to
|
||||
50.</p> </td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-sharpness</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the sharpness of the
|
||||
filtering (if used). Range is 0 (sharpest) to 7 (least
|
||||
sharp). Default is 0.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-strong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use strong filtering (if
|
||||
filtering is being used thanks to the <b>-f</b> option).
|
||||
Strong filtering is on by default.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nostrong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable strong filtering (if
|
||||
filtering is being used thanks to the <b>-f</b> option) and
|
||||
use simple filtering instead.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-sharp_yuv</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use more accurate and sharper
|
||||
RGB->YUV conversion if needed. Note that this process is
|
||||
slower than the default ’fast’ RGB->YUV
|
||||
conversion.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-sns</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the amplitude of the
|
||||
spatial noise shaping. Spatial noise shaping (or <b>sns</b>
|
||||
for short) refers to a general collection of built-in
|
||||
algorithms used to decide which area of the picture should
|
||||
use relatively less bits, and where else to better transfer
|
||||
these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is
|
||||
50.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-segments</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the number of partitions
|
||||
to use during the segmentation of the sns algorithm.
|
||||
Segments should be in range 1 to 4. Default value is 4. This
|
||||
option has no effect for methods 3 and up, unless
|
||||
<b>-low_memory</b> is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-partition_limit</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Degrade quality by limiting the
|
||||
number of bits used by some macroblocks. Range is 0 (no
|
||||
degradation, the default) to 100 (full degradation). Useful
|
||||
values are usually around 30-70 for moderately large images.
|
||||
In the VP8 format, the so-called control partition has a
|
||||
limit of 512k and is used to store the following
|
||||
information: whether the macroblock is skipped, which
|
||||
segment it belongs to, whether it is coded as intra 4x4 or
|
||||
intra 16x16 mode, and finally the prediction modes to use
|
||||
for each of the sub-blocks. For a very large image, 512k
|
||||
only leaves room to few bits per 16x16 macroblock. The
|
||||
absolute minimum is 4 bits per macroblock. Skip, segment,
|
||||
and mode information can use up almost all these 4 bits
|
||||
(although the case is unlikely), which is problematic for
|
||||
very large images. The partition_limit factor controls how
|
||||
frequently the most bit-costly mode (intra 4x4) will be
|
||||
used. This is useful in case the 512k limit is reached and
|
||||
the following message is displayed: <i>Error code: 6
|
||||
(PARTITION0_OVERFLOW: Partition #0 is too big to fit
|
||||
512k)</i>. If using <b>-partition_limit</b> is not enough to
|
||||
meet the 512k constraint, one should use less segments in
|
||||
order to save more header bits per macroblock. See the
|
||||
<b>-segments</b> option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOGGING
|
||||
OPTIONS</b> <br>
|
||||
These options control the level of output:</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
<p><b>-v</b></p></td>
|
||||
<td width="8%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Print extra information (encoding time in
|
||||
particular).</p> </td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-print_psnr</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average PSNR
|
||||
(Peak-Signal-To-Noise ratio).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-print_ssim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average SSIM
|
||||
(structural similarity metric, see
|
||||
https://en.wikipedia.org/wiki/SSIM for additional
|
||||
details).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-print_lsim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report local
|
||||
similarity metric (sum of lowest error amongst the
|
||||
collocated pixel neighbors).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-progress</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Report encoding progress in
|
||||
percent.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-quiet</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Do not print anything.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-short</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Only print brief information (output file size and PSNR)
|
||||
for testing purposes.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-map</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Output additional ASCII-map of
|
||||
encoding information. Possible map values range from 1 to 6.
|
||||
This is only meant to help debugging.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>ADDITIONAL
|
||||
OPTIONS</b> <br>
|
||||
More advanced options are: <b><br>
|
||||
-s</b> <i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify that the input file
|
||||
actually consists of raw Y’CbCr samples following the
|
||||
ITU-R BT.601 recommendation, in 4:2:0 linear format. The
|
||||
luma plane has size <b>width</b> x <b>height</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-pre</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify some preprocessing
|
||||
steps. Using a value of ’2’ will trigger
|
||||
quality-dependent pseudo-random dithering during
|
||||
RGBA->YUVA conversion (lossy compression only).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-alpha_filter</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the predictive
|
||||
filtering method for the alpha plane. One of
|
||||
’none’, ’fast’ or
|
||||
’best’, in increasing complexity and slowness
|
||||
order. Default is ’fast’. Internally, alpha
|
||||
filtering is performed using four possible predictions
|
||||
(none, horizontal, vertical, gradient). The
|
||||
’best’ mode will try each mode in turn and pick
|
||||
the one which gives the smaller size. The ’fast’
|
||||
mode will just try to form an a priori guess without testing
|
||||
all modes.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-alpha_method</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the algorithm used for
|
||||
alpha compression: 0 or 1. Algorithm 0 denotes no
|
||||
compression, 1 uses WebP lossless format for compression.
|
||||
The default is 1.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-exact</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Preserve RGB values in transparent area. The default is
|
||||
off, to help compressibility.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-blend_alpha</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">This option blends the alpha
|
||||
channel (if present) with the source using the background
|
||||
color specified in hexadecimal as 0xrrggbb. The alpha
|
||||
channel is afterward reset to the opaque value 255.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-noalpha</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Using this option will discard
|
||||
the alpha channel.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-hint</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the hint about input
|
||||
image type. Possible values are: <b>photo</b>,
|
||||
<b>picture</b> or <b>graph</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>exif</b>,
|
||||
<b>icc</b>, <b>xmp</b>. The default is <b>none</b>.</p>
|
||||
|
||||
<p style="margin-left:22%; margin-top: 1em">Note: each
|
||||
input format may not support all combinations.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-noasm</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="53%">
|
||||
|
||||
|
||||
<p>Disable all assembly optimizations.</p></td>
|
||||
<td width="25%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp -q 50
|
||||
-lossless picture.png -o picture_lossless.webp <br>
|
||||
cwebp -q 70 picture_with_alpha.png -o
|
||||
picture_with_alpha.webp <br>
|
||||
cwebp -sns 70 -f 50 -size 60000 picture.png -o picture.webp
|
||||
<br>
|
||||
cwebp -o picture.webp -- ---picture.png</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>(1),
|
||||
<b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,340 @@
|
||||
CWEBP(1) General Commands Manual CWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
cwebp - compress an image file to a WebP file
|
||||
|
||||
SYNOPSIS
|
||||
cwebp [options] input_file -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the cwebp command.
|
||||
|
||||
cwebp compresses an image using the WebP format. Input format can be
|
||||
either PNG, JPEG, TIFF, WebP or raw Y'CbCr samples. Note: Animated PNG
|
||||
and WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, cwebp will
|
||||
perform compression but only report statistics. Using "-" as
|
||||
output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with a '-' for instance. This option must ap-
|
||||
pear last. Any other options afterward will be ignored.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-H, -longhelp
|
||||
A summary of all the possible options.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossless
|
||||
Encode the image without any loss. For images with fully trans-
|
||||
parent area, the invisible pixel values (R/G/B or Y/U/V) will be
|
||||
preserved only if the -exact option is used.
|
||||
|
||||
-near_lossless int
|
||||
Specify the level of near-lossless image preprocessing. This op-
|
||||
tion adjusts pixel values to help compressibility, but has mini-
|
||||
mal impact on the visual quality. It triggers lossless compres-
|
||||
sion mode automatically. The range is 0 (maximum preprocessing)
|
||||
to 100 (no preprocessing, the default). The typical value is
|
||||
around 60. Note that lossy with -q 100 can at times yield better
|
||||
results.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossy compression (default), a small factor produces
|
||||
a smaller file with lower quality. Best quality is achieved by
|
||||
using a value of 100.
|
||||
In case of lossless compression (specified by the -lossless op-
|
||||
tion), a small factor enables faster compression speed, but pro-
|
||||
duces a larger file. Maximum compression is achieved by using a
|
||||
value of 100.
|
||||
|
||||
-z int Switch on lossless compression mode with the specified level be-
|
||||
tween 0 and 9, with level 0 being the fastest, 9 being the slow-
|
||||
est. Fast mode produces larger file size than slower ones. A
|
||||
good default is -z 6. This option is actually a shortcut for
|
||||
some predefined settings for quality and method. If options -q
|
||||
or -m are subsequently used, they will invalidate the effect of
|
||||
this option.
|
||||
|
||||
-alpha_q int
|
||||
Specify the compression factor for alpha compression between 0
|
||||
and 100. Lossless compression of alpha is achieved using a
|
||||
value of 100, while the lower values result in a lossy compres-
|
||||
sion. The default is 100.
|
||||
|
||||
-preset string
|
||||
Specify a set of pre-defined parameters to suit a particular
|
||||
type of source material. Possible values are: default, photo,
|
||||
picture, drawing, icon, text. Since -preset overwrites the other
|
||||
parameters' values (except the -q one), this option should
|
||||
preferably appear first in the order of the arguments.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and de-
|
||||
cide on the quality gain. Lower value can result in faster pro-
|
||||
cessing time at the expense of larger file size and lower com-
|
||||
pression quality.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the source to a rectangle with top-left corner at coordi-
|
||||
nates (x_position, y_position) and size width x height. This
|
||||
cropping area must be fully contained within the source rectan-
|
||||
gle. Note: the cropping is applied before any scaling.
|
||||
|
||||
-resize width height
|
||||
Resize the source to a rectangle with size width x height. If
|
||||
either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio. Note:
|
||||
scaling is applied after cropping.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-low_memory
|
||||
Reduce memory usage of lossy encoding by saving four times the
|
||||
compressed size (typically). This will make the encoding slower
|
||||
and the output slightly different in size and distortion. This
|
||||
flag is only effective for methods 3 and up, and is off by de-
|
||||
fault. Note that leaving this flag off will have some side ef-
|
||||
fects on the bitstream: it forces certain bitstream features
|
||||
like number of partitions (forced to 1). Note that a more de-
|
||||
tailed report of bitstream size is printed by cwebp when using
|
||||
this option.
|
||||
|
||||
|
||||
LOSSY OPTIONS
|
||||
These options are only effective when doing lossy encoding (the de-
|
||||
fault, with or without alpha).
|
||||
|
||||
|
||||
-size int
|
||||
Specify a target size (in bytes) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-psnr float
|
||||
Specify a target PSNR (in dB) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-pass int
|
||||
Set a maximum number of passes to use during the dichotomy used
|
||||
by options -size or -psnr. Maximum value is 10, default is 1.
|
||||
If options -size or -psnr were used, but -pass wasn't specified,
|
||||
a default value of '6' passes will be used.
|
||||
|
||||
-qrange int int
|
||||
Specifies the permissible interval for the quality factor. This
|
||||
is particularly useful when using multi-pass (-size or -psnr op-
|
||||
tions). Default is 0 100. If the quality factor is outside
|
||||
this range, it will be clamped. If the minimum value must be
|
||||
less or equal to the maximum one.
|
||||
|
||||
-af Turns auto-filter on. This algorithm will spend additional time
|
||||
optimizing the filtering strength to reach a well-balanced qual-
|
||||
ity.
|
||||
|
||||
-jpeg_like
|
||||
Change the internal parameter mapping to better match the ex-
|
||||
pected size of JPEG compression. This flag will generally pro-
|
||||
duce an output file of similar size to its JPEG equivalent (for
|
||||
the same -q setting), but with less visual distortion.
|
||||
|
||||
|
||||
Advanced options:
|
||||
|
||||
|
||||
-f int Specify the strength of the deblocking filter, between 0 (no
|
||||
filtering) and 100 (maximum filtering). A value of 0 will turn
|
||||
off any filtering. Higher value will increase the strength of
|
||||
the filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear. Typical
|
||||
values are usually in the range of 20 to 50.
|
||||
|
||||
-sharpness int
|
||||
Specify the sharpness of the filtering (if used). Range is 0
|
||||
(sharpest) to 7 (least sharp). Default is 0.
|
||||
|
||||
-strong
|
||||
Use strong filtering (if filtering is being used thanks to the
|
||||
-f option). Strong filtering is on by default.
|
||||
|
||||
-nostrong
|
||||
Disable strong filtering (if filtering is being used thanks to
|
||||
the -f option) and use simple filtering instead.
|
||||
|
||||
-sharp_yuv
|
||||
Use more accurate and sharper RGB->YUV conversion if needed.
|
||||
Note that this process is slower than the default 'fast'
|
||||
RGB->YUV conversion.
|
||||
|
||||
-sns int
|
||||
Specify the amplitude of the spatial noise shaping. Spatial
|
||||
noise shaping (or sns for short) refers to a general collection
|
||||
of built-in algorithms used to decide which area of the picture
|
||||
should use relatively less bits, and where else to better trans-
|
||||
fer these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is 50.
|
||||
|
||||
-segments int
|
||||
Change the number of partitions to use during the segmentation
|
||||
of the sns algorithm. Segments should be in range 1 to 4. De-
|
||||
fault value is 4. This option has no effect for methods 3 and
|
||||
up, unless -low_memory is used.
|
||||
|
||||
-partition_limit int
|
||||
Degrade quality by limiting the number of bits used by some mac-
|
||||
roblocks. Range is 0 (no degradation, the default) to 100 (full
|
||||
degradation). Useful values are usually around 30-70 for moder-
|
||||
ately large images. In the VP8 format, the so-called control
|
||||
partition has a limit of 512k and is used to store the following
|
||||
information: whether the macroblock is skipped, which segment it
|
||||
belongs to, whether it is coded as intra 4x4 or intra 16x16
|
||||
mode, and finally the prediction modes to use for each of the
|
||||
sub-blocks. For a very large image, 512k only leaves room to
|
||||
few bits per 16x16 macroblock. The absolute minimum is 4 bits
|
||||
per macroblock. Skip, segment, and mode information can use up
|
||||
almost all these 4 bits (although the case is unlikely), which
|
||||
is problematic for very large images. The partition_limit factor
|
||||
controls how frequently the most bit-costly mode (intra 4x4)
|
||||
will be used. This is useful in case the 512k limit is reached
|
||||
and the following message is displayed: Error code: 6 (PARTI-
|
||||
TION0_OVERFLOW: Partition #0 is too big to fit 512k). If using
|
||||
-partition_limit is not enough to meet the 512k constraint, one
|
||||
should use less segments in order to save more header bits per
|
||||
macroblock. See the -segments option.
|
||||
|
||||
|
||||
LOGGING OPTIONS
|
||||
These options control the level of output:
|
||||
|
||||
-v Print extra information (encoding time in particular).
|
||||
|
||||
-print_psnr
|
||||
Compute and report average PSNR (Peak-Signal-To-Noise ratio).
|
||||
|
||||
-print_ssim
|
||||
Compute and report average SSIM (structural similarity metric,
|
||||
see https://en.wikipedia.org/wiki/SSIM for additional details).
|
||||
|
||||
-print_lsim
|
||||
Compute and report local similarity metric (sum of lowest error
|
||||
amongst the collocated pixel neighbors).
|
||||
|
||||
-progress
|
||||
Report encoding progress in percent.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-short Only print brief information (output file size and PSNR) for
|
||||
testing purposes.
|
||||
|
||||
-map int
|
||||
Output additional ASCII-map of encoding information. Possible
|
||||
map values range from 1 to 6. This is only meant to help debug-
|
||||
ging.
|
||||
|
||||
|
||||
ADDITIONAL OPTIONS
|
||||
More advanced options are:
|
||||
|
||||
-s width height
|
||||
Specify that the input file actually consists of raw Y'CbCr sam-
|
||||
ples following the ITU-R BT.601 recommendation, in 4:2:0 linear
|
||||
format. The luma plane has size width x height.
|
||||
|
||||
-pre int
|
||||
Specify some preprocessing steps. Using a value of '2' will
|
||||
trigger quality-dependent pseudo-random dithering during
|
||||
RGBA->YUVA conversion (lossy compression only).
|
||||
|
||||
-alpha_filter string
|
||||
Specify the predictive filtering method for the alpha plane. One
|
||||
of 'none', 'fast' or 'best', in increasing complexity and slow-
|
||||
ness order. Default is 'fast'. Internally, alpha filtering is
|
||||
performed using four possible predictions (none, horizontal,
|
||||
vertical, gradient). The 'best' mode will try each mode in turn
|
||||
and pick the one which gives the smaller size. The 'fast' mode
|
||||
will just try to form an a priori guess without testing all
|
||||
modes.
|
||||
|
||||
-alpha_method int
|
||||
Specify the algorithm used for alpha compression: 0 or 1. Algo-
|
||||
rithm 0 denotes no compression, 1 uses WebP lossless format for
|
||||
compression. The default is 1.
|
||||
|
||||
-exact Preserve RGB values in transparent area. The default is off, to
|
||||
help compressibility.
|
||||
|
||||
-blend_alpha int
|
||||
This option blends the alpha channel (if present) with the
|
||||
source using the background color specified in hexadecimal as
|
||||
0xrrggbb. The alpha channel is afterward reset to the opaque
|
||||
value 255.
|
||||
|
||||
-noalpha
|
||||
Using this option will discard the alpha channel.
|
||||
|
||||
-hint string
|
||||
Specify the hint about input image type. Possible values are:
|
||||
photo, picture or graph.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, exif, icc, xmp.
|
||||
The default is none.
|
||||
|
||||
Note: each input format may not support all combinations.
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
cwebp -q 50 -lossless picture.png -o picture_lossless.webp
|
||||
cwebp -q 70 picture_with_alpha.png -o picture_with_alpha.webp
|
||||
cwebp -sns 70 -f 50 -size 60000 picture.png -o picture.webp
|
||||
cwebp -o picture.webp -- ---picture.png
|
||||
|
||||
|
||||
AUTHORS
|
||||
cwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
dwebp(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
March 17, 2022 CWEBP(1)
|
||||
@@ -0,0 +1,369 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>DWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">DWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp -
|
||||
decompress a WebP file to an image file</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
[<i>options</i>] <i>input_file.webp</i></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>dwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
decompresses WebP files into PNG, PAM, PPM or PGM images.
|
||||
Note: Animated WebP files are not supported.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are:</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
<p><b>-h</b></p></td>
|
||||
<td width="8%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p>Print usage summary.</p></td>
|
||||
<td width="48%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
file (as PNG format by default). Using "-" as
|
||||
output name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>--</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’-’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from
|
||||
<i>stdin</i> instead of a file.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-bmp</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to uncompressed BMP.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-tiff</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to uncompressed TIFF.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-pam</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to PAM (retains alpha).</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-ppm</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to PPM (discards alpha).</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-pgm</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to PGM. The output consists of
|
||||
luma/chroma samples instead of RGB, using the IMC4 layout.
|
||||
This option is mainly for verification and debugging
|
||||
purposes.</p> </td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-yuv</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Change the output format to raw YUV. The output consists
|
||||
of luma/chroma-U/chroma-V samples instead of RGB, saved
|
||||
sequentially as individual planes. This option is mainly for
|
||||
verification and debugging purposes.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nofancy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the fancy
|
||||
upscaler for YUV420. This may lead to jaggy edges
|
||||
(especially the red ones), but should be faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nofilter</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the in-loop
|
||||
filtering process even if it is required by the bitstream.
|
||||
This may produce visible blocks on the non-compliant output,
|
||||
but it will make the decoding faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-dither</b>
|
||||
<i>strength</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a dithering
|
||||
<b>strength</b> between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding
|
||||
banding artifacts.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-alpha_dither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If the compressed file contains
|
||||
a transparency plane that was quantized during compression,
|
||||
this flag will allow dithering the reconstructed plane in
|
||||
order to generate smoother transparency gradients.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nodither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable all dithering
|
||||
(default).</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>-mt</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p>Use multi-threading for decoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-crop</b> <i>x_position
|
||||
y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the decoded picture to a
|
||||
rectangle with top-left corner at coordinates
|
||||
(<b>x_position</b>, <b>y_position</b>) and size <b>width</b>
|
||||
x <b>height</b>. This cropping area must be fully contained
|
||||
within the source rectangle. The top-left corner will be
|
||||
snapped to even coordinates if needed. This option is meant
|
||||
to reduce the memory needed for cropping large images. Note:
|
||||
the cropping is applied <i>before</i> any scaling.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-flip</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Flip decoded image vertically (can be useful for OpenGL
|
||||
textures for instance).</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-resize</b>, <b>-scale</b>
|
||||
<i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Rescale the decoded picture to
|
||||
dimension <b>width</b> x <b>height</b>. This option is
|
||||
mostly intended to reducing the memory needed to decode
|
||||
large images, when only a small version is needed
|
||||
(thumbnail, preview, etc.). Note: scaling is applied
|
||||
<i>after</i> cropping. If either (but not both) of the
|
||||
<b>width</b> or <b>height</b> parameters is 0, the value
|
||||
will be calculated preserving the aspect-ratio.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-quiet</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Do not print anything.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-v</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Print extra information (decoding time in
|
||||
particular).</p> </td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-noasm</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Disable all assembly optimizations.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp
|
||||
picture.webp -o output.png <br>
|
||||
dwebp picture.webp -ppm -o output.ppm <br>
|
||||
dwebp -o output.ppm -- ---picture.webp <br>
|
||||
cat picture.webp | dwebp -o - -- - > output.ppm</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>gif2webp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>Output file
|
||||
format details</b> <br>
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html <br>
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html <br>
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html <br>
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,142 @@
|
||||
DWEBP(1) General Commands Manual DWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
dwebp - decompress a WebP file to an image file
|
||||
|
||||
SYNOPSIS
|
||||
dwebp [options] input_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the dwebp command.
|
||||
|
||||
dwebp decompresses WebP files into PNG, PAM, PPM or PGM images. Note:
|
||||
Animated WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-h Print usage summary.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-o string
|
||||
Specify the name of the output file (as PNG format by default).
|
||||
Using "-" as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must ap-
|
||||
pear last. Any other options afterward will be ignored. If the
|
||||
input file is "-", the data will be read from stdin instead of a
|
||||
file.
|
||||
|
||||
-bmp Change the output format to uncompressed BMP.
|
||||
|
||||
-tiff Change the output format to uncompressed TIFF.
|
||||
|
||||
-pam Change the output format to PAM (retains alpha).
|
||||
|
||||
-ppm Change the output format to PPM (discards alpha).
|
||||
|
||||
-pgm Change the output format to PGM. The output consists of
|
||||
luma/chroma samples instead of RGB, using the IMC4 layout. This
|
||||
option is mainly for verification and debugging purposes.
|
||||
|
||||
-yuv Change the output format to raw YUV. The output consists of
|
||||
luma/chroma-U/chroma-V samples instead of RGB, saved sequen-
|
||||
tially as individual planes. This option is mainly for verifica-
|
||||
tion and debugging purposes.
|
||||
|
||||
-nofancy
|
||||
Don't use the fancy upscaler for YUV420. This may lead to jaggy
|
||||
edges (especially the red ones), but should be faster.
|
||||
|
||||
-nofilter
|
||||
Don't use the in-loop filtering process even if it is required
|
||||
by the bitstream. This may produce visible blocks on the non-
|
||||
compliant output, but it will make the decoding faster.
|
||||
|
||||
-dither strength
|
||||
Specify a dithering strength between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding band-
|
||||
ing artifacts.
|
||||
|
||||
-alpha_dither
|
||||
If the compressed file contains a transparency plane that was
|
||||
quantized during compression, this flag will allow dithering the
|
||||
reconstructed plane in order to generate smoother transparency
|
||||
gradients.
|
||||
|
||||
-nodither
|
||||
Disable all dithering (default).
|
||||
|
||||
-mt Use multi-threading for decoding, if possible.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the decoded picture to a rectangle with top-left corner at
|
||||
coordinates (x_position, y_position) and size width x height.
|
||||
This cropping area must be fully contained within the source
|
||||
rectangle. The top-left corner will be snapped to even coordi-
|
||||
nates if needed. This option is meant to reduce the memory
|
||||
needed for cropping large images. Note: the cropping is applied
|
||||
before any scaling.
|
||||
|
||||
-flip Flip decoded image vertically (can be useful for OpenGL textures
|
||||
for instance).
|
||||
|
||||
-resize, -scale width height
|
||||
Rescale the decoded picture to dimension width x height. This
|
||||
option is mostly intended to reducing the memory needed to de-
|
||||
code large images, when only a small version is needed (thumb-
|
||||
nail, preview, etc.). Note: scaling is applied after cropping.
|
||||
If either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-v Print extra information (decoding time in particular).
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
dwebp picture.webp -o output.png
|
||||
dwebp picture.webp -ppm -o output.ppm
|
||||
dwebp -o output.ppm -- ---picture.webp
|
||||
cat picture.webp | dwebp -o - -- - > output.ppm
|
||||
|
||||
|
||||
AUTHORS
|
||||
dwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), gif2webp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
Output file format details
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info
|
||||
|
||||
|
||||
|
||||
November 17, 2021 DWEBP(1)
|
||||
@@ -0,0 +1,327 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>GIF2WEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">GIF2WEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp -
|
||||
Convert a GIF image to WebP</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
[<i>options</i>] <i>input_file.gif -o
|
||||
output_file.webp</i></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>gif2webp</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
converts a GIF image to a WebP image.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
-o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>gif2webp</b> will perform
|
||||
conversion but only report statistics. Using "-"
|
||||
as output name will direct output to
|
||||
’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>--</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’-’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from
|
||||
<i>stdin</i> instead of a file.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-h, -help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Usage information.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-lossy</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Encode the image using lossy compression.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-mixed</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Mixed compression mode: optimize compression of the
|
||||
image by picking either lossy or lossless compression for
|
||||
each frame heuristically.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-q</b> <i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossless compression (default), a small factor
|
||||
enables faster compression speed, but produces a larger
|
||||
file. Maximum compression is achieved by using a value of
|
||||
100. <br>
|
||||
In case of lossy compression (specified by the -lossy
|
||||
option), a small factor produces a smaller file with lower
|
||||
quality. Best quality is achieved by using a value of
|
||||
100.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-m</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Specify the compression method to use. This parameter
|
||||
controls the trade off between encoding speed and the
|
||||
compressed file size and quality. Possible values range from
|
||||
0 to 6. Default value is 4. When higher values are used, the
|
||||
encoder will spend more time inspecting additional encoding
|
||||
possibilities and decide on the quality gain. Lower value
|
||||
can result is faster processing time at the expense of
|
||||
larger file size and lower compression quality.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-min_size</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode image to achieve
|
||||
smallest size. This disables key frame insertion and picks
|
||||
the dispose method resulting in the smallest output for each
|
||||
frame. It uses lossless compression by default, but can be
|
||||
combined with -q, -m, -lossy or -mixed options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-kmin</b> <i>int</i> <b><br>
|
||||
-kmax</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the minimum and maximum
|
||||
distance between consecutive key frames (independently
|
||||
decodable frames) in the output animation. The tool will
|
||||
insert some key frames into the output animation as needed
|
||||
so that this criteria is satisfied. <br>
|
||||
A ’kmax’ value of 0 will turn off insertion of
|
||||
key frames. A ’kmax’ value of 1 will result in
|
||||
all frames being key frames. ’kmin’ value is not
|
||||
taken into account in both these special cases. Typical
|
||||
values are in the range 3 to 30. Default values are kmin =
|
||||
9, kmax = 17 for lossless compression and kmin = 3, kmax = 5
|
||||
for lossy compression. <br>
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50). <br>
|
||||
When lower values are used, more frames will be converted to
|
||||
key frames. This may lead to smaller number of frames
|
||||
required to decode a frame on average, thereby improving the
|
||||
decoding performance. But this may lead to slightly bigger
|
||||
file sizes. Higher values may lead to worse decoding
|
||||
performance, but smaller file sizes. <br>
|
||||
Some restrictions: <br>
|
||||
(i) kmin < kmax, <br>
|
||||
(ii) kmin >= kmax / 2 + 1 and <br>
|
||||
(iii) kmax - kmin <= 30. <br>
|
||||
If any of these restrictions are not met, they will be
|
||||
enforced automatically.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>icc</b>,
|
||||
<b>xmp</b>. The default is <b>xmp</b>.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-f</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>For lossy encoding only (specified by the -lossy
|
||||
option). Specify the strength of the deblocking filter,
|
||||
between 0 (no filtering) and 100 (maximum filtering). A
|
||||
value of 0 will turn off any filtering. Higher value will
|
||||
increase the strength of the filtering process applied after
|
||||
decoding the picture. The higher the value the smoother the
|
||||
picture will appear. Typical values are usually in the range
|
||||
of 20 to 50.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-mt</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Use multi-threading for encoding, if possible.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-loop_compatibility</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If enabled, handle the loop
|
||||
information in a compatible fashion for Chrome version prior
|
||||
to M62 (inclusive) and Firefox.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-v</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p>Print extra information.</p></td>
|
||||
<td width="42%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-quiet</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p>Do not print anything.</p></td>
|
||||
<td width="42%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp
|
||||
picture.gif -o picture.webp <br>
|
||||
gif2webp -q 70 picture.gif -o picture.webp <br>
|
||||
gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp <br>
|
||||
gif2webp -lossy -f 50 picture.gif -o picture.webp <br>
|
||||
gif2webp -q 70 -o picture.webp -- ---picture.gif <br>
|
||||
cat picture.gif | gif2webp -o - -- - > output.webp</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Urvang Joshi <urvang@google.com>,
|
||||
for the Debian project (and may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>dwebp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,152 @@
|
||||
GIF2WEBP(1) General Commands Manual GIF2WEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
gif2webp - Convert a GIF image to WebP
|
||||
|
||||
SYNOPSIS
|
||||
gif2webp [options] input_file.gif -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the gif2webp command.
|
||||
|
||||
gif2webp converts a GIF image to a WebP image.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, gif2webp
|
||||
will perform conversion but only report statistics. Using "-"
|
||||
as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must ap-
|
||||
pear last. Any other options afterward will be ignored. If the
|
||||
input file is "-", the data will be read from stdin instead of a
|
||||
file.
|
||||
|
||||
-h, -help
|
||||
Usage information.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossy Encode the image using lossy compression.
|
||||
|
||||
-mixed Mixed compression mode: optimize compression of the image by
|
||||
picking either lossy or lossless compression for each frame
|
||||
heuristically.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossless compression (default), a small factor en-
|
||||
ables faster compression speed, but produces a larger file. Max-
|
||||
imum compression is achieved by using a value of 100.
|
||||
In case of lossy compression (specified by the -lossy option), a
|
||||
small factor produces a smaller file with lower quality. Best
|
||||
quality is achieved by using a value of 100.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and de-
|
||||
cide on the quality gain. Lower value can result is faster pro-
|
||||
cessing time at the expense of larger file size and lower com-
|
||||
pression quality.
|
||||
|
||||
-min_size
|
||||
Encode image to achieve smallest size. This disables key frame
|
||||
insertion and picks the dispose method resulting in the smallest
|
||||
output for each frame. It uses lossless compression by default,
|
||||
but can be combined with -q, -m, -lossy or -mixed options.
|
||||
|
||||
-kmin int
|
||||
|
||||
-kmax int
|
||||
Specify the minimum and maximum distance between consecutive key
|
||||
frames (independently decodable frames) in the output animation.
|
||||
The tool will insert some key frames into the output animation
|
||||
as needed so that this criteria is satisfied.
|
||||
A 'kmax' value of 0 will turn off insertion of key frames. A
|
||||
'kmax' value of 1 will result in all frames being key frames.
|
||||
'kmin' value is not taken into account in both these special
|
||||
cases. Typical values are in the range 3 to 30. Default values
|
||||
are kmin = 9, kmax = 17 for lossless compression and kmin = 3,
|
||||
kmax = 5 for lossy compression.
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50).
|
||||
When lower values are used, more frames will be converted to key
|
||||
frames. This may lead to smaller number of frames required to
|
||||
decode a frame on average, thereby improving the decoding per-
|
||||
formance. But this may lead to slightly bigger file sizes.
|
||||
Higher values may lead to worse decoding performance, but
|
||||
smaller file sizes.
|
||||
Some restrictions:
|
||||
(i) kmin < kmax,
|
||||
(ii) kmin >= kmax / 2 + 1 and
|
||||
(iii) kmax - kmin <= 30.
|
||||
If any of these restrictions are not met, they will be enforced
|
||||
automatically.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, icc, xmp. The de-
|
||||
fault is xmp.
|
||||
|
||||
-f int For lossy encoding only (specified by the -lossy option). Spec-
|
||||
ify the strength of the deblocking filter, between 0 (no filter-
|
||||
ing) and 100 (maximum filtering). A value of 0 will turn off
|
||||
any filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The higher
|
||||
the value the smoother the picture will appear. Typical values
|
||||
are usually in the range of 20 to 50.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-loop_compatibility
|
||||
If enabled, handle the loop information in a compatible fashion
|
||||
for Chrome version prior to M62 (inclusive) and Firefox.
|
||||
|
||||
-v Print extra information.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
gif2webp picture.gif -o picture.webp
|
||||
gif2webp -q 70 picture.gif -o picture.webp
|
||||
gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp
|
||||
gif2webp -lossy -f 50 picture.gif -o picture.webp
|
||||
gif2webp -q 70 -o picture.webp -- ---picture.gif
|
||||
cat picture.gif | gif2webp -o - -- - > output.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
gif2webp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Urvang Joshi <urvang@google.com>, for
|
||||
the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), dwebp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 GIF2WEBP(1)
|
||||
@@ -0,0 +1,242 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>IMG2WEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">IMG2WEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#FILE-LEVEL OPTIONS">FILE-LEVEL OPTIONS</a><br>
|
||||
<a href="#PER-FRAME OPTIONS">PER-FRAME OPTIONS</a><br>
|
||||
<a href="#EXAMPLE">EXAMPLE</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">img2webp -
|
||||
create animated WebP file from a sequence of input
|
||||
images.</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
[file_options] [[frame_options] frame_file]... <b><br>
|
||||
img2webp argument_file_name</b></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>img2webp</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
compresses a sequence of images using the animated WebP
|
||||
format. Input images can either be PNG, JPEG, TIFF or WebP.
|
||||
If a single file name (not starting with the character
|
||||
’-’) is supplied as the argument, the command
|
||||
line arguments are actually tokenized from this file. This
|
||||
allows for easy scripting or using a large number of
|
||||
arguments.</p>
|
||||
|
||||
<h2>FILE-LEVEL OPTIONS
|
||||
<a name="FILE-LEVEL OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The file-level
|
||||
options are applied at the beginning of the compression
|
||||
process, before the input frames are read. <b><br>
|
||||
-o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-min_size</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode images to achieve
|
||||
smallest size. This disables key frame insertion and picks
|
||||
the parameters resulting in the smallest output for each
|
||||
frame. It uses lossless compression by default, but can be
|
||||
combined with -q, -m, -lossy or -mixed options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-kmin</b> <i>int</i> <b><br>
|
||||
-kmax</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the minimum and maximum
|
||||
distance between consecutive key frames (independently
|
||||
decodable frames) in the output animation. The tool will
|
||||
insert some key frames into the output animation as needed
|
||||
so that this criteria is satisfied. <b><br>
|
||||
-mixed</b> Mixed compression mode: optimize compression of
|
||||
the image by picking either lossy or lossless compression
|
||||
for each frame heuristically. This global option disables
|
||||
the local option <b>-lossy</b> and <b>-lossless</b> .</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-loop</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specifies the number of times
|
||||
the animation should loop. Using ’0’ means
|
||||
’loop indefinitely’.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
<p><b>-v</b></p></td>
|
||||
<td width="8%"></td>
|
||||
<td width="24%">
|
||||
|
||||
|
||||
<p>Be more verbose.</p></td>
|
||||
<td width="54%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-h, -help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version numbers of
|
||||
the relevant libraries used.</p>
|
||||
|
||||
<h2>PER-FRAME OPTIONS
|
||||
<a name="PER-FRAME OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The per-frame
|
||||
options are applied for the images following as arguments in
|
||||
the command line. They can be modified any number of times
|
||||
preceding each particular input image.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-d</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="66%">
|
||||
|
||||
|
||||
<p>Specify the image duration in milliseconds.</p></td>
|
||||
<td width="12%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-lossless, -lossy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compress the next image(s)
|
||||
using lossless or lossy compression mode. The default mode
|
||||
is lossless.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-q</b> <i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
between 0 and 100. The default is 75.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-m</b> <i>int</i></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Specify the compression method to use. This parameter
|
||||
controls the trade off between encoding speed and the
|
||||
compressed file size and quality. Possible values range from
|
||||
0 to 6. Default value is 4.</p></td></tr>
|
||||
</table>
|
||||
|
||||
<h2>EXAMPLE
|
||||
<a name="EXAMPLE"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">img2webp -loop
|
||||
2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp</p>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>(1),
|
||||
<b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,108 @@
|
||||
IMG2WEBP(1) General Commands Manual IMG2WEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
img2webp - create animated WebP file from a sequence of input images.
|
||||
|
||||
SYNOPSIS
|
||||
img2webp [file_options] [[frame_options] frame_file]...
|
||||
img2webp argument_file_name
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the img2webp command.
|
||||
|
||||
img2webp compresses a sequence of images using the animated WebP for-
|
||||
mat. Input images can either be PNG, JPEG, TIFF or WebP. If a single
|
||||
file name (not starting with the character '-') is supplied as the ar-
|
||||
gument, the command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number of argu-
|
||||
ments.
|
||||
|
||||
FILE-LEVEL OPTIONS
|
||||
The file-level options are applied at the beginning of the compression
|
||||
process, before the input frames are read.
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file.
|
||||
|
||||
-min_size
|
||||
Encode images to achieve smallest size. This disables key frame
|
||||
insertion and picks the parameters resulting in the smallest
|
||||
output for each frame. It uses lossless compression by default,
|
||||
but can be combined with -q, -m, -lossy or -mixed options.
|
||||
|
||||
-kmin int
|
||||
|
||||
-kmax int
|
||||
Specify the minimum and maximum distance between consecutive key
|
||||
frames (independently decodable frames) in the output animation.
|
||||
The tool will insert some key frames into the output animation
|
||||
as needed so that this criteria is satisfied.
|
||||
-mixed Mixed compression mode: optimize compression of the image
|
||||
by picking either lossy or lossless compression for each frame
|
||||
heuristically. This global option disables the local option
|
||||
-lossy and -lossless .
|
||||
|
||||
-loop int
|
||||
Specifies the number of times the animation should loop. Using
|
||||
'0' means 'loop indefinitely'.
|
||||
|
||||
-v Be more verbose.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-version
|
||||
Print the version numbers of the relevant libraries used.
|
||||
|
||||
|
||||
PER-FRAME OPTIONS
|
||||
The per-frame options are applied for the images following as arguments
|
||||
in the command line. They can be modified any number of times preceding
|
||||
each particular input image.
|
||||
|
||||
-d int Specify the image duration in milliseconds.
|
||||
|
||||
-lossless, -lossy
|
||||
Compress the next image(s) using lossless or lossy compression
|
||||
mode. The default mode is lossless.
|
||||
|
||||
-q float
|
||||
Specify the compression factor between 0 and 100. The default is
|
||||
75.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4.
|
||||
|
||||
|
||||
EXAMPLE
|
||||
img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
AUTHORS
|
||||
img2webp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
webpmux(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
January 5, 2022 IMG2WEBP(1)
|
||||
@@ -0,0 +1,512 @@
|
||||
# WebP tools
|
||||
|
||||
## Encoding tool
|
||||
|
||||
The examples/ directory contains tools for encoding (cwebp) and decoding (dwebp)
|
||||
images.
|
||||
|
||||
The easiest use should look like:
|
||||
|
||||
```shell
|
||||
cwebp input.png -q 80 -o output.webp
|
||||
```
|
||||
|
||||
which will convert the input file to a WebP file using a quality factor of 80 on
|
||||
a 0->100 scale (0 being the lowest quality, 100 being the best. Default value is
|
||||
75).
|
||||
|
||||
You might want to try the `-lossless` flag too, which will compress the source
|
||||
(in RGBA format) without any loss. The `-q` quality parameter will in this case
|
||||
control the amount of processing time spent trying to make the output file as
|
||||
small as possible.
|
||||
|
||||
A longer list of options is available using the `-longhelp` command line flag:
|
||||
|
||||
```shell
|
||||
> cwebp -longhelp
|
||||
Usage:
|
||||
cwebp [-preset <...>] [options] in_file [-o out_file]
|
||||
```
|
||||
|
||||
If input size (-s) for an image is not specified, it is assumed to be a PNG,
|
||||
JPEG, TIFF or WebP file. Note: Animated PNG and WebP files are not supported.
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-h / -help ............. short help
|
||||
-H / -longhelp ......... long help
|
||||
-q <float> ............. quality factor (0:small..100:big), default=75
|
||||
-alpha_q <int> ......... transparency-compression quality (0..100),
|
||||
default=100
|
||||
-preset <string> ....... preset setting, one of:
|
||||
default, photo, picture,
|
||||
drawing, icon, text
|
||||
-preset must come first, as it overwrites other parameters
|
||||
-z <int> ............... activates lossless preset with given
|
||||
level in [0:fast, ..., 9:slowest]
|
||||
|
||||
-m <int> ............... compression method (0=fast, 6=slowest), default=4
|
||||
-segments <int> ........ number of segments to use (1..4), default=4
|
||||
-size <int> ............ target size (in bytes)
|
||||
-psnr <float> .......... target PSNR (in dB. typically: 42)
|
||||
|
||||
-s <int> <int> ......... input size (width x height) for YUV
|
||||
-sns <int> ............. spatial noise shaping (0:off, 100:max), default=50
|
||||
-f <int> ............... filter strength (0=off..100), default=60
|
||||
-sharpness <int> ....... filter sharpness (0:most .. 7:least sharp), default=0
|
||||
-strong ................ use strong filter instead of simple (default)
|
||||
-nostrong .............. use simple filter instead of strong
|
||||
-sharp_yuv ............. use sharper (and slower) RGB->YUV conversion
|
||||
-partition_limit <int> . limit quality to fit the 512k limit on
|
||||
the first partition (0=no degradation ... 100=full)
|
||||
-pass <int> ............ analysis pass number (1..10)
|
||||
-qrange <min> <max> .... specifies the permissible quality range
|
||||
(default: 0 100)
|
||||
-crop <x> <y> <w> <h> .. crop picture with the given rectangle
|
||||
-resize <w> <h> ........ resize picture (*after* any cropping)
|
||||
-mt .................... use multi-threading if available
|
||||
-low_memory ............ reduce memory usage (slower encoding)
|
||||
-map <int> ............. print map of extra info
|
||||
-print_psnr ............ prints averaged PSNR distortion
|
||||
-print_ssim ............ prints averaged SSIM distortion
|
||||
-print_lsim ............ prints local-similarity distortion
|
||||
-d <file.pgm> .......... dump the compressed output (PGM file)
|
||||
-alpha_method <int> .... transparency-compression method (0..1), default=1
|
||||
-alpha_filter <string> . predictive filtering for alpha plane,
|
||||
one of: none, fast (default) or best
|
||||
-exact ................. preserve RGB values in transparent area, default=off
|
||||
-blend_alpha <hex> ..... blend colors against background color
|
||||
expressed as RGB values written in
|
||||
hexadecimal, e.g. 0xc0e0d0 for red=0xc0
|
||||
green=0xe0 and blue=0xd0
|
||||
-noalpha ............... discard any transparency information
|
||||
-lossless .............. encode image losslessly, default=off
|
||||
-near_lossless <int> ... use near-lossless image
|
||||
preprocessing (0..100=off), default=100
|
||||
-hint <string> ......... specify image characteristics hint,
|
||||
one of: photo, picture or graph
|
||||
|
||||
-metadata <string> ..... comma separated list of metadata to
|
||||
copy from the input to the output if present.
|
||||
Valid values: all, none (default), exif, icc, xmp
|
||||
|
||||
-short ................. condense printed message
|
||||
-quiet ................. don't print anything
|
||||
-version ............... print version number and exit
|
||||
-noasm ................. disable all assembly optimizations
|
||||
-v ..................... verbose, e.g. print encoding/decoding times
|
||||
-progress .............. report encoding progress
|
||||
```
|
||||
|
||||
Experimental Options:
|
||||
|
||||
```
|
||||
-jpeg_like ............. roughly match expected JPEG size
|
||||
-af .................... auto-adjust filter strength
|
||||
-pre <int> ............. pre-processing filter
|
||||
```
|
||||
|
||||
The main options you might want to try in order to further tune the visual
|
||||
quality are:
|
||||
|
||||
-preset -sns -f -m
|
||||
|
||||
Namely:
|
||||
|
||||
* `preset` will set up a default encoding configuration targeting a particular
|
||||
type of input. It should appear first in the list of options, so that
|
||||
subsequent options can take effect on top of this preset. Default value is
|
||||
'default'.
|
||||
* `sns` will progressively turn on (when going from 0 to 100) some additional
|
||||
visual optimizations (like: segmentation map re-enforcement). This option
|
||||
will balance the bit allocation differently. It tries to take bits from the
|
||||
"easy" parts of the picture and use them in the "difficult" ones instead.
|
||||
Usually, raising the sns value (at fixed -q value) leads to larger files,
|
||||
but with better quality. Typical value is around '75'.
|
||||
* `f` option directly links to the filtering strength used by the codec's
|
||||
in-loop processing. The higher the value, the smoother the highly-compressed
|
||||
area will look. This is particularly useful when aiming at very small files.
|
||||
Typical values are around 20-30. Note that using the option
|
||||
-strong/-nostrong will change the type of filtering. Use "-f 0" to turn
|
||||
filtering off.
|
||||
* `m` controls the trade-off between encoding speed and quality. Default is 4.
|
||||
You can try -m 5 or -m 6 to explore more (time-consuming) encoding
|
||||
possibilities. A lower value will result in faster encoding at the expense
|
||||
of quality.
|
||||
|
||||
## Decoding tool
|
||||
|
||||
There is a decoding sample in examples/dwebp.c which will take a .webp file and
|
||||
decode it to a PNG image file (amongst other formats). This is simply to
|
||||
demonstrate the use of the API. You can verify the file test.webp decodes to
|
||||
exactly the same as test_ref.ppm by using:
|
||||
|
||||
```shell
|
||||
cd examples
|
||||
./dwebp test.webp -ppm -o test.ppm
|
||||
diff test.ppm test_ref.ppm
|
||||
```
|
||||
|
||||
The full list of options is available using -h:
|
||||
|
||||
```shell
|
||||
> dwebp -h
|
||||
Usage: dwebp in_file [options] [-o out_file]
|
||||
```
|
||||
|
||||
Decodes the WebP image file to PNG format [Default]. Note: Animated WebP files
|
||||
are not supported.
|
||||
|
||||
Use following options to convert into alternate image formats:
|
||||
|
||||
```
|
||||
-pam ......... save the raw RGBA samples as a color PAM
|
||||
-ppm ......... save the raw RGB samples as a color PPM
|
||||
-bmp ......... save as uncompressed BMP format
|
||||
-tiff ........ save as uncompressed TIFF format
|
||||
-pgm ......... save the raw YUV samples as a grayscale PGM
|
||||
file with IMC4 layout
|
||||
-yuv ......... save the raw YUV samples in flat layout
|
||||
```
|
||||
|
||||
Other options are:
|
||||
|
||||
```
|
||||
-version ..... print version number and exit
|
||||
-nofancy ..... don't use the fancy YUV420 upscaler
|
||||
-nofilter .... disable in-loop filtering
|
||||
-nodither .... disable dithering
|
||||
-dither <d> .. dithering strength (in 0..100)
|
||||
-alpha_dither use alpha-plane dithering if needed
|
||||
-mt .......... use multi-threading
|
||||
-crop <x> <y> <w> <h> ... crop output with the given rectangle
|
||||
-resize <w> <h> ......... resize output (*after* any cropping)
|
||||
-flip ........ flip the output vertically
|
||||
-alpha ....... only save the alpha plane
|
||||
-incremental . use incremental decoding (useful for tests)
|
||||
-h ........... this help message
|
||||
-v ........... verbose (e.g. print encoding/decoding times)
|
||||
-quiet ....... quiet mode, don't print anything
|
||||
-noasm ....... disable all assembly optimizations
|
||||
```
|
||||
|
||||
## WebP file analysis tool
|
||||
|
||||
`webpinfo` can be used to print out the chunk level structure and bitstream
|
||||
header information of WebP files. It can also check if the files are of valid
|
||||
WebP format.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
webpinfo [options] in_files
|
||||
```
|
||||
|
||||
Note: there could be multiple input files; options must come before input files.
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-version ........... Print version number and exit.
|
||||
-quiet ............. Do not show chunk parsing information.
|
||||
-diag .............. Show parsing error diagnosis.
|
||||
-summary ........... Show chunk stats summary.
|
||||
-bitstream_info .... Parse bitstream header.
|
||||
```
|
||||
|
||||
## Visualization tool
|
||||
|
||||
There's a little self-serve visualization tool called 'vwebp' under the
|
||||
examples/ directory. It uses OpenGL to open a simple drawing window and show a
|
||||
decoded WebP file. It's not yet integrated in the automake build system, but you
|
||||
can try to manually compile it using the recommendations below.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
vwebp in_file [options]
|
||||
```
|
||||
|
||||
Decodes the WebP image file and visualize it using OpenGL
|
||||
|
||||
Options are:
|
||||
|
||||
```
|
||||
-version ..... print version number and exit
|
||||
-noicc ....... don't use the icc profile if present
|
||||
-nofancy ..... don't use the fancy YUV420 upscaler
|
||||
-nofilter .... disable in-loop filtering
|
||||
-dither <int> dithering strength (0..100), default=50
|
||||
-noalphadither disable alpha plane dithering
|
||||
-usebgcolor .. display background color
|
||||
-mt .......... use multi-threading
|
||||
-info ........ print info
|
||||
-h ........... this help message
|
||||
```
|
||||
|
||||
Keyboard shortcuts:
|
||||
|
||||
```
|
||||
'c' ................ toggle use of color profile
|
||||
'b' ................ toggle background color display
|
||||
'i' ................ overlay file information
|
||||
'd' ................ disable blending & disposal (debug)
|
||||
'q' / 'Q' / ESC .... quit
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
Prerequisites:
|
||||
|
||||
1. OpenGL & OpenGL Utility Toolkit (GLUT)
|
||||
|
||||
Linux: `sudo apt-get install freeglut3-dev mesa-common-dev`
|
||||
|
||||
Mac + Xcode: These libraries should be available in the OpenGL / GLUT
|
||||
frameworks.
|
||||
|
||||
Windows: http://freeglut.sourceforge.net/index.php#download
|
||||
|
||||
2. (Optional) qcms (Quick Color Management System)
|
||||
|
||||
1. Download qcms from Mozilla / Chromium:
|
||||
https://hg.mozilla.org/mozilla-central/file/0e7639e3bdfb/gfx/qcms
|
||||
https://source.chromium.org/chromium/chromium/src/+/main:third_party/qcms/;drc=d4a2f8e1ed461d8fc05ed88d1ae2dc94c9773825
|
||||
2. Build and archive the source files as libqcms.a / qcms.lib
|
||||
3. Update makefile.unix / Makefile.vc
|
||||
1. Define WEBP_HAVE_QCMS
|
||||
2. Update include / library paths to reference the qcms directory.
|
||||
|
||||
Build using makefile.unix / Makefile.vc:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/vwebp
|
||||
> nmake /f Makefile.vc CFG=release-static \
|
||||
../obj/x64/release-static/bin/vwebp.exe
|
||||
```
|
||||
|
||||
## Animation creation tool
|
||||
|
||||
The utility `img2webp` can turn a sequence of input images (PNG, JPEG, ...) into
|
||||
an animated WebP file. It offers fine control over duration, encoding modes,
|
||||
etc.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
img2webp [file_options] [[frame_options] frame_file]...
|
||||
```
|
||||
|
||||
File-level options (only used at the start of compression):
|
||||
|
||||
```
|
||||
-min_size ............ minimize size
|
||||
-loop <int> .......... loop count (default: 0, = infinite loop)
|
||||
-kmax <int> .......... maximum number of frame between key-frames
|
||||
(0=only keyframes)
|
||||
-kmin <int> .......... minimum number of frame between key-frames
|
||||
(0=disable key-frames altogether)
|
||||
-mixed ............... use mixed lossy/lossless automatic mode
|
||||
-v ................... verbose mode
|
||||
-h ................... this help
|
||||
-version ............. print version number and exit
|
||||
```
|
||||
|
||||
Per-frame options (only used for subsequent images input):
|
||||
|
||||
```
|
||||
-d <int> ............. frame duration in ms (default: 100)
|
||||
-lossless ........... use lossless mode (default)
|
||||
-lossy ... ........... use lossy mode
|
||||
-q <float> ........... quality
|
||||
-m <int> ............. method to use
|
||||
```
|
||||
|
||||
example: `img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp`
|
||||
|
||||
Note: if a single file name is passed as the argument, the arguments will be
|
||||
tokenized from this file. The file name must not start with the character '-'.
|
||||
|
||||
## Animated GIF conversion
|
||||
|
||||
Animated GIF files can be converted to WebP files with animation using the
|
||||
gif2webp utility available under examples/. The files can then be viewed using
|
||||
vwebp.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
gif2webp [options] gif_file -o webp_file
|
||||
```
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-h / -help ............. this help
|
||||
-lossy ................. encode image using lossy compression
|
||||
-mixed ................. for each frame in the image, pick lossy
|
||||
or lossless compression heuristically
|
||||
-q <float> ............. quality factor (0:small..100:big)
|
||||
-m <int> ............... compression method (0=fast, 6=slowest)
|
||||
-min_size .............. minimize output size (default:off)
|
||||
lossless compression by default; can be
|
||||
combined with -q, -m, -lossy or -mixed
|
||||
options
|
||||
-kmin <int> ............ min distance between key frames
|
||||
-kmax <int> ............ max distance between key frames
|
||||
-f <int> ............... filter strength (0=off..100)
|
||||
-metadata <string> ..... comma separated list of metadata to
|
||||
copy from the input to the output if present
|
||||
Valid values: all, none, icc, xmp (default)
|
||||
-loop_compatibility .... use compatibility mode for Chrome
|
||||
version prior to M62 (inclusive)
|
||||
-mt .................... use multi-threading if available
|
||||
|
||||
-version ............... print version number and exit
|
||||
-v ..................... verbose
|
||||
-quiet ................. don't print anything
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
With the libgif development files installed, gif2webp can be built using
|
||||
makefile.unix:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/gif2webp
|
||||
```
|
||||
|
||||
or using autoconf:
|
||||
|
||||
```shell
|
||||
$ ./configure --enable-everything
|
||||
$ make
|
||||
```
|
||||
|
||||
## Comparison of animated images
|
||||
|
||||
Test utility anim_diff under examples/ can be used to compare two animated
|
||||
images (each can be GIF or WebP).
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
anim_diff <image1> <image2> [options]
|
||||
```
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-dump_frames <folder> dump decoded frames in PAM format
|
||||
-min_psnr <float> ... minimum per-frame PSNR
|
||||
-raw_comparison ..... if this flag is not used, RGB is
|
||||
premultiplied before comparison
|
||||
-max_diff <int> ..... maximum allowed difference per channel
|
||||
between corresponding pixels in subsequent
|
||||
frames
|
||||
-h .................. this help
|
||||
-version ............ print version number and exit
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
With the libgif development files installed, anim_diff can be built using
|
||||
makefile.unix:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/anim_diff
|
||||
```
|
||||
|
||||
or using autoconf:
|
||||
|
||||
```shell
|
||||
$ ./configure --enable-everything
|
||||
$ make
|
||||
```
|
||||
|
||||
## WebP Mux tool
|
||||
|
||||
The examples/ directory contains a tool (webpmux) for manipulating WebP files.
|
||||
The webpmux tool can be used to create an extended format WebP file and also to
|
||||
extract or strip relevant data from such a file.
|
||||
|
||||
A list of options is available using the -help command line flag:
|
||||
|
||||
```shell
|
||||
> webpmux -help
|
||||
Usage: webpmux -get GET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -set SET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -duration DURATION_OPTIONS [-duration ...]
|
||||
INPUT -o OUTPUT
|
||||
webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -frame FRAME_OPTIONS [-frame...] [-loop LOOP_COUNT]
|
||||
[-bgcolor BACKGROUND_COLOR] -o OUTPUT
|
||||
webpmux -info INPUT
|
||||
webpmux [-h|-help]
|
||||
webpmux -version
|
||||
webpmux argument_file_name
|
||||
|
||||
GET_OPTIONS:
|
||||
Extract relevant data:
|
||||
icc get ICC profile
|
||||
exif get EXIF metadata
|
||||
xmp get XMP metadata
|
||||
frame n get nth frame
|
||||
|
||||
SET_OPTIONS:
|
||||
Set color profile/metadata/parameters:
|
||||
loop LOOP_COUNT set the loop count
|
||||
bgcolor BACKGROUND_COLOR set the animation background color
|
||||
icc file.icc set ICC profile
|
||||
exif file.exif set EXIF metadata
|
||||
xmp file.xmp set XMP metadata
|
||||
where: 'file.icc' contains the ICC profile to be set,
|
||||
'file.exif' contains the EXIF metadata to be set
|
||||
'file.xmp' contains the XMP metadata to be set
|
||||
|
||||
DURATION_OPTIONS:
|
||||
Set duration of selected frames:
|
||||
duration set duration for all frames
|
||||
duration,frame set duration of a particular frame
|
||||
duration,start,end set duration of frames in the
|
||||
interval [start,end])
|
||||
where: 'duration' is the duration in milliseconds
|
||||
'start' is the start frame index
|
||||
'end' is the inclusive end frame index
|
||||
The special 'end' value '0' means: last frame.
|
||||
|
||||
STRIP_OPTIONS:
|
||||
Strip color profile/metadata:
|
||||
icc strip ICC profile
|
||||
exif strip EXIF metadata
|
||||
xmp strip XMP metadata
|
||||
|
||||
FRAME_OPTIONS(i):
|
||||
Create animation:
|
||||
file_i +di[+xi+yi[+mi[bi]]]
|
||||
where: 'file_i' is the i'th animation frame (WebP format),
|
||||
'di' is the pause duration before next frame,
|
||||
'xi','yi' specify the image offset for this frame,
|
||||
'mi' is the dispose method for this frame (0 or 1),
|
||||
'bi' is the blending method for this frame (+b or -b)
|
||||
|
||||
LOOP_COUNT:
|
||||
Number of times to repeat the animation.
|
||||
Valid range is 0 to 65535 [Default: 0 (infinite)].
|
||||
|
||||
BACKGROUND_COLOR:
|
||||
Background color of the canvas.
|
||||
A,R,G,B
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255 specifying
|
||||
the Alpha, Red, Green and Blue component values respectively
|
||||
[Default: 255,255,255,255]
|
||||
|
||||
INPUT & OUTPUT are in WebP format.
|
||||
|
||||
Note: The nature of EXIF, XMP and ICC data is not checked and is assumed to be
|
||||
valid.
|
||||
|
||||
Note: if a single file name is passed as the argument, the arguments will be
|
||||
tokenized from this file. The file name must not start with the character '-'.
|
||||
```
|
||||
@@ -0,0 +1,282 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>VWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">VWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#KEYBOARD SHORTCUTS">KEYBOARD SHORTCUTS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">vwebp -
|
||||
decompress a WebP file and display it in a window</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b>
|
||||
[<i>options</i>] <i>input_file.webp</i></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>vwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b>
|
||||
decompresses a WebP file and displays it in a window using
|
||||
OpenGL.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em"><b>-h</b></p></td>
|
||||
<td width="8%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em">Print usage summary.</p></td>
|
||||
<td width="48%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print version number and
|
||||
exit.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-noicc</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="56%">
|
||||
|
||||
|
||||
<p>Don’t use the ICC profile if present.</p></td>
|
||||
<td width="22%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nofancy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the fancy
|
||||
YUV420 upscaler.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-nofilter</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable in-loop filtering.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-dither</b>
|
||||
<i>strength</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a dithering
|
||||
<b>strength</b> between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding
|
||||
banding artifacts. Default: 50.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-noalphadither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">By default, quantized
|
||||
transparency planes are dithered during decompression, to
|
||||
smooth the gradients. This flag will prevent this
|
||||
dithering.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-usebgcolor</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Fill transparent areas with the
|
||||
bitstream’s own background color instead of
|
||||
checkerboard only. Default is white for non-animated
|
||||
images.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-mt</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Use multi-threading for decoding, if possible.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
<p><b>-info</b></p></td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Display image information on top of the decoded
|
||||
image.</p> </td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>--</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’-’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from
|
||||
<i>stdin</i> instead of a file.</p>
|
||||
|
||||
<h2>KEYBOARD SHORTCUTS
|
||||
<a name="KEYBOARD SHORTCUTS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em"><b>’c’</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em">Toggle use of color profile.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>’b’</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Toggle display of background color.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>’i’</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Overlay file information.</p></td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
<p><b>’d’</b></p></td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p>Disable blending and disposal process, for debugging
|
||||
purposes.</p> </td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>’q’ /
|
||||
’Q’ / ESC</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Quit.</p>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">vwebp
|
||||
picture.webp <br>
|
||||
vwebp picture.webp -mt -dither 0 <br>
|
||||
vwebp -- ---picture.webp</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written for the Debian project (and may be used by
|
||||
others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>(1)
|
||||
<br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,103 @@
|
||||
VWEBP(1) General Commands Manual VWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
vwebp - decompress a WebP file and display it in a window
|
||||
|
||||
SYNOPSIS
|
||||
vwebp [options] input_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the vwebp command.
|
||||
|
||||
vwebp decompresses a WebP file and displays it in a window using
|
||||
OpenGL.
|
||||
|
||||
OPTIONS
|
||||
-h Print usage summary.
|
||||
|
||||
-version
|
||||
Print version number and exit.
|
||||
|
||||
-noicc Don't use the ICC profile if present.
|
||||
|
||||
-nofancy
|
||||
Don't use the fancy YUV420 upscaler.
|
||||
|
||||
-nofilter
|
||||
Disable in-loop filtering.
|
||||
|
||||
-dither strength
|
||||
Specify a dithering strength between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding band-
|
||||
ing artifacts. Default: 50.
|
||||
|
||||
-noalphadither
|
||||
By default, quantized transparency planes are dithered during
|
||||
decompression, to smooth the gradients. This flag will prevent
|
||||
this dithering.
|
||||
|
||||
-usebgcolor
|
||||
Fill transparent areas with the bitstream's own background color
|
||||
instead of checkerboard only. Default is white for non-animated
|
||||
images.
|
||||
|
||||
-mt Use multi-threading for decoding, if possible.
|
||||
|
||||
-info Display image information on top of the decoded image.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must ap-
|
||||
pear last. Any other options afterward will be ignored. If the
|
||||
input file is "-", the data will be read from stdin instead of a
|
||||
file.
|
||||
|
||||
|
||||
|
||||
KEYBOARD SHORTCUTS
|
||||
|
||||
'c' Toggle use of color profile.
|
||||
|
||||
'b' Toggle display of background color.
|
||||
|
||||
'i' Overlay file information.
|
||||
|
||||
'd' Disable blending and disposal process, for debugging purposes.
|
||||
|
||||
'q' / 'Q' / ESC
|
||||
Quit.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
vwebp picture.webp
|
||||
vwebp picture.webp -mt -dither 0
|
||||
vwebp -- ---picture.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
vwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written for the Debian project (and may be used by
|
||||
others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
dwebp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 VWEBP(1)
|
||||
@@ -0,0 +1,186 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:58 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>WEBPINFO</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">WEBPINFO</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#INPUT">INPUT</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpinfo -
|
||||
print out the chunk level structure of WebP files along with
|
||||
basic integrity checks.</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
<i>OPTIONS INPUT</i> <b><br>
|
||||
webpinfo [-h|-help|-H|-longhelp]</b></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>webpinfo</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
can be used to print out the chunk level structure and
|
||||
bitstream header information of WebP files. It can also
|
||||
check if the files are of valid WebP format.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>-version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-quiet</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="58%">
|
||||
|
||||
|
||||
<p>Do not show chunk parsing information.</p></td>
|
||||
<td width="20%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p><b>-diag</b></p></td>
|
||||
<td width="2%"></td>
|
||||
<td width="58%">
|
||||
|
||||
|
||||
<p>Show parsing error diagnosis.</p></td>
|
||||
<td width="20%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>-summary</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Show chunk stats summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-bitstream_info</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Parse bitstream header.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-h, -help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-H, -longhelp</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Detailed usage
|
||||
instructions.</p>
|
||||
|
||||
<h2>INPUT
|
||||
<a name="INPUT"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Input files in
|
||||
WebP format. Input files must come last, following options
|
||||
(if any). There can be multiple input files.</p>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpinfo -h
|
||||
<br>
|
||||
webpinfo -diag -summary input_file.webp <br>
|
||||
webpinfo -bitstream_info input_file_1.webp input_file_2.webp
|
||||
<br>
|
||||
webpinfo *.webp</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Hui Su <huisu@google.com>, for the
|
||||
Debian project (and may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>(1)
|
||||
<br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,78 @@
|
||||
WEBPINFO(1) General Commands Manual WEBPINFO(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
webpinfo - print out the chunk level structure of WebP files along with
|
||||
basic integrity checks.
|
||||
|
||||
SYNOPSIS
|
||||
webpinfo OPTIONS INPUT
|
||||
webpinfo [-h|-help|-H|-longhelp]
|
||||
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the webpinfo command.
|
||||
|
||||
webpinfo can be used to print out the chunk level structure and bit-
|
||||
stream header information of WebP files. It can also check if the files
|
||||
are of valid WebP format.
|
||||
|
||||
|
||||
OPTIONS
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-quiet Do not show chunk parsing information.
|
||||
|
||||
-diag Show parsing error diagnosis.
|
||||
|
||||
-summary
|
||||
Show chunk stats summary.
|
||||
|
||||
-bitstream_info
|
||||
Parse bitstream header.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-H, -longhelp
|
||||
Detailed usage instructions.
|
||||
|
||||
|
||||
INPUT
|
||||
Input files in WebP format. Input files must come last, following op-
|
||||
tions (if any). There can be multiple input files.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
webpinfo -h
|
||||
webpinfo -diag -summary input_file.webp
|
||||
webpinfo -bitstream_info input_file_1.webp input_file_2.webp
|
||||
webpinfo *.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
webpinfo is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Hui Su <huisu@google.com>, for the De-
|
||||
bian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 WEBPINFO(1)
|
||||
@@ -0,0 +1,434 @@
|
||||
<!-- Creator : groff version 1.22.4 -->
|
||||
<!-- CreationDate: Fri Aug 5 23:54:57 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
pre { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
table { margin-top: 0; margin-bottom: 0; vertical-align: top }
|
||||
h1 { text-align: center }
|
||||
</style>
|
||||
<title>WEBPMUX</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align="center">WEBPMUX</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<h2>NAME
|
||||
<a name="NAME"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpmux -
|
||||
create animated WebP files from non-animated WebP images,
|
||||
extract frames from animated WebP images, and manage
|
||||
XMP/EXIF metadata and ICC profile.</p>
|
||||
|
||||
<h2>SYNOPSIS
|
||||
<a name="SYNOPSIS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux
|
||||
-get</b> <i>GET_OPTIONS INPUT</i> <b>-o</b> <i>OUTPUT</i>
|
||||
<b><br>
|
||||
webpmux -set</b> <i>SET_OPTIONS INPUT</i> <b>-o</b>
|
||||
<i>OUTPUT</i> <b><br>
|
||||
webpmux -strip</b> <i>STRIP_OPTIONS INPUT</i> <b>-o</b>
|
||||
<i>OUTPUT</i> <b><br>
|
||||
webpmux -frame</b> <i>FRAME_OPTIONS</i> <b>[ -frame ... ] [
|
||||
-loop</b> <i>LOOP_COUNT</i> <b>]</b></p>
|
||||
|
||||
<p style="margin-left:23%;"><b>[ -bgcolor</b>
|
||||
<i>BACKGROUND_COLOR</i> <b>] -o</b> <i>OUTPUT</i></p>
|
||||
|
||||
<p style="margin-left:11%;"><b>webpmux -duration</b>
|
||||
<i>DURATION OPTIONS</i> <b>[ -duration ... ]</b>
|
||||
<i>INPUT</i> <b>-o</b> <i>OUTPUT</i> <b><br>
|
||||
webpmux -info</b> <i>INPUT</i> <b><br>
|
||||
webpmux [-h|-help] <br>
|
||||
webpmux -version <br>
|
||||
webpmux argument_file_name</b></p>
|
||||
|
||||
<h2>DESCRIPTION
|
||||
<a name="DESCRIPTION"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>webpmux</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>
|
||||
can be used to create/extract from animated WebP files, as
|
||||
well as to add/extract/strip XMP/EXIF metadata and ICC
|
||||
profile. If a single file name (not starting with the
|
||||
character ’-’) is supplied as the argument, the
|
||||
command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number
|
||||
of arguments.</p>
|
||||
|
||||
<h2>OPTIONS
|
||||
<a name="OPTIONS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>GET_OPTIONS
|
||||
(-get):</b></p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>icc</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p>Get ICC profile.</p></td>
|
||||
<td width="51%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>exif</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p>Get EXIF metadata.</p></td>
|
||||
<td width="51%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>xmp</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p>Get XMP metadata.</p></td>
|
||||
<td width="51%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>frame</b> <i>n</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Get nth frame from an animated
|
||||
image. (n = 0 has a special meaning: last frame).</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>SET_OPTIONS
|
||||
(-set) <br>
|
||||
loop</b> <i>loop_count</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set loop count on an animated
|
||||
file.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’loop_count’ must be in range [0, 65535].
|
||||
<b><br>
|
||||
bgcolor</b> <i>A,R,G,B</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set the background color of the
|
||||
canvas on an animated file.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">where:
|
||||
’A’, ’R’, ’G’ and
|
||||
’B’ are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values
|
||||
respectively. <b><br>
|
||||
icc</b> <i>file.icc</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set ICC profile.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.icc’ contains the ICC profile to be set.
|
||||
<b><br>
|
||||
exif</b> <i>file.exif</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set EXIF metadata.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.exif’ contains the EXIF metadata to be
|
||||
set. <b><br>
|
||||
xmp</b> <i>file.xmp</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set XMP metadata.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.xmp’ contains the XMP metadata to be
|
||||
set.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>STRIP_OPTIONS
|
||||
(-strip)</b></p>
|
||||
|
||||
<table width="100%" border="0" rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>icc</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p>Strip ICC profile.</p></td>
|
||||
<td width="48%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>exif</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p>Strip EXIF metadata.</p></td>
|
||||
<td width="48%">
|
||||
</td></tr>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p><b>xmp</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p>Strip XMP metadata.</p></td>
|
||||
<td width="48%">
|
||||
</td></tr>
|
||||
</table>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>DURATION_OPTIONS
|
||||
(-duration)</b> <br>
|
||||
Amend the duration of a specific interval of frames. This
|
||||
option is only effective on animated WebP and has no effect
|
||||
on a single-frame file. <i><br>
|
||||
duration[,start[,end]]</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Where: <b><br>
|
||||
duration</b> is the duration for the interval in
|
||||
milliseconds (mandatory). Must be non-negative. <b><br>
|
||||
start</b> is the starting frame index of the interval
|
||||
(optional). <b><br>
|
||||
end</b> is the ending frame index (inclusive) of the
|
||||
interval (optional).</p>
|
||||
|
||||
<p style="margin-left:11%;">The three typical usages of
|
||||
this option are:</p>
|
||||
|
||||
<p style="margin-left:22%;"><b>-duration d</b> <br>
|
||||
set the duration to ’d’ for the whole animation.
|
||||
<b><br>
|
||||
-duration d,f</b> <br>
|
||||
set the duration of frame ’f’ to
|
||||
’d’. <b><br>
|
||||
-duration d,start,end</b> <br>
|
||||
set the duration to ’d’ for the whole
|
||||
[start,end] interval.</p>
|
||||
|
||||
<p style="margin-left:22%; margin-top: 1em">Note that the
|
||||
frames outside of the [start, end] interval will <br>
|
||||
remain untouched. <br>
|
||||
The ’end’ value ’0’ has the special
|
||||
meaning ’last frame of the animation’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><i>Reminder:</i></p>
|
||||
|
||||
<p style="margin-left:22%;">frame indexing starts at
|
||||
’1’.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>FRAME_OPTIONS
|
||||
(-frame)</b> <br>
|
||||
Create an animated WebP file from multiple (non-animated)
|
||||
WebP images. <i><br>
|
||||
file_i +di[+xi+yi[+mi[bi]]]</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Where: ’file_i’ is
|
||||
the i’th frame (WebP format),
|
||||
’xi’,’yi’ specify the image offset
|
||||
for this frame, ’di’ is the pause duration
|
||||
before next frame, ’mi’ is the dispose method
|
||||
for this frame (0 for NONE or 1 for BACKGROUND) and
|
||||
’bi’ is the blending method for this frame (+b
|
||||
for BLEND or -b for NO_BLEND). Argument ’bi’ can
|
||||
be omitted and will default to +b (BLEND). Also,
|
||||
’mi’ can be omitted if ’bi’ is
|
||||
omitted and will default to 0 (NONE). Finally, if
|
||||
’mi’ and ’bi’ are omitted then
|
||||
’xi’ and ’yi’ can be omitted and
|
||||
will default to +0+0.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-loop</b> <i>n</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Loop the frames n number of
|
||||
times. 0 indicates the frames should loop forever. Valid
|
||||
range is 0 to 65535 [Default: 0 (infinite)].</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>-bgcolor</b>
|
||||
<i>A,R,G,B</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Background color of the canvas.
|
||||
<br>
|
||||
where: ’A’, ’R’, ’G’ and
|
||||
’B’ are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values
|
||||
respectively [Default: 255,255,255,255].</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>INPUT</b>
|
||||
<br>
|
||||
Input file in WebP format.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>OUTPUT
|
||||
(-o)</b> <br>
|
||||
Output file in WebP format.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>Note:</b>
|
||||
<br>
|
||||
The nature of EXIF, XMP and ICC data is not checked and is
|
||||
assumed to <br>
|
||||
be valid.</p>
|
||||
|
||||
<h2>BUGS
|
||||
<a name="BUGS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting-patches/</p>
|
||||
|
||||
<h2>EXAMPLES
|
||||
<a name="EXAMPLES"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add ICC
|
||||
profile: <br>
|
||||
webpmux -set icc image_profile.icc in.webp -o
|
||||
icc_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract ICC
|
||||
profile: <br>
|
||||
webpmux -get icc icc_container.webp -o image_profile.icc</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip ICC
|
||||
profile: <br>
|
||||
webpmux -strip icc icc_container.webp -o
|
||||
without_icc.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add XMP
|
||||
metadata: <br>
|
||||
webpmux -set xmp image_metadata.xmp in.webp -o
|
||||
xmp_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract XMP
|
||||
metadata: <br>
|
||||
webpmux -get xmp xmp_container.webp -o
|
||||
image_metadata.xmp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip XMP
|
||||
metadata: <br>
|
||||
webpmux -strip xmp xmp_container.webp -o
|
||||
without_xmp.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add EXIF
|
||||
metadata: <br>
|
||||
webpmux -set exif image_metadata.exif in.webp -o
|
||||
exif_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract EXIF
|
||||
metadata: <br>
|
||||
webpmux -get exif exif_container.webp -o
|
||||
image_metadata.exif</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip EXIF
|
||||
metadata: <br>
|
||||
webpmux -strip exif exif_container.webp -o
|
||||
without_exif.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Create an
|
||||
animated WebP file from 3 (non-animated) WebP images: <br>
|
||||
webpmux -frame 1.webp +100 -frame 2.webp +100+50+50</p>
|
||||
|
||||
<p style="margin-left:23%;">-frame 3.webp +100+50+50+1+b
|
||||
-loop 10 -bgcolor 255,255,255,255 <br>
|
||||
-o anim_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Get the 2nd
|
||||
frame from an animated WebP file: <br>
|
||||
webpmux -get frame 2 anim_container.webp -o frame_2.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Using
|
||||
-get/-set/-strip with input file name starting with
|
||||
’-’: <br>
|
||||
webpmux -set icc image_profile.icc -o icc_container.webp --
|
||||
---in.webp <br>
|
||||
webpmux -get icc -o image_profile.icc --
|
||||
---icc_container.webp <br>
|
||||
webpmux -strip icc -o without_icc.webp --
|
||||
---icc_container.webp</p>
|
||||
|
||||
<h2>AUTHORS
|
||||
<a name="AUTHORS"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Vikas Arora
|
||||
<vikaas.arora@gmail.com>, for the Debian project (and
|
||||
may be used by others).</p>
|
||||
|
||||
<h2>SEE ALSO
|
||||
<a name="SEE ALSO"></a>
|
||||
</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>dwebp</b>(1), <b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,216 @@
|
||||
WEBPMUX(1) General Commands Manual WEBPMUX(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
webpmux - create animated WebP files from non-animated WebP images, ex-
|
||||
tract frames from animated WebP images, and manage XMP/EXIF metadata
|
||||
and ICC profile.
|
||||
|
||||
SYNOPSIS
|
||||
webpmux -get GET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -set SET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -frame FRAME_OPTIONS [ -frame ... ] [ -loop LOOP_COUNT ]
|
||||
[ -bgcolor BACKGROUND_COLOR ] -o OUTPUT
|
||||
webpmux -duration DURATION OPTIONS [ -duration ... ] INPUT -o OUTPUT
|
||||
webpmux -info INPUT
|
||||
webpmux [-h|-help]
|
||||
webpmux -version
|
||||
webpmux argument_file_name
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the webpmux command.
|
||||
|
||||
webpmux can be used to create/extract from animated WebP files, as well
|
||||
as to add/extract/strip XMP/EXIF metadata and ICC profile. If a single
|
||||
file name (not starting with the character '-') is supplied as the ar-
|
||||
gument, the command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number of argu-
|
||||
ments.
|
||||
|
||||
OPTIONS
|
||||
GET_OPTIONS (-get):
|
||||
icc Get ICC profile.
|
||||
|
||||
exif Get EXIF metadata.
|
||||
|
||||
xmp Get XMP metadata.
|
||||
|
||||
frame n
|
||||
Get nth frame from an animated image. (n = 0 has a special mean-
|
||||
ing: last frame).
|
||||
|
||||
|
||||
SET_OPTIONS (-set)
|
||||
loop loop_count
|
||||
Set loop count on an animated file.
|
||||
|
||||
Where: 'loop_count' must be in range [0, 65535].
|
||||
|
||||
bgcolor A,R,G,B
|
||||
Set the background color of the canvas on an animated file.
|
||||
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255 speci-
|
||||
fying the Alpha, Red, Green and Blue component values respectively.
|
||||
|
||||
icc file.icc
|
||||
Set ICC profile.
|
||||
|
||||
Where: 'file.icc' contains the ICC profile to be set.
|
||||
|
||||
exif file.exif
|
||||
Set EXIF metadata.
|
||||
|
||||
Where: 'file.exif' contains the EXIF metadata to be set.
|
||||
|
||||
xmp file.xmp
|
||||
Set XMP metadata.
|
||||
|
||||
Where: 'file.xmp' contains the XMP metadata to be set.
|
||||
|
||||
|
||||
STRIP_OPTIONS (-strip)
|
||||
icc Strip ICC profile.
|
||||
|
||||
exif Strip EXIF metadata.
|
||||
|
||||
xmp Strip XMP metadata.
|
||||
|
||||
|
||||
DURATION_OPTIONS (-duration)
|
||||
Amend the duration of a specific interval of frames. This option is
|
||||
only effective on animated WebP and has no effect on a single-frame
|
||||
file.
|
||||
|
||||
duration[,start[,end]]
|
||||
Where:
|
||||
duration is the duration for the interval in milliseconds
|
||||
(mandatory). Must be non-negative.
|
||||
start is the starting frame index of the interval (optional).
|
||||
end is the ending frame index (inclusive) of the interval (op-
|
||||
tional).
|
||||
|
||||
The three typical usages of this option are:
|
||||
-duration d
|
||||
set the duration to 'd' for the whole animation.
|
||||
-duration d,f
|
||||
set the duration of frame 'f' to 'd'.
|
||||
-duration d,start,end
|
||||
set the duration to 'd' for the whole [start,end] interval.
|
||||
|
||||
|
||||
Note that the frames outside of the [start, end] interval will
|
||||
remain untouched.
|
||||
The 'end' value '0' has the special meaning 'last frame of the
|
||||
animation'.
|
||||
|
||||
Reminder:
|
||||
frame indexing starts at '1'.
|
||||
|
||||
|
||||
FRAME_OPTIONS (-frame)
|
||||
Create an animated WebP file from multiple (non-animated) WebP images.
|
||||
|
||||
file_i +di[+xi+yi[+mi[bi]]]
|
||||
Where: 'file_i' is the i'th frame (WebP format), 'xi','yi' spec-
|
||||
ify the image offset for this frame, 'di' is the pause duration
|
||||
before next frame, 'mi' is the dispose method for this frame (0
|
||||
for NONE or 1 for BACKGROUND) and 'bi' is the blending method
|
||||
for this frame (+b for BLEND or -b for NO_BLEND). Argument 'bi'
|
||||
can be omitted and will default to +b (BLEND). Also, 'mi' can
|
||||
be omitted if 'bi' is omitted and will default to 0 (NONE). Fi-
|
||||
nally, if 'mi' and 'bi' are omitted then 'xi' and 'yi' can be
|
||||
omitted and will default to +0+0.
|
||||
|
||||
-loop n
|
||||
Loop the frames n number of times. 0 indicates the frames should
|
||||
loop forever. Valid range is 0 to 65535 [Default: 0 (infi-
|
||||
nite)].
|
||||
|
||||
-bgcolor A,R,G,B
|
||||
Background color of the canvas.
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values re-
|
||||
spectively [Default: 255,255,255,255].
|
||||
|
||||
|
||||
INPUT
|
||||
Input file in WebP format.
|
||||
|
||||
|
||||
OUTPUT (-o)
|
||||
Output file in WebP format.
|
||||
|
||||
|
||||
Note:
|
||||
The nature of EXIF, XMP and ICC data is not checked and is assumed to
|
||||
be valid.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
Add ICC profile:
|
||||
webpmux -set icc image_profile.icc in.webp -o icc_container.webp
|
||||
|
||||
Extract ICC profile:
|
||||
webpmux -get icc icc_container.webp -o image_profile.icc
|
||||
|
||||
Strip ICC profile:
|
||||
webpmux -strip icc icc_container.webp -o without_icc.webp
|
||||
|
||||
Add XMP metadata:
|
||||
webpmux -set xmp image_metadata.xmp in.webp -o xmp_container.webp
|
||||
|
||||
Extract XMP metadata:
|
||||
webpmux -get xmp xmp_container.webp -o image_metadata.xmp
|
||||
|
||||
Strip XMP metadata:
|
||||
webpmux -strip xmp xmp_container.webp -o without_xmp.webp
|
||||
|
||||
Add EXIF metadata:
|
||||
webpmux -set exif image_metadata.exif in.webp -o exif_container.webp
|
||||
|
||||
Extract EXIF metadata:
|
||||
webpmux -get exif exif_container.webp -o image_metadata.exif
|
||||
|
||||
Strip EXIF metadata:
|
||||
webpmux -strip exif exif_container.webp -o without_exif.webp
|
||||
|
||||
Create an animated WebP file from 3 (non-animated) WebP images:
|
||||
webpmux -frame 1.webp +100 -frame 2.webp +100+50+50
|
||||
-frame 3.webp +100+50+50+1+b -loop 10 -bgcolor 255,255,255,255
|
||||
-o anim_container.webp
|
||||
|
||||
Get the 2nd frame from an animated WebP file:
|
||||
webpmux -get frame 2 anim_container.webp -o frame_2.webp
|
||||
|
||||
Using -get/-set/-strip with input file name starting with '-':
|
||||
webpmux -set icc image_profile.icc -o icc_container.webp -- ---in.webp
|
||||
webpmux -get icc -o image_profile.icc -- ---icc_container.webp
|
||||
webpmux -strip icc -o without_icc.webp -- ---icc_container.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
webpmux is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Vikas Arora <vikaas.arora@gmail.com>,
|
||||
for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), dwebp(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 WEBPMUX(1)
|
||||
@@ -0,0 +1,503 @@
|
||||
// Copyright 2010 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Main decoding functions for WebP images.
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_DECODE_H_
|
||||
#define WEBP_WEBP_DECODE_H_
|
||||
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_DECODER_ABI_VERSION 0x0209 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum VP8StatusCode VP8StatusCode;
|
||||
// typedef enum WEBP_CSP_MODE WEBP_CSP_MODE;
|
||||
typedef struct WebPRGBABuffer WebPRGBABuffer;
|
||||
typedef struct WebPYUVABuffer WebPYUVABuffer;
|
||||
typedef struct WebPDecBuffer WebPDecBuffer;
|
||||
typedef struct WebPIDecoder WebPIDecoder;
|
||||
typedef struct WebPBitstreamFeatures WebPBitstreamFeatures;
|
||||
typedef struct WebPDecoderOptions WebPDecoderOptions;
|
||||
typedef struct WebPDecoderConfig WebPDecoderConfig;
|
||||
|
||||
// Return the decoder's version number, packed in hexadecimal using 8bits for
|
||||
// each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetDecoderVersion(void);
|
||||
|
||||
// Retrieve basic header information: width, height.
|
||||
// This function will also validate the header, returning true on success,
|
||||
// false otherwise. '*width' and '*height' are only valid on successful return.
|
||||
// Pointers 'width' and 'height' can be passed NULL if deemed irrelevant.
|
||||
// Note: The following chunk sequences (before the raw VP8/VP8L data) are
|
||||
// considered valid by this function:
|
||||
// RIFF + VP8(L)
|
||||
// RIFF + VP8X + (optional chunks) + VP8(L)
|
||||
// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
WEBP_EXTERN int WebPGetInfo(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Decodes WebP images pointed to by 'data' and returns RGBA samples, along
|
||||
// with the dimensions in *width and *height. The ordering of samples in
|
||||
// memory is R, G, B, A, R, G, B, A... in scan order (endian-independent).
|
||||
// The returned pointer should be deleted calling WebPFree().
|
||||
// Returns NULL in case of error.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBA(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning A, R, G, B, A, R, G, B... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeARGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning B, G, R, A, B, G, R, A... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRA(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning R, G, B, R, G, B... ordered data.
|
||||
// If the bitstream contains transparency, it is ignored.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGB, but returning B, G, R, B, G, R... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGR(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
|
||||
// Decode WebP images pointed to by 'data' to Y'UV format(*). The pointer
|
||||
// returned is the Y samples buffer. Upon return, *u and *v will point to
|
||||
// the U and V chroma data. These U and V buffers need NOT be passed to
|
||||
// WebPFree(), unlike the returned Y luma one. The dimension of the U and V
|
||||
// planes are both (*width + 1) / 2 and (*height + 1)/ 2.
|
||||
// Upon return, the Y buffer has a stride returned as '*stride', while U and V
|
||||
// have a common stride returned as '*uv_stride'.
|
||||
// Return NULL in case of error.
|
||||
// (*) Also named Y'CbCr. See: https://en.wikipedia.org/wiki/YCbCr
|
||||
WEBP_EXTERN uint8_t* WebPDecodeYUV(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height,
|
||||
uint8_t** u, uint8_t** v,
|
||||
int* stride, int* uv_stride);
|
||||
|
||||
// These five functions are variants of the above ones, that decode the image
|
||||
// directly into a pre-allocated buffer 'output_buffer'. The maximum storage
|
||||
// available in this buffer is indicated by 'output_buffer_size'. If this
|
||||
// storage is not sufficient (or an error occurred), NULL is returned.
|
||||
// Otherwise, output_buffer is returned, for convenience.
|
||||
// The parameter 'output_stride' specifies the distance (in bytes)
|
||||
// between scanlines. Hence, output_buffer_size is expected to be at least
|
||||
// output_stride x picture-height.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBAInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeARGBInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRAInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// RGB and BGR variants. Here too the transparency information, if present,
|
||||
// will be dropped and ignored.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// WebPDecodeYUVInto() is a variant of WebPDecodeYUV() that operates directly
|
||||
// into pre-allocated luma/chroma plane buffers. This function requires the
|
||||
// strides to be passed: one for the luma plane and one for each of the
|
||||
// chroma ones. The size of each plane buffer is passed as 'luma_size',
|
||||
// 'u_size' and 'v_size' respectively.
|
||||
// Pointer to the luma plane ('*luma') is returned or NULL if an error occurred
|
||||
// during decoding (or because some buffers were found to be too small).
|
||||
WEBP_EXTERN uint8_t* WebPDecodeYUVInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Output colorspaces and buffer
|
||||
|
||||
// Colorspaces
|
||||
// Note: the naming describes the byte-ordering of packed samples in memory.
|
||||
// For instance, MODE_BGRA relates to samples ordered as B,G,R,A,B,G,R,A,...
|
||||
// Non-capital names (e.g.:MODE_Argb) relates to pre-multiplied RGB channels.
|
||||
// RGBA-4444 and RGB-565 colorspaces are represented by following byte-order:
|
||||
// RGBA-4444: [r3 r2 r1 r0 g3 g2 g1 g0], [b3 b2 b1 b0 a3 a2 a1 a0], ...
|
||||
// RGB-565: [r4 r3 r2 r1 r0 g5 g4 g3], [g2 g1 g0 b4 b3 b2 b1 b0], ...
|
||||
// In the case WEBP_SWAP_16BITS_CSP is defined, the bytes are swapped for
|
||||
// these two modes:
|
||||
// RGBA-4444: [b3 b2 b1 b0 a3 a2 a1 a0], [r3 r2 r1 r0 g3 g2 g1 g0], ...
|
||||
// RGB-565: [g2 g1 g0 b4 b3 b2 b1 b0], [r4 r3 r2 r1 r0 g5 g4 g3], ...
|
||||
|
||||
typedef enum WEBP_CSP_MODE {
|
||||
MODE_RGB = 0, MODE_RGBA = 1,
|
||||
MODE_BGR = 2, MODE_BGRA = 3,
|
||||
MODE_ARGB = 4, MODE_RGBA_4444 = 5,
|
||||
MODE_RGB_565 = 6,
|
||||
// RGB-premultiplied transparent modes (alpha value is preserved)
|
||||
MODE_rgbA = 7,
|
||||
MODE_bgrA = 8,
|
||||
MODE_Argb = 9,
|
||||
MODE_rgbA_4444 = 10,
|
||||
// YUV modes must come after RGB ones.
|
||||
MODE_YUV = 11, MODE_YUVA = 12, // yuv 4:2:0
|
||||
MODE_LAST = 13
|
||||
} WEBP_CSP_MODE;
|
||||
|
||||
// Some useful macros:
|
||||
static WEBP_INLINE int WebPIsPremultipliedMode(WEBP_CSP_MODE mode) {
|
||||
return (mode == MODE_rgbA || mode == MODE_bgrA || mode == MODE_Argb ||
|
||||
mode == MODE_rgbA_4444);
|
||||
}
|
||||
|
||||
static WEBP_INLINE int WebPIsAlphaMode(WEBP_CSP_MODE mode) {
|
||||
return (mode == MODE_RGBA || mode == MODE_BGRA || mode == MODE_ARGB ||
|
||||
mode == MODE_RGBA_4444 || mode == MODE_YUVA ||
|
||||
WebPIsPremultipliedMode(mode));
|
||||
}
|
||||
|
||||
static WEBP_INLINE int WebPIsRGBMode(WEBP_CSP_MODE mode) {
|
||||
return (mode < MODE_YUV);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPDecBuffer: Generic structure for describing the output sample buffer.
|
||||
|
||||
struct WebPRGBABuffer { // view as RGBA
|
||||
uint8_t* rgba; // pointer to RGBA samples
|
||||
int stride; // stride in bytes from one scanline to the next.
|
||||
size_t size; // total size of the *rgba buffer.
|
||||
};
|
||||
|
||||
struct WebPYUVABuffer { // view as YUVA
|
||||
uint8_t* y, *u, *v, *a; // pointer to luma, chroma U/V, alpha samples
|
||||
int y_stride; // luma stride
|
||||
int u_stride, v_stride; // chroma strides
|
||||
int a_stride; // alpha stride
|
||||
size_t y_size; // luma plane size
|
||||
size_t u_size, v_size; // chroma planes size
|
||||
size_t a_size; // alpha-plane size
|
||||
};
|
||||
|
||||
// Output buffer
|
||||
struct WebPDecBuffer {
|
||||
WEBP_CSP_MODE colorspace; // Colorspace.
|
||||
int width, height; // Dimensions.
|
||||
int is_external_memory; // If non-zero, 'internal_memory' pointer is not
|
||||
// used. If value is '2' or more, the external
|
||||
// memory is considered 'slow' and multiple
|
||||
// read/write will be avoided.
|
||||
union {
|
||||
WebPRGBABuffer RGBA;
|
||||
WebPYUVABuffer YUVA;
|
||||
} u; // Nameless union of buffer parameters.
|
||||
uint32_t pad[4]; // padding for later use
|
||||
|
||||
uint8_t* private_memory; // Internally allocated memory (only when
|
||||
// is_external_memory is 0). Should not be used
|
||||
// externally, but accessed via the buffer union.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPInitDecBufferInternal(WebPDecBuffer*, int);
|
||||
|
||||
// Initialize the structure as empty. Must be called before any other use.
|
||||
// Returns false in case of version mismatch
|
||||
static WEBP_INLINE int WebPInitDecBuffer(WebPDecBuffer* buffer) {
|
||||
return WebPInitDecBufferInternal(buffer, WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Free any memory associated with the buffer. Must always be called last.
|
||||
// Note: doesn't free the 'buffer' structure itself.
|
||||
WEBP_EXTERN void WebPFreeDecBuffer(WebPDecBuffer* buffer);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Enumeration of the status codes
|
||||
|
||||
typedef enum VP8StatusCode {
|
||||
VP8_STATUS_OK = 0,
|
||||
VP8_STATUS_OUT_OF_MEMORY,
|
||||
VP8_STATUS_INVALID_PARAM,
|
||||
VP8_STATUS_BITSTREAM_ERROR,
|
||||
VP8_STATUS_UNSUPPORTED_FEATURE,
|
||||
VP8_STATUS_SUSPENDED,
|
||||
VP8_STATUS_USER_ABORT,
|
||||
VP8_STATUS_NOT_ENOUGH_DATA
|
||||
} VP8StatusCode;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Incremental decoding
|
||||
//
|
||||
// This API allows streamlined decoding of partial data.
|
||||
// Picture can be incrementally decoded as data become available thanks to the
|
||||
// WebPIDecoder object. This object can be left in a SUSPENDED state if the
|
||||
// picture is only partially decoded, pending additional input.
|
||||
// Code example:
|
||||
//
|
||||
// WebPInitDecBuffer(&output_buffer);
|
||||
// output_buffer.colorspace = mode;
|
||||
// ...
|
||||
// WebPIDecoder* idec = WebPINewDecoder(&output_buffer);
|
||||
// while (additional_data_is_available) {
|
||||
// // ... (get additional data in some new_data[] buffer)
|
||||
// status = WebPIAppend(idec, new_data, new_data_size);
|
||||
// if (status != VP8_STATUS_OK && status != VP8_STATUS_SUSPENDED) {
|
||||
// break; // an error occurred.
|
||||
// }
|
||||
//
|
||||
// // The above call decodes the current available buffer.
|
||||
// // Part of the image can now be refreshed by calling
|
||||
// // WebPIDecGetRGB()/WebPIDecGetYUVA() etc.
|
||||
// }
|
||||
// WebPIDelete(idec);
|
||||
|
||||
// Creates a new incremental decoder with the supplied buffer parameter.
|
||||
// This output_buffer can be passed NULL, in which case a default output buffer
|
||||
// is used (with MODE_RGB). Otherwise, an internal reference to 'output_buffer'
|
||||
// is kept, which means that the lifespan of 'output_buffer' must be larger than
|
||||
// that of the returned WebPIDecoder object.
|
||||
// The supplied 'output_buffer' content MUST NOT be changed between calls to
|
||||
// WebPIAppend() or WebPIUpdate() unless 'output_buffer.is_external_memory' is
|
||||
// not set to 0. In such a case, it is allowed to modify the pointers, size and
|
||||
// stride of output_buffer.u.RGBA or output_buffer.u.YUVA, provided they remain
|
||||
// within valid bounds.
|
||||
// All other fields of WebPDecBuffer MUST remain constant between calls.
|
||||
// Returns NULL if the allocation failed.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewDecoder(WebPDecBuffer* output_buffer);
|
||||
|
||||
// This function allocates and initializes an incremental-decoder object, which
|
||||
// will output the RGB/A samples specified by 'csp' into a preallocated
|
||||
// buffer 'output_buffer'. The size of this buffer is at least
|
||||
// 'output_buffer_size' and the stride (distance in bytes between two scanlines)
|
||||
// is specified by 'output_stride'.
|
||||
// Additionally, output_buffer can be passed NULL in which case the output
|
||||
// buffer will be allocated automatically when the decoding starts. The
|
||||
// colorspace 'csp' is taken into account for allocating this buffer. All other
|
||||
// parameters are ignored.
|
||||
// Returns NULL if the allocation failed, or if some parameters are invalid.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewRGB(
|
||||
WEBP_CSP_MODE csp,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// This function allocates and initializes an incremental-decoder object, which
|
||||
// will output the raw luma/chroma samples into a preallocated planes if
|
||||
// supplied. The luma plane is specified by its pointer 'luma', its size
|
||||
// 'luma_size' and its stride 'luma_stride'. Similarly, the chroma-u plane
|
||||
// is specified by the 'u', 'u_size' and 'u_stride' parameters, and the chroma-v
|
||||
// plane by 'v' and 'v_size'. And same for the alpha-plane. The 'a' pointer
|
||||
// can be pass NULL in case one is not interested in the transparency plane.
|
||||
// Conversely, 'luma' can be passed NULL if no preallocated planes are supplied.
|
||||
// In this case, the output buffer will be automatically allocated (using
|
||||
// MODE_YUVA) when decoding starts. All parameters are then ignored.
|
||||
// Returns NULL if the allocation failed or if a parameter is invalid.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewYUVA(
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride,
|
||||
uint8_t* a, size_t a_size, int a_stride);
|
||||
|
||||
// Deprecated version of the above, without the alpha plane.
|
||||
// Kept for backward compatibility.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewYUV(
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride);
|
||||
|
||||
// Deletes the WebPIDecoder object and associated memory. Must always be called
|
||||
// if WebPINewDecoder, WebPINewRGB or WebPINewYUV succeeded.
|
||||
WEBP_EXTERN void WebPIDelete(WebPIDecoder* idec);
|
||||
|
||||
// Copies and decodes the next available data. Returns VP8_STATUS_OK when
|
||||
// the image is successfully decoded. Returns VP8_STATUS_SUSPENDED when more
|
||||
// data is expected. Returns error in other cases.
|
||||
WEBP_EXTERN VP8StatusCode WebPIAppend(
|
||||
WebPIDecoder* idec, const uint8_t* data, size_t data_size);
|
||||
|
||||
// A variant of the above function to be used when data buffer contains
|
||||
// partial data from the beginning. In this case data buffer is not copied
|
||||
// to the internal memory.
|
||||
// Note that the value of the 'data' pointer can change between calls to
|
||||
// WebPIUpdate, for instance when the data buffer is resized to fit larger data.
|
||||
WEBP_EXTERN VP8StatusCode WebPIUpdate(
|
||||
WebPIDecoder* idec, const uint8_t* data, size_t data_size);
|
||||
|
||||
// Returns the RGB/A image decoded so far. Returns NULL if output params
|
||||
// are not initialized yet. The RGB/A output type corresponds to the colorspace
|
||||
// specified during call to WebPINewDecoder() or WebPINewRGB().
|
||||
// *last_y is the index of last decoded row in raster scan order. Some pointers
|
||||
// (*last_y, *width etc.) can be NULL if corresponding information is not
|
||||
// needed. The values in these pointers are only valid on successful (non-NULL)
|
||||
// return.
|
||||
WEBP_EXTERN uint8_t* WebPIDecGetRGB(
|
||||
const WebPIDecoder* idec, int* last_y,
|
||||
int* width, int* height, int* stride);
|
||||
|
||||
// Same as above function to get a YUVA image. Returns pointer to the luma
|
||||
// plane or NULL in case of error. If there is no alpha information
|
||||
// the alpha pointer '*a' will be returned NULL.
|
||||
WEBP_EXTERN uint8_t* WebPIDecGetYUVA(
|
||||
const WebPIDecoder* idec, int* last_y,
|
||||
uint8_t** u, uint8_t** v, uint8_t** a,
|
||||
int* width, int* height, int* stride, int* uv_stride, int* a_stride);
|
||||
|
||||
// Deprecated alpha-less version of WebPIDecGetYUVA(): it will ignore the
|
||||
// alpha information (if present). Kept for backward compatibility.
|
||||
static WEBP_INLINE uint8_t* WebPIDecGetYUV(
|
||||
const WebPIDecoder* idec, int* last_y, uint8_t** u, uint8_t** v,
|
||||
int* width, int* height, int* stride, int* uv_stride) {
|
||||
return WebPIDecGetYUVA(idec, last_y, u, v, NULL, width, height,
|
||||
stride, uv_stride, NULL);
|
||||
}
|
||||
|
||||
// Generic call to retrieve information about the displayable area.
|
||||
// If non NULL, the left/right/width/height pointers are filled with the visible
|
||||
// rectangular area so far.
|
||||
// Returns NULL in case the incremental decoder object is in an invalid state.
|
||||
// Otherwise returns the pointer to the internal representation. This structure
|
||||
// is read-only, tied to WebPIDecoder's lifespan and should not be modified.
|
||||
WEBP_EXTERN const WebPDecBuffer* WebPIDecodedArea(
|
||||
const WebPIDecoder* idec, int* left, int* top, int* width, int* height);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Advanced decoding parametrization
|
||||
//
|
||||
// Code sample for using the advanced decoding API
|
||||
/*
|
||||
// A) Init a configuration object
|
||||
WebPDecoderConfig config;
|
||||
CHECK(WebPInitDecoderConfig(&config));
|
||||
|
||||
// B) optional: retrieve the bitstream's features.
|
||||
CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
|
||||
|
||||
// C) Adjust 'config', if needed
|
||||
config.no_fancy_upsampling = 1;
|
||||
config.output.colorspace = MODE_BGRA;
|
||||
// etc.
|
||||
|
||||
// Note that you can also make config.output point to an externally
|
||||
// supplied memory buffer, provided it's big enough to store the decoded
|
||||
// picture. Otherwise, config.output will just be used to allocate memory
|
||||
// and store the decoded picture.
|
||||
|
||||
// D) Decode!
|
||||
CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
|
||||
|
||||
// E) Decoded image is now in config.output (and config.output.u.RGBA)
|
||||
|
||||
// F) Reclaim memory allocated in config's object. It's safe to call
|
||||
// this function even if the memory is external and wasn't allocated
|
||||
// by WebPDecode().
|
||||
WebPFreeDecBuffer(&config.output);
|
||||
*/
|
||||
|
||||
// Features gathered from the bitstream
|
||||
struct WebPBitstreamFeatures {
|
||||
int width; // Width in pixels, as read from the bitstream.
|
||||
int height; // Height in pixels, as read from the bitstream.
|
||||
int has_alpha; // True if the bitstream contains an alpha channel.
|
||||
int has_animation; // True if the bitstream is an animation.
|
||||
int format; // 0 = undefined (/mixed), 1 = lossy, 2 = lossless
|
||||
|
||||
uint32_t pad[5]; // padding for later use
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN VP8StatusCode WebPGetFeaturesInternal(
|
||||
const uint8_t*, size_t, WebPBitstreamFeatures*, int);
|
||||
|
||||
// Retrieve features from the bitstream. The *features structure is filled
|
||||
// with information gathered from the bitstream.
|
||||
// Returns VP8_STATUS_OK when the features are successfully retrieved. Returns
|
||||
// VP8_STATUS_NOT_ENOUGH_DATA when more data is needed to retrieve the
|
||||
// features from headers. Returns error in other cases.
|
||||
// Note: The following chunk sequences (before the raw VP8/VP8L data) are
|
||||
// considered valid by this function:
|
||||
// RIFF + VP8(L)
|
||||
// RIFF + VP8X + (optional chunks) + VP8(L)
|
||||
// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
static WEBP_INLINE VP8StatusCode WebPGetFeatures(
|
||||
const uint8_t* data, size_t data_size,
|
||||
WebPBitstreamFeatures* features) {
|
||||
return WebPGetFeaturesInternal(data, data_size, features,
|
||||
WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Decoding options
|
||||
struct WebPDecoderOptions {
|
||||
int bypass_filtering; // if true, skip the in-loop filtering
|
||||
int no_fancy_upsampling; // if true, use faster pointwise upsampler
|
||||
int use_cropping; // if true, cropping is applied _first_
|
||||
int crop_left, crop_top; // top-left position for cropping.
|
||||
// Will be snapped to even values.
|
||||
int crop_width, crop_height; // dimension of the cropping area
|
||||
int use_scaling; // if true, scaling is applied _afterward_
|
||||
int scaled_width, scaled_height; // final resolution
|
||||
int use_threads; // if true, use multi-threaded decoding
|
||||
int dithering_strength; // dithering strength (0=Off, 100=full)
|
||||
int flip; // if true, flip output vertically
|
||||
int alpha_dithering_strength; // alpha dithering strength in [0..100]
|
||||
|
||||
uint32_t pad[5]; // padding for later use
|
||||
};
|
||||
|
||||
// Main object storing the configuration for advanced decoding.
|
||||
struct WebPDecoderConfig {
|
||||
WebPBitstreamFeatures input; // Immutable bitstream features (optional)
|
||||
WebPDecBuffer output; // Output buffer (can point to external mem)
|
||||
WebPDecoderOptions options; // Decoding options
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPInitDecoderConfigInternal(WebPDecoderConfig*, int);
|
||||
|
||||
// Initialize the configuration as empty. This function must always be
|
||||
// called first, unless WebPGetFeatures() is to be called.
|
||||
// Returns false in case of mismatched version.
|
||||
static WEBP_INLINE int WebPInitDecoderConfig(WebPDecoderConfig* config) {
|
||||
return WebPInitDecoderConfigInternal(config, WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Instantiate a new incremental decoder object with the requested
|
||||
// configuration. The bitstream can be passed using 'data' and 'data_size'
|
||||
// parameter, in which case the features will be parsed and stored into
|
||||
// config->input. Otherwise, 'data' can be NULL and no parsing will occur.
|
||||
// Note that 'config' can be NULL too, in which case a default configuration
|
||||
// is used. If 'config' is not NULL, it must outlive the WebPIDecoder object
|
||||
// as some references to its fields will be used. No internal copy of 'config'
|
||||
// is made.
|
||||
// The return WebPIDecoder object must always be deleted calling WebPIDelete().
|
||||
// Returns NULL in case of error (and config->status will then reflect
|
||||
// the error condition, if available).
|
||||
WEBP_EXTERN WebPIDecoder* WebPIDecode(const uint8_t* data, size_t data_size,
|
||||
WebPDecoderConfig* config);
|
||||
|
||||
// Non-incremental version. This version decodes the full data at once, taking
|
||||
// 'config' into account. Returns decoding status (which should be VP8_STATUS_OK
|
||||
// if the decoding was successful). Note that 'config' cannot be NULL.
|
||||
WEBP_EXTERN VP8StatusCode WebPDecode(const uint8_t* data, size_t data_size,
|
||||
WebPDecoderConfig* config);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_DECODE_H_
|
||||
@@ -0,0 +1,363 @@
|
||||
// Copyright 2012 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Demux API.
|
||||
// Enables extraction of image and extended format data from WebP files.
|
||||
|
||||
// Code Example: Demuxing WebP data to extract all the frames, ICC profile
|
||||
// and EXIF/XMP metadata.
|
||||
/*
|
||||
WebPDemuxer* demux = WebPDemux(&webp_data);
|
||||
|
||||
uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
|
||||
uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
|
||||
// ... (Get information about the features present in the WebP file).
|
||||
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
|
||||
|
||||
// ... (Iterate over all frames).
|
||||
WebPIterator iter;
|
||||
if (WebPDemuxGetFrame(demux, 1, &iter)) {
|
||||
do {
|
||||
// ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
|
||||
// ... and get other frame properties like width, height, offsets etc.
|
||||
// ... see 'struct WebPIterator' below for more info).
|
||||
} while (WebPDemuxNextFrame(&iter));
|
||||
WebPDemuxReleaseIterator(&iter);
|
||||
}
|
||||
|
||||
// ... (Extract metadata).
|
||||
WebPChunkIterator chunk_iter;
|
||||
if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
|
||||
// ... (Consume the ICC profile in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
|
||||
// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
|
||||
// ... (Consume the XMP metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
WebPDemuxDelete(demux);
|
||||
*/
|
||||
|
||||
#ifndef WEBP_WEBP_DEMUX_H_
|
||||
#define WEBP_WEBP_DEMUX_H_
|
||||
|
||||
#include "./decode.h" // for WEBP_CSP_MODE
|
||||
#include "./mux_types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_DEMUX_ABI_VERSION 0x0107 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPDemuxState WebPDemuxState;
|
||||
// typedef enum WebPFormatFeature WebPFormatFeature;
|
||||
typedef struct WebPDemuxer WebPDemuxer;
|
||||
typedef struct WebPIterator WebPIterator;
|
||||
typedef struct WebPChunkIterator WebPChunkIterator;
|
||||
typedef struct WebPAnimInfo WebPAnimInfo;
|
||||
typedef struct WebPAnimDecoderOptions WebPAnimDecoderOptions;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// Returns the version number of the demux library, packed in hexadecimal using
|
||||
// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetDemuxVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Life of a Demux object
|
||||
|
||||
typedef enum WebPDemuxState {
|
||||
WEBP_DEMUX_PARSE_ERROR = -1, // An error occurred while parsing.
|
||||
WEBP_DEMUX_PARSING_HEADER = 0, // Not enough data to parse full header.
|
||||
WEBP_DEMUX_PARSED_HEADER = 1, // Header parsing complete,
|
||||
// data may be available.
|
||||
WEBP_DEMUX_DONE = 2 // Entire file has been parsed.
|
||||
} WebPDemuxState;
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPDemuxer* WebPDemuxInternal(
|
||||
const WebPData*, int, WebPDemuxState*, int);
|
||||
|
||||
// Parses the full WebP file given by 'data'. For single images the WebP file
|
||||
// header alone or the file header and the chunk header may be absent.
|
||||
// Returns a WebPDemuxer object on successful parse, NULL otherwise.
|
||||
static WEBP_INLINE WebPDemuxer* WebPDemux(const WebPData* data) {
|
||||
return WebPDemuxInternal(data, 0, NULL, WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Parses the possibly incomplete WebP file given by 'data'.
|
||||
// If 'state' is non-NULL it will be set to indicate the status of the demuxer.
|
||||
// Returns NULL in case of error or if there isn't enough data to start parsing;
|
||||
// and a WebPDemuxer object on successful parse.
|
||||
// Note that WebPDemuxer keeps internal pointers to 'data' memory segment.
|
||||
// If this data is volatile, the demuxer object should be deleted (by calling
|
||||
// WebPDemuxDelete()) and WebPDemuxPartial() called again on the new data.
|
||||
// This is usually an inexpensive operation.
|
||||
static WEBP_INLINE WebPDemuxer* WebPDemuxPartial(
|
||||
const WebPData* data, WebPDemuxState* state) {
|
||||
return WebPDemuxInternal(data, 1, state, WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Frees memory associated with 'dmux'.
|
||||
WEBP_EXTERN void WebPDemuxDelete(WebPDemuxer* dmux);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Data/information extraction.
|
||||
|
||||
typedef enum WebPFormatFeature {
|
||||
WEBP_FF_FORMAT_FLAGS, // bit-wise combination of WebPFeatureFlags
|
||||
// corresponding to the 'VP8X' chunk (if present).
|
||||
WEBP_FF_CANVAS_WIDTH,
|
||||
WEBP_FF_CANVAS_HEIGHT,
|
||||
WEBP_FF_LOOP_COUNT, // only relevant for animated file
|
||||
WEBP_FF_BACKGROUND_COLOR, // idem.
|
||||
WEBP_FF_FRAME_COUNT // Number of frames present in the demux object.
|
||||
// In case of a partial demux, this is the number
|
||||
// of frames seen so far, with the last frame
|
||||
// possibly being partial.
|
||||
} WebPFormatFeature;
|
||||
|
||||
// Get the 'feature' value from the 'dmux'.
|
||||
// NOTE: values are only valid if WebPDemux() was used or WebPDemuxPartial()
|
||||
// returned a state > WEBP_DEMUX_PARSING_HEADER.
|
||||
// If 'feature' is WEBP_FF_FORMAT_FLAGS, the returned value is a bit-wise
|
||||
// combination of WebPFeatureFlags values.
|
||||
// If 'feature' is WEBP_FF_LOOP_COUNT, WEBP_FF_BACKGROUND_COLOR, the returned
|
||||
// value is only meaningful if the bitstream is animated.
|
||||
WEBP_EXTERN uint32_t WebPDemuxGetI(
|
||||
const WebPDemuxer* dmux, WebPFormatFeature feature);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Frame iteration.
|
||||
|
||||
struct WebPIterator {
|
||||
int frame_num;
|
||||
int num_frames; // equivalent to WEBP_FF_FRAME_COUNT.
|
||||
int x_offset, y_offset; // offset relative to the canvas.
|
||||
int width, height; // dimensions of this frame.
|
||||
int duration; // display duration in milliseconds.
|
||||
WebPMuxAnimDispose dispose_method; // dispose method for the frame.
|
||||
int complete; // true if 'fragment' contains a full frame. partial images
|
||||
// may still be decoded with the WebP incremental decoder.
|
||||
WebPData fragment; // The frame given by 'frame_num'. Note for historical
|
||||
// reasons this is called a fragment.
|
||||
int has_alpha; // True if the frame contains transparency.
|
||||
WebPMuxAnimBlend blend_method; // Blend operation for the frame.
|
||||
|
||||
uint32_t pad[2]; // padding for later use.
|
||||
void* private_; // for internal use only.
|
||||
};
|
||||
|
||||
// Retrieves frame 'frame_number' from 'dmux'.
|
||||
// 'iter->fragment' points to the frame on return from this function.
|
||||
// Setting 'frame_number' equal to 0 will return the last frame of the image.
|
||||
// Returns false if 'dmux' is NULL or frame 'frame_number' is not present.
|
||||
// Call WebPDemuxReleaseIterator() when use of the iterator is complete.
|
||||
// NOTE: 'dmux' must persist for the lifetime of 'iter'.
|
||||
WEBP_EXTERN int WebPDemuxGetFrame(
|
||||
const WebPDemuxer* dmux, int frame_number, WebPIterator* iter);
|
||||
|
||||
// Sets 'iter->fragment' to point to the next ('iter->frame_num' + 1) or
|
||||
// previous ('iter->frame_num' - 1) frame. These functions do not loop.
|
||||
// Returns true on success, false otherwise.
|
||||
WEBP_EXTERN int WebPDemuxNextFrame(WebPIterator* iter);
|
||||
WEBP_EXTERN int WebPDemuxPrevFrame(WebPIterator* iter);
|
||||
|
||||
// Releases any memory associated with 'iter'.
|
||||
// Must be called before any subsequent calls to WebPDemuxGetChunk() on the same
|
||||
// iter. Also, must be called before destroying the associated WebPDemuxer with
|
||||
// WebPDemuxDelete().
|
||||
WEBP_EXTERN void WebPDemuxReleaseIterator(WebPIterator* iter);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Chunk iteration.
|
||||
|
||||
struct WebPChunkIterator {
|
||||
// The current and total number of chunks with the fourcc given to
|
||||
// WebPDemuxGetChunk().
|
||||
int chunk_num;
|
||||
int num_chunks;
|
||||
WebPData chunk; // The payload of the chunk.
|
||||
|
||||
uint32_t pad[6]; // padding for later use
|
||||
void* private_;
|
||||
};
|
||||
|
||||
// Retrieves the 'chunk_number' instance of the chunk with id 'fourcc' from
|
||||
// 'dmux'.
|
||||
// 'fourcc' is a character array containing the fourcc of the chunk to return,
|
||||
// e.g., "ICCP", "XMP ", "EXIF", etc.
|
||||
// Setting 'chunk_number' equal to 0 will return the last chunk in a set.
|
||||
// Returns true if the chunk is found, false otherwise. Image related chunk
|
||||
// payloads are accessed through WebPDemuxGetFrame() and related functions.
|
||||
// Call WebPDemuxReleaseChunkIterator() when use of the iterator is complete.
|
||||
// NOTE: 'dmux' must persist for the lifetime of the iterator.
|
||||
WEBP_EXTERN int WebPDemuxGetChunk(const WebPDemuxer* dmux,
|
||||
const char fourcc[4], int chunk_number,
|
||||
WebPChunkIterator* iter);
|
||||
|
||||
// Sets 'iter->chunk' to point to the next ('iter->chunk_num' + 1) or previous
|
||||
// ('iter->chunk_num' - 1) chunk. These functions do not loop.
|
||||
// Returns true on success, false otherwise.
|
||||
WEBP_EXTERN int WebPDemuxNextChunk(WebPChunkIterator* iter);
|
||||
WEBP_EXTERN int WebPDemuxPrevChunk(WebPChunkIterator* iter);
|
||||
|
||||
// Releases any memory associated with 'iter'.
|
||||
// Must be called before destroying the associated WebPDemuxer with
|
||||
// WebPDemuxDelete().
|
||||
WEBP_EXTERN void WebPDemuxReleaseChunkIterator(WebPChunkIterator* iter);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPAnimDecoder API
|
||||
//
|
||||
// This API allows decoding (possibly) animated WebP images.
|
||||
//
|
||||
// Code Example:
|
||||
/*
|
||||
WebPAnimDecoderOptions dec_options;
|
||||
WebPAnimDecoderOptionsInit(&dec_options);
|
||||
// Tune 'dec_options' as needed.
|
||||
WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
|
||||
WebPAnimInfo anim_info;
|
||||
WebPAnimDecoderGetInfo(dec, &anim_info);
|
||||
for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
|
||||
while (WebPAnimDecoderHasMoreFrames(dec)) {
|
||||
uint8_t* buf;
|
||||
int timestamp;
|
||||
WebPAnimDecoderGetNext(dec, &buf, ×tamp);
|
||||
// ... (Render 'buf' based on 'timestamp').
|
||||
// ... (Do NOT free 'buf', as it is owned by 'dec').
|
||||
}
|
||||
WebPAnimDecoderReset(dec);
|
||||
}
|
||||
const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
|
||||
// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
|
||||
WebPAnimDecoderDelete(dec);
|
||||
*/
|
||||
|
||||
typedef struct WebPAnimDecoder WebPAnimDecoder; // Main opaque object.
|
||||
|
||||
// Global options.
|
||||
struct WebPAnimDecoderOptions {
|
||||
// Output colorspace. Only the following modes are supported:
|
||||
// MODE_RGBA, MODE_BGRA, MODE_rgbA and MODE_bgrA.
|
||||
WEBP_CSP_MODE color_mode;
|
||||
int use_threads; // If true, use multi-threaded decoding.
|
||||
uint32_t padding[7]; // Padding for later use.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN int WebPAnimDecoderOptionsInitInternal(
|
||||
WebPAnimDecoderOptions*, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPAnimDecoderOptions
|
||||
// structure before modification. Returns false in case of version mismatch.
|
||||
// WebPAnimDecoderOptionsInit() must have succeeded before using the
|
||||
// 'dec_options' object.
|
||||
static WEBP_INLINE int WebPAnimDecoderOptionsInit(
|
||||
WebPAnimDecoderOptions* dec_options) {
|
||||
return WebPAnimDecoderOptionsInitInternal(dec_options,
|
||||
WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN WebPAnimDecoder* WebPAnimDecoderNewInternal(
|
||||
const WebPData*, const WebPAnimDecoderOptions*, int);
|
||||
|
||||
// Creates and initializes a WebPAnimDecoder object.
|
||||
// Parameters:
|
||||
// webp_data - (in) WebP bitstream. This should remain unchanged during the
|
||||
// lifetime of the output WebPAnimDecoder object.
|
||||
// dec_options - (in) decoding options. Can be passed NULL to choose
|
||||
// reasonable defaults (in particular, color mode MODE_RGBA
|
||||
// will be picked).
|
||||
// Returns:
|
||||
// A pointer to the newly created WebPAnimDecoder object, or NULL in case of
|
||||
// parsing error, invalid option or memory error.
|
||||
static WEBP_INLINE WebPAnimDecoder* WebPAnimDecoderNew(
|
||||
const WebPData* webp_data, const WebPAnimDecoderOptions* dec_options) {
|
||||
return WebPAnimDecoderNewInternal(webp_data, dec_options,
|
||||
WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Global information about the animation..
|
||||
struct WebPAnimInfo {
|
||||
uint32_t canvas_width;
|
||||
uint32_t canvas_height;
|
||||
uint32_t loop_count;
|
||||
uint32_t bgcolor;
|
||||
uint32_t frame_count;
|
||||
uint32_t pad[4]; // padding for later use
|
||||
};
|
||||
|
||||
// Get global information about the animation.
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance to get information from.
|
||||
// info - (out) global information fetched from the animation.
|
||||
// Returns:
|
||||
// True on success.
|
||||
WEBP_EXTERN int WebPAnimDecoderGetInfo(const WebPAnimDecoder* dec,
|
||||
WebPAnimInfo* info);
|
||||
|
||||
// Fetch the next frame from 'dec' based on options supplied to
|
||||
// WebPAnimDecoderNew(). This will be a fully reconstructed canvas of size
|
||||
// 'canvas_width * 4 * canvas_height', and not just the frame sub-rectangle. The
|
||||
// returned buffer 'buf' is valid only until the next call to
|
||||
// WebPAnimDecoderGetNext(), WebPAnimDecoderReset() or WebPAnimDecoderDelete().
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance from which the next frame is to be fetched.
|
||||
// buf - (out) decoded frame.
|
||||
// timestamp - (out) timestamp of the frame in milliseconds.
|
||||
// Returns:
|
||||
// False if any of the arguments are NULL, or if there is a parsing or
|
||||
// decoding error, or if there are no more frames. Otherwise, returns true.
|
||||
WEBP_EXTERN int WebPAnimDecoderGetNext(WebPAnimDecoder* dec,
|
||||
uint8_t** buf, int* timestamp);
|
||||
|
||||
// Check if there are more frames left to decode.
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance to be checked.
|
||||
// Returns:
|
||||
// True if 'dec' is not NULL and some frames are yet to be decoded.
|
||||
// Otherwise, returns false.
|
||||
WEBP_EXTERN int WebPAnimDecoderHasMoreFrames(const WebPAnimDecoder* dec);
|
||||
|
||||
// Resets the WebPAnimDecoder object, so that next call to
|
||||
// WebPAnimDecoderGetNext() will restart decoding from 1st frame. This would be
|
||||
// helpful when all frames need to be decoded multiple times (e.g.
|
||||
// info.loop_count times) without destroying and recreating the 'dec' object.
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance to be reset
|
||||
WEBP_EXTERN void WebPAnimDecoderReset(WebPAnimDecoder* dec);
|
||||
|
||||
// Grab the internal demuxer object.
|
||||
// Getting the demuxer object can be useful if one wants to use operations only
|
||||
// available through demuxer; e.g. to get XMP/EXIF/ICC metadata. The returned
|
||||
// demuxer object is owned by 'dec' and is valid only until the next call to
|
||||
// WebPAnimDecoderDelete().
|
||||
//
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance from which the demuxer object is to be fetched.
|
||||
WEBP_EXTERN const WebPDemuxer* WebPAnimDecoderGetDemuxer(
|
||||
const WebPAnimDecoder* dec);
|
||||
|
||||
// Deletes the WebPAnimDecoder object.
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance to be deleted
|
||||
WEBP_EXTERN void WebPAnimDecoderDelete(WebPAnimDecoder* dec);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_DEMUX_H_
|
||||
@@ -0,0 +1,552 @@
|
||||
// Copyright 2011 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// WebP encoder: main interface
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_ENCODE_H_
|
||||
#define WEBP_WEBP_ENCODE_H_
|
||||
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_ENCODER_ABI_VERSION 0x020f // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPImageHint WebPImageHint;
|
||||
// typedef enum WebPEncCSP WebPEncCSP;
|
||||
// typedef enum WebPPreset WebPPreset;
|
||||
// typedef enum WebPEncodingError WebPEncodingError;
|
||||
typedef struct WebPConfig WebPConfig;
|
||||
typedef struct WebPPicture WebPPicture; // main structure for I/O
|
||||
typedef struct WebPAuxStats WebPAuxStats;
|
||||
typedef struct WebPMemoryWriter WebPMemoryWriter;
|
||||
|
||||
// Return the encoder's version number, packed in hexadecimal using 8bits for
|
||||
// each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetEncoderVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// One-stop-shop call! No questions asked:
|
||||
|
||||
// Returns the size of the compressed data (pointed to by *output), or 0 if
|
||||
// an error occurred. The compressed data must be released by the caller
|
||||
// using the call 'WebPFree(*output)'.
|
||||
// These functions compress using the lossy format, and the quality_factor
|
||||
// can go from 0 (smaller output, lower quality) to 100 (best quality,
|
||||
// larger output).
|
||||
WEBP_EXTERN size_t WebPEncodeRGB(const uint8_t* rgb,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeBGR(const uint8_t* bgr,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeRGBA(const uint8_t* rgba,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeBGRA(const uint8_t* bgra,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
|
||||
// These functions are the equivalent of the above, but compressing in a
|
||||
// lossless manner. Files are usually larger than lossy format, but will
|
||||
// not suffer any compression loss.
|
||||
// Note these functions, like the lossy versions, use the library's default
|
||||
// settings. For lossless this means 'exact' is disabled. RGB values in
|
||||
// transparent areas will be modified to improve compression. To avoid this,
|
||||
// use WebPEncode() and set WebPConfig::exact to 1.
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessRGB(const uint8_t* rgb,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessBGR(const uint8_t* bgr,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessRGBA(const uint8_t* rgba,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessBGRA(const uint8_t* bgra,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Coding parameters
|
||||
|
||||
// Image characteristics hint for the underlying encoder.
|
||||
typedef enum WebPImageHint {
|
||||
WEBP_HINT_DEFAULT = 0, // default preset.
|
||||
WEBP_HINT_PICTURE, // digital picture, like portrait, inner shot
|
||||
WEBP_HINT_PHOTO, // outdoor photograph, with natural lighting
|
||||
WEBP_HINT_GRAPH, // Discrete tone image (graph, map-tile etc).
|
||||
WEBP_HINT_LAST
|
||||
} WebPImageHint;
|
||||
|
||||
// Compression parameters.
|
||||
struct WebPConfig {
|
||||
int lossless; // Lossless encoding (0=lossy(default), 1=lossless).
|
||||
float quality; // between 0 and 100. For lossy, 0 gives the smallest
|
||||
// size and 100 the largest. For lossless, this
|
||||
// parameter is the amount of effort put into the
|
||||
// compression: 0 is the fastest but gives larger
|
||||
// files compared to the slowest, but best, 100.
|
||||
int method; // quality/speed trade-off (0=fast, 6=slower-better)
|
||||
|
||||
WebPImageHint image_hint; // Hint for image type (lossless only for now).
|
||||
|
||||
int target_size; // if non-zero, set the desired target size in bytes.
|
||||
// Takes precedence over the 'compression' parameter.
|
||||
float target_PSNR; // if non-zero, specifies the minimal distortion to
|
||||
// try to achieve. Takes precedence over target_size.
|
||||
int segments; // maximum number of segments to use, in [1..4]
|
||||
int sns_strength; // Spatial Noise Shaping. 0=off, 100=maximum.
|
||||
int filter_strength; // range: [0 = off .. 100 = strongest]
|
||||
int filter_sharpness; // range: [0 = off .. 7 = least sharp]
|
||||
int filter_type; // filtering type: 0 = simple, 1 = strong (only used
|
||||
// if filter_strength > 0 or autofilter > 0)
|
||||
int autofilter; // Auto adjust filter's strength [0 = off, 1 = on]
|
||||
int alpha_compression; // Algorithm for encoding the alpha plane (0 = none,
|
||||
// 1 = compressed with WebP lossless). Default is 1.
|
||||
int alpha_filtering; // Predictive filtering method for alpha plane.
|
||||
// 0: none, 1: fast, 2: best. Default if 1.
|
||||
int alpha_quality; // Between 0 (smallest size) and 100 (lossless).
|
||||
// Default is 100.
|
||||
int pass; // number of entropy-analysis passes (in [1..10]).
|
||||
|
||||
int show_compressed; // if true, export the compressed picture back.
|
||||
// In-loop filtering is not applied.
|
||||
int preprocessing; // preprocessing filter:
|
||||
// 0=none, 1=segment-smooth, 2=pseudo-random dithering
|
||||
int partitions; // log2(number of token partitions) in [0..3]. Default
|
||||
// is set to 0 for easier progressive decoding.
|
||||
int partition_limit; // quality degradation allowed to fit the 512k limit
|
||||
// on prediction modes coding (0: no degradation,
|
||||
// 100: maximum possible degradation).
|
||||
int emulate_jpeg_size; // If true, compression parameters will be remapped
|
||||
// to better match the expected output size from
|
||||
// JPEG compression. Generally, the output size will
|
||||
// be similar but the degradation will be lower.
|
||||
int thread_level; // If non-zero, try and use multi-threaded encoding.
|
||||
int low_memory; // If set, reduce memory usage (but increase CPU use).
|
||||
|
||||
int near_lossless; // Near lossless encoding [0 = max loss .. 100 = off
|
||||
// (default)].
|
||||
int exact; // if non-zero, preserve the exact RGB values under
|
||||
// transparent area. Otherwise, discard this invisible
|
||||
// RGB information for better compression. The default
|
||||
// value is 0.
|
||||
|
||||
int use_delta_palette; // reserved for future lossless feature
|
||||
int use_sharp_yuv; // if needed, use sharp (and slow) RGB->YUV conversion
|
||||
|
||||
int qmin; // minimum permissible quality factor
|
||||
int qmax; // maximum permissible quality factor
|
||||
};
|
||||
|
||||
// Enumerate some predefined settings for WebPConfig, depending on the type
|
||||
// of source picture. These presets are used when calling WebPConfigPreset().
|
||||
typedef enum WebPPreset {
|
||||
WEBP_PRESET_DEFAULT = 0, // default preset.
|
||||
WEBP_PRESET_PICTURE, // digital picture, like portrait, inner shot
|
||||
WEBP_PRESET_PHOTO, // outdoor photograph, with natural lighting
|
||||
WEBP_PRESET_DRAWING, // hand or line drawing, with high-contrast details
|
||||
WEBP_PRESET_ICON, // small-sized colorful images
|
||||
WEBP_PRESET_TEXT // text-like
|
||||
} WebPPreset;
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPConfigInitInternal(WebPConfig*, WebPPreset, float, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPConfig structure before
|
||||
// modification. Returns false in case of version mismatch. WebPConfigInit()
|
||||
// must have succeeded before using the 'config' object.
|
||||
// Note that the default values are lossless=0 and quality=75.
|
||||
static WEBP_INLINE int WebPConfigInit(WebPConfig* config) {
|
||||
return WebPConfigInitInternal(config, WEBP_PRESET_DEFAULT, 75.f,
|
||||
WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// This function will initialize the configuration according to a predefined
|
||||
// set of parameters (referred to by 'preset') and a given quality factor.
|
||||
// This function can be called as a replacement to WebPConfigInit(). Will
|
||||
// return false in case of error.
|
||||
static WEBP_INLINE int WebPConfigPreset(WebPConfig* config,
|
||||
WebPPreset preset, float quality) {
|
||||
return WebPConfigInitInternal(config, preset, quality,
|
||||
WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Activate the lossless compression mode with the desired efficiency level
|
||||
// between 0 (fastest, lowest compression) and 9 (slower, best compression).
|
||||
// A good default level is '6', providing a fair tradeoff between compression
|
||||
// speed and final compressed size.
|
||||
// This function will overwrite several fields from config: 'method', 'quality'
|
||||
// and 'lossless'. Returns false in case of parameter error.
|
||||
WEBP_EXTERN int WebPConfigLosslessPreset(WebPConfig* config, int level);
|
||||
|
||||
// Returns true if 'config' is non-NULL and all configuration parameters are
|
||||
// within their valid ranges.
|
||||
WEBP_EXTERN int WebPValidateConfig(const WebPConfig* config);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Input / Output
|
||||
// Structure for storing auxiliary statistics.
|
||||
|
||||
struct WebPAuxStats {
|
||||
int coded_size; // final size
|
||||
|
||||
float PSNR[5]; // peak-signal-to-noise ratio for Y/U/V/All/Alpha
|
||||
int block_count[3]; // number of intra4/intra16/skipped macroblocks
|
||||
int header_bytes[2]; // approximate number of bytes spent for header
|
||||
// and mode-partition #0
|
||||
int residual_bytes[3][4]; // approximate number of bytes spent for
|
||||
// DC/AC/uv coefficients for each (0..3) segments.
|
||||
int segment_size[4]; // number of macroblocks in each segments
|
||||
int segment_quant[4]; // quantizer values for each segments
|
||||
int segment_level[4]; // filtering strength for each segments [0..63]
|
||||
|
||||
int alpha_data_size; // size of the transparency data
|
||||
int layer_data_size; // size of the enhancement layer data
|
||||
|
||||
// lossless encoder statistics
|
||||
uint32_t lossless_features; // bit0:predictor bit1:cross-color transform
|
||||
// bit2:subtract-green bit3:color indexing
|
||||
int histogram_bits; // number of precision bits of histogram
|
||||
int transform_bits; // precision bits for transform
|
||||
int cache_bits; // number of bits for color cache lookup
|
||||
int palette_size; // number of color in palette, if used
|
||||
int lossless_size; // final lossless size
|
||||
int lossless_hdr_size; // lossless header (transform, huffman etc) size
|
||||
int lossless_data_size; // lossless image data size
|
||||
|
||||
uint32_t pad[2]; // padding for later use
|
||||
};
|
||||
|
||||
// Signature for output function. Should return true if writing was successful.
|
||||
// data/data_size is the segment of data to write, and 'picture' is for
|
||||
// reference (and so one can make use of picture->custom_ptr).
|
||||
typedef int (*WebPWriterFunction)(const uint8_t* data, size_t data_size,
|
||||
const WebPPicture* picture);
|
||||
|
||||
// WebPMemoryWrite: a special WebPWriterFunction that writes to memory using
|
||||
// the following WebPMemoryWriter object (to be set as a custom_ptr).
|
||||
struct WebPMemoryWriter {
|
||||
uint8_t* mem; // final buffer (of size 'max_size', larger than 'size').
|
||||
size_t size; // final size
|
||||
size_t max_size; // total capacity
|
||||
uint32_t pad[1]; // padding for later use
|
||||
};
|
||||
|
||||
// The following must be called first before any use.
|
||||
WEBP_EXTERN void WebPMemoryWriterInit(WebPMemoryWriter* writer);
|
||||
|
||||
// The following must be called to deallocate writer->mem memory. The 'writer'
|
||||
// object itself is not deallocated.
|
||||
WEBP_EXTERN void WebPMemoryWriterClear(WebPMemoryWriter* writer);
|
||||
// The custom writer to be used with WebPMemoryWriter as custom_ptr. Upon
|
||||
// completion, writer.mem and writer.size will hold the coded data.
|
||||
// writer.mem must be freed by calling WebPMemoryWriterClear.
|
||||
WEBP_EXTERN int WebPMemoryWrite(const uint8_t* data, size_t data_size,
|
||||
const WebPPicture* picture);
|
||||
|
||||
// Progress hook, called from time to time to report progress. It can return
|
||||
// false to request an abort of the encoding process, or true otherwise if
|
||||
// everything is OK.
|
||||
typedef int (*WebPProgressHook)(int percent, const WebPPicture* picture);
|
||||
|
||||
// Color spaces.
|
||||
typedef enum WebPEncCSP {
|
||||
// chroma sampling
|
||||
WEBP_YUV420 = 0, // 4:2:0
|
||||
WEBP_YUV420A = 4, // alpha channel variant
|
||||
WEBP_CSP_UV_MASK = 3, // bit-mask to get the UV sampling factors
|
||||
WEBP_CSP_ALPHA_BIT = 4 // bit that is set if alpha is present
|
||||
} WebPEncCSP;
|
||||
|
||||
// Encoding error conditions.
|
||||
typedef enum WebPEncodingError {
|
||||
VP8_ENC_OK = 0,
|
||||
VP8_ENC_ERROR_OUT_OF_MEMORY, // memory error allocating objects
|
||||
VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY, // memory error while flushing bits
|
||||
VP8_ENC_ERROR_NULL_PARAMETER, // a pointer parameter is NULL
|
||||
VP8_ENC_ERROR_INVALID_CONFIGURATION, // configuration is invalid
|
||||
VP8_ENC_ERROR_BAD_DIMENSION, // picture has invalid width/height
|
||||
VP8_ENC_ERROR_PARTITION0_OVERFLOW, // partition is bigger than 512k
|
||||
VP8_ENC_ERROR_PARTITION_OVERFLOW, // partition is bigger than 16M
|
||||
VP8_ENC_ERROR_BAD_WRITE, // error while flushing bytes
|
||||
VP8_ENC_ERROR_FILE_TOO_BIG, // file is bigger than 4G
|
||||
VP8_ENC_ERROR_USER_ABORT, // abort request by user
|
||||
VP8_ENC_ERROR_LAST // list terminator. always last.
|
||||
} WebPEncodingError;
|
||||
|
||||
// maximum width/height allowed (inclusive), in pixels
|
||||
#define WEBP_MAX_DIMENSION 16383
|
||||
|
||||
// Main exchange structure (input samples, output bytes, statistics)
|
||||
//
|
||||
// Once WebPPictureInit() has been called, it's ok to make all the INPUT fields
|
||||
// (use_argb, y/u/v, argb, ...) point to user-owned data, even if
|
||||
// WebPPictureAlloc() has been called. Depending on the value use_argb,
|
||||
// it's guaranteed that either *argb or *y/*u/*v content will be kept untouched.
|
||||
struct WebPPicture {
|
||||
// INPUT
|
||||
//////////////
|
||||
// Main flag for encoder selecting between ARGB or YUV input.
|
||||
// It is recommended to use ARGB input (*argb, argb_stride) for lossless
|
||||
// compression, and YUV input (*y, *u, *v, etc.) for lossy compression
|
||||
// since these are the respective native colorspace for these formats.
|
||||
int use_argb;
|
||||
|
||||
// YUV input (mostly used for input to lossy compression)
|
||||
WebPEncCSP colorspace; // colorspace: should be YUV420 for now (=Y'CbCr).
|
||||
int width, height; // dimensions (less or equal to WEBP_MAX_DIMENSION)
|
||||
uint8_t* y, *u, *v; // pointers to luma/chroma planes.
|
||||
int y_stride, uv_stride; // luma/chroma strides.
|
||||
uint8_t* a; // pointer to the alpha plane
|
||||
int a_stride; // stride of the alpha plane
|
||||
uint32_t pad1[2]; // padding for later use
|
||||
|
||||
// ARGB input (mostly used for input to lossless compression)
|
||||
uint32_t* argb; // Pointer to argb (32 bit) plane.
|
||||
int argb_stride; // This is stride in pixels units, not bytes.
|
||||
uint32_t pad2[3]; // padding for later use
|
||||
|
||||
// OUTPUT
|
||||
///////////////
|
||||
// Byte-emission hook, to store compressed bytes as they are ready.
|
||||
WebPWriterFunction writer; // can be NULL
|
||||
void* custom_ptr; // can be used by the writer.
|
||||
|
||||
// map for extra information (only for lossy compression mode)
|
||||
int extra_info_type; // 1: intra type, 2: segment, 3: quant
|
||||
// 4: intra-16 prediction mode,
|
||||
// 5: chroma prediction mode,
|
||||
// 6: bit cost, 7: distortion
|
||||
uint8_t* extra_info; // if not NULL, points to an array of size
|
||||
// ((width + 15) / 16) * ((height + 15) / 16) that
|
||||
// will be filled with a macroblock map, depending
|
||||
// on extra_info_type.
|
||||
|
||||
// STATS AND REPORTS
|
||||
///////////////////////////
|
||||
// Pointer to side statistics (updated only if not NULL)
|
||||
WebPAuxStats* stats;
|
||||
|
||||
// Error code for the latest error encountered during encoding
|
||||
WebPEncodingError error_code;
|
||||
|
||||
// If not NULL, report progress during encoding.
|
||||
WebPProgressHook progress_hook;
|
||||
|
||||
void* user_data; // this field is free to be set to any value and
|
||||
// used during callbacks (like progress-report e.g.).
|
||||
|
||||
uint32_t pad3[3]; // padding for later use
|
||||
|
||||
// Unused for now
|
||||
uint8_t* pad4, *pad5;
|
||||
uint32_t pad6[8]; // padding for later use
|
||||
|
||||
// PRIVATE FIELDS
|
||||
////////////////////
|
||||
void* memory_; // row chunk of memory for yuva planes
|
||||
void* memory_argb_; // and for argb too.
|
||||
void* pad7[2]; // padding for later use
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPPictureInitInternal(WebPPicture*, int);
|
||||
|
||||
// Should always be called, to initialize the structure. Returns false in case
|
||||
// of version mismatch. WebPPictureInit() must have succeeded before using the
|
||||
// 'picture' object.
|
||||
// Note that, by default, use_argb is false and colorspace is WEBP_YUV420.
|
||||
static WEBP_INLINE int WebPPictureInit(WebPPicture* picture) {
|
||||
return WebPPictureInitInternal(picture, WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPPicture utils
|
||||
|
||||
// Convenience allocation / deallocation based on picture->width/height:
|
||||
// Allocate y/u/v buffers as per colorspace/width/height specification.
|
||||
// Note! This function will free the previous buffer if needed.
|
||||
// Returns false in case of memory error.
|
||||
WEBP_EXTERN int WebPPictureAlloc(WebPPicture* picture);
|
||||
|
||||
// Release the memory allocated by WebPPictureAlloc() or WebPPictureImport*().
|
||||
// Note that this function does _not_ free the memory used by the 'picture'
|
||||
// object itself.
|
||||
// Besides memory (which is reclaimed) all other fields of 'picture' are
|
||||
// preserved.
|
||||
WEBP_EXTERN void WebPPictureFree(WebPPicture* picture);
|
||||
|
||||
// Copy the pixels of *src into *dst, using WebPPictureAlloc. Upon return, *dst
|
||||
// will fully own the copied pixels (this is not a view). The 'dst' picture need
|
||||
// not be initialized as its content is overwritten.
|
||||
// Returns false in case of memory allocation error.
|
||||
WEBP_EXTERN int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst);
|
||||
|
||||
// Compute the single distortion for packed planes of samples.
|
||||
// 'src' will be compared to 'ref', and the raw distortion stored into
|
||||
// '*distortion'. The refined metric (log(MSE), log(1 - ssim),...' will be
|
||||
// stored in '*result'.
|
||||
// 'x_step' is the horizontal stride (in bytes) between samples.
|
||||
// 'src/ref_stride' is the byte distance between rows.
|
||||
// Returns false in case of error (bad parameter, memory allocation error, ...).
|
||||
WEBP_EXTERN int WebPPlaneDistortion(const uint8_t* src, size_t src_stride,
|
||||
const uint8_t* ref, size_t ref_stride,
|
||||
int width, int height,
|
||||
size_t x_step,
|
||||
int type, // 0 = PSNR, 1 = SSIM, 2 = LSIM
|
||||
float* distortion, float* result);
|
||||
|
||||
// Compute PSNR, SSIM or LSIM distortion metric between two pictures. Results
|
||||
// are in dB, stored in result[] in the B/G/R/A/All order. The distortion is
|
||||
// always performed using ARGB samples. Hence if the input is YUV(A), the
|
||||
// picture will be internally converted to ARGB (just for the measurement).
|
||||
// Warning: this function is rather CPU-intensive.
|
||||
WEBP_EXTERN int WebPPictureDistortion(
|
||||
const WebPPicture* src, const WebPPicture* ref,
|
||||
int metric_type, // 0 = PSNR, 1 = SSIM, 2 = LSIM
|
||||
float result[5]);
|
||||
|
||||
// self-crops a picture to the rectangle defined by top/left/width/height.
|
||||
// Returns false in case of memory allocation error, or if the rectangle is
|
||||
// outside of the source picture.
|
||||
// The rectangle for the view is defined by the top-left corner pixel
|
||||
// coordinates (left, top) as well as its width and height. This rectangle
|
||||
// must be fully be comprised inside the 'src' source picture. If the source
|
||||
// picture uses the YUV420 colorspace, the top and left coordinates will be
|
||||
// snapped to even values.
|
||||
WEBP_EXTERN int WebPPictureCrop(WebPPicture* picture,
|
||||
int left, int top, int width, int height);
|
||||
|
||||
// Extracts a view from 'src' picture into 'dst'. The rectangle for the view
|
||||
// is defined by the top-left corner pixel coordinates (left, top) as well
|
||||
// as its width and height. This rectangle must be fully be comprised inside
|
||||
// the 'src' source picture. If the source picture uses the YUV420 colorspace,
|
||||
// the top and left coordinates will be snapped to even values.
|
||||
// Picture 'src' must out-live 'dst' picture. Self-extraction of view is allowed
|
||||
// ('src' equal to 'dst') as a mean of fast-cropping (but note that doing so,
|
||||
// the original dimension will be lost). Picture 'dst' need not be initialized
|
||||
// with WebPPictureInit() if it is different from 'src', since its content will
|
||||
// be overwritten.
|
||||
// Returns false in case of invalid parameters.
|
||||
WEBP_EXTERN int WebPPictureView(const WebPPicture* src,
|
||||
int left, int top, int width, int height,
|
||||
WebPPicture* dst);
|
||||
|
||||
// Returns true if the 'picture' is actually a view and therefore does
|
||||
// not own the memory for pixels.
|
||||
WEBP_EXTERN int WebPPictureIsView(const WebPPicture* picture);
|
||||
|
||||
// Rescale a picture to new dimension width x height.
|
||||
// If either 'width' or 'height' (but not both) is 0 the corresponding
|
||||
// dimension will be calculated preserving the aspect ratio.
|
||||
// No gamma correction is applied.
|
||||
// Returns false in case of error (invalid parameter or insufficient memory).
|
||||
WEBP_EXTERN int WebPPictureRescale(WebPPicture* picture, int width, int height);
|
||||
|
||||
// Colorspace conversion function to import RGB samples.
|
||||
// Previous buffer will be free'd, if any.
|
||||
// *rgb buffer should have a size of at least height * rgb_stride.
|
||||
// Returns false in case of memory error.
|
||||
WEBP_EXTERN int WebPPictureImportRGB(
|
||||
WebPPicture* picture, const uint8_t* rgb, int rgb_stride);
|
||||
// Same, but for RGBA buffer.
|
||||
WEBP_EXTERN int WebPPictureImportRGBA(
|
||||
WebPPicture* picture, const uint8_t* rgba, int rgba_stride);
|
||||
// Same, but for RGBA buffer. Imports the RGB direct from the 32-bit format
|
||||
// input buffer ignoring the alpha channel. Avoids needing to copy the data
|
||||
// to a temporary 24-bit RGB buffer to import the RGB only.
|
||||
WEBP_EXTERN int WebPPictureImportRGBX(
|
||||
WebPPicture* picture, const uint8_t* rgbx, int rgbx_stride);
|
||||
|
||||
// Variants of the above, but taking BGR(A|X) input.
|
||||
WEBP_EXTERN int WebPPictureImportBGR(
|
||||
WebPPicture* picture, const uint8_t* bgr, int bgr_stride);
|
||||
WEBP_EXTERN int WebPPictureImportBGRA(
|
||||
WebPPicture* picture, const uint8_t* bgra, int bgra_stride);
|
||||
WEBP_EXTERN int WebPPictureImportBGRX(
|
||||
WebPPicture* picture, const uint8_t* bgrx, int bgrx_stride);
|
||||
|
||||
// Converts picture->argb data to the YUV420A format. The 'colorspace'
|
||||
// parameter is deprecated and should be equal to WEBP_YUV420.
|
||||
// Upon return, picture->use_argb is set to false. The presence of real
|
||||
// non-opaque transparent values is detected, and 'colorspace' will be
|
||||
// adjusted accordingly. Note that this method is lossy.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureARGBToYUVA(WebPPicture* picture,
|
||||
WebPEncCSP /*colorspace = WEBP_YUV420*/);
|
||||
|
||||
// Same as WebPPictureARGBToYUVA(), but the conversion is done using
|
||||
// pseudo-random dithering with a strength 'dithering' between
|
||||
// 0.0 (no dithering) and 1.0 (maximum dithering). This is useful
|
||||
// for photographic picture.
|
||||
WEBP_EXTERN int WebPPictureARGBToYUVADithered(
|
||||
WebPPicture* picture, WebPEncCSP colorspace, float dithering);
|
||||
|
||||
// Performs 'sharp' RGBA->YUVA420 downsampling and colorspace conversion.
|
||||
// Downsampling is handled with extra care in case of color clipping. This
|
||||
// method is roughly 2x slower than WebPPictureARGBToYUVA() but produces better
|
||||
// and sharper YUV representation.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureSharpARGBToYUVA(WebPPicture* picture);
|
||||
// kept for backward compatibility:
|
||||
WEBP_EXTERN int WebPPictureSmartARGBToYUVA(WebPPicture* picture);
|
||||
|
||||
// Converts picture->yuv to picture->argb and sets picture->use_argb to true.
|
||||
// The input format must be YUV_420 or YUV_420A. The conversion from YUV420 to
|
||||
// ARGB incurs a small loss too.
|
||||
// Note that the use of this colorspace is discouraged if one has access to the
|
||||
// raw ARGB samples, since using YUV420 is comparatively lossy.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureYUVAToARGB(WebPPicture* picture);
|
||||
|
||||
// Helper function: given a width x height plane of RGBA or YUV(A) samples
|
||||
// clean-up or smoothen the YUV or RGB samples under fully transparent area,
|
||||
// to help compressibility (no guarantee, though).
|
||||
WEBP_EXTERN void WebPCleanupTransparentArea(WebPPicture* picture);
|
||||
|
||||
// Scan the picture 'picture' for the presence of non fully opaque alpha values.
|
||||
// Returns true in such case. Otherwise returns false (indicating that the
|
||||
// alpha plane can be ignored altogether e.g.).
|
||||
WEBP_EXTERN int WebPPictureHasTransparency(const WebPPicture* picture);
|
||||
|
||||
// Remove the transparency information (if present) by blending the color with
|
||||
// the background color 'background_rgb' (specified as 24bit RGB triplet).
|
||||
// After this call, all alpha values are reset to 0xff.
|
||||
WEBP_EXTERN void WebPBlendAlpha(WebPPicture* picture, uint32_t background_rgb);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Main call
|
||||
|
||||
// Main encoding call, after config and picture have been initialized.
|
||||
// 'picture' must be less than 16384x16384 in dimension (cf WEBP_MAX_DIMENSION),
|
||||
// and the 'config' object must be a valid one.
|
||||
// Returns false in case of error, true otherwise.
|
||||
// In case of error, picture->error_code is updated accordingly.
|
||||
// 'picture' can hold the source samples in both YUV(A) or ARGB input, depending
|
||||
// on the value of 'picture->use_argb'. It is highly recommended to use
|
||||
// the former for lossy encoding, and the latter for lossless encoding
|
||||
// (when config.lossless is true). Automatic conversion from one format to
|
||||
// another is provided but they both incur some loss.
|
||||
WEBP_EXTERN int WebPEncode(const WebPConfig* config, WebPPicture* picture);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_ENCODE_H_
|
||||
@@ -0,0 +1,530 @@
|
||||
// Copyright 2011 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// RIFF container manipulation and encoding for WebP images.
|
||||
//
|
||||
// Authors: Urvang (urvang@google.com)
|
||||
// Vikas (vikasa@google.com)
|
||||
|
||||
#ifndef WEBP_WEBP_MUX_H_
|
||||
#define WEBP_WEBP_MUX_H_
|
||||
|
||||
#include "./mux_types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_MUX_ABI_VERSION 0x0108 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Mux API
|
||||
//
|
||||
// This API allows manipulation of WebP container images containing features
|
||||
// like color profile, metadata, animation.
|
||||
//
|
||||
// Code Example#1: Create a WebPMux object with image data, color profile and
|
||||
// XMP metadata.
|
||||
/*
|
||||
int copy_data = 0;
|
||||
WebPMux* mux = WebPMuxNew();
|
||||
// ... (Prepare image data).
|
||||
WebPMuxSetImage(mux, &image, copy_data);
|
||||
// ... (Prepare ICCP color profile data).
|
||||
WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
|
||||
// ... (Prepare XMP metadata).
|
||||
WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
|
||||
// Get data from mux in WebP RIFF format.
|
||||
WebPMuxAssemble(mux, &output_data);
|
||||
WebPMuxDelete(mux);
|
||||
// ... (Consume output_data; e.g. write output_data.bytes to file).
|
||||
WebPDataClear(&output_data);
|
||||
*/
|
||||
|
||||
// Code Example#2: Get image and color profile data from a WebP file.
|
||||
/*
|
||||
int copy_data = 0;
|
||||
// ... (Read data from file).
|
||||
WebPMux* mux = WebPMuxCreate(&data, copy_data);
|
||||
WebPMuxGetFrame(mux, 1, &image);
|
||||
// ... (Consume image; e.g. call WebPDecode() to decode the data).
|
||||
WebPMuxGetChunk(mux, "ICCP", &icc_profile);
|
||||
// ... (Consume icc_data).
|
||||
WebPMuxDelete(mux);
|
||||
WebPFree(data);
|
||||
*/
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPMuxError WebPMuxError;
|
||||
// typedef enum WebPChunkId WebPChunkId;
|
||||
typedef struct WebPMux WebPMux; // main opaque object.
|
||||
typedef struct WebPMuxFrameInfo WebPMuxFrameInfo;
|
||||
typedef struct WebPMuxAnimParams WebPMuxAnimParams;
|
||||
typedef struct WebPAnimEncoderOptions WebPAnimEncoderOptions;
|
||||
|
||||
// Error codes
|
||||
typedef enum WebPMuxError {
|
||||
WEBP_MUX_OK = 1,
|
||||
WEBP_MUX_NOT_FOUND = 0,
|
||||
WEBP_MUX_INVALID_ARGUMENT = -1,
|
||||
WEBP_MUX_BAD_DATA = -2,
|
||||
WEBP_MUX_MEMORY_ERROR = -3,
|
||||
WEBP_MUX_NOT_ENOUGH_DATA = -4
|
||||
} WebPMuxError;
|
||||
|
||||
// IDs for different types of chunks.
|
||||
typedef enum WebPChunkId {
|
||||
WEBP_CHUNK_VP8X, // VP8X
|
||||
WEBP_CHUNK_ICCP, // ICCP
|
||||
WEBP_CHUNK_ANIM, // ANIM
|
||||
WEBP_CHUNK_ANMF, // ANMF
|
||||
WEBP_CHUNK_DEPRECATED, // (deprecated from FRGM)
|
||||
WEBP_CHUNK_ALPHA, // ALPH
|
||||
WEBP_CHUNK_IMAGE, // VP8/VP8L
|
||||
WEBP_CHUNK_EXIF, // EXIF
|
||||
WEBP_CHUNK_XMP, // XMP
|
||||
WEBP_CHUNK_UNKNOWN, // Other chunks.
|
||||
WEBP_CHUNK_NIL
|
||||
} WebPChunkId;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// Returns the version number of the mux library, packed in hexadecimal using
|
||||
// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetMuxVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Life of a Mux object
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPMux* WebPNewInternal(int);
|
||||
|
||||
// Creates an empty mux object.
|
||||
// Returns:
|
||||
// A pointer to the newly created empty mux object.
|
||||
// Or NULL in case of memory error.
|
||||
static WEBP_INLINE WebPMux* WebPMuxNew(void) {
|
||||
return WebPNewInternal(WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Deletes the mux object.
|
||||
// Parameters:
|
||||
// mux - (in/out) object to be deleted
|
||||
WEBP_EXTERN void WebPMuxDelete(WebPMux* mux);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Mux creation.
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPMux* WebPMuxCreateInternal(const WebPData*, int, int);
|
||||
|
||||
// Creates a mux object from raw data given in WebP RIFF format.
|
||||
// Parameters:
|
||||
// bitstream - (in) the bitstream data in WebP RIFF format
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// A pointer to the mux object created from given data - on success.
|
||||
// NULL - In case of invalid data or memory error.
|
||||
static WEBP_INLINE WebPMux* WebPMuxCreate(const WebPData* bitstream,
|
||||
int copy_data) {
|
||||
return WebPMuxCreateInternal(bitstream, copy_data, WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Non-image chunks.
|
||||
|
||||
// Note: Only non-image related chunks should be managed through chunk APIs.
|
||||
// (Image related chunks are: "ANMF", "VP8 ", "VP8L" and "ALPH").
|
||||
// To add, get and delete images, use WebPMuxSetImage(), WebPMuxPushFrame(),
|
||||
// WebPMuxGetFrame() and WebPMuxDeleteFrame().
|
||||
|
||||
// Adds a chunk with id 'fourcc' and data 'chunk_data' in the mux object.
|
||||
// Any existing chunk(s) with the same id will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object to which the chunk is to be added
|
||||
// fourcc - (in) a character array containing the fourcc of the given chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// chunk_data - (in) the chunk data to be added
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetChunk(
|
||||
WebPMux* mux, const char fourcc[4], const WebPData* chunk_data,
|
||||
int copy_data);
|
||||
|
||||
// Gets a reference to the data of the chunk with id 'fourcc' in the mux object.
|
||||
// The caller should NOT free the returned data.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the chunk data is to be fetched
|
||||
// fourcc - (in) a character array containing the fourcc of the chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// chunk_data - (out) returned chunk data
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given id.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetChunk(
|
||||
const WebPMux* mux, const char fourcc[4], WebPData* chunk_data);
|
||||
|
||||
// Deletes the chunk with the given 'fourcc' from the mux object.
|
||||
// Parameters:
|
||||
// mux - (in/out) object from which the chunk is to be deleted
|
||||
// fourcc - (in) a character array containing the fourcc of the chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or fourcc is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given fourcc.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxDeleteChunk(
|
||||
WebPMux* mux, const char fourcc[4]);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Images.
|
||||
|
||||
// Encapsulates data about a single frame.
|
||||
struct WebPMuxFrameInfo {
|
||||
WebPData bitstream; // image data: can be a raw VP8/VP8L bitstream
|
||||
// or a single-image WebP file.
|
||||
int x_offset; // x-offset of the frame.
|
||||
int y_offset; // y-offset of the frame.
|
||||
int duration; // duration of the frame (in milliseconds).
|
||||
|
||||
WebPChunkId id; // frame type: should be one of WEBP_CHUNK_ANMF
|
||||
// or WEBP_CHUNK_IMAGE
|
||||
WebPMuxAnimDispose dispose_method; // Disposal method for the frame.
|
||||
WebPMuxAnimBlend blend_method; // Blend operation for the frame.
|
||||
uint32_t pad[1]; // padding for later use
|
||||
};
|
||||
|
||||
// Sets the (non-animated) image in the mux object.
|
||||
// Note: Any existing images (including frames) will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object in which the image is to be set
|
||||
// bitstream - (in) can be a raw VP8/VP8L bitstream or a single-image
|
||||
// WebP file (non-animated)
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL or bitstream is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetImage(
|
||||
WebPMux* mux, const WebPData* bitstream, int copy_data);
|
||||
|
||||
// Adds a frame at the end of the mux object.
|
||||
// Notes: (1) frame.id should be WEBP_CHUNK_ANMF
|
||||
// (2) For setting a non-animated image, use WebPMuxSetImage() instead.
|
||||
// (3) Type of frame being pushed must be same as the frames in mux.
|
||||
// (4) As WebP only supports even offsets, any odd offset will be snapped
|
||||
// to an even location using: offset &= ~1
|
||||
// Parameters:
|
||||
// mux - (in/out) object to which the frame is to be added
|
||||
// frame - (in) frame data.
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL
|
||||
// or if content of 'frame' is invalid.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxPushFrame(
|
||||
WebPMux* mux, const WebPMuxFrameInfo* frame, int copy_data);
|
||||
|
||||
// Gets the nth frame from the mux object.
|
||||
// The content of 'frame->bitstream' is allocated using WebPMalloc(), and NOT
|
||||
// owned by the 'mux' object. It MUST be deallocated by the caller by calling
|
||||
// WebPDataClear().
|
||||
// nth=0 has a special meaning - last position.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the info is to be fetched
|
||||
// nth - (in) index of the frame in the mux object
|
||||
// frame - (out) data of the returned frame
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - if there are less than nth frames in the mux object.
|
||||
// WEBP_MUX_BAD_DATA - if nth frame chunk in mux is invalid.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetFrame(
|
||||
const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame);
|
||||
|
||||
// Deletes a frame from the mux object.
|
||||
// nth=0 has a special meaning - last position.
|
||||
// Parameters:
|
||||
// mux - (in/out) object from which a frame is to be deleted
|
||||
// nth - (in) The position from which the frame is to be deleted
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - If there are less than nth frames in the mux object
|
||||
// before deletion.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxDeleteFrame(WebPMux* mux, uint32_t nth);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Animation.
|
||||
|
||||
// Animation parameters.
|
||||
struct WebPMuxAnimParams {
|
||||
uint32_t bgcolor; // Background color of the canvas stored (in MSB order) as:
|
||||
// Bits 00 to 07: Alpha.
|
||||
// Bits 08 to 15: Red.
|
||||
// Bits 16 to 23: Green.
|
||||
// Bits 24 to 31: Blue.
|
||||
int loop_count; // Number of times to repeat the animation [0 = infinite].
|
||||
};
|
||||
|
||||
// Sets the animation parameters in the mux object. Any existing ANIM chunks
|
||||
// will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object in which ANIM chunk is to be set/added
|
||||
// params - (in) animation parameters.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetAnimationParams(
|
||||
WebPMux* mux, const WebPMuxAnimParams* params);
|
||||
|
||||
// Gets the animation parameters from the mux object.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the animation parameters to be fetched
|
||||
// params - (out) animation parameters extracted from the ANIM chunk
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - if ANIM chunk is not present in mux object.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetAnimationParams(
|
||||
const WebPMux* mux, WebPMuxAnimParams* params);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Misc Utilities.
|
||||
|
||||
// Sets the canvas size for the mux object. The width and height can be
|
||||
// specified explicitly or left as zero (0, 0).
|
||||
// * When width and height are specified explicitly, then this frame bound is
|
||||
// enforced during subsequent calls to WebPMuxAssemble() and an error is
|
||||
// reported if any animated frame does not completely fit within the canvas.
|
||||
// * When unspecified (0, 0), the constructed canvas will get the frame bounds
|
||||
// from the bounding-box over all frames after calling WebPMuxAssemble().
|
||||
// Parameters:
|
||||
// mux - (in) object to which the canvas size is to be set
|
||||
// width - (in) canvas width
|
||||
// height - (in) canvas height
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL; or
|
||||
// width or height are invalid or out of bounds
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetCanvasSize(WebPMux* mux,
|
||||
int width, int height);
|
||||
|
||||
// Gets the canvas size from the mux object.
|
||||
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
|
||||
// That is, the mux object hasn't been modified since the last call to
|
||||
// WebPMuxAssemble() or WebPMuxCreate().
|
||||
// Parameters:
|
||||
// mux - (in) object from which the canvas size is to be fetched
|
||||
// width - (out) canvas width
|
||||
// height - (out) canvas height
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, width or height is NULL.
|
||||
// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetCanvasSize(const WebPMux* mux,
|
||||
int* width, int* height);
|
||||
|
||||
// Gets the feature flags from the mux object.
|
||||
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
|
||||
// That is, the mux object hasn't been modified since the last call to
|
||||
// WebPMuxAssemble() or WebPMuxCreate().
|
||||
// Parameters:
|
||||
// mux - (in) object from which the features are to be fetched
|
||||
// flags - (out) the flags specifying which features are present in the
|
||||
// mux object. This will be an OR of various flag values.
|
||||
// Enum 'WebPFeatureFlags' can be used to test individual flag values.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or flags is NULL.
|
||||
// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetFeatures(const WebPMux* mux,
|
||||
uint32_t* flags);
|
||||
|
||||
// Gets number of chunks with the given 'id' in the mux object.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the info is to be fetched
|
||||
// id - (in) chunk id specifying the type of chunk
|
||||
// num_elements - (out) number of chunks with the given chunk id
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, or num_elements is NULL.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxNumChunks(const WebPMux* mux,
|
||||
WebPChunkId id, int* num_elements);
|
||||
|
||||
// Assembles all chunks in WebP RIFF format and returns in 'assembled_data'.
|
||||
// This function also validates the mux object.
|
||||
// Note: The content of 'assembled_data' will be ignored and overwritten.
|
||||
// Also, the content of 'assembled_data' is allocated using WebPMalloc(), and
|
||||
// NOT owned by the 'mux' object. It MUST be deallocated by the caller by
|
||||
// calling WebPDataClear(). It's always safe to call WebPDataClear() upon
|
||||
// return, even in case of error.
|
||||
// Parameters:
|
||||
// mux - (in/out) object whose chunks are to be assembled
|
||||
// assembled_data - (out) assembled WebP data
|
||||
// Returns:
|
||||
// WEBP_MUX_BAD_DATA - if mux object is invalid.
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or assembled_data is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxAssemble(WebPMux* mux,
|
||||
WebPData* assembled_data);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPAnimEncoder API
|
||||
//
|
||||
// This API allows encoding (possibly) animated WebP images.
|
||||
//
|
||||
// Code Example:
|
||||
/*
|
||||
WebPAnimEncoderOptions enc_options;
|
||||
WebPAnimEncoderOptionsInit(&enc_options);
|
||||
// Tune 'enc_options' as needed.
|
||||
WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
|
||||
while(<there are more frames>) {
|
||||
WebPConfig config;
|
||||
WebPConfigInit(&config);
|
||||
// Tune 'config' as needed.
|
||||
WebPAnimEncoderAdd(enc, frame, timestamp_ms, &config);
|
||||
}
|
||||
WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
|
||||
WebPAnimEncoderAssemble(enc, webp_data);
|
||||
WebPAnimEncoderDelete(enc);
|
||||
// Write the 'webp_data' to a file, or re-mux it further.
|
||||
*/
|
||||
|
||||
typedef struct WebPAnimEncoder WebPAnimEncoder; // Main opaque object.
|
||||
|
||||
// Forward declarations. Defined in encode.h.
|
||||
struct WebPPicture;
|
||||
struct WebPConfig;
|
||||
|
||||
// Global options.
|
||||
struct WebPAnimEncoderOptions {
|
||||
WebPMuxAnimParams anim_params; // Animation parameters.
|
||||
int minimize_size; // If true, minimize the output size (slow). Implicitly
|
||||
// disables key-frame insertion.
|
||||
int kmin;
|
||||
int kmax; // Minimum and maximum distance between consecutive key
|
||||
// frames in the output. The library may insert some key
|
||||
// frames as needed to satisfy this criteria.
|
||||
// Note that these conditions should hold: kmax > kmin
|
||||
// and kmin >= kmax / 2 + 1. Also, if kmax <= 0, then
|
||||
// key-frame insertion is disabled; and if kmax == 1,
|
||||
// then all frames will be key-frames (kmin value does
|
||||
// not matter for these special cases).
|
||||
int allow_mixed; // If true, use mixed compression mode; may choose
|
||||
// either lossy and lossless for each frame.
|
||||
int verbose; // If true, print info and warning messages to stderr.
|
||||
|
||||
uint32_t padding[4]; // Padding for later use.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN int WebPAnimEncoderOptionsInitInternal(
|
||||
WebPAnimEncoderOptions*, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPAnimEncoderOptions
|
||||
// structure before modification. Returns false in case of version mismatch.
|
||||
// WebPAnimEncoderOptionsInit() must have succeeded before using the
|
||||
// 'enc_options' object.
|
||||
static WEBP_INLINE int WebPAnimEncoderOptionsInit(
|
||||
WebPAnimEncoderOptions* enc_options) {
|
||||
return WebPAnimEncoderOptionsInitInternal(enc_options, WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN WebPAnimEncoder* WebPAnimEncoderNewInternal(
|
||||
int, int, const WebPAnimEncoderOptions*, int);
|
||||
|
||||
// Creates and initializes a WebPAnimEncoder object.
|
||||
// Parameters:
|
||||
// width/height - (in) canvas width and height of the animation.
|
||||
// enc_options - (in) encoding options; can be passed NULL to pick
|
||||
// reasonable defaults.
|
||||
// Returns:
|
||||
// A pointer to the newly created WebPAnimEncoder object.
|
||||
// Or NULL in case of memory error.
|
||||
static WEBP_INLINE WebPAnimEncoder* WebPAnimEncoderNew(
|
||||
int width, int height, const WebPAnimEncoderOptions* enc_options) {
|
||||
return WebPAnimEncoderNewInternal(width, height, enc_options,
|
||||
WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Optimize the given frame for WebP, encode it and add it to the
|
||||
// WebPAnimEncoder object.
|
||||
// The last call to 'WebPAnimEncoderAdd' should be with frame = NULL, which
|
||||
// indicates that no more frames are to be added. This call is also used to
|
||||
// determine the duration of the last frame.
|
||||
// Parameters:
|
||||
// enc - (in/out) object to which the frame is to be added.
|
||||
// frame - (in/out) frame data in ARGB or YUV(A) format. If it is in YUV(A)
|
||||
// format, it will be converted to ARGB, which incurs a small loss.
|
||||
// timestamp_ms - (in) timestamp of this frame in milliseconds.
|
||||
// Duration of a frame would be calculated as
|
||||
// "timestamp of next frame - timestamp of this frame".
|
||||
// Hence, timestamps should be in non-decreasing order.
|
||||
// config - (in) encoding options; can be passed NULL to pick
|
||||
// reasonable defaults.
|
||||
// Returns:
|
||||
// On error, returns false and frame->error_code is set appropriately.
|
||||
// Otherwise, returns true.
|
||||
WEBP_EXTERN int WebPAnimEncoderAdd(
|
||||
WebPAnimEncoder* enc, struct WebPPicture* frame, int timestamp_ms,
|
||||
const struct WebPConfig* config);
|
||||
|
||||
// Assemble all frames added so far into a WebP bitstream.
|
||||
// This call should be preceded by a call to 'WebPAnimEncoderAdd' with
|
||||
// frame = NULL; if not, the duration of the last frame will be internally
|
||||
// estimated.
|
||||
// Parameters:
|
||||
// enc - (in/out) object from which the frames are to be assembled.
|
||||
// webp_data - (out) generated WebP bitstream.
|
||||
// Returns:
|
||||
// True on success.
|
||||
WEBP_EXTERN int WebPAnimEncoderAssemble(WebPAnimEncoder* enc,
|
||||
WebPData* webp_data);
|
||||
|
||||
// Get error string corresponding to the most recent call using 'enc'. The
|
||||
// returned string is owned by 'enc' and is valid only until the next call to
|
||||
// WebPAnimEncoderAdd() or WebPAnimEncoderAssemble() or WebPAnimEncoderDelete().
|
||||
// Parameters:
|
||||
// enc - (in/out) object from which the error string is to be fetched.
|
||||
// Returns:
|
||||
// NULL if 'enc' is NULL. Otherwise, returns the error string if the last call
|
||||
// to 'enc' had an error, or an empty string if the last call was a success.
|
||||
WEBP_EXTERN const char* WebPAnimEncoderGetError(WebPAnimEncoder* enc);
|
||||
|
||||
// Deletes the WebPAnimEncoder object.
|
||||
// Parameters:
|
||||
// enc - (in/out) object to be deleted
|
||||
WEBP_EXTERN void WebPAnimEncoderDelete(WebPAnimEncoder* enc);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_MUX_H_
|
||||
@@ -0,0 +1,98 @@
|
||||
// Copyright 2012 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Data-types common to the mux and demux libraries.
|
||||
//
|
||||
// Author: Urvang (urvang@google.com)
|
||||
|
||||
#ifndef WEBP_WEBP_MUX_TYPES_H_
|
||||
#define WEBP_WEBP_MUX_TYPES_H_
|
||||
|
||||
#include <string.h> // memset()
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPFeatureFlags WebPFeatureFlags;
|
||||
// typedef enum WebPMuxAnimDispose WebPMuxAnimDispose;
|
||||
// typedef enum WebPMuxAnimBlend WebPMuxAnimBlend;
|
||||
typedef struct WebPData WebPData;
|
||||
|
||||
// VP8X Feature Flags.
|
||||
typedef enum WebPFeatureFlags {
|
||||
ANIMATION_FLAG = 0x00000002,
|
||||
XMP_FLAG = 0x00000004,
|
||||
EXIF_FLAG = 0x00000008,
|
||||
ALPHA_FLAG = 0x00000010,
|
||||
ICCP_FLAG = 0x00000020,
|
||||
|
||||
ALL_VALID_FLAGS = 0x0000003e
|
||||
} WebPFeatureFlags;
|
||||
|
||||
// Dispose method (animation only). Indicates how the area used by the current
|
||||
// frame is to be treated before rendering the next frame on the canvas.
|
||||
typedef enum WebPMuxAnimDispose {
|
||||
WEBP_MUX_DISPOSE_NONE, // Do not dispose.
|
||||
WEBP_MUX_DISPOSE_BACKGROUND // Dispose to background color.
|
||||
} WebPMuxAnimDispose;
|
||||
|
||||
// Blend operation (animation only). Indicates how transparent pixels of the
|
||||
// current frame are blended with those of the previous canvas.
|
||||
typedef enum WebPMuxAnimBlend {
|
||||
WEBP_MUX_BLEND, // Blend.
|
||||
WEBP_MUX_NO_BLEND // Do not blend.
|
||||
} WebPMuxAnimBlend;
|
||||
|
||||
// Data type used to describe 'raw' data, e.g., chunk data
|
||||
// (ICC profile, metadata) and WebP compressed image data.
|
||||
// 'bytes' memory must be allocated using WebPMalloc() and such.
|
||||
struct WebPData {
|
||||
const uint8_t* bytes;
|
||||
size_t size;
|
||||
};
|
||||
|
||||
// Initializes the contents of the 'webp_data' object with default values.
|
||||
static WEBP_INLINE void WebPDataInit(WebPData* webp_data) {
|
||||
if (webp_data != NULL) {
|
||||
memset(webp_data, 0, sizeof(*webp_data));
|
||||
}
|
||||
}
|
||||
|
||||
// Clears the contents of the 'webp_data' object by calling WebPFree().
|
||||
// Does not deallocate the object itself.
|
||||
static WEBP_INLINE void WebPDataClear(WebPData* webp_data) {
|
||||
if (webp_data != NULL) {
|
||||
WebPFree((void*)webp_data->bytes);
|
||||
WebPDataInit(webp_data);
|
||||
}
|
||||
}
|
||||
|
||||
// Allocates necessary storage for 'dst' and copies the contents of 'src'.
|
||||
// Returns true on success.
|
||||
static WEBP_INLINE int WebPDataCopy(const WebPData* src, WebPData* dst) {
|
||||
if (src == NULL || dst == NULL) return 0;
|
||||
WebPDataInit(dst);
|
||||
if (src->bytes != NULL && src->size != 0) {
|
||||
dst->bytes = (uint8_t*)WebPMalloc(src->size);
|
||||
if (dst->bytes == NULL) return 0;
|
||||
memcpy((void*)dst->bytes, src->bytes, src->size);
|
||||
dst->size = src->size;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_MUX_TYPES_H_
|
||||
@@ -0,0 +1,68 @@
|
||||
// Copyright 2010 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Common types + memory wrappers
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_TYPES_H_
|
||||
#define WEBP_WEBP_TYPES_H_
|
||||
|
||||
#include <stddef.h> // for size_t
|
||||
|
||||
#ifndef _MSC_VER
|
||||
#include <inttypes.h>
|
||||
#if defined(__cplusplus) || !defined(__STRICT_ANSI__) || \
|
||||
(defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L)
|
||||
#define WEBP_INLINE inline
|
||||
#else
|
||||
#define WEBP_INLINE
|
||||
#endif
|
||||
#else
|
||||
typedef signed char int8_t;
|
||||
typedef unsigned char uint8_t;
|
||||
typedef signed short int16_t;
|
||||
typedef unsigned short uint16_t;
|
||||
typedef signed int int32_t;
|
||||
typedef unsigned int uint32_t;
|
||||
typedef unsigned long long int uint64_t;
|
||||
typedef long long int int64_t;
|
||||
#define WEBP_INLINE __forceinline
|
||||
#endif /* _MSC_VER */
|
||||
|
||||
#ifndef WEBP_EXTERN
|
||||
// This explicitly marks library functions and allows for changing the
|
||||
// signature for e.g., Windows DLL builds.
|
||||
# if defined(__GNUC__) && __GNUC__ >= 4
|
||||
# define WEBP_EXTERN extern __attribute__ ((visibility ("default")))
|
||||
# else
|
||||
# define WEBP_EXTERN extern
|
||||
# endif /* __GNUC__ >= 4 */
|
||||
#endif /* WEBP_EXTERN */
|
||||
|
||||
// Macro to check ABI compatibility (same major revision number)
|
||||
#define WEBP_ABI_IS_INCOMPATIBLE(a, b) (((a) >> 8) != ((b) >> 8))
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
// Allocates 'size' bytes of memory. Returns NULL upon error. Memory
|
||||
// must be deallocated by calling WebPFree(). This function is made available
|
||||
// by the core 'libwebp' library.
|
||||
WEBP_EXTERN void* WebPMalloc(size_t size);
|
||||
|
||||
// Releases memory returned by the WebPDecode*() functions (from decode.h).
|
||||
WEBP_EXTERN void WebPFree(void* ptr);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_TYPES_H_
|
||||
Binary file not shown.
Binary file not shown.
Binary file not shown.
@@ -0,0 +1,29 @@
|
||||
# How to Contribute
|
||||
|
||||
We'd love to accept your patches and contributions to this project. There are
|
||||
just a few small guidelines you need to follow.
|
||||
|
||||
## Contributor License Agreement
|
||||
|
||||
Contributions to this project must be accompanied by a Contributor License
|
||||
Agreement. You (or your employer) retain the copyright to your contribution;
|
||||
this simply gives us permission to use and redistribute your contributions as
|
||||
part of the project. Head over to <https://cla.developers.google.com/> to see
|
||||
your current agreements on file or to sign a new one.
|
||||
|
||||
You generally only need to submit a CLA once, so if you've already submitted one
|
||||
(even if it was for a different project), you probably don't need to do it
|
||||
again.
|
||||
|
||||
## Code reviews
|
||||
|
||||
All submissions, including submissions by project members, require review. We
|
||||
use a [Gerrit](https://www.gerritcodereview.com) instance hosted at
|
||||
https://chromium-review.googlesource.com for this purpose. See the
|
||||
[WebM Project page](https://www.webmproject.org/code/contribute/submitting-patches/)
|
||||
for additional details.
|
||||
|
||||
## Community Guidelines
|
||||
|
||||
This project follows
|
||||
[Google's Open Source Community Guidelines](https://opensource.google.com/conduct/).
|
||||
@@ -0,0 +1,65 @@
|
||||
# WebP Codec
|
||||
|
||||
```
|
||||
__ __ ____ ____ ____
|
||||
/ \\/ \/ _ \/ _ )/ _ \
|
||||
\ / __/ _ \ __/
|
||||
\__\__/\____/\_____/__/ ____ ___
|
||||
/ _/ / \ \ / _ \/ _/
|
||||
/ \_/ / / \ \ __/ \__
|
||||
\____/____/\_____/_____/____/v1.2.4
|
||||
```
|
||||
|
||||
WebP codec is a library to encode and decode images in WebP format. This package
|
||||
contains the library that can be used in other programs to add WebP support, as
|
||||
well as the command line tools 'cwebp' and 'dwebp' to compress and decompress
|
||||
images respectively.
|
||||
|
||||
See https://developers.google.com/speed/webp for details on the image format.
|
||||
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp
|
||||
|
||||
It is released under the same license as the WebM project. See
|
||||
https://www.webmproject.org/license/software/ or the "COPYING" file for details.
|
||||
An additional intellectual property rights grant can be found in the file
|
||||
PATENTS.
|
||||
|
||||
## Files
|
||||
|
||||
* bin/cwebp : encoding tool
|
||||
* bin/dwebp : decoding tool
|
||||
* bin/gif2webp : gif conversion tool
|
||||
* bin/img2webp : animation creation tool
|
||||
* bin/vwebp : webp visualization tool
|
||||
* bin/webpinfo : webp analysis tool
|
||||
* bin/webpmux : webp muxing tool
|
||||
* bin/anim\_diff : webp file comparison tool
|
||||
* bin/anim\_dump : tool for dumping animation frames
|
||||
* bin/get\_disto : tool for calculating file distortion
|
||||
* bin/webp\_quality : webp quality estimation tool
|
||||
* doc/ : manual in HTML and text formats
|
||||
* lib/ : static libraries
|
||||
* include/webp : headers
|
||||
|
||||
## Encoding and Decoding Tools
|
||||
|
||||
The bin/ directory contains tools to encode and decode images and animations,
|
||||
view information about WebP images, and more. See the
|
||||
[tools documentation](doc/tools.md).
|
||||
|
||||
## APIs
|
||||
|
||||
See the [APIs documentation](doc/api.md).
|
||||
|
||||
## Bugs
|
||||
|
||||
Please report all bugs to the issue tracker: https://bugs.chromium.org/p/webp
|
||||
|
||||
Patches welcome! See [how to contribute](CONTRIBUTING.md).
|
||||
|
||||
## Discuss
|
||||
|
||||
Email: webp-discuss@webmproject.org
|
||||
|
||||
Web: https://groups.google.com/a/webmproject.org/group/webp-discuss
|
||||
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@@ -0,0 +1,385 @@
|
||||
# WebP APIs
|
||||
|
||||
## Encoding API
|
||||
|
||||
The main encoding functions are available in the header src/webp/encode.h
|
||||
|
||||
The ready-to-use ones are:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
```
|
||||
|
||||
They will convert raw RGB samples to a WebP data. The only control supplied is
|
||||
the quality factor.
|
||||
|
||||
There are some variants for using the lossless format:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
```
|
||||
|
||||
Of course in this case, no quality factor is needed since the compression occurs
|
||||
without loss of the input values, at the expense of larger output sizes.
|
||||
|
||||
### Advanced encoding API
|
||||
|
||||
A more advanced API is based on the WebPConfig and WebPPicture structures.
|
||||
|
||||
WebPConfig contains the encoding settings and is not tied to a particular
|
||||
picture. WebPPicture contains input data, on which some WebPConfig will be used
|
||||
for compression. The encoding flow looks like:
|
||||
|
||||
```c
|
||||
#include <webp/encode.h>
|
||||
|
||||
// Setup a config, starting form a preset and tuning some additional
|
||||
// parameters
|
||||
WebPConfig config;
|
||||
if (!WebPConfigPreset(&config, WEBP_PRESET_PHOTO, quality_factor)) {
|
||||
return 0; // version error
|
||||
}
|
||||
// ... additional tuning
|
||||
config.sns_strength = 90;
|
||||
config.filter_sharpness = 6;
|
||||
config_error = WebPValidateConfig(&config); // not mandatory, but useful
|
||||
|
||||
// Setup the input data
|
||||
WebPPicture pic;
|
||||
if (!WebPPictureInit(&pic)) {
|
||||
return 0; // version error
|
||||
}
|
||||
pic.width = width;
|
||||
pic.height = height;
|
||||
// allocated picture of dimension width x height
|
||||
if (!WebPPictureAlloc(&pic)) {
|
||||
return 0; // memory error
|
||||
}
|
||||
// at this point, 'pic' has been initialized as a container,
|
||||
// and can receive the Y/U/V samples.
|
||||
// Alternatively, one could use ready-made import functions like
|
||||
// WebPPictureImportRGB(), which will take care of memory allocation.
|
||||
// In any case, past this point, one will have to call
|
||||
// WebPPictureFree(&pic) to reclaim memory.
|
||||
|
||||
// Set up a byte-output write method. WebPMemoryWriter, for instance.
|
||||
WebPMemoryWriter wrt;
|
||||
WebPMemoryWriterInit(&wrt); // initialize 'wrt'
|
||||
|
||||
pic.writer = MyFileWriter;
|
||||
pic.custom_ptr = my_opaque_structure_to_make_MyFileWriter_work;
|
||||
|
||||
// Compress!
|
||||
int ok = WebPEncode(&config, &pic); // ok = 0 => error occurred!
|
||||
WebPPictureFree(&pic); // must be called independently of the 'ok' result.
|
||||
|
||||
// output data should have been handled by the writer at that point.
|
||||
// -> compressed data is the memory buffer described by wrt.mem / wrt.size
|
||||
|
||||
// deallocate the memory used by compressed data
|
||||
WebPMemoryWriterClear(&wrt);
|
||||
```
|
||||
|
||||
## Decoding API
|
||||
|
||||
This is mainly just one function to call:
|
||||
|
||||
```c
|
||||
#include "webp/decode.h"
|
||||
uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
Please have a look at the file src/webp/decode.h for the details. There are
|
||||
variants for decoding in BGR/RGBA/ARGB/BGRA order, along with decoding to raw
|
||||
Y'CbCr samples. One can also decode the image directly into a pre-allocated
|
||||
buffer.
|
||||
|
||||
To detect a WebP file and gather the picture's dimensions, the function:
|
||||
|
||||
```c
|
||||
int WebPGetInfo(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
is supplied. No decoding is involved when using it.
|
||||
|
||||
### Incremental decoding API
|
||||
|
||||
In the case when data is being progressively transmitted, pictures can still be
|
||||
incrementally decoded using a slightly more complicated API. Decoder state is
|
||||
stored into an instance of the WebPIDecoder object. This object can be created
|
||||
with the purpose of decoding either RGB or Y'CbCr samples. For instance:
|
||||
|
||||
```c
|
||||
WebPDecBuffer buffer;
|
||||
WebPInitDecBuffer(&buffer);
|
||||
buffer.colorspace = MODE_BGR;
|
||||
...
|
||||
WebPIDecoder* idec = WebPINewDecoder(&buffer);
|
||||
```
|
||||
|
||||
As data is made progressively available, this incremental-decoder object can be
|
||||
used to decode the picture further. There are two (mutually exclusive) ways to
|
||||
pass freshly arrived data:
|
||||
|
||||
either by appending the fresh bytes:
|
||||
|
||||
```c
|
||||
WebPIAppend(idec, fresh_data, size_of_fresh_data);
|
||||
```
|
||||
|
||||
or by just mentioning the new size of the transmitted data:
|
||||
|
||||
```c
|
||||
WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
|
||||
```
|
||||
|
||||
Note that 'buffer' can be modified between each call to WebPIUpdate, in
|
||||
particular when the buffer is resized to accommodate larger data.
|
||||
|
||||
These functions will return the decoding status: either VP8_STATUS_SUSPENDED if
|
||||
decoding is not finished yet or VP8_STATUS_OK when decoding is done. Any other
|
||||
status is an error condition.
|
||||
|
||||
The 'idec' object must always be released (even upon an error condition) by
|
||||
calling: WebPDelete(idec).
|
||||
|
||||
To retrieve partially decoded picture samples, one must use the corresponding
|
||||
method: WebPIDecGetRGB or WebPIDecGetYUVA. It will return the last displayable
|
||||
pixel row.
|
||||
|
||||
Lastly, note that decoding can also be performed into a pre-allocated pixel
|
||||
buffer. This buffer must be passed when creating a WebPIDecoder, calling
|
||||
WebPINewRGB() or WebPINewYUVA().
|
||||
|
||||
Please have a look at the src/webp/decode.h header for further details.
|
||||
|
||||
### Advanced Decoding API
|
||||
|
||||
WebP decoding supports an advanced API which provides on-the-fly cropping and
|
||||
rescaling, something of great usefulness on memory-constrained environments like
|
||||
mobile phones. Basically, the memory usage will scale with the output's size,
|
||||
not the input's, when one only needs a quick preview or a zoomed in portion of
|
||||
an otherwise too-large picture. Some CPU can be saved too, incidentally.
|
||||
|
||||
```c
|
||||
// A) Init a configuration object
|
||||
WebPDecoderConfig config;
|
||||
CHECK(WebPInitDecoderConfig(&config));
|
||||
|
||||
// B) optional: retrieve the bitstream's features.
|
||||
CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
|
||||
|
||||
// C) Adjust 'config' options, if needed
|
||||
config.options.no_fancy_upsampling = 1;
|
||||
config.options.use_scaling = 1;
|
||||
config.options.scaled_width = scaledWidth();
|
||||
config.options.scaled_height = scaledHeight();
|
||||
// etc.
|
||||
|
||||
// D) Specify 'config' output options for specifying output colorspace.
|
||||
// Optionally the external image decode buffer can also be specified.
|
||||
config.output.colorspace = MODE_BGRA;
|
||||
// Optionally, the config.output can be pointed to an external buffer as
|
||||
// well for decoding the image. This externally supplied memory buffer
|
||||
// should be big enough to store the decoded picture.
|
||||
config.output.u.RGBA.rgba = (uint8_t*) memory_buffer;
|
||||
config.output.u.RGBA.stride = scanline_stride;
|
||||
config.output.u.RGBA.size = total_size_of_the_memory_buffer;
|
||||
config.output.is_external_memory = 1;
|
||||
|
||||
// E) Decode the WebP image. There are two variants w.r.t decoding image.
|
||||
// The first one (E.1) decodes the full image and the second one (E.2) is
|
||||
// used to incrementally decode the image using small input buffers.
|
||||
// Any one of these steps can be used to decode the WebP image.
|
||||
|
||||
// E.1) Decode full image.
|
||||
CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
|
||||
|
||||
// E.2) Decode image incrementally.
|
||||
WebPIDecoder* const idec = WebPIDecode(NULL, NULL, &config);
|
||||
CHECK(idec != NULL);
|
||||
while (bytes_remaining > 0) {
|
||||
VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
|
||||
if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
|
||||
bytes_remaining -= bytes_read;
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
WebPIDelete(idec);
|
||||
|
||||
// F) Decoded image is now in config.output (and config.output.u.RGBA).
|
||||
// It can be saved, displayed or otherwise processed.
|
||||
|
||||
// G) Reclaim memory allocated in config's object. It's safe to call
|
||||
// this function even if the memory is external and wasn't allocated
|
||||
// by WebPDecode().
|
||||
WebPFreeDecBuffer(&config.output);
|
||||
```
|
||||
|
||||
## Webp Mux
|
||||
|
||||
WebPMux is a set of two libraries 'Mux' and 'Demux' for creation, extraction and
|
||||
manipulation of an extended format WebP file, which can have features like color
|
||||
profile, metadata and animation. Reference command-line tools `webpmux` and
|
||||
`vwebp` as well as the WebP container specification
|
||||
'doc/webp-container-spec.txt' are also provided in this package, see the
|
||||
[tools documentation](tools.md).
|
||||
|
||||
### Mux API
|
||||
|
||||
The Mux API contains methods for adding data to and reading data from WebP
|
||||
files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
|
||||
Other features may be added in subsequent releases.
|
||||
|
||||
Example#1 (pseudo code): Creating a WebPMux object with image data, color
|
||||
profile and XMP metadata.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
WebPMux* mux = WebPMuxNew();
|
||||
// ... (Prepare image data).
|
||||
WebPMuxSetImage(mux, &image, copy_data);
|
||||
// ... (Prepare ICC profile data).
|
||||
WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
|
||||
// ... (Prepare XMP metadata).
|
||||
WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
|
||||
// Get data from mux in WebP RIFF format.
|
||||
WebPMuxAssemble(mux, &output_data);
|
||||
WebPMuxDelete(mux);
|
||||
// ... (Consume output_data; e.g. write output_data.bytes to file).
|
||||
WebPDataClear(&output_data);
|
||||
```
|
||||
|
||||
Example#2 (pseudo code): Get image and color profile data from a WebP file.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
// ... (Read data from file).
|
||||
WebPMux* mux = WebPMuxCreate(&data, copy_data);
|
||||
WebPMuxGetFrame(mux, 1, &image);
|
||||
// ... (Consume image; e.g. call WebPDecode() to decode the data).
|
||||
WebPMuxGetChunk(mux, "ICCP", &icc_profile);
|
||||
// ... (Consume icc_profile).
|
||||
WebPMuxDelete(mux);
|
||||
free(data);
|
||||
```
|
||||
|
||||
For a detailed Mux API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
### Demux API
|
||||
|
||||
The Demux API enables extraction of images and extended format data from WebP
|
||||
files. This API currently supports reading of XMP/EXIF metadata, ICC profile and
|
||||
animated images. Other features may be added in subsequent releases.
|
||||
|
||||
Code example: Demuxing WebP data to extract all the frames, ICC profile and
|
||||
EXIF/XMP metadata.
|
||||
|
||||
```c
|
||||
WebPDemuxer* demux = WebPDemux(&webp_data);
|
||||
uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
|
||||
uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
|
||||
// ... (Get information about the features present in the WebP file).
|
||||
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
|
||||
|
||||
// ... (Iterate over all frames).
|
||||
WebPIterator iter;
|
||||
if (WebPDemuxGetFrame(demux, 1, &iter)) {
|
||||
do {
|
||||
// ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
|
||||
// ... and get other frame properties like width, height, offsets etc.
|
||||
// ... see 'struct WebPIterator' below for more info).
|
||||
} while (WebPDemuxNextFrame(&iter));
|
||||
WebPDemuxReleaseIterator(&iter);
|
||||
}
|
||||
|
||||
// ... (Extract metadata).
|
||||
WebPChunkIterator chunk_iter;
|
||||
if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
|
||||
// ... (Consume the ICC profile in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
|
||||
// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
|
||||
// ... (Consume the XMP metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
WebPDemuxDelete(demux);
|
||||
```
|
||||
|
||||
For a detailed Demux API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
|
||||
## AnimEncoder API
|
||||
|
||||
The AnimEncoder API can be used to create animated WebP images.
|
||||
|
||||
Code example:
|
||||
|
||||
```c
|
||||
WebPAnimEncoderOptions enc_options;
|
||||
WebPAnimEncoderOptionsInit(&enc_options);
|
||||
// ... (Tune 'enc_options' as needed).
|
||||
WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
|
||||
while(<there are more frames>) {
|
||||
WebPConfig config;
|
||||
WebPConfigInit(&config);
|
||||
// ... (Tune 'config' as needed).
|
||||
WebPAnimEncoderAdd(enc, frame, duration, &config);
|
||||
}
|
||||
WebPAnimEncoderAssemble(enc, webp_data);
|
||||
WebPAnimEncoderDelete(enc);
|
||||
// ... (Write the 'webp_data' to a file, or re-mux it further).
|
||||
```
|
||||
|
||||
For a detailed AnimEncoder API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
## AnimDecoder API
|
||||
|
||||
This AnimDecoder API allows decoding (possibly) animated WebP images.
|
||||
|
||||
Code Example:
|
||||
|
||||
```c
|
||||
WebPAnimDecoderOptions dec_options;
|
||||
WebPAnimDecoderOptionsInit(&dec_options);
|
||||
// Tune 'dec_options' as needed.
|
||||
WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
|
||||
WebPAnimInfo anim_info;
|
||||
WebPAnimDecoderGetInfo(dec, &anim_info);
|
||||
for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
|
||||
while (WebPAnimDecoderHasMoreFrames(dec)) {
|
||||
uint8_t* buf;
|
||||
int timestamp;
|
||||
WebPAnimDecoderGetNext(dec, &buf, ×tamp);
|
||||
// ... (Render 'buf' based on 'timestamp').
|
||||
// ... (Do NOT free 'buf', as it is owned by 'dec').
|
||||
}
|
||||
WebPAnimDecoderReset(dec);
|
||||
}
|
||||
const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
|
||||
// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
|
||||
WebPAnimDecoderDelete(dec);
|
||||
```
|
||||
|
||||
For a detailed AnimDecoder API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
@@ -0,0 +1,663 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:54 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>CWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>CWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp −
|
||||
compress an image file to a WebP file</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
[<i>options</i>] <i>input_file −o
|
||||
output_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>cwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
compresses an image using the WebP format. Input format can
|
||||
be either PNG, JPEG, TIFF, WebP or raw Y’CbCr samples.
|
||||
Note: Animated PNG and WebP files are not supported.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
−o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>cwebp</b> will perform compression
|
||||
but only report statistics. Using "−" as
|
||||
output name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with a
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be
|
||||
ignored.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−H,
|
||||
−longhelp</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A summary of all the possible
|
||||
options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−lossless</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode the image without any
|
||||
loss. For images with fully transparent area, the invisible
|
||||
pixel values (R/G/B or Y/U/V) will be preserved only if the
|
||||
−exact option is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−near_lossless</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the level of
|
||||
near−lossless image preprocessing. This option adjusts
|
||||
pixel values to help compressibility, but has minimal impact
|
||||
on the visual quality. It triggers lossless compression mode
|
||||
automatically. The range is 0 (maximum preprocessing) to 100
|
||||
(no preprocessing, the default). The typical value is around
|
||||
60. Note that lossy with <b>−q 100</b> can at times
|
||||
yield better results.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−q</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossy compression (default), a small factor
|
||||
produces a smaller file with lower quality. Best quality is
|
||||
achieved by using a value of 100. <br>
|
||||
In case of lossless compression (specified by the
|
||||
<b>−lossless</b> option), a small factor enables
|
||||
faster compression speed, but produces a larger file.
|
||||
Maximum compression is achieved by using a value of 100.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−z</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Switch on
|
||||
<b>lossless</b> compression mode with the specified level
|
||||
between 0 and 9, with level 0 being the fastest, 9 being the
|
||||
slowest. Fast mode produces larger file size than slower
|
||||
ones. A good default is <b>−z 6</b>. This option is
|
||||
actually a shortcut for some predefined settings for quality
|
||||
and method. If options <b>−q</b> or <b>−m</b>
|
||||
are subsequently used, they will invalidate the effect of
|
||||
this option.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_q</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for alpha compression between 0 and 100. Lossless
|
||||
compression of alpha is achieved using a value of 100, while
|
||||
the lower values result in a lossy compression. The default
|
||||
is 100.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−preset</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a set of
|
||||
pre−defined parameters to suit a particular type of
|
||||
source material. Possible values are: <b>default</b>,
|
||||
<b>photo</b>, <b>picture</b>, <b>drawing</b>, <b>icon</b>,
|
||||
<b>text</b>. Since <b>−preset</b> overwrites the other
|
||||
parameters’ values (except the <b>−q</b> one),
|
||||
this option should preferably appear first in the order of
|
||||
the arguments.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−m</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
compression method to use. This parameter controls the trade
|
||||
off between encoding speed and the compressed file size and
|
||||
quality. Possible values range from 0 to 6. Default value is
|
||||
4. When higher values are used, the encoder will spend more
|
||||
time inspecting additional encoding possibilities and decide
|
||||
on the quality gain. Lower value can result in faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−crop</b>
|
||||
<i>x_position y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the source to a rectangle
|
||||
with top−left corner at coordinates
|
||||
(<b>x_position</b>, <b>y_position</b>) and size <b>width</b>
|
||||
x <b>height</b>. This cropping area must be fully contained
|
||||
within the source rectangle. Note: the cropping is applied
|
||||
<i>before</i> any scaling.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−resize</b> <i>width
|
||||
height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Resize the source to a
|
||||
rectangle with size <b>width</b> x <b>height</b>. If either
|
||||
(but not both) of the <b>width</b> or <b>height</b>
|
||||
parameters is 0, the value will be calculated preserving the
|
||||
aspect−ratio. Note: scaling is applied <i>after</i>
|
||||
cropping.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use
|
||||
multi−threading for encoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−low_memory</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Reduce memory usage of lossy
|
||||
encoding by saving four times the compressed size
|
||||
(typically). This will make the encoding slower and the
|
||||
output slightly different in size and distortion. This flag
|
||||
is only effective for methods 3 and up, and is off by
|
||||
default. Note that leaving this flag off will have some side
|
||||
effects on the bitstream: it forces certain bitstream
|
||||
features like number of partitions (forced to 1). Note that
|
||||
a more detailed report of bitstream size is printed by
|
||||
<b>cwebp</b> when using this option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOSSY
|
||||
OPTIONS</b> <br>
|
||||
These options are only effective when doing lossy encoding
|
||||
(the default, with or without alpha). <b><br>
|
||||
−size</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target size (in
|
||||
bytes) to try and reach for the compressed output. The
|
||||
compressor will make several passes of partial encoding in
|
||||
order to get as close as possible to this target. If both
|
||||
<b>−size</b> and <b>−psnr</b> are used,
|
||||
<b>−size</b> value will prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−psnr</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target PSNR (in dB)
|
||||
to try and reach for the compressed output. The compressor
|
||||
will make several passes of partial encoding in order to get
|
||||
as close as possible to this target. If both
|
||||
<b>−size</b> and <b>−psnr</b> are used,
|
||||
<b>−size</b> value will prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−pass</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set a maximum number of passes
|
||||
to use during the dichotomy used by options
|
||||
<b>−size</b> or <b>−psnr</b>. Maximum value is
|
||||
10, default is 1. If options <b>−size</b> or
|
||||
<b>−psnr</b> were used, but <b>−pass</b>
|
||||
wasn’t specified, a default value of ’6’
|
||||
passes will be used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−qrange</b> <i>int
|
||||
int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specifies the permissible
|
||||
interval for the quality factor. This is particularly useful
|
||||
when using multi-pass (<b>−size</b> or
|
||||
<b>−psnr</b> options). Default is 0 100. If the
|
||||
quality factor is outside this range, it will be clamped. If
|
||||
the minimum value must be less or equal to the maximum
|
||||
one.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−af</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Turns
|
||||
auto−filter on. This algorithm will spend additional
|
||||
time optimizing the filtering strength to reach a
|
||||
well−balanced quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−jpeg_like</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the internal parameter
|
||||
mapping to better match the expected size of JPEG
|
||||
compression. This flag will generally produce an output file
|
||||
of similar size to its JPEG equivalent (for the same
|
||||
<b>−q</b> setting), but with less visual
|
||||
distortion.</p>
|
||||
|
||||
<p style="margin-left:11%;">Advanced options:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−f</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
strength of the deblocking filter, between 0 (no filtering)
|
||||
and 100 (maximum filtering). A value of 0 will turn off any
|
||||
filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear.
|
||||
Typical values are usually in the range of 20 to 50.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sharpness</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the sharpness of the
|
||||
filtering (if used). Range is 0 (sharpest) to 7 (least
|
||||
sharp). Default is 0.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−strong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use strong filtering (if
|
||||
filtering is being used thanks to the <b>−f</b>
|
||||
option). Strong filtering is on by default.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nostrong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable strong filtering (if
|
||||
filtering is being used thanks to the <b>−f</b>
|
||||
option) and use simple filtering instead.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sharp_yuv</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use more accurate and sharper
|
||||
RGB->YUV conversion if needed. Note that this process is
|
||||
slower than the default ’fast’ RGB->YUV
|
||||
conversion.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sns</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the amplitude of the
|
||||
spatial noise shaping. Spatial noise shaping (or <b>sns</b>
|
||||
for short) refers to a general collection of built−in
|
||||
algorithms used to decide which area of the picture should
|
||||
use relatively less bits, and where else to better transfer
|
||||
these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is
|
||||
50.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−segments</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the number of partitions
|
||||
to use during the segmentation of the sns algorithm.
|
||||
Segments should be in range 1 to 4. Default value is 4. This
|
||||
option has no effect for methods 3 and up, unless
|
||||
<b>−low_memory</b> is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−partition_limit</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Degrade quality by limiting the
|
||||
number of bits used by some macroblocks. Range is 0 (no
|
||||
degradation, the default) to 100 (full degradation). Useful
|
||||
values are usually around 30−70 for moderately large
|
||||
images. In the VP8 format, the so−called control
|
||||
partition has a limit of 512k and is used to store the
|
||||
following information: whether the macroblock is skipped,
|
||||
which segment it belongs to, whether it is coded as intra
|
||||
4x4 or intra 16x16 mode, and finally the prediction modes to
|
||||
use for each of the sub−blocks. For a very large
|
||||
image, 512k only leaves room to few bits per 16x16
|
||||
macroblock. The absolute minimum is 4 bits per macroblock.
|
||||
Skip, segment, and mode information can use up almost all
|
||||
these 4 bits (although the case is unlikely), which is
|
||||
problematic for very large images. The partition_limit
|
||||
factor controls how frequently the most bit−costly
|
||||
mode (intra 4x4) will be used. This is useful in case the
|
||||
512k limit is reached and the following message is
|
||||
displayed: <i>Error code: 6 (PARTITION0_OVERFLOW: Partition
|
||||
#0 is too big to fit 512k)</i>. If using
|
||||
<b>−partition_limit</b> is not enough to meet the 512k
|
||||
constraint, one should use less segments in order to save
|
||||
more header bits per macroblock. See the
|
||||
<b>−segments</b> option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOGGING
|
||||
OPTIONS</b> <br>
|
||||
These options control the level of output:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information (encoding time in particular).</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_psnr</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average PSNR
|
||||
(Peak−Signal−To−Noise ratio).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_ssim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average SSIM
|
||||
(structural similarity metric, see
|
||||
https://en.wikipedia.org/wiki/SSIM for additional
|
||||
details).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_lsim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report local
|
||||
similarity metric (sum of lowest error amongst the
|
||||
collocated pixel neighbors).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−progress</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Report encoding progress in
|
||||
percent.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−short</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Only print brief
|
||||
information (output file size and PSNR) for testing
|
||||
purposes.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−map</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Output additional
|
||||
ASCII−map of encoding information. Possible map values
|
||||
range from 1 to 6. This is only meant to help debugging.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>ADDITIONAL
|
||||
OPTIONS</b> <br>
|
||||
More advanced options are: <b><br>
|
||||
−s</b> <i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify that the input file
|
||||
actually consists of raw Y’CbCr samples following the
|
||||
ITU−R BT.601 recommendation, in 4:2:0 linear format.
|
||||
The luma plane has size <b>width</b> x <b>height</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−pre</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify some preprocessing
|
||||
steps. Using a value of ’2’ will trigger
|
||||
quality−dependent pseudo−random dithering during
|
||||
RGBA−>YUVA conversion (lossy compression only).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_filter</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the predictive
|
||||
filtering method for the alpha plane. One of
|
||||
’none’, ’fast’ or
|
||||
’best’, in increasing complexity and slowness
|
||||
order. Default is ’fast’. Internally, alpha
|
||||
filtering is performed using four possible predictions
|
||||
(none, horizontal, vertical, gradient). The
|
||||
’best’ mode will try each mode in turn and pick
|
||||
the one which gives the smaller size. The ’fast’
|
||||
mode will just try to form an a priori guess without testing
|
||||
all modes.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_method</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the algorithm used for
|
||||
alpha compression: 0 or 1. Algorithm 0 denotes no
|
||||
compression, 1 uses WebP lossless format for compression.
|
||||
The default is 1.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−exact</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Preserve RGB values
|
||||
in transparent area. The default is off, to help
|
||||
compressibility.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−blend_alpha</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">This option blends the alpha
|
||||
channel (if present) with the source using the background
|
||||
color specified in hexadecimal as 0xrrggbb. The alpha
|
||||
channel is afterward reset to the opaque value 255.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−noalpha</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Using this option will discard
|
||||
the alpha channel.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−hint</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the hint about input
|
||||
image type. Possible values are: <b>photo</b>,
|
||||
<b>picture</b> or <b>graph</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>exif</b>,
|
||||
<b>icc</b>, <b>xmp</b>. The default is <b>none</b>.</p>
|
||||
|
||||
<p style="margin-left:22%; margin-top: 1em">Note: each
|
||||
input format may not support all combinations.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−noasm</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="53%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Disable all
|
||||
assembly optimizations.</p></td>
|
||||
<td width="25%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp −q
|
||||
50 -lossless picture.png −o picture_lossless.webp <br>
|
||||
cwebp −q 70 picture_with_alpha.png −o
|
||||
picture_with_alpha.webp <br>
|
||||
cwebp −sns 70 −f 50 −size 60000
|
||||
picture.png −o picture.webp <br>
|
||||
cwebp −o picture.webp −−
|
||||
−−−picture.png</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>(1),
|
||||
<b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,340 @@
|
||||
CWEBP(1) CWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
cwebp - compress an image file to a WebP file
|
||||
|
||||
SYNOPSIS
|
||||
cwebp [options] input_file -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the cwebp command.
|
||||
|
||||
cwebp compresses an image using the WebP format. Input format can be
|
||||
either PNG, JPEG, TIFF, WebP or raw Y'CbCr samples. Note: Animated PNG
|
||||
and WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, cwebp will
|
||||
perform compression but only report statistics. Using "-" as
|
||||
output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with a '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-H, -longhelp
|
||||
A summary of all the possible options.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossless
|
||||
Encode the image without any loss. For images with fully trans-
|
||||
parent area, the invisible pixel values (R/G/B or Y/U/V) will be
|
||||
preserved only if the -exact option is used.
|
||||
|
||||
-near_lossless int
|
||||
Specify the level of near-lossless image preprocessing. This
|
||||
option adjusts pixel values to help compressibility, but has
|
||||
minimal impact on the visual quality. It triggers lossless com-
|
||||
pression mode automatically. The range is 0 (maximum preprocess-
|
||||
ing) to 100 (no preprocessing, the default). The typical value
|
||||
is around 60. Note that lossy with -q 100 can at times yield
|
||||
better results.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossy compression (default), a small factor produces
|
||||
a smaller file with lower quality. Best quality is achieved by
|
||||
using a value of 100.
|
||||
In case of lossless compression (specified by the -lossless
|
||||
option), a small factor enables faster compression speed, but
|
||||
produces a larger file. Maximum compression is achieved by
|
||||
using a value of 100.
|
||||
|
||||
-z int Switch on lossless compression mode with the specified level
|
||||
between 0 and 9, with level 0 being the fastest, 9 being the
|
||||
slowest. Fast mode produces larger file size than slower ones. A
|
||||
good default is -z 6. This option is actually a shortcut for
|
||||
some predefined settings for quality and method. If options -q
|
||||
or -m are subsequently used, they will invalidate the effect of
|
||||
this option.
|
||||
|
||||
-alpha_q int
|
||||
Specify the compression factor for alpha compression between 0
|
||||
and 100. Lossless compression of alpha is achieved using a
|
||||
value of 100, while the lower values result in a lossy compres-
|
||||
sion. The default is 100.
|
||||
|
||||
-preset string
|
||||
Specify a set of pre-defined parameters to suit a particular
|
||||
type of source material. Possible values are: default, photo,
|
||||
picture, drawing, icon, text. Since -preset overwrites the other
|
||||
parameters' values (except the -q one), this option should
|
||||
preferably appear first in the order of the arguments.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and
|
||||
decide on the quality gain. Lower value can result in faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the source to a rectangle with top-left corner at coordi-
|
||||
nates (x_position, y_position) and size width x height. This
|
||||
cropping area must be fully contained within the source rectan-
|
||||
gle. Note: the cropping is applied before any scaling.
|
||||
|
||||
-resize width height
|
||||
Resize the source to a rectangle with size width x height. If
|
||||
either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio. Note:
|
||||
scaling is applied after cropping.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-low_memory
|
||||
Reduce memory usage of lossy encoding by saving four times the
|
||||
compressed size (typically). This will make the encoding slower
|
||||
and the output slightly different in size and distortion. This
|
||||
flag is only effective for methods 3 and up, and is off by
|
||||
default. Note that leaving this flag off will have some side
|
||||
effects on the bitstream: it forces certain bitstream features
|
||||
like number of partitions (forced to 1). Note that a more
|
||||
detailed report of bitstream size is printed by cwebp when using
|
||||
this option.
|
||||
|
||||
|
||||
LOSSY OPTIONS
|
||||
These options are only effective when doing lossy encoding (the
|
||||
default, with or without alpha).
|
||||
|
||||
|
||||
-size int
|
||||
Specify a target size (in bytes) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-psnr float
|
||||
Specify a target PSNR (in dB) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-pass int
|
||||
Set a maximum number of passes to use during the dichotomy used
|
||||
by options -size or -psnr. Maximum value is 10, default is 1.
|
||||
If options -size or -psnr were used, but -pass wasn't specified,
|
||||
a default value of '6' passes will be used.
|
||||
|
||||
-qrange int int
|
||||
Specifies the permissible interval for the quality factor. This
|
||||
is particularly useful when using multi-pass (-size or -psnr
|
||||
options). Default is 0 100. If the quality factor is outside
|
||||
this range, it will be clamped. If the minimum value must be
|
||||
less or equal to the maximum one.
|
||||
|
||||
-af Turns auto-filter on. This algorithm will spend additional time
|
||||
optimizing the filtering strength to reach a well-balanced qual-
|
||||
ity.
|
||||
|
||||
-jpeg_like
|
||||
Change the internal parameter mapping to better match the
|
||||
expected size of JPEG compression. This flag will generally pro-
|
||||
duce an output file of similar size to its JPEG equivalent (for
|
||||
the same -q setting), but with less visual distortion.
|
||||
|
||||
|
||||
Advanced options:
|
||||
|
||||
|
||||
-f int Specify the strength of the deblocking filter, between 0 (no
|
||||
filtering) and 100 (maximum filtering). A value of 0 will turn
|
||||
off any filtering. Higher value will increase the strength of
|
||||
the filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear. Typical
|
||||
values are usually in the range of 20 to 50.
|
||||
|
||||
-sharpness int
|
||||
Specify the sharpness of the filtering (if used). Range is 0
|
||||
(sharpest) to 7 (least sharp). Default is 0.
|
||||
|
||||
-strong
|
||||
Use strong filtering (if filtering is being used thanks to the
|
||||
-f option). Strong filtering is on by default.
|
||||
|
||||
-nostrong
|
||||
Disable strong filtering (if filtering is being used thanks to
|
||||
the -f option) and use simple filtering instead.
|
||||
|
||||
-sharp_yuv
|
||||
Use more accurate and sharper RGB->YUV conversion if needed.
|
||||
Note that this process is slower than the default 'fast'
|
||||
RGB->YUV conversion.
|
||||
|
||||
-sns int
|
||||
Specify the amplitude of the spatial noise shaping. Spatial
|
||||
noise shaping (or sns for short) refers to a general collection
|
||||
of built-in algorithms used to decide which area of the picture
|
||||
should use relatively less bits, and where else to better trans-
|
||||
fer these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is 50.
|
||||
|
||||
-segments int
|
||||
Change the number of partitions to use during the segmentation
|
||||
of the sns algorithm. Segments should be in range 1 to 4.
|
||||
Default value is 4. This option has no effect for methods 3 and
|
||||
up, unless -low_memory is used.
|
||||
|
||||
-partition_limit int
|
||||
Degrade quality by limiting the number of bits used by some mac-
|
||||
roblocks. Range is 0 (no degradation, the default) to 100 (full
|
||||
degradation). Useful values are usually around 30-70 for moder-
|
||||
ately large images. In the VP8 format, the so-called control
|
||||
partition has a limit of 512k and is used to store the following
|
||||
information: whether the macroblock is skipped, which segment it
|
||||
belongs to, whether it is coded as intra 4x4 or intra 16x16
|
||||
mode, and finally the prediction modes to use for each of the
|
||||
sub-blocks. For a very large image, 512k only leaves room to
|
||||
few bits per 16x16 macroblock. The absolute minimum is 4 bits
|
||||
per macroblock. Skip, segment, and mode information can use up
|
||||
almost all these 4 bits (although the case is unlikely), which
|
||||
is problematic for very large images. The partition_limit factor
|
||||
controls how frequently the most bit-costly mode (intra 4x4)
|
||||
will be used. This is useful in case the 512k limit is reached
|
||||
and the following message is displayed: Error code: 6 (PARTI-
|
||||
TION0_OVERFLOW: Partition #0 is too big to fit 512k). If using
|
||||
-partition_limit is not enough to meet the 512k constraint, one
|
||||
should use less segments in order to save more header bits per
|
||||
macroblock. See the -segments option.
|
||||
|
||||
|
||||
LOGGING OPTIONS
|
||||
These options control the level of output:
|
||||
|
||||
-v Print extra information (encoding time in particular).
|
||||
|
||||
-print_psnr
|
||||
Compute and report average PSNR (Peak-Signal-To-Noise ratio).
|
||||
|
||||
-print_ssim
|
||||
Compute and report average SSIM (structural similarity metric,
|
||||
see https://en.wikipedia.org/wiki/SSIM for additional details).
|
||||
|
||||
-print_lsim
|
||||
Compute and report local similarity metric (sum of lowest error
|
||||
amongst the collocated pixel neighbors).
|
||||
|
||||
-progress
|
||||
Report encoding progress in percent.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-short Only print brief information (output file size and PSNR) for
|
||||
testing purposes.
|
||||
|
||||
-map int
|
||||
Output additional ASCII-map of encoding information. Possible
|
||||
map values range from 1 to 6. This is only meant to help debug-
|
||||
ging.
|
||||
|
||||
|
||||
ADDITIONAL OPTIONS
|
||||
More advanced options are:
|
||||
|
||||
-s width height
|
||||
Specify that the input file actually consists of raw Y'CbCr sam-
|
||||
ples following the ITU-R BT.601 recommendation, in 4:2:0 linear
|
||||
format. The luma plane has size width x height.
|
||||
|
||||
-pre int
|
||||
Specify some preprocessing steps. Using a value of '2' will
|
||||
trigger quality-dependent pseudo-random dithering during
|
||||
RGBA->YUVA conversion (lossy compression only).
|
||||
|
||||
-alpha_filter string
|
||||
Specify the predictive filtering method for the alpha plane. One
|
||||
of 'none', 'fast' or 'best', in increasing complexity and slow-
|
||||
ness order. Default is 'fast'. Internally, alpha filtering is
|
||||
performed using four possible predictions (none, horizontal,
|
||||
vertical, gradient). The 'best' mode will try each mode in turn
|
||||
and pick the one which gives the smaller size. The 'fast' mode
|
||||
will just try to form an a priori guess without testing all
|
||||
modes.
|
||||
|
||||
-alpha_method int
|
||||
Specify the algorithm used for alpha compression: 0 or 1. Algo-
|
||||
rithm 0 denotes no compression, 1 uses WebP lossless format for
|
||||
compression. The default is 1.
|
||||
|
||||
-exact Preserve RGB values in transparent area. The default is off, to
|
||||
help compressibility.
|
||||
|
||||
-blend_alpha int
|
||||
This option blends the alpha channel (if present) with the
|
||||
source using the background color specified in hexadecimal as
|
||||
0xrrggbb. The alpha channel is afterward reset to the opaque
|
||||
value 255.
|
||||
|
||||
-noalpha
|
||||
Using this option will discard the alpha channel.
|
||||
|
||||
-hint string
|
||||
Specify the hint about input image type. Possible values are:
|
||||
photo, picture or graph.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, exif, icc, xmp.
|
||||
The default is none.
|
||||
|
||||
Note: each input format may not support all combinations.
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
cwebp -q 50 -lossless picture.png -o picture_lossless.webp
|
||||
cwebp -q 70 picture_with_alpha.png -o picture_with_alpha.webp
|
||||
cwebp -sns 70 -f 50 -size 60000 picture.png -o picture.webp
|
||||
cwebp -o picture.webp -- ---picture.png
|
||||
|
||||
|
||||
AUTHORS
|
||||
cwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
dwebp(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
March 17, 2022 CWEBP(1)
|
||||
@@ -0,0 +1,386 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:54 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>DWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>DWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp −
|
||||
decompress a WebP file to an image file</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
[<i>options</i>] <i>input_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>dwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
decompresses WebP files into PNG, PAM, PPM or PGM images.
|
||||
Note: Animated WebP files are not supported.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−h</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print usage
|
||||
summary.</p> </td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−o</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
file (as PNG format by default). Using "-" as
|
||||
output name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "−", the data will be read
|
||||
from <i>stdin</i> instead of a file.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−bmp</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to uncompressed BMP.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−tiff</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to uncompressed TIFF.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−pam</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PAM (retains alpha).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−ppm</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PPM (discards alpha).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−pgm</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PGM. The output consists of luma/chroma samples
|
||||
instead of RGB, using the IMC4 layout. This option is mainly
|
||||
for verification and debugging purposes.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−yuv</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to raw YUV. The output consists of
|
||||
luma/chroma-U/chroma-V samples instead of RGB, saved
|
||||
sequentially as individual planes. This option is mainly for
|
||||
verification and debugging purposes.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofancy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the fancy
|
||||
upscaler for YUV420. This may lead to jaggy edges
|
||||
(especially the red ones), but should be faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofilter</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the in-loop
|
||||
filtering process even if it is required by the bitstream.
|
||||
This may produce visible blocks on the non-compliant output,
|
||||
but it will make the decoding faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−dither</b>
|
||||
<i>strength</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a dithering
|
||||
<b>strength</b> between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding
|
||||
banding artifacts.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_dither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If the compressed file contains
|
||||
a transparency plane that was quantized during compression,
|
||||
this flag will allow dithering the reconstructed plane in
|
||||
order to generate smoother transparency gradients.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nodither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable all dithering
|
||||
(default).</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use multi-threading
|
||||
for decoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−crop</b>
|
||||
<i>x_position y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the decoded picture to a
|
||||
rectangle with top-left corner at coordinates
|
||||
(<b>x_position</b>, <b>y_position</b>) and size <b>width</b>
|
||||
x <b>height</b>. This cropping area must be fully contained
|
||||
within the source rectangle. The top-left corner will be
|
||||
snapped to even coordinates if needed. This option is meant
|
||||
to reduce the memory needed for cropping large images. Note:
|
||||
the cropping is applied <i>before</i> any scaling.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−flip</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Flip decoded image
|
||||
vertically (can be useful for OpenGL textures for
|
||||
instance).</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−resize</b>,
|
||||
<b>−scale</b> <i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Rescale the decoded picture to
|
||||
dimension <b>width</b> x <b>height</b>. This option is
|
||||
mostly intended to reducing the memory needed to decode
|
||||
large images, when only a small version is needed
|
||||
(thumbnail, preview, etc.). Note: scaling is applied
|
||||
<i>after</i> cropping. If either (but not both) of the
|
||||
<b>width</b> or <b>height</b> parameters is 0, the value
|
||||
will be calculated preserving the aspect-ratio.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information (decoding time in particular).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−noasm</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Disable all
|
||||
assembly optimizations.</p></td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp
|
||||
picture.webp −o output.png <br>
|
||||
dwebp picture.webp −ppm −o output.ppm <br>
|
||||
dwebp −o output.ppm −−
|
||||
−−−picture.webp <br>
|
||||
cat picture.webp | dwebp −o − −−
|
||||
− > output.ppm</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>gif2webp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>Output file
|
||||
format details</b> <br>
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html <br>
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html <br>
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html <br>
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,142 @@
|
||||
DWEBP(1) DWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
dwebp - decompress a WebP file to an image file
|
||||
|
||||
SYNOPSIS
|
||||
dwebp [options] input_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the dwebp command.
|
||||
|
||||
dwebp decompresses WebP files into PNG, PAM, PPM or PGM images. Note:
|
||||
Animated WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-h Print usage summary.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-o string
|
||||
Specify the name of the output file (as PNG format by default).
|
||||
Using "-" as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from stdin instead
|
||||
of a file.
|
||||
|
||||
-bmp Change the output format to uncompressed BMP.
|
||||
|
||||
-tiff Change the output format to uncompressed TIFF.
|
||||
|
||||
-pam Change the output format to PAM (retains alpha).
|
||||
|
||||
-ppm Change the output format to PPM (discards alpha).
|
||||
|
||||
-pgm Change the output format to PGM. The output consists of
|
||||
luma/chroma samples instead of RGB, using the IMC4 layout. This
|
||||
option is mainly for verification and debugging purposes.
|
||||
|
||||
-yuv Change the output format to raw YUV. The output consists of
|
||||
luma/chroma-U/chroma-V samples instead of RGB, saved sequen-
|
||||
tially as individual planes. This option is mainly for verifica-
|
||||
tion and debugging purposes.
|
||||
|
||||
-nofancy
|
||||
Don't use the fancy upscaler for YUV420. This may lead to jaggy
|
||||
edges (especially the red ones), but should be faster.
|
||||
|
||||
-nofilter
|
||||
Don't use the in-loop filtering process even if it is required
|
||||
by the bitstream. This may produce visible blocks on the non-
|
||||
compliant output, but it will make the decoding faster.
|
||||
|
||||
-dither strength
|
||||
Specify a dithering strength between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding band-
|
||||
ing artifacts.
|
||||
|
||||
-alpha_dither
|
||||
If the compressed file contains a transparency plane that was
|
||||
quantized during compression, this flag will allow dithering the
|
||||
reconstructed plane in order to generate smoother transparency
|
||||
gradients.
|
||||
|
||||
-nodither
|
||||
Disable all dithering (default).
|
||||
|
||||
-mt Use multi-threading for decoding, if possible.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the decoded picture to a rectangle with top-left corner at
|
||||
coordinates (x_position, y_position) and size width x height.
|
||||
This cropping area must be fully contained within the source
|
||||
rectangle. The top-left corner will be snapped to even coordi-
|
||||
nates if needed. This option is meant to reduce the memory
|
||||
needed for cropping large images. Note: the cropping is applied
|
||||
before any scaling.
|
||||
|
||||
-flip Flip decoded image vertically (can be useful for OpenGL textures
|
||||
for instance).
|
||||
|
||||
-resize, -scale width height
|
||||
Rescale the decoded picture to dimension width x height. This
|
||||
option is mostly intended to reducing the memory needed to
|
||||
decode large images, when only a small version is needed (thumb-
|
||||
nail, preview, etc.). Note: scaling is applied after cropping.
|
||||
If either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-v Print extra information (decoding time in particular).
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
dwebp picture.webp -o output.png
|
||||
dwebp picture.webp -ppm -o output.ppm
|
||||
dwebp -o output.ppm -- ---picture.webp
|
||||
cat picture.webp | dwebp -o - -- - > output.ppm
|
||||
|
||||
|
||||
AUTHORS
|
||||
dwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), gif2webp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
Output file format details
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info
|
||||
|
||||
|
||||
|
||||
November 17, 2021 DWEBP(1)
|
||||
@@ -0,0 +1,341 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:54 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>GIF2WEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>GIF2WEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp
|
||||
− Convert a GIF image to WebP</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
[<i>options</i>] <i>input_file.gif −o
|
||||
output_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>gif2webp</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
converts a GIF image to a WebP image.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
−o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>gif2webp</b> will perform
|
||||
conversion but only report statistics. Using
|
||||
"−" as output name will direct output to
|
||||
’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "−", the data will be read
|
||||
from <i>stdin</i> instead of a file.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Usage information.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−lossy</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Encode the image
|
||||
using lossy compression.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mixed</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Mixed compression
|
||||
mode: optimize compression of the image by picking either
|
||||
lossy or lossless compression for each frame
|
||||
heuristically.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−q</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossless compression (default), a small factor
|
||||
enables faster compression speed, but produces a larger
|
||||
file. Maximum compression is achieved by using a value of
|
||||
100. <br>
|
||||
In case of lossy compression (specified by the −lossy
|
||||
option), a small factor produces a smaller file with lower
|
||||
quality. Best quality is achieved by using a value of
|
||||
100.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−m</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
compression method to use. This parameter controls the trade
|
||||
off between encoding speed and the compressed file size and
|
||||
quality. Possible values range from 0 to 6. Default value is
|
||||
4. When higher values are used, the encoder will spend more
|
||||
time inspecting additional encoding possibilities and decide
|
||||
on the quality gain. Lower value can result is faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−min_size</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode image to achieve
|
||||
smallest size. This disables key frame insertion and picks
|
||||
the dispose method resulting in the smallest output for each
|
||||
frame. It uses lossless compression by default, but can be
|
||||
combined with −q, −m, −lossy or
|
||||
−mixed options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−kmin</b> <i>int</i>
|
||||
<b><br>
|
||||
−kmax</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the minimum and maximum
|
||||
distance between consecutive key frames (independently
|
||||
decodable frames) in the output animation. The tool will
|
||||
insert some key frames into the output animation as needed
|
||||
so that this criteria is satisfied. <br>
|
||||
A ’kmax’ value of 0 will turn off insertion of
|
||||
key frames. A ’kmax’ value of 1 will result in
|
||||
all frames being key frames. ’kmin’ value is not
|
||||
taken into account in both these special cases. Typical
|
||||
values are in the range 3 to 30. Default values are kmin =
|
||||
9, kmax = 17 for lossless compression and kmin = 3, kmax = 5
|
||||
for lossy compression. <br>
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50). <br>
|
||||
When lower values are used, more frames will be converted to
|
||||
key frames. This may lead to smaller number of frames
|
||||
required to decode a frame on average, thereby improving the
|
||||
decoding performance. But this may lead to slightly bigger
|
||||
file sizes. Higher values may lead to worse decoding
|
||||
performance, but smaller file sizes. <br>
|
||||
Some restrictions: <br>
|
||||
(i) kmin < kmax, <br>
|
||||
(ii) kmin >= kmax / 2 + 1 and <br>
|
||||
(iii) kmax - kmin <= 30. <br>
|
||||
If any of these restrictions are not met, they will be
|
||||
enforced automatically.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>icc</b>,
|
||||
<b>xmp</b>. The default is <b>xmp</b>.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−f</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">For lossy encoding
|
||||
only (specified by the −lossy option). Specify the
|
||||
strength of the deblocking filter, between 0 (no filtering)
|
||||
and 100 (maximum filtering). A value of 0 will turn off any
|
||||
filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear.
|
||||
Typical values are usually in the range of 20 to 50.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use multi-threading
|
||||
for encoding, if possible.</p></td>
|
||||
</table>
|
||||
|
||||
|
||||
<p style="margin-left:11%;"><b>−loop_compatibility</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If enabled, handle the loop
|
||||
information in a compatible fashion for Chrome version prior
|
||||
to M62 (inclusive) and Firefox.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information.</p> </td>
|
||||
<td width="42%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<td width="42%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp
|
||||
picture.gif −o picture.webp <br>
|
||||
gif2webp −q 70 picture.gif −o picture.webp <br>
|
||||
gif2webp −lossy −m 3 picture.gif −o
|
||||
picture_lossy.webp <br>
|
||||
gif2webp −lossy −f 50 picture.gif −o
|
||||
picture.webp <br>
|
||||
gif2webp −q 70 −o picture.webp −−
|
||||
−−−picture.gif <br>
|
||||
cat picture.gif | gif2webp −o − −−
|
||||
− > output.webp</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Urvang Joshi <urvang@google.com>,
|
||||
for the Debian project (and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>dwebp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,152 @@
|
||||
GIF2WEBP(1) GIF2WEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
gif2webp - Convert a GIF image to WebP
|
||||
|
||||
SYNOPSIS
|
||||
gif2webp [options] input_file.gif -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the gif2webp command.
|
||||
|
||||
gif2webp converts a GIF image to a WebP image.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, gif2webp
|
||||
will perform conversion but only report statistics. Using "-"
|
||||
as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from stdin instead
|
||||
of a file.
|
||||
|
||||
-h, -help
|
||||
Usage information.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossy Encode the image using lossy compression.
|
||||
|
||||
-mixed Mixed compression mode: optimize compression of the image by
|
||||
picking either lossy or lossless compression for each frame
|
||||
heuristically.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossless compression (default), a small factor
|
||||
enables faster compression speed, but produces a larger file.
|
||||
Maximum compression is achieved by using a value of 100.
|
||||
In case of lossy compression (specified by the -lossy option), a
|
||||
small factor produces a smaller file with lower quality. Best
|
||||
quality is achieved by using a value of 100.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and
|
||||
decide on the quality gain. Lower value can result is faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.
|
||||
|
||||
-min_size
|
||||
Encode image to achieve smallest size. This disables key frame
|
||||
insertion and picks the dispose method resulting in the smallest
|
||||
output for each frame. It uses lossless compression by default,
|
||||
but can be combined with -q, -m, -lossy or -mixed options.
|
||||
|
||||
-kmin int
|
||||
|
||||
-kmax int
|
||||
Specify the minimum and maximum distance between consecutive key
|
||||
frames (independently decodable frames) in the output animation.
|
||||
The tool will insert some key frames into the output animation
|
||||
as needed so that this criteria is satisfied.
|
||||
A 'kmax' value of 0 will turn off insertion of key frames. A
|
||||
'kmax' value of 1 will result in all frames being key frames.
|
||||
'kmin' value is not taken into account in both these special
|
||||
cases. Typical values are in the range 3 to 30. Default values
|
||||
are kmin = 9, kmax = 17 for lossless compression and kmin = 3,
|
||||
kmax = 5 for lossy compression.
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50).
|
||||
When lower values are used, more frames will be converted to key
|
||||
frames. This may lead to smaller number of frames required to
|
||||
decode a frame on average, thereby improving the decoding per-
|
||||
formance. But this may lead to slightly bigger file sizes.
|
||||
Higher values may lead to worse decoding performance, but
|
||||
smaller file sizes.
|
||||
Some restrictions:
|
||||
(i) kmin < kmax,
|
||||
(ii) kmin >= kmax / 2 + 1 and
|
||||
(iii) kmax - kmin <= 30.
|
||||
If any of these restrictions are not met, they will be enforced
|
||||
automatically.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, icc, xmp. The
|
||||
default is xmp.
|
||||
|
||||
-f int For lossy encoding only (specified by the -lossy option). Spec-
|
||||
ify the strength of the deblocking filter, between 0 (no filter-
|
||||
ing) and 100 (maximum filtering). A value of 0 will turn off
|
||||
any filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The higher
|
||||
the value the smoother the picture will appear. Typical values
|
||||
are usually in the range of 20 to 50.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-loop_compatibility
|
||||
If enabled, handle the loop information in a compatible fashion
|
||||
for Chrome version prior to M62 (inclusive) and Firefox.
|
||||
|
||||
-v Print extra information.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
gif2webp picture.gif -o picture.webp
|
||||
gif2webp -q 70 picture.gif -o picture.webp
|
||||
gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp
|
||||
gif2webp -lossy -f 50 picture.gif -o picture.webp
|
||||
gif2webp -q 70 -o picture.webp -- ---picture.gif
|
||||
cat picture.gif | gif2webp -o - -- - > output.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
gif2webp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Urvang Joshi <urvang@google.com>, for
|
||||
the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), dwebp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 GIF2WEBP(1)
|
||||
@@ -0,0 +1,245 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:55 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>IMG2WEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>IMG2WEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#FILE-LEVEL OPTIONS">FILE-LEVEL OPTIONS</a><br>
|
||||
<a href="#PER-FRAME OPTIONS">PER-FRAME OPTIONS</a><br>
|
||||
<a href="#EXAMPLE">EXAMPLE</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">img2webp
|
||||
− create animated WebP file from a sequence of input
|
||||
images.</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
[file_options] [[frame_options] frame_file]... <b><br>
|
||||
img2webp argument_file_name</b></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>img2webp</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
compresses a sequence of images using the animated WebP
|
||||
format. Input images can either be PNG, JPEG, TIFF or WebP.
|
||||
If a single file name (not starting with the character
|
||||
’−’) is supplied as the argument, the
|
||||
command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number
|
||||
of arguments.</p>
|
||||
|
||||
<a name="FILE-LEVEL OPTIONS"></a>
|
||||
<h2>FILE-LEVEL OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The file-level
|
||||
options are applied at the beginning of the compression
|
||||
process, before the input frames are read. <b><br>
|
||||
−o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−min_size</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode images to achieve
|
||||
smallest size. This disables key frame insertion and picks
|
||||
the parameters resulting in the smallest output for each
|
||||
frame. It uses lossless compression by default, but can be
|
||||
combined with −q, −m, −lossy or
|
||||
−mixed options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−kmin</b> <i>int</i>
|
||||
<b><br>
|
||||
−kmax</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the minimum and maximum
|
||||
distance between consecutive key frames (independently
|
||||
decodable frames) in the output animation. The tool will
|
||||
insert some key frames into the output animation as needed
|
||||
so that this criteria is satisfied. <b><br>
|
||||
−mixed</b> Mixed compression mode: optimize
|
||||
compression of the image by picking either lossy or lossless
|
||||
compression for each frame heuristically. This global option
|
||||
disables the local option <b>-lossy</b> and <b>-lossless</b>
|
||||
.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−loop</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specifies the number of times
|
||||
the animation should loop. Using ’0’ means
|
||||
’loop indefinitely’.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="24%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Be more
|
||||
verbose.</p> </td>
|
||||
<td width="54%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version numbers of
|
||||
the relevant libraries used.</p>
|
||||
|
||||
<a name="PER-FRAME OPTIONS"></a>
|
||||
<h2>PER-FRAME OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The per-frame
|
||||
options are applied for the images following as arguments in
|
||||
the command line. They can be modified any number of times
|
||||
preceding each particular input image.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−d</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="66%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the image
|
||||
duration in milliseconds.</p></td>
|
||||
<td width="12%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−lossless,
|
||||
−lossy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compress the next image(s)
|
||||
using lossless or lossy compression mode. The default mode
|
||||
is lossless.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−q</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
between 0 and 100. The default is 75.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−m</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
compression method to use. This parameter controls the trade
|
||||
off between encoding speed and the compressed file size and
|
||||
quality. Possible values range from 0 to 6. Default value is
|
||||
4.</p> </td>
|
||||
</table>
|
||||
|
||||
<a name="EXAMPLE"></a>
|
||||
<h2>EXAMPLE</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">img2webp -loop
|
||||
2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp</p>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>img2webp</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>(1),
|
||||
<b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,108 @@
|
||||
IMG2WEBP(1) IMG2WEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
img2webp - create animated WebP file from a sequence of input images.
|
||||
|
||||
SYNOPSIS
|
||||
img2webp [file_options] [[frame_options] frame_file]...
|
||||
img2webp argument_file_name
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the img2webp command.
|
||||
|
||||
img2webp compresses a sequence of images using the animated WebP for-
|
||||
mat. Input images can either be PNG, JPEG, TIFF or WebP. If a single
|
||||
file name (not starting with the character '-') is supplied as the
|
||||
argument, the command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number of argu-
|
||||
ments.
|
||||
|
||||
FILE-LEVEL OPTIONS
|
||||
The file-level options are applied at the beginning of the compression
|
||||
process, before the input frames are read.
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file.
|
||||
|
||||
-min_size
|
||||
Encode images to achieve smallest size. This disables key frame
|
||||
insertion and picks the parameters resulting in the smallest
|
||||
output for each frame. It uses lossless compression by default,
|
||||
but can be combined with -q, -m, -lossy or -mixed options.
|
||||
|
||||
-kmin int
|
||||
|
||||
-kmax int
|
||||
Specify the minimum and maximum distance between consecutive key
|
||||
frames (independently decodable frames) in the output animation.
|
||||
The tool will insert some key frames into the output animation
|
||||
as needed so that this criteria is satisfied.
|
||||
-mixed Mixed compression mode: optimize compression of the image
|
||||
by picking either lossy or lossless compression for each frame
|
||||
heuristically. This global option disables the local option
|
||||
-lossy and -lossless .
|
||||
|
||||
-loop int
|
||||
Specifies the number of times the animation should loop. Using
|
||||
'0' means 'loop indefinitely'.
|
||||
|
||||
-v Be more verbose.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-version
|
||||
Print the version numbers of the relevant libraries used.
|
||||
|
||||
|
||||
PER-FRAME OPTIONS
|
||||
The per-frame options are applied for the images following as arguments
|
||||
in the command line. They can be modified any number of times preceding
|
||||
each particular input image.
|
||||
|
||||
-d int Specify the image duration in milliseconds.
|
||||
|
||||
-lossless, -lossy
|
||||
Compress the next image(s) using lossless or lossy compression
|
||||
mode. The default mode is lossless.
|
||||
|
||||
-q float
|
||||
Specify the compression factor between 0 and 100. The default is
|
||||
75.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4.
|
||||
|
||||
|
||||
EXAMPLE
|
||||
img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
AUTHORS
|
||||
img2webp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
webpmux(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
January 5, 2022 IMG2WEBP(1)
|
||||
@@ -0,0 +1,512 @@
|
||||
# WebP tools
|
||||
|
||||
## Encoding tool
|
||||
|
||||
The examples/ directory contains tools for encoding (cwebp) and decoding (dwebp)
|
||||
images.
|
||||
|
||||
The easiest use should look like:
|
||||
|
||||
```shell
|
||||
cwebp input.png -q 80 -o output.webp
|
||||
```
|
||||
|
||||
which will convert the input file to a WebP file using a quality factor of 80 on
|
||||
a 0->100 scale (0 being the lowest quality, 100 being the best. Default value is
|
||||
75).
|
||||
|
||||
You might want to try the `-lossless` flag too, which will compress the source
|
||||
(in RGBA format) without any loss. The `-q` quality parameter will in this case
|
||||
control the amount of processing time spent trying to make the output file as
|
||||
small as possible.
|
||||
|
||||
A longer list of options is available using the `-longhelp` command line flag:
|
||||
|
||||
```shell
|
||||
> cwebp -longhelp
|
||||
Usage:
|
||||
cwebp [-preset <...>] [options] in_file [-o out_file]
|
||||
```
|
||||
|
||||
If input size (-s) for an image is not specified, it is assumed to be a PNG,
|
||||
JPEG, TIFF or WebP file. Note: Animated PNG and WebP files are not supported.
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-h / -help ............. short help
|
||||
-H / -longhelp ......... long help
|
||||
-q <float> ............. quality factor (0:small..100:big), default=75
|
||||
-alpha_q <int> ......... transparency-compression quality (0..100),
|
||||
default=100
|
||||
-preset <string> ....... preset setting, one of:
|
||||
default, photo, picture,
|
||||
drawing, icon, text
|
||||
-preset must come first, as it overwrites other parameters
|
||||
-z <int> ............... activates lossless preset with given
|
||||
level in [0:fast, ..., 9:slowest]
|
||||
|
||||
-m <int> ............... compression method (0=fast, 6=slowest), default=4
|
||||
-segments <int> ........ number of segments to use (1..4), default=4
|
||||
-size <int> ............ target size (in bytes)
|
||||
-psnr <float> .......... target PSNR (in dB. typically: 42)
|
||||
|
||||
-s <int> <int> ......... input size (width x height) for YUV
|
||||
-sns <int> ............. spatial noise shaping (0:off, 100:max), default=50
|
||||
-f <int> ............... filter strength (0=off..100), default=60
|
||||
-sharpness <int> ....... filter sharpness (0:most .. 7:least sharp), default=0
|
||||
-strong ................ use strong filter instead of simple (default)
|
||||
-nostrong .............. use simple filter instead of strong
|
||||
-sharp_yuv ............. use sharper (and slower) RGB->YUV conversion
|
||||
-partition_limit <int> . limit quality to fit the 512k limit on
|
||||
the first partition (0=no degradation ... 100=full)
|
||||
-pass <int> ............ analysis pass number (1..10)
|
||||
-qrange <min> <max> .... specifies the permissible quality range
|
||||
(default: 0 100)
|
||||
-crop <x> <y> <w> <h> .. crop picture with the given rectangle
|
||||
-resize <w> <h> ........ resize picture (*after* any cropping)
|
||||
-mt .................... use multi-threading if available
|
||||
-low_memory ............ reduce memory usage (slower encoding)
|
||||
-map <int> ............. print map of extra info
|
||||
-print_psnr ............ prints averaged PSNR distortion
|
||||
-print_ssim ............ prints averaged SSIM distortion
|
||||
-print_lsim ............ prints local-similarity distortion
|
||||
-d <file.pgm> .......... dump the compressed output (PGM file)
|
||||
-alpha_method <int> .... transparency-compression method (0..1), default=1
|
||||
-alpha_filter <string> . predictive filtering for alpha plane,
|
||||
one of: none, fast (default) or best
|
||||
-exact ................. preserve RGB values in transparent area, default=off
|
||||
-blend_alpha <hex> ..... blend colors against background color
|
||||
expressed as RGB values written in
|
||||
hexadecimal, e.g. 0xc0e0d0 for red=0xc0
|
||||
green=0xe0 and blue=0xd0
|
||||
-noalpha ............... discard any transparency information
|
||||
-lossless .............. encode image losslessly, default=off
|
||||
-near_lossless <int> ... use near-lossless image
|
||||
preprocessing (0..100=off), default=100
|
||||
-hint <string> ......... specify image characteristics hint,
|
||||
one of: photo, picture or graph
|
||||
|
||||
-metadata <string> ..... comma separated list of metadata to
|
||||
copy from the input to the output if present.
|
||||
Valid values: all, none (default), exif, icc, xmp
|
||||
|
||||
-short ................. condense printed message
|
||||
-quiet ................. don't print anything
|
||||
-version ............... print version number and exit
|
||||
-noasm ................. disable all assembly optimizations
|
||||
-v ..................... verbose, e.g. print encoding/decoding times
|
||||
-progress .............. report encoding progress
|
||||
```
|
||||
|
||||
Experimental Options:
|
||||
|
||||
```
|
||||
-jpeg_like ............. roughly match expected JPEG size
|
||||
-af .................... auto-adjust filter strength
|
||||
-pre <int> ............. pre-processing filter
|
||||
```
|
||||
|
||||
The main options you might want to try in order to further tune the visual
|
||||
quality are:
|
||||
|
||||
-preset -sns -f -m
|
||||
|
||||
Namely:
|
||||
|
||||
* `preset` will set up a default encoding configuration targeting a particular
|
||||
type of input. It should appear first in the list of options, so that
|
||||
subsequent options can take effect on top of this preset. Default value is
|
||||
'default'.
|
||||
* `sns` will progressively turn on (when going from 0 to 100) some additional
|
||||
visual optimizations (like: segmentation map re-enforcement). This option
|
||||
will balance the bit allocation differently. It tries to take bits from the
|
||||
"easy" parts of the picture and use them in the "difficult" ones instead.
|
||||
Usually, raising the sns value (at fixed -q value) leads to larger files,
|
||||
but with better quality. Typical value is around '75'.
|
||||
* `f` option directly links to the filtering strength used by the codec's
|
||||
in-loop processing. The higher the value, the smoother the highly-compressed
|
||||
area will look. This is particularly useful when aiming at very small files.
|
||||
Typical values are around 20-30. Note that using the option
|
||||
-strong/-nostrong will change the type of filtering. Use "-f 0" to turn
|
||||
filtering off.
|
||||
* `m` controls the trade-off between encoding speed and quality. Default is 4.
|
||||
You can try -m 5 or -m 6 to explore more (time-consuming) encoding
|
||||
possibilities. A lower value will result in faster encoding at the expense
|
||||
of quality.
|
||||
|
||||
## Decoding tool
|
||||
|
||||
There is a decoding sample in examples/dwebp.c which will take a .webp file and
|
||||
decode it to a PNG image file (amongst other formats). This is simply to
|
||||
demonstrate the use of the API. You can verify the file test.webp decodes to
|
||||
exactly the same as test_ref.ppm by using:
|
||||
|
||||
```shell
|
||||
cd examples
|
||||
./dwebp test.webp -ppm -o test.ppm
|
||||
diff test.ppm test_ref.ppm
|
||||
```
|
||||
|
||||
The full list of options is available using -h:
|
||||
|
||||
```shell
|
||||
> dwebp -h
|
||||
Usage: dwebp in_file [options] [-o out_file]
|
||||
```
|
||||
|
||||
Decodes the WebP image file to PNG format [Default]. Note: Animated WebP files
|
||||
are not supported.
|
||||
|
||||
Use following options to convert into alternate image formats:
|
||||
|
||||
```
|
||||
-pam ......... save the raw RGBA samples as a color PAM
|
||||
-ppm ......... save the raw RGB samples as a color PPM
|
||||
-bmp ......... save as uncompressed BMP format
|
||||
-tiff ........ save as uncompressed TIFF format
|
||||
-pgm ......... save the raw YUV samples as a grayscale PGM
|
||||
file with IMC4 layout
|
||||
-yuv ......... save the raw YUV samples in flat layout
|
||||
```
|
||||
|
||||
Other options are:
|
||||
|
||||
```
|
||||
-version ..... print version number and exit
|
||||
-nofancy ..... don't use the fancy YUV420 upscaler
|
||||
-nofilter .... disable in-loop filtering
|
||||
-nodither .... disable dithering
|
||||
-dither <d> .. dithering strength (in 0..100)
|
||||
-alpha_dither use alpha-plane dithering if needed
|
||||
-mt .......... use multi-threading
|
||||
-crop <x> <y> <w> <h> ... crop output with the given rectangle
|
||||
-resize <w> <h> ......... resize output (*after* any cropping)
|
||||
-flip ........ flip the output vertically
|
||||
-alpha ....... only save the alpha plane
|
||||
-incremental . use incremental decoding (useful for tests)
|
||||
-h ........... this help message
|
||||
-v ........... verbose (e.g. print encoding/decoding times)
|
||||
-quiet ....... quiet mode, don't print anything
|
||||
-noasm ....... disable all assembly optimizations
|
||||
```
|
||||
|
||||
## WebP file analysis tool
|
||||
|
||||
`webpinfo` can be used to print out the chunk level structure and bitstream
|
||||
header information of WebP files. It can also check if the files are of valid
|
||||
WebP format.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
webpinfo [options] in_files
|
||||
```
|
||||
|
||||
Note: there could be multiple input files; options must come before input files.
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-version ........... Print version number and exit.
|
||||
-quiet ............. Do not show chunk parsing information.
|
||||
-diag .............. Show parsing error diagnosis.
|
||||
-summary ........... Show chunk stats summary.
|
||||
-bitstream_info .... Parse bitstream header.
|
||||
```
|
||||
|
||||
## Visualization tool
|
||||
|
||||
There's a little self-serve visualization tool called 'vwebp' under the
|
||||
examples/ directory. It uses OpenGL to open a simple drawing window and show a
|
||||
decoded WebP file. It's not yet integrated in the automake build system, but you
|
||||
can try to manually compile it using the recommendations below.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
vwebp in_file [options]
|
||||
```
|
||||
|
||||
Decodes the WebP image file and visualize it using OpenGL
|
||||
|
||||
Options are:
|
||||
|
||||
```
|
||||
-version ..... print version number and exit
|
||||
-noicc ....... don't use the icc profile if present
|
||||
-nofancy ..... don't use the fancy YUV420 upscaler
|
||||
-nofilter .... disable in-loop filtering
|
||||
-dither <int> dithering strength (0..100), default=50
|
||||
-noalphadither disable alpha plane dithering
|
||||
-usebgcolor .. display background color
|
||||
-mt .......... use multi-threading
|
||||
-info ........ print info
|
||||
-h ........... this help message
|
||||
```
|
||||
|
||||
Keyboard shortcuts:
|
||||
|
||||
```
|
||||
'c' ................ toggle use of color profile
|
||||
'b' ................ toggle background color display
|
||||
'i' ................ overlay file information
|
||||
'd' ................ disable blending & disposal (debug)
|
||||
'q' / 'Q' / ESC .... quit
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
Prerequisites:
|
||||
|
||||
1. OpenGL & OpenGL Utility Toolkit (GLUT)
|
||||
|
||||
Linux: `sudo apt-get install freeglut3-dev mesa-common-dev`
|
||||
|
||||
Mac + Xcode: These libraries should be available in the OpenGL / GLUT
|
||||
frameworks.
|
||||
|
||||
Windows: http://freeglut.sourceforge.net/index.php#download
|
||||
|
||||
2. (Optional) qcms (Quick Color Management System)
|
||||
|
||||
1. Download qcms from Mozilla / Chromium:
|
||||
https://hg.mozilla.org/mozilla-central/file/0e7639e3bdfb/gfx/qcms
|
||||
https://source.chromium.org/chromium/chromium/src/+/main:third_party/qcms/;drc=d4a2f8e1ed461d8fc05ed88d1ae2dc94c9773825
|
||||
2. Build and archive the source files as libqcms.a / qcms.lib
|
||||
3. Update makefile.unix / Makefile.vc
|
||||
1. Define WEBP_HAVE_QCMS
|
||||
2. Update include / library paths to reference the qcms directory.
|
||||
|
||||
Build using makefile.unix / Makefile.vc:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/vwebp
|
||||
> nmake /f Makefile.vc CFG=release-static \
|
||||
../obj/x64/release-static/bin/vwebp.exe
|
||||
```
|
||||
|
||||
## Animation creation tool
|
||||
|
||||
The utility `img2webp` can turn a sequence of input images (PNG, JPEG, ...) into
|
||||
an animated WebP file. It offers fine control over duration, encoding modes,
|
||||
etc.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
img2webp [file_options] [[frame_options] frame_file]...
|
||||
```
|
||||
|
||||
File-level options (only used at the start of compression):
|
||||
|
||||
```
|
||||
-min_size ............ minimize size
|
||||
-loop <int> .......... loop count (default: 0, = infinite loop)
|
||||
-kmax <int> .......... maximum number of frame between key-frames
|
||||
(0=only keyframes)
|
||||
-kmin <int> .......... minimum number of frame between key-frames
|
||||
(0=disable key-frames altogether)
|
||||
-mixed ............... use mixed lossy/lossless automatic mode
|
||||
-v ................... verbose mode
|
||||
-h ................... this help
|
||||
-version ............. print version number and exit
|
||||
```
|
||||
|
||||
Per-frame options (only used for subsequent images input):
|
||||
|
||||
```
|
||||
-d <int> ............. frame duration in ms (default: 100)
|
||||
-lossless ........... use lossless mode (default)
|
||||
-lossy ... ........... use lossy mode
|
||||
-q <float> ........... quality
|
||||
-m <int> ............. method to use
|
||||
```
|
||||
|
||||
example: `img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp`
|
||||
|
||||
Note: if a single file name is passed as the argument, the arguments will be
|
||||
tokenized from this file. The file name must not start with the character '-'.
|
||||
|
||||
## Animated GIF conversion
|
||||
|
||||
Animated GIF files can be converted to WebP files with animation using the
|
||||
gif2webp utility available under examples/. The files can then be viewed using
|
||||
vwebp.
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
gif2webp [options] gif_file -o webp_file
|
||||
```
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-h / -help ............. this help
|
||||
-lossy ................. encode image using lossy compression
|
||||
-mixed ................. for each frame in the image, pick lossy
|
||||
or lossless compression heuristically
|
||||
-q <float> ............. quality factor (0:small..100:big)
|
||||
-m <int> ............... compression method (0=fast, 6=slowest)
|
||||
-min_size .............. minimize output size (default:off)
|
||||
lossless compression by default; can be
|
||||
combined with -q, -m, -lossy or -mixed
|
||||
options
|
||||
-kmin <int> ............ min distance between key frames
|
||||
-kmax <int> ............ max distance between key frames
|
||||
-f <int> ............... filter strength (0=off..100)
|
||||
-metadata <string> ..... comma separated list of metadata to
|
||||
copy from the input to the output if present
|
||||
Valid values: all, none, icc, xmp (default)
|
||||
-loop_compatibility .... use compatibility mode for Chrome
|
||||
version prior to M62 (inclusive)
|
||||
-mt .................... use multi-threading if available
|
||||
|
||||
-version ............... print version number and exit
|
||||
-v ..................... verbose
|
||||
-quiet ................. don't print anything
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
With the libgif development files installed, gif2webp can be built using
|
||||
makefile.unix:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/gif2webp
|
||||
```
|
||||
|
||||
or using autoconf:
|
||||
|
||||
```shell
|
||||
$ ./configure --enable-everything
|
||||
$ make
|
||||
```
|
||||
|
||||
## Comparison of animated images
|
||||
|
||||
Test utility anim_diff under examples/ can be used to compare two animated
|
||||
images (each can be GIF or WebP).
|
||||
|
||||
Usage:
|
||||
|
||||
```shell
|
||||
anim_diff <image1> <image2> [options]
|
||||
```
|
||||
|
||||
Options:
|
||||
|
||||
```
|
||||
-dump_frames <folder> dump decoded frames in PAM format
|
||||
-min_psnr <float> ... minimum per-frame PSNR
|
||||
-raw_comparison ..... if this flag is not used, RGB is
|
||||
premultiplied before comparison
|
||||
-max_diff <int> ..... maximum allowed difference per channel
|
||||
between corresponding pixels in subsequent
|
||||
frames
|
||||
-h .................. this help
|
||||
-version ............ print version number and exit
|
||||
```
|
||||
|
||||
### Building
|
||||
|
||||
With the libgif development files installed, anim_diff can be built using
|
||||
makefile.unix:
|
||||
|
||||
```shell
|
||||
$ make -f makefile.unix examples/anim_diff
|
||||
```
|
||||
|
||||
or using autoconf:
|
||||
|
||||
```shell
|
||||
$ ./configure --enable-everything
|
||||
$ make
|
||||
```
|
||||
|
||||
## WebP Mux tool
|
||||
|
||||
The examples/ directory contains a tool (webpmux) for manipulating WebP files.
|
||||
The webpmux tool can be used to create an extended format WebP file and also to
|
||||
extract or strip relevant data from such a file.
|
||||
|
||||
A list of options is available using the -help command line flag:
|
||||
|
||||
```shell
|
||||
> webpmux -help
|
||||
Usage: webpmux -get GET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -set SET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -duration DURATION_OPTIONS [-duration ...]
|
||||
INPUT -o OUTPUT
|
||||
webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -frame FRAME_OPTIONS [-frame...] [-loop LOOP_COUNT]
|
||||
[-bgcolor BACKGROUND_COLOR] -o OUTPUT
|
||||
webpmux -info INPUT
|
||||
webpmux [-h|-help]
|
||||
webpmux -version
|
||||
webpmux argument_file_name
|
||||
|
||||
GET_OPTIONS:
|
||||
Extract relevant data:
|
||||
icc get ICC profile
|
||||
exif get EXIF metadata
|
||||
xmp get XMP metadata
|
||||
frame n get nth frame
|
||||
|
||||
SET_OPTIONS:
|
||||
Set color profile/metadata/parameters:
|
||||
loop LOOP_COUNT set the loop count
|
||||
bgcolor BACKGROUND_COLOR set the animation background color
|
||||
icc file.icc set ICC profile
|
||||
exif file.exif set EXIF metadata
|
||||
xmp file.xmp set XMP metadata
|
||||
where: 'file.icc' contains the ICC profile to be set,
|
||||
'file.exif' contains the EXIF metadata to be set
|
||||
'file.xmp' contains the XMP metadata to be set
|
||||
|
||||
DURATION_OPTIONS:
|
||||
Set duration of selected frames:
|
||||
duration set duration for all frames
|
||||
duration,frame set duration of a particular frame
|
||||
duration,start,end set duration of frames in the
|
||||
interval [start,end])
|
||||
where: 'duration' is the duration in milliseconds
|
||||
'start' is the start frame index
|
||||
'end' is the inclusive end frame index
|
||||
The special 'end' value '0' means: last frame.
|
||||
|
||||
STRIP_OPTIONS:
|
||||
Strip color profile/metadata:
|
||||
icc strip ICC profile
|
||||
exif strip EXIF metadata
|
||||
xmp strip XMP metadata
|
||||
|
||||
FRAME_OPTIONS(i):
|
||||
Create animation:
|
||||
file_i +di[+xi+yi[+mi[bi]]]
|
||||
where: 'file_i' is the i'th animation frame (WebP format),
|
||||
'di' is the pause duration before next frame,
|
||||
'xi','yi' specify the image offset for this frame,
|
||||
'mi' is the dispose method for this frame (0 or 1),
|
||||
'bi' is the blending method for this frame (+b or -b)
|
||||
|
||||
LOOP_COUNT:
|
||||
Number of times to repeat the animation.
|
||||
Valid range is 0 to 65535 [Default: 0 (infinite)].
|
||||
|
||||
BACKGROUND_COLOR:
|
||||
Background color of the canvas.
|
||||
A,R,G,B
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255 specifying
|
||||
the Alpha, Red, Green and Blue component values respectively
|
||||
[Default: 255,255,255,255]
|
||||
|
||||
INPUT & OUTPUT are in WebP format.
|
||||
|
||||
Note: The nature of EXIF, XMP and ICC data is not checked and is assumed to be
|
||||
valid.
|
||||
|
||||
Note: if a single file name is passed as the argument, the arguments will be
|
||||
tokenized from this file. The file name must not start with the character '-'.
|
||||
```
|
||||
@@ -0,0 +1,288 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:54 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>VWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>VWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#KEYBOARD SHORTCUTS">KEYBOARD SHORTCUTS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">vwebp −
|
||||
decompress a WebP file and display it in a window</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b>
|
||||
[<i>options</i>] <i>input_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>vwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b>
|
||||
decompresses a WebP file and displays it in a window using
|
||||
OpenGL.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−h</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print usage
|
||||
summary.</p> </td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print version number and
|
||||
exit.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−noicc</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="56%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Don’t use the
|
||||
ICC profile if present.</p></td>
|
||||
<td width="22%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofancy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the fancy
|
||||
YUV420 upscaler.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofilter</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable in-loop filtering.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−dither</b>
|
||||
<i>strength</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a dithering
|
||||
<b>strength</b> between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding
|
||||
banding artifacts. Default: 50.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%;"><b>−noalphadither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">By default, quantized
|
||||
transparency planes are dithered during decompression, to
|
||||
smooth the gradients. This flag will prevent this
|
||||
dithering.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−usebgcolor</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Fill transparent areas with the
|
||||
bitstream’s own background color instead of
|
||||
checkerboard only. Default is white for non-animated
|
||||
images.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use multi-threading
|
||||
for decoding, if possible.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−info</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Display image
|
||||
information on top of the decoded image.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "−", the data will be read
|
||||
from <i>stdin</i> instead of a file.</p>
|
||||
|
||||
<a name="KEYBOARD SHORTCUTS"></a>
|
||||
<h2>KEYBOARD SHORTCUTS</h2>
|
||||
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>’c’</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Toggle use of color
|
||||
profile.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>’b’</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Toggle display of
|
||||
background color.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>’i’</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Overlay file
|
||||
information.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>’d’</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Disable blending
|
||||
and disposal process, for debugging purposes.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>’q’ /
|
||||
’Q’ / ESC</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Quit.</p>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">vwebp
|
||||
picture.webp <br>
|
||||
vwebp picture.webp -mt -dither 0 <br>
|
||||
vwebp −− −−−picture.webp</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>vwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written for the Debian project (and may be used by
|
||||
others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>(1)
|
||||
<br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,103 @@
|
||||
VWEBP(1) VWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
vwebp - decompress a WebP file and display it in a window
|
||||
|
||||
SYNOPSIS
|
||||
vwebp [options] input_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the vwebp command.
|
||||
|
||||
vwebp decompresses a WebP file and displays it in a window using
|
||||
OpenGL.
|
||||
|
||||
OPTIONS
|
||||
-h Print usage summary.
|
||||
|
||||
-version
|
||||
Print version number and exit.
|
||||
|
||||
-noicc Don't use the ICC profile if present.
|
||||
|
||||
-nofancy
|
||||
Don't use the fancy YUV420 upscaler.
|
||||
|
||||
-nofilter
|
||||
Disable in-loop filtering.
|
||||
|
||||
-dither strength
|
||||
Specify a dithering strength between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding band-
|
||||
ing artifacts. Default: 50.
|
||||
|
||||
-noalphadither
|
||||
By default, quantized transparency planes are dithered during
|
||||
decompression, to smooth the gradients. This flag will prevent
|
||||
this dithering.
|
||||
|
||||
-usebgcolor
|
||||
Fill transparent areas with the bitstream's own background color
|
||||
instead of checkerboard only. Default is white for non-animated
|
||||
images.
|
||||
|
||||
-mt Use multi-threading for decoding, if possible.
|
||||
|
||||
-info Display image information on top of the decoded image.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from stdin instead
|
||||
of a file.
|
||||
|
||||
|
||||
|
||||
KEYBOARD SHORTCUTS
|
||||
|
||||
'c' Toggle use of color profile.
|
||||
|
||||
'b' Toggle display of background color.
|
||||
|
||||
'i' Overlay file information.
|
||||
|
||||
'd' Disable blending and disposal process, for debugging purposes.
|
||||
|
||||
'q' / 'Q' / ESC
|
||||
Quit.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
vwebp picture.webp
|
||||
vwebp picture.webp -mt -dither 0
|
||||
vwebp -- ---picture.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
vwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written for the Debian project (and may be used by
|
||||
others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
dwebp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 VWEBP(1)
|
||||
@@ -0,0 +1,184 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:55 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>WEBPINFO</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>WEBPINFO</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#INPUT">INPUT</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpinfo
|
||||
− print out the chunk level structure of WebP files
|
||||
along with basic integrity checks.</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
<i>OPTIONS INPUT</i> <b><br>
|
||||
webpinfo
|
||||
[−h|−help|−H|−longhelp]</b></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>webpinfo</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
can be used to print out the chunk level structure and
|
||||
bitstream header information of WebP files. It can also
|
||||
check if the files are of valid WebP format.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="58%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not show chunk
|
||||
parsing information.</p></td>
|
||||
<td width="20%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−diag</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="58%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Show parsing error
|
||||
diagnosis.</p> </td>
|
||||
<td width="20%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−summary</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Show chunk stats summary.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%;"><b>−bitstream_info</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Parse bitstream header.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−H,
|
||||
−longhelp</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Detailed usage
|
||||
instructions.</p>
|
||||
|
||||
<a name="INPUT"></a>
|
||||
<h2>INPUT</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Input files in
|
||||
WebP format. Input files must come last, following options
|
||||
(if any). There can be multiple input files.</p>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpinfo
|
||||
−h <br>
|
||||
webpinfo −diag −summary input_file.webp <br>
|
||||
webpinfo −bitstream_info input_file_1.webp
|
||||
input_file_2.webp <br>
|
||||
webpinfo *.webp</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpinfo</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Hui Su <huisu@google.com>, for the
|
||||
Debian project (and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>(1)
|
||||
<br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,78 @@
|
||||
WEBPINFO(1) WEBPINFO(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
webpinfo - print out the chunk level structure of WebP files along with
|
||||
basic integrity checks.
|
||||
|
||||
SYNOPSIS
|
||||
webpinfo OPTIONS INPUT
|
||||
webpinfo [-h|-help|-H|-longhelp]
|
||||
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the webpinfo command.
|
||||
|
||||
webpinfo can be used to print out the chunk level structure and bit-
|
||||
stream header information of WebP files. It can also check if the files
|
||||
are of valid WebP format.
|
||||
|
||||
|
||||
OPTIONS
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-quiet Do not show chunk parsing information.
|
||||
|
||||
-diag Show parsing error diagnosis.
|
||||
|
||||
-summary
|
||||
Show chunk stats summary.
|
||||
|
||||
-bitstream_info
|
||||
Parse bitstream header.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-H, -longhelp
|
||||
Detailed usage instructions.
|
||||
|
||||
|
||||
INPUT
|
||||
Input files in WebP format. Input files must come last, following
|
||||
options (if any). There can be multiple input files.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
webpinfo -h
|
||||
webpinfo -diag -summary input_file.webp
|
||||
webpinfo -bitstream_info input_file_1.webp input_file_2.webp
|
||||
webpinfo *.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
webpinfo is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Hui Su <huisu@google.com>, for the
|
||||
Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 WEBPINFO(1)
|
||||
@@ -0,0 +1,436 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:54 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>WEBPMUX</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>WEBPMUX</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">webpmux −
|
||||
create animated WebP files from non−animated WebP
|
||||
images, extract frames from animated WebP images, and manage
|
||||
XMP/EXIF metadata and ICC profile.</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux
|
||||
−get</b> <i>GET_OPTIONS INPUT</i> <b>−o</b>
|
||||
<i>OUTPUT</i> <b><br>
|
||||
webpmux −set</b> <i>SET_OPTIONS INPUT</i>
|
||||
<b>−o</b> <i>OUTPUT</i> <b><br>
|
||||
webpmux −strip</b> <i>STRIP_OPTIONS INPUT</i>
|
||||
<b>−o</b> <i>OUTPUT</i> <b><br>
|
||||
webpmux −frame</b> <i>FRAME_OPTIONS</i> <b>[
|
||||
−frame ... ] [ −loop</b> <i>LOOP_COUNT</i>
|
||||
<b>]</b></p>
|
||||
|
||||
<p style="margin-left:23%;"><b>[ −bgcolor</b>
|
||||
<i>BACKGROUND_COLOR</i> <b>] −o</b> <i>OUTPUT</i></p>
|
||||
|
||||
<p style="margin-left:11%;"><b>webpmux −duration</b>
|
||||
<i>DURATION OPTIONS</i> <b>[ −duration ... ]</b>
|
||||
<i>INPUT</i> <b>−o</b> <i>OUTPUT</i> <b><br>
|
||||
webpmux −info</b> <i>INPUT</i> <b><br>
|
||||
webpmux [−h|−help] <br>
|
||||
webpmux −version <br>
|
||||
webpmux argument_file_name</b></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>webpmux</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>
|
||||
can be used to create/extract from animated WebP files, as
|
||||
well as to add/extract/strip XMP/EXIF metadata and ICC
|
||||
profile. If a single file name (not starting with the
|
||||
character ’−’) is supplied as the
|
||||
argument, the command line arguments are actually tokenized
|
||||
from this file. This allows for easy scripting or using a
|
||||
large number of arguments.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>GET_OPTIONS
|
||||
(−get):</b></p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p valign="top"><b>icc</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p valign="top">Get ICC profile.</p></td>
|
||||
<td width="51%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>exif</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Get EXIF
|
||||
metadata.</p> </td>
|
||||
<td width="51%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>xmp</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="27%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Get XMP
|
||||
metadata.</p> </td>
|
||||
<td width="51%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>frame</b> <i>n</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Get nth frame from an animated
|
||||
image. (n = 0 has a special meaning: last frame).</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>SET_OPTIONS
|
||||
(−set) <br>
|
||||
loop</b> <i>loop_count</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set loop count on an animated
|
||||
file.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’loop_count’ must be in range [0, 65535].
|
||||
<b><br>
|
||||
bgcolor</b> <i>A,R,G,B</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set the background color of the
|
||||
canvas on an animated file.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">where:
|
||||
’A’, ’R’, ’G’ and
|
||||
’B’ are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values
|
||||
respectively. <b><br>
|
||||
icc</b> <i>file.icc</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set ICC profile.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.icc’ contains the ICC profile to be set.
|
||||
<b><br>
|
||||
exif</b> <i>file.exif</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set EXIF metadata.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.exif’ contains the EXIF metadata to be
|
||||
set. <b><br>
|
||||
xmp</b> <i>file.xmp</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set XMP metadata.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Where:
|
||||
’file.xmp’ contains the XMP metadata to be
|
||||
set.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>STRIP_OPTIONS
|
||||
(−strip)</b></p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p valign="top"><b>icc</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p valign="top">Strip ICC profile.</p></td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>exif</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Strip EXIF
|
||||
metadata.</p> </td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="6%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>xmp</b></p></td>
|
||||
<td width="5%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Strip XMP
|
||||
metadata.</p> </td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>DURATION_OPTIONS
|
||||
(−duration)</b> <br>
|
||||
Amend the duration of a specific interval of frames. This
|
||||
option is only effective on animated WebP and has no effect
|
||||
on a single-frame file. <i><br>
|
||||
duration[,start[,end]]</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Where: <b><br>
|
||||
duration</b> is the duration for the interval in
|
||||
milliseconds (mandatory). Must be non-negative. <b><br>
|
||||
start</b> is the starting frame index of the interval
|
||||
(optional). <b><br>
|
||||
end</b> is the ending frame index (inclusive) of the
|
||||
interval (optional).</p>
|
||||
|
||||
<p style="margin-left:11%;">The three typical usages of
|
||||
this option are:</p>
|
||||
|
||||
<p style="margin-left:22%;"><b>-duration d</b> <br>
|
||||
set the duration to ’d’ for the whole animation.
|
||||
<b><br>
|
||||
-duration d,f</b> <br>
|
||||
set the duration of frame ’f’ to
|
||||
’d’. <b><br>
|
||||
-duration d,start,end</b> <br>
|
||||
set the duration to ’d’ for the whole
|
||||
[start,end] interval.</p>
|
||||
|
||||
<p style="margin-left:22%; margin-top: 1em">Note that the
|
||||
frames outside of the [start, end] interval will <br>
|
||||
remain untouched. <br>
|
||||
The ’end’ value ’0’ has the special
|
||||
meaning ’last frame of the animation’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><i>Reminder:</i></p>
|
||||
|
||||
<p style="margin-left:22%;">frame indexing starts at
|
||||
’1’.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>FRAME_OPTIONS
|
||||
(−frame)</b> <br>
|
||||
Create an animated WebP file from multiple
|
||||
(non−animated) WebP images. <i><br>
|
||||
file_i +di[+xi+yi[+mi[bi]]]</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Where: ’file_i’ is
|
||||
the i’th frame (WebP format),
|
||||
’xi’,’yi’ specify the image offset
|
||||
for this frame, ’di’ is the pause duration
|
||||
before next frame, ’mi’ is the dispose method
|
||||
for this frame (0 for NONE or 1 for BACKGROUND) and
|
||||
’bi’ is the blending method for this frame (+b
|
||||
for BLEND or −b for NO_BLEND). Argument
|
||||
’bi’ can be omitted and will default to +b
|
||||
(BLEND). Also, ’mi’ can be omitted if
|
||||
’bi’ is omitted and will default to 0 (NONE).
|
||||
Finally, if ’mi’ and ’bi’ are
|
||||
omitted then ’xi’ and ’yi’ can be
|
||||
omitted and will default to +0+0.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−loop</b> <i>n</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Loop the frames n number of
|
||||
times. 0 indicates the frames should loop forever. Valid
|
||||
range is 0 to 65535 [Default: 0 (infinite)].</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−bgcolor</b>
|
||||
<i>A,R,G,B</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Background color of the canvas.
|
||||
<br>
|
||||
where: ’A’, ’R’, ’G’ and
|
||||
’B’ are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values
|
||||
respectively [Default: 255,255,255,255].</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>INPUT</b>
|
||||
<br>
|
||||
Input file in WebP format.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>OUTPUT
|
||||
(−o)</b> <br>
|
||||
Output file in WebP format.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>Note:</b>
|
||||
<br>
|
||||
The nature of EXIF, XMP and ICC data is not checked and is
|
||||
assumed to <br>
|
||||
be valid.</p>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add ICC
|
||||
profile: <br>
|
||||
webpmux −set icc image_profile.icc in.webp −o
|
||||
icc_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract ICC
|
||||
profile: <br>
|
||||
webpmux −get icc icc_container.webp −o
|
||||
image_profile.icc</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip ICC
|
||||
profile: <br>
|
||||
webpmux −strip icc icc_container.webp −o
|
||||
without_icc.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add XMP
|
||||
metadata: <br>
|
||||
webpmux −set xmp image_metadata.xmp in.webp −o
|
||||
xmp_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract XMP
|
||||
metadata: <br>
|
||||
webpmux −get xmp xmp_container.webp −o
|
||||
image_metadata.xmp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip XMP
|
||||
metadata: <br>
|
||||
webpmux −strip xmp xmp_container.webp −o
|
||||
without_xmp.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Add EXIF
|
||||
metadata: <br>
|
||||
webpmux −set exif image_metadata.exif in.webp −o
|
||||
exif_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Extract EXIF
|
||||
metadata: <br>
|
||||
webpmux −get exif exif_container.webp −o
|
||||
image_metadata.exif</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Strip EXIF
|
||||
metadata: <br>
|
||||
webpmux −strip exif exif_container.webp −o
|
||||
without_exif.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Create an
|
||||
animated WebP file from 3 (non−animated) WebP images:
|
||||
<br>
|
||||
webpmux −frame 1.webp +100 −frame 2.webp
|
||||
+100+50+50</p>
|
||||
|
||||
<p style="margin-left:23%;">−frame 3.webp
|
||||
+100+50+50+1+b −loop 10 −bgcolor 255,255,255,255
|
||||
<br>
|
||||
−o anim_container.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Get the 2nd
|
||||
frame from an animated WebP file: <br>
|
||||
webpmux −get frame 2 anim_container.webp −o
|
||||
frame_2.webp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Using
|
||||
−get/−set/−strip with input file name
|
||||
starting with ’−’: <br>
|
||||
webpmux −set icc image_profile.icc −o
|
||||
icc_container.webp −−
|
||||
−−−in.webp <br>
|
||||
webpmux −get icc −o image_profile.icc
|
||||
−− −−−icc_container.webp <br>
|
||||
webpmux −strip icc −o without_icc.webp
|
||||
−− −−−icc_container.webp</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>webpmux</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Vikas Arora
|
||||
<vikaas.arora@gmail.com>, for the Debian project (and
|
||||
may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>dwebp</b>(1), <b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,216 @@
|
||||
WEBPMUX(1) WEBPMUX(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
webpmux - create animated WebP files from non-animated WebP images,
|
||||
extract frames from animated WebP images, and manage XMP/EXIF metadata
|
||||
and ICC profile.
|
||||
|
||||
SYNOPSIS
|
||||
webpmux -get GET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -set SET_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
|
||||
webpmux -frame FRAME_OPTIONS [ -frame ... ] [ -loop LOOP_COUNT ]
|
||||
[ -bgcolor BACKGROUND_COLOR ] -o OUTPUT
|
||||
webpmux -duration DURATION OPTIONS [ -duration ... ] INPUT -o OUTPUT
|
||||
webpmux -info INPUT
|
||||
webpmux [-h|-help]
|
||||
webpmux -version
|
||||
webpmux argument_file_name
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the webpmux command.
|
||||
|
||||
webpmux can be used to create/extract from animated WebP files, as well
|
||||
as to add/extract/strip XMP/EXIF metadata and ICC profile. If a single
|
||||
file name (not starting with the character '-') is supplied as the
|
||||
argument, the command line arguments are actually tokenized from this
|
||||
file. This allows for easy scripting or using a large number of argu-
|
||||
ments.
|
||||
|
||||
OPTIONS
|
||||
GET_OPTIONS (-get):
|
||||
icc Get ICC profile.
|
||||
|
||||
exif Get EXIF metadata.
|
||||
|
||||
xmp Get XMP metadata.
|
||||
|
||||
frame n
|
||||
Get nth frame from an animated image. (n = 0 has a special mean-
|
||||
ing: last frame).
|
||||
|
||||
|
||||
SET_OPTIONS (-set)
|
||||
loop loop_count
|
||||
Set loop count on an animated file.
|
||||
|
||||
Where: 'loop_count' must be in range [0, 65535].
|
||||
|
||||
bgcolor A,R,G,B
|
||||
Set the background color of the canvas on an animated file.
|
||||
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255 speci-
|
||||
fying the Alpha, Red, Green and Blue component values respectively.
|
||||
|
||||
icc file.icc
|
||||
Set ICC profile.
|
||||
|
||||
Where: 'file.icc' contains the ICC profile to be set.
|
||||
|
||||
exif file.exif
|
||||
Set EXIF metadata.
|
||||
|
||||
Where: 'file.exif' contains the EXIF metadata to be set.
|
||||
|
||||
xmp file.xmp
|
||||
Set XMP metadata.
|
||||
|
||||
Where: 'file.xmp' contains the XMP metadata to be set.
|
||||
|
||||
|
||||
STRIP_OPTIONS (-strip)
|
||||
icc Strip ICC profile.
|
||||
|
||||
exif Strip EXIF metadata.
|
||||
|
||||
xmp Strip XMP metadata.
|
||||
|
||||
|
||||
DURATION_OPTIONS (-duration)
|
||||
Amend the duration of a specific interval of frames. This option is
|
||||
only effective on animated WebP and has no effect on a single-frame
|
||||
file.
|
||||
|
||||
duration[,start[,end]]
|
||||
Where:
|
||||
duration is the duration for the interval in milliseconds
|
||||
(mandatory). Must be non-negative.
|
||||
start is the starting frame index of the interval (optional).
|
||||
end is the ending frame index (inclusive) of the interval
|
||||
(optional).
|
||||
|
||||
The three typical usages of this option are:
|
||||
-duration d
|
||||
set the duration to 'd' for the whole animation.
|
||||
-duration d,f
|
||||
set the duration of frame 'f' to 'd'.
|
||||
-duration d,start,end
|
||||
set the duration to 'd' for the whole [start,end] interval.
|
||||
|
||||
|
||||
Note that the frames outside of the [start, end] interval will
|
||||
remain untouched.
|
||||
The 'end' value '0' has the special meaning 'last frame of the
|
||||
animation'.
|
||||
|
||||
Reminder:
|
||||
frame indexing starts at '1'.
|
||||
|
||||
|
||||
FRAME_OPTIONS (-frame)
|
||||
Create an animated WebP file from multiple (non-animated) WebP images.
|
||||
|
||||
file_i +di[+xi+yi[+mi[bi]]]
|
||||
Where: 'file_i' is the i'th frame (WebP format), 'xi','yi' spec-
|
||||
ify the image offset for this frame, 'di' is the pause duration
|
||||
before next frame, 'mi' is the dispose method for this frame (0
|
||||
for NONE or 1 for BACKGROUND) and 'bi' is the blending method
|
||||
for this frame (+b for BLEND or -b for NO_BLEND). Argument 'bi'
|
||||
can be omitted and will default to +b (BLEND). Also, 'mi' can
|
||||
be omitted if 'bi' is omitted and will default to 0 (NONE).
|
||||
Finally, if 'mi' and 'bi' are omitted then 'xi' and 'yi' can be
|
||||
omitted and will default to +0+0.
|
||||
|
||||
-loop n
|
||||
Loop the frames n number of times. 0 indicates the frames should
|
||||
loop forever. Valid range is 0 to 65535 [Default: 0 (infi-
|
||||
nite)].
|
||||
|
||||
-bgcolor A,R,G,B
|
||||
Background color of the canvas.
|
||||
where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255
|
||||
specifying the Alpha, Red, Green and Blue component values
|
||||
respectively [Default: 255,255,255,255].
|
||||
|
||||
|
||||
INPUT
|
||||
Input file in WebP format.
|
||||
|
||||
|
||||
OUTPUT (-o)
|
||||
Output file in WebP format.
|
||||
|
||||
|
||||
Note:
|
||||
The nature of EXIF, XMP and ICC data is not checked and is assumed to
|
||||
be valid.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
Add ICC profile:
|
||||
webpmux -set icc image_profile.icc in.webp -o icc_container.webp
|
||||
|
||||
Extract ICC profile:
|
||||
webpmux -get icc icc_container.webp -o image_profile.icc
|
||||
|
||||
Strip ICC profile:
|
||||
webpmux -strip icc icc_container.webp -o without_icc.webp
|
||||
|
||||
Add XMP metadata:
|
||||
webpmux -set xmp image_metadata.xmp in.webp -o xmp_container.webp
|
||||
|
||||
Extract XMP metadata:
|
||||
webpmux -get xmp xmp_container.webp -o image_metadata.xmp
|
||||
|
||||
Strip XMP metadata:
|
||||
webpmux -strip xmp xmp_container.webp -o without_xmp.webp
|
||||
|
||||
Add EXIF metadata:
|
||||
webpmux -set exif image_metadata.exif in.webp -o exif_container.webp
|
||||
|
||||
Extract EXIF metadata:
|
||||
webpmux -get exif exif_container.webp -o image_metadata.exif
|
||||
|
||||
Strip EXIF metadata:
|
||||
webpmux -strip exif exif_container.webp -o without_exif.webp
|
||||
|
||||
Create an animated WebP file from 3 (non-animated) WebP images:
|
||||
webpmux -frame 1.webp +100 -frame 2.webp +100+50+50
|
||||
-frame 3.webp +100+50+50+1+b -loop 10 -bgcolor 255,255,255,255
|
||||
-o anim_container.webp
|
||||
|
||||
Get the 2nd frame from an animated WebP file:
|
||||
webpmux -get frame 2 anim_container.webp -o frame_2.webp
|
||||
|
||||
Using -get/-set/-strip with input file name starting with '-':
|
||||
webpmux -set icc image_profile.icc -o icc_container.webp -- ---in.webp
|
||||
webpmux -get icc -o image_profile.icc -- ---icc_container.webp
|
||||
webpmux -strip icc -o without_icc.webp -- ---icc_container.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
webpmux is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Vikas Arora <vikaas.arora@gmail.com>,
|
||||
for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), dwebp(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 WEBPMUX(1)
|
||||
@@ -0,0 +1,503 @@
|
||||
// Copyright 2010 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Main decoding functions for WebP images.
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_DECODE_H_
|
||||
#define WEBP_WEBP_DECODE_H_
|
||||
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_DECODER_ABI_VERSION 0x0209 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum VP8StatusCode VP8StatusCode;
|
||||
// typedef enum WEBP_CSP_MODE WEBP_CSP_MODE;
|
||||
typedef struct WebPRGBABuffer WebPRGBABuffer;
|
||||
typedef struct WebPYUVABuffer WebPYUVABuffer;
|
||||
typedef struct WebPDecBuffer WebPDecBuffer;
|
||||
typedef struct WebPIDecoder WebPIDecoder;
|
||||
typedef struct WebPBitstreamFeatures WebPBitstreamFeatures;
|
||||
typedef struct WebPDecoderOptions WebPDecoderOptions;
|
||||
typedef struct WebPDecoderConfig WebPDecoderConfig;
|
||||
|
||||
// Return the decoder's version number, packed in hexadecimal using 8bits for
|
||||
// each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetDecoderVersion(void);
|
||||
|
||||
// Retrieve basic header information: width, height.
|
||||
// This function will also validate the header, returning true on success,
|
||||
// false otherwise. '*width' and '*height' are only valid on successful return.
|
||||
// Pointers 'width' and 'height' can be passed NULL if deemed irrelevant.
|
||||
// Note: The following chunk sequences (before the raw VP8/VP8L data) are
|
||||
// considered valid by this function:
|
||||
// RIFF + VP8(L)
|
||||
// RIFF + VP8X + (optional chunks) + VP8(L)
|
||||
// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
WEBP_EXTERN int WebPGetInfo(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Decodes WebP images pointed to by 'data' and returns RGBA samples, along
|
||||
// with the dimensions in *width and *height. The ordering of samples in
|
||||
// memory is R, G, B, A, R, G, B, A... in scan order (endian-independent).
|
||||
// The returned pointer should be deleted calling WebPFree().
|
||||
// Returns NULL in case of error.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBA(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning A, R, G, B, A, R, G, B... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeARGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning B, G, R, A, B, G, R, A... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRA(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGBA, but returning R, G, B, R, G, B... ordered data.
|
||||
// If the bitstream contains transparency, it is ignored.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
// Same as WebPDecodeRGB, but returning B, G, R, B, G, R... ordered data.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGR(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
|
||||
|
||||
// Decode WebP images pointed to by 'data' to Y'UV format(*). The pointer
|
||||
// returned is the Y samples buffer. Upon return, *u and *v will point to
|
||||
// the U and V chroma data. These U and V buffers need NOT be passed to
|
||||
// WebPFree(), unlike the returned Y luma one. The dimension of the U and V
|
||||
// planes are both (*width + 1) / 2 and (*height + 1)/ 2.
|
||||
// Upon return, the Y buffer has a stride returned as '*stride', while U and V
|
||||
// have a common stride returned as '*uv_stride'.
|
||||
// Return NULL in case of error.
|
||||
// (*) Also named Y'CbCr. See: https://en.wikipedia.org/wiki/YCbCr
|
||||
WEBP_EXTERN uint8_t* WebPDecodeYUV(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height,
|
||||
uint8_t** u, uint8_t** v,
|
||||
int* stride, int* uv_stride);
|
||||
|
||||
// These five functions are variants of the above ones, that decode the image
|
||||
// directly into a pre-allocated buffer 'output_buffer'. The maximum storage
|
||||
// available in this buffer is indicated by 'output_buffer_size'. If this
|
||||
// storage is not sufficient (or an error occurred), NULL is returned.
|
||||
// Otherwise, output_buffer is returned, for convenience.
|
||||
// The parameter 'output_stride' specifies the distance (in bytes)
|
||||
// between scanlines. Hence, output_buffer_size is expected to be at least
|
||||
// output_stride x picture-height.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBAInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeARGBInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRAInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// RGB and BGR variants. Here too the transparency information, if present,
|
||||
// will be dropped and ignored.
|
||||
WEBP_EXTERN uint8_t* WebPDecodeRGBInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
WEBP_EXTERN uint8_t* WebPDecodeBGRInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// WebPDecodeYUVInto() is a variant of WebPDecodeYUV() that operates directly
|
||||
// into pre-allocated luma/chroma plane buffers. This function requires the
|
||||
// strides to be passed: one for the luma plane and one for each of the
|
||||
// chroma ones. The size of each plane buffer is passed as 'luma_size',
|
||||
// 'u_size' and 'v_size' respectively.
|
||||
// Pointer to the luma plane ('*luma') is returned or NULL if an error occurred
|
||||
// during decoding (or because some buffers were found to be too small).
|
||||
WEBP_EXTERN uint8_t* WebPDecodeYUVInto(
|
||||
const uint8_t* data, size_t data_size,
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Output colorspaces and buffer
|
||||
|
||||
// Colorspaces
|
||||
// Note: the naming describes the byte-ordering of packed samples in memory.
|
||||
// For instance, MODE_BGRA relates to samples ordered as B,G,R,A,B,G,R,A,...
|
||||
// Non-capital names (e.g.:MODE_Argb) relates to pre-multiplied RGB channels.
|
||||
// RGBA-4444 and RGB-565 colorspaces are represented by following byte-order:
|
||||
// RGBA-4444: [r3 r2 r1 r0 g3 g2 g1 g0], [b3 b2 b1 b0 a3 a2 a1 a0], ...
|
||||
// RGB-565: [r4 r3 r2 r1 r0 g5 g4 g3], [g2 g1 g0 b4 b3 b2 b1 b0], ...
|
||||
// In the case WEBP_SWAP_16BITS_CSP is defined, the bytes are swapped for
|
||||
// these two modes:
|
||||
// RGBA-4444: [b3 b2 b1 b0 a3 a2 a1 a0], [r3 r2 r1 r0 g3 g2 g1 g0], ...
|
||||
// RGB-565: [g2 g1 g0 b4 b3 b2 b1 b0], [r4 r3 r2 r1 r0 g5 g4 g3], ...
|
||||
|
||||
typedef enum WEBP_CSP_MODE {
|
||||
MODE_RGB = 0, MODE_RGBA = 1,
|
||||
MODE_BGR = 2, MODE_BGRA = 3,
|
||||
MODE_ARGB = 4, MODE_RGBA_4444 = 5,
|
||||
MODE_RGB_565 = 6,
|
||||
// RGB-premultiplied transparent modes (alpha value is preserved)
|
||||
MODE_rgbA = 7,
|
||||
MODE_bgrA = 8,
|
||||
MODE_Argb = 9,
|
||||
MODE_rgbA_4444 = 10,
|
||||
// YUV modes must come after RGB ones.
|
||||
MODE_YUV = 11, MODE_YUVA = 12, // yuv 4:2:0
|
||||
MODE_LAST = 13
|
||||
} WEBP_CSP_MODE;
|
||||
|
||||
// Some useful macros:
|
||||
static WEBP_INLINE int WebPIsPremultipliedMode(WEBP_CSP_MODE mode) {
|
||||
return (mode == MODE_rgbA || mode == MODE_bgrA || mode == MODE_Argb ||
|
||||
mode == MODE_rgbA_4444);
|
||||
}
|
||||
|
||||
static WEBP_INLINE int WebPIsAlphaMode(WEBP_CSP_MODE mode) {
|
||||
return (mode == MODE_RGBA || mode == MODE_BGRA || mode == MODE_ARGB ||
|
||||
mode == MODE_RGBA_4444 || mode == MODE_YUVA ||
|
||||
WebPIsPremultipliedMode(mode));
|
||||
}
|
||||
|
||||
static WEBP_INLINE int WebPIsRGBMode(WEBP_CSP_MODE mode) {
|
||||
return (mode < MODE_YUV);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPDecBuffer: Generic structure for describing the output sample buffer.
|
||||
|
||||
struct WebPRGBABuffer { // view as RGBA
|
||||
uint8_t* rgba; // pointer to RGBA samples
|
||||
int stride; // stride in bytes from one scanline to the next.
|
||||
size_t size; // total size of the *rgba buffer.
|
||||
};
|
||||
|
||||
struct WebPYUVABuffer { // view as YUVA
|
||||
uint8_t* y, *u, *v, *a; // pointer to luma, chroma U/V, alpha samples
|
||||
int y_stride; // luma stride
|
||||
int u_stride, v_stride; // chroma strides
|
||||
int a_stride; // alpha stride
|
||||
size_t y_size; // luma plane size
|
||||
size_t u_size, v_size; // chroma planes size
|
||||
size_t a_size; // alpha-plane size
|
||||
};
|
||||
|
||||
// Output buffer
|
||||
struct WebPDecBuffer {
|
||||
WEBP_CSP_MODE colorspace; // Colorspace.
|
||||
int width, height; // Dimensions.
|
||||
int is_external_memory; // If non-zero, 'internal_memory' pointer is not
|
||||
// used. If value is '2' or more, the external
|
||||
// memory is considered 'slow' and multiple
|
||||
// read/write will be avoided.
|
||||
union {
|
||||
WebPRGBABuffer RGBA;
|
||||
WebPYUVABuffer YUVA;
|
||||
} u; // Nameless union of buffer parameters.
|
||||
uint32_t pad[4]; // padding for later use
|
||||
|
||||
uint8_t* private_memory; // Internally allocated memory (only when
|
||||
// is_external_memory is 0). Should not be used
|
||||
// externally, but accessed via the buffer union.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPInitDecBufferInternal(WebPDecBuffer*, int);
|
||||
|
||||
// Initialize the structure as empty. Must be called before any other use.
|
||||
// Returns false in case of version mismatch
|
||||
static WEBP_INLINE int WebPInitDecBuffer(WebPDecBuffer* buffer) {
|
||||
return WebPInitDecBufferInternal(buffer, WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Free any memory associated with the buffer. Must always be called last.
|
||||
// Note: doesn't free the 'buffer' structure itself.
|
||||
WEBP_EXTERN void WebPFreeDecBuffer(WebPDecBuffer* buffer);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Enumeration of the status codes
|
||||
|
||||
typedef enum VP8StatusCode {
|
||||
VP8_STATUS_OK = 0,
|
||||
VP8_STATUS_OUT_OF_MEMORY,
|
||||
VP8_STATUS_INVALID_PARAM,
|
||||
VP8_STATUS_BITSTREAM_ERROR,
|
||||
VP8_STATUS_UNSUPPORTED_FEATURE,
|
||||
VP8_STATUS_SUSPENDED,
|
||||
VP8_STATUS_USER_ABORT,
|
||||
VP8_STATUS_NOT_ENOUGH_DATA
|
||||
} VP8StatusCode;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Incremental decoding
|
||||
//
|
||||
// This API allows streamlined decoding of partial data.
|
||||
// Picture can be incrementally decoded as data become available thanks to the
|
||||
// WebPIDecoder object. This object can be left in a SUSPENDED state if the
|
||||
// picture is only partially decoded, pending additional input.
|
||||
// Code example:
|
||||
//
|
||||
// WebPInitDecBuffer(&output_buffer);
|
||||
// output_buffer.colorspace = mode;
|
||||
// ...
|
||||
// WebPIDecoder* idec = WebPINewDecoder(&output_buffer);
|
||||
// while (additional_data_is_available) {
|
||||
// // ... (get additional data in some new_data[] buffer)
|
||||
// status = WebPIAppend(idec, new_data, new_data_size);
|
||||
// if (status != VP8_STATUS_OK && status != VP8_STATUS_SUSPENDED) {
|
||||
// break; // an error occurred.
|
||||
// }
|
||||
//
|
||||
// // The above call decodes the current available buffer.
|
||||
// // Part of the image can now be refreshed by calling
|
||||
// // WebPIDecGetRGB()/WebPIDecGetYUVA() etc.
|
||||
// }
|
||||
// WebPIDelete(idec);
|
||||
|
||||
// Creates a new incremental decoder with the supplied buffer parameter.
|
||||
// This output_buffer can be passed NULL, in which case a default output buffer
|
||||
// is used (with MODE_RGB). Otherwise, an internal reference to 'output_buffer'
|
||||
// is kept, which means that the lifespan of 'output_buffer' must be larger than
|
||||
// that of the returned WebPIDecoder object.
|
||||
// The supplied 'output_buffer' content MUST NOT be changed between calls to
|
||||
// WebPIAppend() or WebPIUpdate() unless 'output_buffer.is_external_memory' is
|
||||
// not set to 0. In such a case, it is allowed to modify the pointers, size and
|
||||
// stride of output_buffer.u.RGBA or output_buffer.u.YUVA, provided they remain
|
||||
// within valid bounds.
|
||||
// All other fields of WebPDecBuffer MUST remain constant between calls.
|
||||
// Returns NULL if the allocation failed.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewDecoder(WebPDecBuffer* output_buffer);
|
||||
|
||||
// This function allocates and initializes an incremental-decoder object, which
|
||||
// will output the RGB/A samples specified by 'csp' into a preallocated
|
||||
// buffer 'output_buffer'. The size of this buffer is at least
|
||||
// 'output_buffer_size' and the stride (distance in bytes between two scanlines)
|
||||
// is specified by 'output_stride'.
|
||||
// Additionally, output_buffer can be passed NULL in which case the output
|
||||
// buffer will be allocated automatically when the decoding starts. The
|
||||
// colorspace 'csp' is taken into account for allocating this buffer. All other
|
||||
// parameters are ignored.
|
||||
// Returns NULL if the allocation failed, or if some parameters are invalid.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewRGB(
|
||||
WEBP_CSP_MODE csp,
|
||||
uint8_t* output_buffer, size_t output_buffer_size, int output_stride);
|
||||
|
||||
// This function allocates and initializes an incremental-decoder object, which
|
||||
// will output the raw luma/chroma samples into a preallocated planes if
|
||||
// supplied. The luma plane is specified by its pointer 'luma', its size
|
||||
// 'luma_size' and its stride 'luma_stride'. Similarly, the chroma-u plane
|
||||
// is specified by the 'u', 'u_size' and 'u_stride' parameters, and the chroma-v
|
||||
// plane by 'v' and 'v_size'. And same for the alpha-plane. The 'a' pointer
|
||||
// can be pass NULL in case one is not interested in the transparency plane.
|
||||
// Conversely, 'luma' can be passed NULL if no preallocated planes are supplied.
|
||||
// In this case, the output buffer will be automatically allocated (using
|
||||
// MODE_YUVA) when decoding starts. All parameters are then ignored.
|
||||
// Returns NULL if the allocation failed or if a parameter is invalid.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewYUVA(
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride,
|
||||
uint8_t* a, size_t a_size, int a_stride);
|
||||
|
||||
// Deprecated version of the above, without the alpha plane.
|
||||
// Kept for backward compatibility.
|
||||
WEBP_EXTERN WebPIDecoder* WebPINewYUV(
|
||||
uint8_t* luma, size_t luma_size, int luma_stride,
|
||||
uint8_t* u, size_t u_size, int u_stride,
|
||||
uint8_t* v, size_t v_size, int v_stride);
|
||||
|
||||
// Deletes the WebPIDecoder object and associated memory. Must always be called
|
||||
// if WebPINewDecoder, WebPINewRGB or WebPINewYUV succeeded.
|
||||
WEBP_EXTERN void WebPIDelete(WebPIDecoder* idec);
|
||||
|
||||
// Copies and decodes the next available data. Returns VP8_STATUS_OK when
|
||||
// the image is successfully decoded. Returns VP8_STATUS_SUSPENDED when more
|
||||
// data is expected. Returns error in other cases.
|
||||
WEBP_EXTERN VP8StatusCode WebPIAppend(
|
||||
WebPIDecoder* idec, const uint8_t* data, size_t data_size);
|
||||
|
||||
// A variant of the above function to be used when data buffer contains
|
||||
// partial data from the beginning. In this case data buffer is not copied
|
||||
// to the internal memory.
|
||||
// Note that the value of the 'data' pointer can change between calls to
|
||||
// WebPIUpdate, for instance when the data buffer is resized to fit larger data.
|
||||
WEBP_EXTERN VP8StatusCode WebPIUpdate(
|
||||
WebPIDecoder* idec, const uint8_t* data, size_t data_size);
|
||||
|
||||
// Returns the RGB/A image decoded so far. Returns NULL if output params
|
||||
// are not initialized yet. The RGB/A output type corresponds to the colorspace
|
||||
// specified during call to WebPINewDecoder() or WebPINewRGB().
|
||||
// *last_y is the index of last decoded row in raster scan order. Some pointers
|
||||
// (*last_y, *width etc.) can be NULL if corresponding information is not
|
||||
// needed. The values in these pointers are only valid on successful (non-NULL)
|
||||
// return.
|
||||
WEBP_EXTERN uint8_t* WebPIDecGetRGB(
|
||||
const WebPIDecoder* idec, int* last_y,
|
||||
int* width, int* height, int* stride);
|
||||
|
||||
// Same as above function to get a YUVA image. Returns pointer to the luma
|
||||
// plane or NULL in case of error. If there is no alpha information
|
||||
// the alpha pointer '*a' will be returned NULL.
|
||||
WEBP_EXTERN uint8_t* WebPIDecGetYUVA(
|
||||
const WebPIDecoder* idec, int* last_y,
|
||||
uint8_t** u, uint8_t** v, uint8_t** a,
|
||||
int* width, int* height, int* stride, int* uv_stride, int* a_stride);
|
||||
|
||||
// Deprecated alpha-less version of WebPIDecGetYUVA(): it will ignore the
|
||||
// alpha information (if present). Kept for backward compatibility.
|
||||
static WEBP_INLINE uint8_t* WebPIDecGetYUV(
|
||||
const WebPIDecoder* idec, int* last_y, uint8_t** u, uint8_t** v,
|
||||
int* width, int* height, int* stride, int* uv_stride) {
|
||||
return WebPIDecGetYUVA(idec, last_y, u, v, NULL, width, height,
|
||||
stride, uv_stride, NULL);
|
||||
}
|
||||
|
||||
// Generic call to retrieve information about the displayable area.
|
||||
// If non NULL, the left/right/width/height pointers are filled with the visible
|
||||
// rectangular area so far.
|
||||
// Returns NULL in case the incremental decoder object is in an invalid state.
|
||||
// Otherwise returns the pointer to the internal representation. This structure
|
||||
// is read-only, tied to WebPIDecoder's lifespan and should not be modified.
|
||||
WEBP_EXTERN const WebPDecBuffer* WebPIDecodedArea(
|
||||
const WebPIDecoder* idec, int* left, int* top, int* width, int* height);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Advanced decoding parametrization
|
||||
//
|
||||
// Code sample for using the advanced decoding API
|
||||
/*
|
||||
// A) Init a configuration object
|
||||
WebPDecoderConfig config;
|
||||
CHECK(WebPInitDecoderConfig(&config));
|
||||
|
||||
// B) optional: retrieve the bitstream's features.
|
||||
CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
|
||||
|
||||
// C) Adjust 'config', if needed
|
||||
config.no_fancy_upsampling = 1;
|
||||
config.output.colorspace = MODE_BGRA;
|
||||
// etc.
|
||||
|
||||
// Note that you can also make config.output point to an externally
|
||||
// supplied memory buffer, provided it's big enough to store the decoded
|
||||
// picture. Otherwise, config.output will just be used to allocate memory
|
||||
// and store the decoded picture.
|
||||
|
||||
// D) Decode!
|
||||
CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
|
||||
|
||||
// E) Decoded image is now in config.output (and config.output.u.RGBA)
|
||||
|
||||
// F) Reclaim memory allocated in config's object. It's safe to call
|
||||
// this function even if the memory is external and wasn't allocated
|
||||
// by WebPDecode().
|
||||
WebPFreeDecBuffer(&config.output);
|
||||
*/
|
||||
|
||||
// Features gathered from the bitstream
|
||||
struct WebPBitstreamFeatures {
|
||||
int width; // Width in pixels, as read from the bitstream.
|
||||
int height; // Height in pixels, as read from the bitstream.
|
||||
int has_alpha; // True if the bitstream contains an alpha channel.
|
||||
int has_animation; // True if the bitstream is an animation.
|
||||
int format; // 0 = undefined (/mixed), 1 = lossy, 2 = lossless
|
||||
|
||||
uint32_t pad[5]; // padding for later use
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN VP8StatusCode WebPGetFeaturesInternal(
|
||||
const uint8_t*, size_t, WebPBitstreamFeatures*, int);
|
||||
|
||||
// Retrieve features from the bitstream. The *features structure is filled
|
||||
// with information gathered from the bitstream.
|
||||
// Returns VP8_STATUS_OK when the features are successfully retrieved. Returns
|
||||
// VP8_STATUS_NOT_ENOUGH_DATA when more data is needed to retrieve the
|
||||
// features from headers. Returns error in other cases.
|
||||
// Note: The following chunk sequences (before the raw VP8/VP8L data) are
|
||||
// considered valid by this function:
|
||||
// RIFF + VP8(L)
|
||||
// RIFF + VP8X + (optional chunks) + VP8(L)
|
||||
// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose.
|
||||
static WEBP_INLINE VP8StatusCode WebPGetFeatures(
|
||||
const uint8_t* data, size_t data_size,
|
||||
WebPBitstreamFeatures* features) {
|
||||
return WebPGetFeaturesInternal(data, data_size, features,
|
||||
WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Decoding options
|
||||
struct WebPDecoderOptions {
|
||||
int bypass_filtering; // if true, skip the in-loop filtering
|
||||
int no_fancy_upsampling; // if true, use faster pointwise upsampler
|
||||
int use_cropping; // if true, cropping is applied _first_
|
||||
int crop_left, crop_top; // top-left position for cropping.
|
||||
// Will be snapped to even values.
|
||||
int crop_width, crop_height; // dimension of the cropping area
|
||||
int use_scaling; // if true, scaling is applied _afterward_
|
||||
int scaled_width, scaled_height; // final resolution
|
||||
int use_threads; // if true, use multi-threaded decoding
|
||||
int dithering_strength; // dithering strength (0=Off, 100=full)
|
||||
int flip; // if true, flip output vertically
|
||||
int alpha_dithering_strength; // alpha dithering strength in [0..100]
|
||||
|
||||
uint32_t pad[5]; // padding for later use
|
||||
};
|
||||
|
||||
// Main object storing the configuration for advanced decoding.
|
||||
struct WebPDecoderConfig {
|
||||
WebPBitstreamFeatures input; // Immutable bitstream features (optional)
|
||||
WebPDecBuffer output; // Output buffer (can point to external mem)
|
||||
WebPDecoderOptions options; // Decoding options
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPInitDecoderConfigInternal(WebPDecoderConfig*, int);
|
||||
|
||||
// Initialize the configuration as empty. This function must always be
|
||||
// called first, unless WebPGetFeatures() is to be called.
|
||||
// Returns false in case of mismatched version.
|
||||
static WEBP_INLINE int WebPInitDecoderConfig(WebPDecoderConfig* config) {
|
||||
return WebPInitDecoderConfigInternal(config, WEBP_DECODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Instantiate a new incremental decoder object with the requested
|
||||
// configuration. The bitstream can be passed using 'data' and 'data_size'
|
||||
// parameter, in which case the features will be parsed and stored into
|
||||
// config->input. Otherwise, 'data' can be NULL and no parsing will occur.
|
||||
// Note that 'config' can be NULL too, in which case a default configuration
|
||||
// is used. If 'config' is not NULL, it must outlive the WebPIDecoder object
|
||||
// as some references to its fields will be used. No internal copy of 'config'
|
||||
// is made.
|
||||
// The return WebPIDecoder object must always be deleted calling WebPIDelete().
|
||||
// Returns NULL in case of error (and config->status will then reflect
|
||||
// the error condition, if available).
|
||||
WEBP_EXTERN WebPIDecoder* WebPIDecode(const uint8_t* data, size_t data_size,
|
||||
WebPDecoderConfig* config);
|
||||
|
||||
// Non-incremental version. This version decodes the full data at once, taking
|
||||
// 'config' into account. Returns decoding status (which should be VP8_STATUS_OK
|
||||
// if the decoding was successful). Note that 'config' cannot be NULL.
|
||||
WEBP_EXTERN VP8StatusCode WebPDecode(const uint8_t* data, size_t data_size,
|
||||
WebPDecoderConfig* config);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_DECODE_H_
|
||||
@@ -0,0 +1,363 @@
|
||||
// Copyright 2012 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Demux API.
|
||||
// Enables extraction of image and extended format data from WebP files.
|
||||
|
||||
// Code Example: Demuxing WebP data to extract all the frames, ICC profile
|
||||
// and EXIF/XMP metadata.
|
||||
/*
|
||||
WebPDemuxer* demux = WebPDemux(&webp_data);
|
||||
|
||||
uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
|
||||
uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
|
||||
// ... (Get information about the features present in the WebP file).
|
||||
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
|
||||
|
||||
// ... (Iterate over all frames).
|
||||
WebPIterator iter;
|
||||
if (WebPDemuxGetFrame(demux, 1, &iter)) {
|
||||
do {
|
||||
// ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
|
||||
// ... and get other frame properties like width, height, offsets etc.
|
||||
// ... see 'struct WebPIterator' below for more info).
|
||||
} while (WebPDemuxNextFrame(&iter));
|
||||
WebPDemuxReleaseIterator(&iter);
|
||||
}
|
||||
|
||||
// ... (Extract metadata).
|
||||
WebPChunkIterator chunk_iter;
|
||||
if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
|
||||
// ... (Consume the ICC profile in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
|
||||
// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
|
||||
// ... (Consume the XMP metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
WebPDemuxDelete(demux);
|
||||
*/
|
||||
|
||||
#ifndef WEBP_WEBP_DEMUX_H_
|
||||
#define WEBP_WEBP_DEMUX_H_
|
||||
|
||||
#include "./decode.h" // for WEBP_CSP_MODE
|
||||
#include "./mux_types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_DEMUX_ABI_VERSION 0x0107 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPDemuxState WebPDemuxState;
|
||||
// typedef enum WebPFormatFeature WebPFormatFeature;
|
||||
typedef struct WebPDemuxer WebPDemuxer;
|
||||
typedef struct WebPIterator WebPIterator;
|
||||
typedef struct WebPChunkIterator WebPChunkIterator;
|
||||
typedef struct WebPAnimInfo WebPAnimInfo;
|
||||
typedef struct WebPAnimDecoderOptions WebPAnimDecoderOptions;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// Returns the version number of the demux library, packed in hexadecimal using
|
||||
// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetDemuxVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Life of a Demux object
|
||||
|
||||
typedef enum WebPDemuxState {
|
||||
WEBP_DEMUX_PARSE_ERROR = -1, // An error occurred while parsing.
|
||||
WEBP_DEMUX_PARSING_HEADER = 0, // Not enough data to parse full header.
|
||||
WEBP_DEMUX_PARSED_HEADER = 1, // Header parsing complete,
|
||||
// data may be available.
|
||||
WEBP_DEMUX_DONE = 2 // Entire file has been parsed.
|
||||
} WebPDemuxState;
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPDemuxer* WebPDemuxInternal(
|
||||
const WebPData*, int, WebPDemuxState*, int);
|
||||
|
||||
// Parses the full WebP file given by 'data'. For single images the WebP file
|
||||
// header alone or the file header and the chunk header may be absent.
|
||||
// Returns a WebPDemuxer object on successful parse, NULL otherwise.
|
||||
static WEBP_INLINE WebPDemuxer* WebPDemux(const WebPData* data) {
|
||||
return WebPDemuxInternal(data, 0, NULL, WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Parses the possibly incomplete WebP file given by 'data'.
|
||||
// If 'state' is non-NULL it will be set to indicate the status of the demuxer.
|
||||
// Returns NULL in case of error or if there isn't enough data to start parsing;
|
||||
// and a WebPDemuxer object on successful parse.
|
||||
// Note that WebPDemuxer keeps internal pointers to 'data' memory segment.
|
||||
// If this data is volatile, the demuxer object should be deleted (by calling
|
||||
// WebPDemuxDelete()) and WebPDemuxPartial() called again on the new data.
|
||||
// This is usually an inexpensive operation.
|
||||
static WEBP_INLINE WebPDemuxer* WebPDemuxPartial(
|
||||
const WebPData* data, WebPDemuxState* state) {
|
||||
return WebPDemuxInternal(data, 1, state, WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Frees memory associated with 'dmux'.
|
||||
WEBP_EXTERN void WebPDemuxDelete(WebPDemuxer* dmux);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Data/information extraction.
|
||||
|
||||
typedef enum WebPFormatFeature {
|
||||
WEBP_FF_FORMAT_FLAGS, // bit-wise combination of WebPFeatureFlags
|
||||
// corresponding to the 'VP8X' chunk (if present).
|
||||
WEBP_FF_CANVAS_WIDTH,
|
||||
WEBP_FF_CANVAS_HEIGHT,
|
||||
WEBP_FF_LOOP_COUNT, // only relevant for animated file
|
||||
WEBP_FF_BACKGROUND_COLOR, // idem.
|
||||
WEBP_FF_FRAME_COUNT // Number of frames present in the demux object.
|
||||
// In case of a partial demux, this is the number
|
||||
// of frames seen so far, with the last frame
|
||||
// possibly being partial.
|
||||
} WebPFormatFeature;
|
||||
|
||||
// Get the 'feature' value from the 'dmux'.
|
||||
// NOTE: values are only valid if WebPDemux() was used or WebPDemuxPartial()
|
||||
// returned a state > WEBP_DEMUX_PARSING_HEADER.
|
||||
// If 'feature' is WEBP_FF_FORMAT_FLAGS, the returned value is a bit-wise
|
||||
// combination of WebPFeatureFlags values.
|
||||
// If 'feature' is WEBP_FF_LOOP_COUNT, WEBP_FF_BACKGROUND_COLOR, the returned
|
||||
// value is only meaningful if the bitstream is animated.
|
||||
WEBP_EXTERN uint32_t WebPDemuxGetI(
|
||||
const WebPDemuxer* dmux, WebPFormatFeature feature);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Frame iteration.
|
||||
|
||||
struct WebPIterator {
|
||||
int frame_num;
|
||||
int num_frames; // equivalent to WEBP_FF_FRAME_COUNT.
|
||||
int x_offset, y_offset; // offset relative to the canvas.
|
||||
int width, height; // dimensions of this frame.
|
||||
int duration; // display duration in milliseconds.
|
||||
WebPMuxAnimDispose dispose_method; // dispose method for the frame.
|
||||
int complete; // true if 'fragment' contains a full frame. partial images
|
||||
// may still be decoded with the WebP incremental decoder.
|
||||
WebPData fragment; // The frame given by 'frame_num'. Note for historical
|
||||
// reasons this is called a fragment.
|
||||
int has_alpha; // True if the frame contains transparency.
|
||||
WebPMuxAnimBlend blend_method; // Blend operation for the frame.
|
||||
|
||||
uint32_t pad[2]; // padding for later use.
|
||||
void* private_; // for internal use only.
|
||||
};
|
||||
|
||||
// Retrieves frame 'frame_number' from 'dmux'.
|
||||
// 'iter->fragment' points to the frame on return from this function.
|
||||
// Setting 'frame_number' equal to 0 will return the last frame of the image.
|
||||
// Returns false if 'dmux' is NULL or frame 'frame_number' is not present.
|
||||
// Call WebPDemuxReleaseIterator() when use of the iterator is complete.
|
||||
// NOTE: 'dmux' must persist for the lifetime of 'iter'.
|
||||
WEBP_EXTERN int WebPDemuxGetFrame(
|
||||
const WebPDemuxer* dmux, int frame_number, WebPIterator* iter);
|
||||
|
||||
// Sets 'iter->fragment' to point to the next ('iter->frame_num' + 1) or
|
||||
// previous ('iter->frame_num' - 1) frame. These functions do not loop.
|
||||
// Returns true on success, false otherwise.
|
||||
WEBP_EXTERN int WebPDemuxNextFrame(WebPIterator* iter);
|
||||
WEBP_EXTERN int WebPDemuxPrevFrame(WebPIterator* iter);
|
||||
|
||||
// Releases any memory associated with 'iter'.
|
||||
// Must be called before any subsequent calls to WebPDemuxGetChunk() on the same
|
||||
// iter. Also, must be called before destroying the associated WebPDemuxer with
|
||||
// WebPDemuxDelete().
|
||||
WEBP_EXTERN void WebPDemuxReleaseIterator(WebPIterator* iter);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Chunk iteration.
|
||||
|
||||
struct WebPChunkIterator {
|
||||
// The current and total number of chunks with the fourcc given to
|
||||
// WebPDemuxGetChunk().
|
||||
int chunk_num;
|
||||
int num_chunks;
|
||||
WebPData chunk; // The payload of the chunk.
|
||||
|
||||
uint32_t pad[6]; // padding for later use
|
||||
void* private_;
|
||||
};
|
||||
|
||||
// Retrieves the 'chunk_number' instance of the chunk with id 'fourcc' from
|
||||
// 'dmux'.
|
||||
// 'fourcc' is a character array containing the fourcc of the chunk to return,
|
||||
// e.g., "ICCP", "XMP ", "EXIF", etc.
|
||||
// Setting 'chunk_number' equal to 0 will return the last chunk in a set.
|
||||
// Returns true if the chunk is found, false otherwise. Image related chunk
|
||||
// payloads are accessed through WebPDemuxGetFrame() and related functions.
|
||||
// Call WebPDemuxReleaseChunkIterator() when use of the iterator is complete.
|
||||
// NOTE: 'dmux' must persist for the lifetime of the iterator.
|
||||
WEBP_EXTERN int WebPDemuxGetChunk(const WebPDemuxer* dmux,
|
||||
const char fourcc[4], int chunk_number,
|
||||
WebPChunkIterator* iter);
|
||||
|
||||
// Sets 'iter->chunk' to point to the next ('iter->chunk_num' + 1) or previous
|
||||
// ('iter->chunk_num' - 1) chunk. These functions do not loop.
|
||||
// Returns true on success, false otherwise.
|
||||
WEBP_EXTERN int WebPDemuxNextChunk(WebPChunkIterator* iter);
|
||||
WEBP_EXTERN int WebPDemuxPrevChunk(WebPChunkIterator* iter);
|
||||
|
||||
// Releases any memory associated with 'iter'.
|
||||
// Must be called before destroying the associated WebPDemuxer with
|
||||
// WebPDemuxDelete().
|
||||
WEBP_EXTERN void WebPDemuxReleaseChunkIterator(WebPChunkIterator* iter);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPAnimDecoder API
|
||||
//
|
||||
// This API allows decoding (possibly) animated WebP images.
|
||||
//
|
||||
// Code Example:
|
||||
/*
|
||||
WebPAnimDecoderOptions dec_options;
|
||||
WebPAnimDecoderOptionsInit(&dec_options);
|
||||
// Tune 'dec_options' as needed.
|
||||
WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
|
||||
WebPAnimInfo anim_info;
|
||||
WebPAnimDecoderGetInfo(dec, &anim_info);
|
||||
for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
|
||||
while (WebPAnimDecoderHasMoreFrames(dec)) {
|
||||
uint8_t* buf;
|
||||
int timestamp;
|
||||
WebPAnimDecoderGetNext(dec, &buf, ×tamp);
|
||||
// ... (Render 'buf' based on 'timestamp').
|
||||
// ... (Do NOT free 'buf', as it is owned by 'dec').
|
||||
}
|
||||
WebPAnimDecoderReset(dec);
|
||||
}
|
||||
const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
|
||||
// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
|
||||
WebPAnimDecoderDelete(dec);
|
||||
*/
|
||||
|
||||
typedef struct WebPAnimDecoder WebPAnimDecoder; // Main opaque object.
|
||||
|
||||
// Global options.
|
||||
struct WebPAnimDecoderOptions {
|
||||
// Output colorspace. Only the following modes are supported:
|
||||
// MODE_RGBA, MODE_BGRA, MODE_rgbA and MODE_bgrA.
|
||||
WEBP_CSP_MODE color_mode;
|
||||
int use_threads; // If true, use multi-threaded decoding.
|
||||
uint32_t padding[7]; // Padding for later use.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN int WebPAnimDecoderOptionsInitInternal(
|
||||
WebPAnimDecoderOptions*, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPAnimDecoderOptions
|
||||
// structure before modification. Returns false in case of version mismatch.
|
||||
// WebPAnimDecoderOptionsInit() must have succeeded before using the
|
||||
// 'dec_options' object.
|
||||
static WEBP_INLINE int WebPAnimDecoderOptionsInit(
|
||||
WebPAnimDecoderOptions* dec_options) {
|
||||
return WebPAnimDecoderOptionsInitInternal(dec_options,
|
||||
WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN WebPAnimDecoder* WebPAnimDecoderNewInternal(
|
||||
const WebPData*, const WebPAnimDecoderOptions*, int);
|
||||
|
||||
// Creates and initializes a WebPAnimDecoder object.
|
||||
// Parameters:
|
||||
// webp_data - (in) WebP bitstream. This should remain unchanged during the
|
||||
// lifetime of the output WebPAnimDecoder object.
|
||||
// dec_options - (in) decoding options. Can be passed NULL to choose
|
||||
// reasonable defaults (in particular, color mode MODE_RGBA
|
||||
// will be picked).
|
||||
// Returns:
|
||||
// A pointer to the newly created WebPAnimDecoder object, or NULL in case of
|
||||
// parsing error, invalid option or memory error.
|
||||
static WEBP_INLINE WebPAnimDecoder* WebPAnimDecoderNew(
|
||||
const WebPData* webp_data, const WebPAnimDecoderOptions* dec_options) {
|
||||
return WebPAnimDecoderNewInternal(webp_data, dec_options,
|
||||
WEBP_DEMUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Global information about the animation..
|
||||
struct WebPAnimInfo {
|
||||
uint32_t canvas_width;
|
||||
uint32_t canvas_height;
|
||||
uint32_t loop_count;
|
||||
uint32_t bgcolor;
|
||||
uint32_t frame_count;
|
||||
uint32_t pad[4]; // padding for later use
|
||||
};
|
||||
|
||||
// Get global information about the animation.
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance to get information from.
|
||||
// info - (out) global information fetched from the animation.
|
||||
// Returns:
|
||||
// True on success.
|
||||
WEBP_EXTERN int WebPAnimDecoderGetInfo(const WebPAnimDecoder* dec,
|
||||
WebPAnimInfo* info);
|
||||
|
||||
// Fetch the next frame from 'dec' based on options supplied to
|
||||
// WebPAnimDecoderNew(). This will be a fully reconstructed canvas of size
|
||||
// 'canvas_width * 4 * canvas_height', and not just the frame sub-rectangle. The
|
||||
// returned buffer 'buf' is valid only until the next call to
|
||||
// WebPAnimDecoderGetNext(), WebPAnimDecoderReset() or WebPAnimDecoderDelete().
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance from which the next frame is to be fetched.
|
||||
// buf - (out) decoded frame.
|
||||
// timestamp - (out) timestamp of the frame in milliseconds.
|
||||
// Returns:
|
||||
// False if any of the arguments are NULL, or if there is a parsing or
|
||||
// decoding error, or if there are no more frames. Otherwise, returns true.
|
||||
WEBP_EXTERN int WebPAnimDecoderGetNext(WebPAnimDecoder* dec,
|
||||
uint8_t** buf, int* timestamp);
|
||||
|
||||
// Check if there are more frames left to decode.
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance to be checked.
|
||||
// Returns:
|
||||
// True if 'dec' is not NULL and some frames are yet to be decoded.
|
||||
// Otherwise, returns false.
|
||||
WEBP_EXTERN int WebPAnimDecoderHasMoreFrames(const WebPAnimDecoder* dec);
|
||||
|
||||
// Resets the WebPAnimDecoder object, so that next call to
|
||||
// WebPAnimDecoderGetNext() will restart decoding from 1st frame. This would be
|
||||
// helpful when all frames need to be decoded multiple times (e.g.
|
||||
// info.loop_count times) without destroying and recreating the 'dec' object.
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance to be reset
|
||||
WEBP_EXTERN void WebPAnimDecoderReset(WebPAnimDecoder* dec);
|
||||
|
||||
// Grab the internal demuxer object.
|
||||
// Getting the demuxer object can be useful if one wants to use operations only
|
||||
// available through demuxer; e.g. to get XMP/EXIF/ICC metadata. The returned
|
||||
// demuxer object is owned by 'dec' and is valid only until the next call to
|
||||
// WebPAnimDecoderDelete().
|
||||
//
|
||||
// Parameters:
|
||||
// dec - (in) decoder instance from which the demuxer object is to be fetched.
|
||||
WEBP_EXTERN const WebPDemuxer* WebPAnimDecoderGetDemuxer(
|
||||
const WebPAnimDecoder* dec);
|
||||
|
||||
// Deletes the WebPAnimDecoder object.
|
||||
// Parameters:
|
||||
// dec - (in/out) decoder instance to be deleted
|
||||
WEBP_EXTERN void WebPAnimDecoderDelete(WebPAnimDecoder* dec);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_DEMUX_H_
|
||||
@@ -0,0 +1,552 @@
|
||||
// Copyright 2011 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// WebP encoder: main interface
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_ENCODE_H_
|
||||
#define WEBP_WEBP_ENCODE_H_
|
||||
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_ENCODER_ABI_VERSION 0x020f // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPImageHint WebPImageHint;
|
||||
// typedef enum WebPEncCSP WebPEncCSP;
|
||||
// typedef enum WebPPreset WebPPreset;
|
||||
// typedef enum WebPEncodingError WebPEncodingError;
|
||||
typedef struct WebPConfig WebPConfig;
|
||||
typedef struct WebPPicture WebPPicture; // main structure for I/O
|
||||
typedef struct WebPAuxStats WebPAuxStats;
|
||||
typedef struct WebPMemoryWriter WebPMemoryWriter;
|
||||
|
||||
// Return the encoder's version number, packed in hexadecimal using 8bits for
|
||||
// each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetEncoderVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// One-stop-shop call! No questions asked:
|
||||
|
||||
// Returns the size of the compressed data (pointed to by *output), or 0 if
|
||||
// an error occurred. The compressed data must be released by the caller
|
||||
// using the call 'WebPFree(*output)'.
|
||||
// These functions compress using the lossy format, and the quality_factor
|
||||
// can go from 0 (smaller output, lower quality) to 100 (best quality,
|
||||
// larger output).
|
||||
WEBP_EXTERN size_t WebPEncodeRGB(const uint8_t* rgb,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeBGR(const uint8_t* bgr,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeRGBA(const uint8_t* rgba,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeBGRA(const uint8_t* bgra,
|
||||
int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
|
||||
// These functions are the equivalent of the above, but compressing in a
|
||||
// lossless manner. Files are usually larger than lossy format, but will
|
||||
// not suffer any compression loss.
|
||||
// Note these functions, like the lossy versions, use the library's default
|
||||
// settings. For lossless this means 'exact' is disabled. RGB values in
|
||||
// transparent areas will be modified to improve compression. To avoid this,
|
||||
// use WebPEncode() and set WebPConfig::exact to 1.
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessRGB(const uint8_t* rgb,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessBGR(const uint8_t* bgr,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessRGBA(const uint8_t* rgba,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
WEBP_EXTERN size_t WebPEncodeLosslessBGRA(const uint8_t* bgra,
|
||||
int width, int height, int stride,
|
||||
uint8_t** output);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Coding parameters
|
||||
|
||||
// Image characteristics hint for the underlying encoder.
|
||||
typedef enum WebPImageHint {
|
||||
WEBP_HINT_DEFAULT = 0, // default preset.
|
||||
WEBP_HINT_PICTURE, // digital picture, like portrait, inner shot
|
||||
WEBP_HINT_PHOTO, // outdoor photograph, with natural lighting
|
||||
WEBP_HINT_GRAPH, // Discrete tone image (graph, map-tile etc).
|
||||
WEBP_HINT_LAST
|
||||
} WebPImageHint;
|
||||
|
||||
// Compression parameters.
|
||||
struct WebPConfig {
|
||||
int lossless; // Lossless encoding (0=lossy(default), 1=lossless).
|
||||
float quality; // between 0 and 100. For lossy, 0 gives the smallest
|
||||
// size and 100 the largest. For lossless, this
|
||||
// parameter is the amount of effort put into the
|
||||
// compression: 0 is the fastest but gives larger
|
||||
// files compared to the slowest, but best, 100.
|
||||
int method; // quality/speed trade-off (0=fast, 6=slower-better)
|
||||
|
||||
WebPImageHint image_hint; // Hint for image type (lossless only for now).
|
||||
|
||||
int target_size; // if non-zero, set the desired target size in bytes.
|
||||
// Takes precedence over the 'compression' parameter.
|
||||
float target_PSNR; // if non-zero, specifies the minimal distortion to
|
||||
// try to achieve. Takes precedence over target_size.
|
||||
int segments; // maximum number of segments to use, in [1..4]
|
||||
int sns_strength; // Spatial Noise Shaping. 0=off, 100=maximum.
|
||||
int filter_strength; // range: [0 = off .. 100 = strongest]
|
||||
int filter_sharpness; // range: [0 = off .. 7 = least sharp]
|
||||
int filter_type; // filtering type: 0 = simple, 1 = strong (only used
|
||||
// if filter_strength > 0 or autofilter > 0)
|
||||
int autofilter; // Auto adjust filter's strength [0 = off, 1 = on]
|
||||
int alpha_compression; // Algorithm for encoding the alpha plane (0 = none,
|
||||
// 1 = compressed with WebP lossless). Default is 1.
|
||||
int alpha_filtering; // Predictive filtering method for alpha plane.
|
||||
// 0: none, 1: fast, 2: best. Default if 1.
|
||||
int alpha_quality; // Between 0 (smallest size) and 100 (lossless).
|
||||
// Default is 100.
|
||||
int pass; // number of entropy-analysis passes (in [1..10]).
|
||||
|
||||
int show_compressed; // if true, export the compressed picture back.
|
||||
// In-loop filtering is not applied.
|
||||
int preprocessing; // preprocessing filter:
|
||||
// 0=none, 1=segment-smooth, 2=pseudo-random dithering
|
||||
int partitions; // log2(number of token partitions) in [0..3]. Default
|
||||
// is set to 0 for easier progressive decoding.
|
||||
int partition_limit; // quality degradation allowed to fit the 512k limit
|
||||
// on prediction modes coding (0: no degradation,
|
||||
// 100: maximum possible degradation).
|
||||
int emulate_jpeg_size; // If true, compression parameters will be remapped
|
||||
// to better match the expected output size from
|
||||
// JPEG compression. Generally, the output size will
|
||||
// be similar but the degradation will be lower.
|
||||
int thread_level; // If non-zero, try and use multi-threaded encoding.
|
||||
int low_memory; // If set, reduce memory usage (but increase CPU use).
|
||||
|
||||
int near_lossless; // Near lossless encoding [0 = max loss .. 100 = off
|
||||
// (default)].
|
||||
int exact; // if non-zero, preserve the exact RGB values under
|
||||
// transparent area. Otherwise, discard this invisible
|
||||
// RGB information for better compression. The default
|
||||
// value is 0.
|
||||
|
||||
int use_delta_palette; // reserved for future lossless feature
|
||||
int use_sharp_yuv; // if needed, use sharp (and slow) RGB->YUV conversion
|
||||
|
||||
int qmin; // minimum permissible quality factor
|
||||
int qmax; // maximum permissible quality factor
|
||||
};
|
||||
|
||||
// Enumerate some predefined settings for WebPConfig, depending on the type
|
||||
// of source picture. These presets are used when calling WebPConfigPreset().
|
||||
typedef enum WebPPreset {
|
||||
WEBP_PRESET_DEFAULT = 0, // default preset.
|
||||
WEBP_PRESET_PICTURE, // digital picture, like portrait, inner shot
|
||||
WEBP_PRESET_PHOTO, // outdoor photograph, with natural lighting
|
||||
WEBP_PRESET_DRAWING, // hand or line drawing, with high-contrast details
|
||||
WEBP_PRESET_ICON, // small-sized colorful images
|
||||
WEBP_PRESET_TEXT // text-like
|
||||
} WebPPreset;
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPConfigInitInternal(WebPConfig*, WebPPreset, float, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPConfig structure before
|
||||
// modification. Returns false in case of version mismatch. WebPConfigInit()
|
||||
// must have succeeded before using the 'config' object.
|
||||
// Note that the default values are lossless=0 and quality=75.
|
||||
static WEBP_INLINE int WebPConfigInit(WebPConfig* config) {
|
||||
return WebPConfigInitInternal(config, WEBP_PRESET_DEFAULT, 75.f,
|
||||
WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// This function will initialize the configuration according to a predefined
|
||||
// set of parameters (referred to by 'preset') and a given quality factor.
|
||||
// This function can be called as a replacement to WebPConfigInit(). Will
|
||||
// return false in case of error.
|
||||
static WEBP_INLINE int WebPConfigPreset(WebPConfig* config,
|
||||
WebPPreset preset, float quality) {
|
||||
return WebPConfigInitInternal(config, preset, quality,
|
||||
WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Activate the lossless compression mode with the desired efficiency level
|
||||
// between 0 (fastest, lowest compression) and 9 (slower, best compression).
|
||||
// A good default level is '6', providing a fair tradeoff between compression
|
||||
// speed and final compressed size.
|
||||
// This function will overwrite several fields from config: 'method', 'quality'
|
||||
// and 'lossless'. Returns false in case of parameter error.
|
||||
WEBP_EXTERN int WebPConfigLosslessPreset(WebPConfig* config, int level);
|
||||
|
||||
// Returns true if 'config' is non-NULL and all configuration parameters are
|
||||
// within their valid ranges.
|
||||
WEBP_EXTERN int WebPValidateConfig(const WebPConfig* config);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Input / Output
|
||||
// Structure for storing auxiliary statistics.
|
||||
|
||||
struct WebPAuxStats {
|
||||
int coded_size; // final size
|
||||
|
||||
float PSNR[5]; // peak-signal-to-noise ratio for Y/U/V/All/Alpha
|
||||
int block_count[3]; // number of intra4/intra16/skipped macroblocks
|
||||
int header_bytes[2]; // approximate number of bytes spent for header
|
||||
// and mode-partition #0
|
||||
int residual_bytes[3][4]; // approximate number of bytes spent for
|
||||
// DC/AC/uv coefficients for each (0..3) segments.
|
||||
int segment_size[4]; // number of macroblocks in each segments
|
||||
int segment_quant[4]; // quantizer values for each segments
|
||||
int segment_level[4]; // filtering strength for each segments [0..63]
|
||||
|
||||
int alpha_data_size; // size of the transparency data
|
||||
int layer_data_size; // size of the enhancement layer data
|
||||
|
||||
// lossless encoder statistics
|
||||
uint32_t lossless_features; // bit0:predictor bit1:cross-color transform
|
||||
// bit2:subtract-green bit3:color indexing
|
||||
int histogram_bits; // number of precision bits of histogram
|
||||
int transform_bits; // precision bits for transform
|
||||
int cache_bits; // number of bits for color cache lookup
|
||||
int palette_size; // number of color in palette, if used
|
||||
int lossless_size; // final lossless size
|
||||
int lossless_hdr_size; // lossless header (transform, huffman etc) size
|
||||
int lossless_data_size; // lossless image data size
|
||||
|
||||
uint32_t pad[2]; // padding for later use
|
||||
};
|
||||
|
||||
// Signature for output function. Should return true if writing was successful.
|
||||
// data/data_size is the segment of data to write, and 'picture' is for
|
||||
// reference (and so one can make use of picture->custom_ptr).
|
||||
typedef int (*WebPWriterFunction)(const uint8_t* data, size_t data_size,
|
||||
const WebPPicture* picture);
|
||||
|
||||
// WebPMemoryWrite: a special WebPWriterFunction that writes to memory using
|
||||
// the following WebPMemoryWriter object (to be set as a custom_ptr).
|
||||
struct WebPMemoryWriter {
|
||||
uint8_t* mem; // final buffer (of size 'max_size', larger than 'size').
|
||||
size_t size; // final size
|
||||
size_t max_size; // total capacity
|
||||
uint32_t pad[1]; // padding for later use
|
||||
};
|
||||
|
||||
// The following must be called first before any use.
|
||||
WEBP_EXTERN void WebPMemoryWriterInit(WebPMemoryWriter* writer);
|
||||
|
||||
// The following must be called to deallocate writer->mem memory. The 'writer'
|
||||
// object itself is not deallocated.
|
||||
WEBP_EXTERN void WebPMemoryWriterClear(WebPMemoryWriter* writer);
|
||||
// The custom writer to be used with WebPMemoryWriter as custom_ptr. Upon
|
||||
// completion, writer.mem and writer.size will hold the coded data.
|
||||
// writer.mem must be freed by calling WebPMemoryWriterClear.
|
||||
WEBP_EXTERN int WebPMemoryWrite(const uint8_t* data, size_t data_size,
|
||||
const WebPPicture* picture);
|
||||
|
||||
// Progress hook, called from time to time to report progress. It can return
|
||||
// false to request an abort of the encoding process, or true otherwise if
|
||||
// everything is OK.
|
||||
typedef int (*WebPProgressHook)(int percent, const WebPPicture* picture);
|
||||
|
||||
// Color spaces.
|
||||
typedef enum WebPEncCSP {
|
||||
// chroma sampling
|
||||
WEBP_YUV420 = 0, // 4:2:0
|
||||
WEBP_YUV420A = 4, // alpha channel variant
|
||||
WEBP_CSP_UV_MASK = 3, // bit-mask to get the UV sampling factors
|
||||
WEBP_CSP_ALPHA_BIT = 4 // bit that is set if alpha is present
|
||||
} WebPEncCSP;
|
||||
|
||||
// Encoding error conditions.
|
||||
typedef enum WebPEncodingError {
|
||||
VP8_ENC_OK = 0,
|
||||
VP8_ENC_ERROR_OUT_OF_MEMORY, // memory error allocating objects
|
||||
VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY, // memory error while flushing bits
|
||||
VP8_ENC_ERROR_NULL_PARAMETER, // a pointer parameter is NULL
|
||||
VP8_ENC_ERROR_INVALID_CONFIGURATION, // configuration is invalid
|
||||
VP8_ENC_ERROR_BAD_DIMENSION, // picture has invalid width/height
|
||||
VP8_ENC_ERROR_PARTITION0_OVERFLOW, // partition is bigger than 512k
|
||||
VP8_ENC_ERROR_PARTITION_OVERFLOW, // partition is bigger than 16M
|
||||
VP8_ENC_ERROR_BAD_WRITE, // error while flushing bytes
|
||||
VP8_ENC_ERROR_FILE_TOO_BIG, // file is bigger than 4G
|
||||
VP8_ENC_ERROR_USER_ABORT, // abort request by user
|
||||
VP8_ENC_ERROR_LAST // list terminator. always last.
|
||||
} WebPEncodingError;
|
||||
|
||||
// maximum width/height allowed (inclusive), in pixels
|
||||
#define WEBP_MAX_DIMENSION 16383
|
||||
|
||||
// Main exchange structure (input samples, output bytes, statistics)
|
||||
//
|
||||
// Once WebPPictureInit() has been called, it's ok to make all the INPUT fields
|
||||
// (use_argb, y/u/v, argb, ...) point to user-owned data, even if
|
||||
// WebPPictureAlloc() has been called. Depending on the value use_argb,
|
||||
// it's guaranteed that either *argb or *y/*u/*v content will be kept untouched.
|
||||
struct WebPPicture {
|
||||
// INPUT
|
||||
//////////////
|
||||
// Main flag for encoder selecting between ARGB or YUV input.
|
||||
// It is recommended to use ARGB input (*argb, argb_stride) for lossless
|
||||
// compression, and YUV input (*y, *u, *v, etc.) for lossy compression
|
||||
// since these are the respective native colorspace for these formats.
|
||||
int use_argb;
|
||||
|
||||
// YUV input (mostly used for input to lossy compression)
|
||||
WebPEncCSP colorspace; // colorspace: should be YUV420 for now (=Y'CbCr).
|
||||
int width, height; // dimensions (less or equal to WEBP_MAX_DIMENSION)
|
||||
uint8_t* y, *u, *v; // pointers to luma/chroma planes.
|
||||
int y_stride, uv_stride; // luma/chroma strides.
|
||||
uint8_t* a; // pointer to the alpha plane
|
||||
int a_stride; // stride of the alpha plane
|
||||
uint32_t pad1[2]; // padding for later use
|
||||
|
||||
// ARGB input (mostly used for input to lossless compression)
|
||||
uint32_t* argb; // Pointer to argb (32 bit) plane.
|
||||
int argb_stride; // This is stride in pixels units, not bytes.
|
||||
uint32_t pad2[3]; // padding for later use
|
||||
|
||||
// OUTPUT
|
||||
///////////////
|
||||
// Byte-emission hook, to store compressed bytes as they are ready.
|
||||
WebPWriterFunction writer; // can be NULL
|
||||
void* custom_ptr; // can be used by the writer.
|
||||
|
||||
// map for extra information (only for lossy compression mode)
|
||||
int extra_info_type; // 1: intra type, 2: segment, 3: quant
|
||||
// 4: intra-16 prediction mode,
|
||||
// 5: chroma prediction mode,
|
||||
// 6: bit cost, 7: distortion
|
||||
uint8_t* extra_info; // if not NULL, points to an array of size
|
||||
// ((width + 15) / 16) * ((height + 15) / 16) that
|
||||
// will be filled with a macroblock map, depending
|
||||
// on extra_info_type.
|
||||
|
||||
// STATS AND REPORTS
|
||||
///////////////////////////
|
||||
// Pointer to side statistics (updated only if not NULL)
|
||||
WebPAuxStats* stats;
|
||||
|
||||
// Error code for the latest error encountered during encoding
|
||||
WebPEncodingError error_code;
|
||||
|
||||
// If not NULL, report progress during encoding.
|
||||
WebPProgressHook progress_hook;
|
||||
|
||||
void* user_data; // this field is free to be set to any value and
|
||||
// used during callbacks (like progress-report e.g.).
|
||||
|
||||
uint32_t pad3[3]; // padding for later use
|
||||
|
||||
// Unused for now
|
||||
uint8_t* pad4, *pad5;
|
||||
uint32_t pad6[8]; // padding for later use
|
||||
|
||||
// PRIVATE FIELDS
|
||||
////////////////////
|
||||
void* memory_; // row chunk of memory for yuva planes
|
||||
void* memory_argb_; // and for argb too.
|
||||
void* pad7[2]; // padding for later use
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN int WebPPictureInitInternal(WebPPicture*, int);
|
||||
|
||||
// Should always be called, to initialize the structure. Returns false in case
|
||||
// of version mismatch. WebPPictureInit() must have succeeded before using the
|
||||
// 'picture' object.
|
||||
// Note that, by default, use_argb is false and colorspace is WEBP_YUV420.
|
||||
static WEBP_INLINE int WebPPictureInit(WebPPicture* picture) {
|
||||
return WebPPictureInitInternal(picture, WEBP_ENCODER_ABI_VERSION);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPPicture utils
|
||||
|
||||
// Convenience allocation / deallocation based on picture->width/height:
|
||||
// Allocate y/u/v buffers as per colorspace/width/height specification.
|
||||
// Note! This function will free the previous buffer if needed.
|
||||
// Returns false in case of memory error.
|
||||
WEBP_EXTERN int WebPPictureAlloc(WebPPicture* picture);
|
||||
|
||||
// Release the memory allocated by WebPPictureAlloc() or WebPPictureImport*().
|
||||
// Note that this function does _not_ free the memory used by the 'picture'
|
||||
// object itself.
|
||||
// Besides memory (which is reclaimed) all other fields of 'picture' are
|
||||
// preserved.
|
||||
WEBP_EXTERN void WebPPictureFree(WebPPicture* picture);
|
||||
|
||||
// Copy the pixels of *src into *dst, using WebPPictureAlloc. Upon return, *dst
|
||||
// will fully own the copied pixels (this is not a view). The 'dst' picture need
|
||||
// not be initialized as its content is overwritten.
|
||||
// Returns false in case of memory allocation error.
|
||||
WEBP_EXTERN int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst);
|
||||
|
||||
// Compute the single distortion for packed planes of samples.
|
||||
// 'src' will be compared to 'ref', and the raw distortion stored into
|
||||
// '*distortion'. The refined metric (log(MSE), log(1 - ssim),...' will be
|
||||
// stored in '*result'.
|
||||
// 'x_step' is the horizontal stride (in bytes) between samples.
|
||||
// 'src/ref_stride' is the byte distance between rows.
|
||||
// Returns false in case of error (bad parameter, memory allocation error, ...).
|
||||
WEBP_EXTERN int WebPPlaneDistortion(const uint8_t* src, size_t src_stride,
|
||||
const uint8_t* ref, size_t ref_stride,
|
||||
int width, int height,
|
||||
size_t x_step,
|
||||
int type, // 0 = PSNR, 1 = SSIM, 2 = LSIM
|
||||
float* distortion, float* result);
|
||||
|
||||
// Compute PSNR, SSIM or LSIM distortion metric between two pictures. Results
|
||||
// are in dB, stored in result[] in the B/G/R/A/All order. The distortion is
|
||||
// always performed using ARGB samples. Hence if the input is YUV(A), the
|
||||
// picture will be internally converted to ARGB (just for the measurement).
|
||||
// Warning: this function is rather CPU-intensive.
|
||||
WEBP_EXTERN int WebPPictureDistortion(
|
||||
const WebPPicture* src, const WebPPicture* ref,
|
||||
int metric_type, // 0 = PSNR, 1 = SSIM, 2 = LSIM
|
||||
float result[5]);
|
||||
|
||||
// self-crops a picture to the rectangle defined by top/left/width/height.
|
||||
// Returns false in case of memory allocation error, or if the rectangle is
|
||||
// outside of the source picture.
|
||||
// The rectangle for the view is defined by the top-left corner pixel
|
||||
// coordinates (left, top) as well as its width and height. This rectangle
|
||||
// must be fully be comprised inside the 'src' source picture. If the source
|
||||
// picture uses the YUV420 colorspace, the top and left coordinates will be
|
||||
// snapped to even values.
|
||||
WEBP_EXTERN int WebPPictureCrop(WebPPicture* picture,
|
||||
int left, int top, int width, int height);
|
||||
|
||||
// Extracts a view from 'src' picture into 'dst'. The rectangle for the view
|
||||
// is defined by the top-left corner pixel coordinates (left, top) as well
|
||||
// as its width and height. This rectangle must be fully be comprised inside
|
||||
// the 'src' source picture. If the source picture uses the YUV420 colorspace,
|
||||
// the top and left coordinates will be snapped to even values.
|
||||
// Picture 'src' must out-live 'dst' picture. Self-extraction of view is allowed
|
||||
// ('src' equal to 'dst') as a mean of fast-cropping (but note that doing so,
|
||||
// the original dimension will be lost). Picture 'dst' need not be initialized
|
||||
// with WebPPictureInit() if it is different from 'src', since its content will
|
||||
// be overwritten.
|
||||
// Returns false in case of invalid parameters.
|
||||
WEBP_EXTERN int WebPPictureView(const WebPPicture* src,
|
||||
int left, int top, int width, int height,
|
||||
WebPPicture* dst);
|
||||
|
||||
// Returns true if the 'picture' is actually a view and therefore does
|
||||
// not own the memory for pixels.
|
||||
WEBP_EXTERN int WebPPictureIsView(const WebPPicture* picture);
|
||||
|
||||
// Rescale a picture to new dimension width x height.
|
||||
// If either 'width' or 'height' (but not both) is 0 the corresponding
|
||||
// dimension will be calculated preserving the aspect ratio.
|
||||
// No gamma correction is applied.
|
||||
// Returns false in case of error (invalid parameter or insufficient memory).
|
||||
WEBP_EXTERN int WebPPictureRescale(WebPPicture* picture, int width, int height);
|
||||
|
||||
// Colorspace conversion function to import RGB samples.
|
||||
// Previous buffer will be free'd, if any.
|
||||
// *rgb buffer should have a size of at least height * rgb_stride.
|
||||
// Returns false in case of memory error.
|
||||
WEBP_EXTERN int WebPPictureImportRGB(
|
||||
WebPPicture* picture, const uint8_t* rgb, int rgb_stride);
|
||||
// Same, but for RGBA buffer.
|
||||
WEBP_EXTERN int WebPPictureImportRGBA(
|
||||
WebPPicture* picture, const uint8_t* rgba, int rgba_stride);
|
||||
// Same, but for RGBA buffer. Imports the RGB direct from the 32-bit format
|
||||
// input buffer ignoring the alpha channel. Avoids needing to copy the data
|
||||
// to a temporary 24-bit RGB buffer to import the RGB only.
|
||||
WEBP_EXTERN int WebPPictureImportRGBX(
|
||||
WebPPicture* picture, const uint8_t* rgbx, int rgbx_stride);
|
||||
|
||||
// Variants of the above, but taking BGR(A|X) input.
|
||||
WEBP_EXTERN int WebPPictureImportBGR(
|
||||
WebPPicture* picture, const uint8_t* bgr, int bgr_stride);
|
||||
WEBP_EXTERN int WebPPictureImportBGRA(
|
||||
WebPPicture* picture, const uint8_t* bgra, int bgra_stride);
|
||||
WEBP_EXTERN int WebPPictureImportBGRX(
|
||||
WebPPicture* picture, const uint8_t* bgrx, int bgrx_stride);
|
||||
|
||||
// Converts picture->argb data to the YUV420A format. The 'colorspace'
|
||||
// parameter is deprecated and should be equal to WEBP_YUV420.
|
||||
// Upon return, picture->use_argb is set to false. The presence of real
|
||||
// non-opaque transparent values is detected, and 'colorspace' will be
|
||||
// adjusted accordingly. Note that this method is lossy.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureARGBToYUVA(WebPPicture* picture,
|
||||
WebPEncCSP /*colorspace = WEBP_YUV420*/);
|
||||
|
||||
// Same as WebPPictureARGBToYUVA(), but the conversion is done using
|
||||
// pseudo-random dithering with a strength 'dithering' between
|
||||
// 0.0 (no dithering) and 1.0 (maximum dithering). This is useful
|
||||
// for photographic picture.
|
||||
WEBP_EXTERN int WebPPictureARGBToYUVADithered(
|
||||
WebPPicture* picture, WebPEncCSP colorspace, float dithering);
|
||||
|
||||
// Performs 'sharp' RGBA->YUVA420 downsampling and colorspace conversion.
|
||||
// Downsampling is handled with extra care in case of color clipping. This
|
||||
// method is roughly 2x slower than WebPPictureARGBToYUVA() but produces better
|
||||
// and sharper YUV representation.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureSharpARGBToYUVA(WebPPicture* picture);
|
||||
// kept for backward compatibility:
|
||||
WEBP_EXTERN int WebPPictureSmartARGBToYUVA(WebPPicture* picture);
|
||||
|
||||
// Converts picture->yuv to picture->argb and sets picture->use_argb to true.
|
||||
// The input format must be YUV_420 or YUV_420A. The conversion from YUV420 to
|
||||
// ARGB incurs a small loss too.
|
||||
// Note that the use of this colorspace is discouraged if one has access to the
|
||||
// raw ARGB samples, since using YUV420 is comparatively lossy.
|
||||
// Returns false in case of error.
|
||||
WEBP_EXTERN int WebPPictureYUVAToARGB(WebPPicture* picture);
|
||||
|
||||
// Helper function: given a width x height plane of RGBA or YUV(A) samples
|
||||
// clean-up or smoothen the YUV or RGB samples under fully transparent area,
|
||||
// to help compressibility (no guarantee, though).
|
||||
WEBP_EXTERN void WebPCleanupTransparentArea(WebPPicture* picture);
|
||||
|
||||
// Scan the picture 'picture' for the presence of non fully opaque alpha values.
|
||||
// Returns true in such case. Otherwise returns false (indicating that the
|
||||
// alpha plane can be ignored altogether e.g.).
|
||||
WEBP_EXTERN int WebPPictureHasTransparency(const WebPPicture* picture);
|
||||
|
||||
// Remove the transparency information (if present) by blending the color with
|
||||
// the background color 'background_rgb' (specified as 24bit RGB triplet).
|
||||
// After this call, all alpha values are reset to 0xff.
|
||||
WEBP_EXTERN void WebPBlendAlpha(WebPPicture* picture, uint32_t background_rgb);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Main call
|
||||
|
||||
// Main encoding call, after config and picture have been initialized.
|
||||
// 'picture' must be less than 16384x16384 in dimension (cf WEBP_MAX_DIMENSION),
|
||||
// and the 'config' object must be a valid one.
|
||||
// Returns false in case of error, true otherwise.
|
||||
// In case of error, picture->error_code is updated accordingly.
|
||||
// 'picture' can hold the source samples in both YUV(A) or ARGB input, depending
|
||||
// on the value of 'picture->use_argb'. It is highly recommended to use
|
||||
// the former for lossy encoding, and the latter for lossless encoding
|
||||
// (when config.lossless is true). Automatic conversion from one format to
|
||||
// another is provided but they both incur some loss.
|
||||
WEBP_EXTERN int WebPEncode(const WebPConfig* config, WebPPicture* picture);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_ENCODE_H_
|
||||
@@ -0,0 +1,530 @@
|
||||
// Copyright 2011 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// RIFF container manipulation and encoding for WebP images.
|
||||
//
|
||||
// Authors: Urvang (urvang@google.com)
|
||||
// Vikas (vikasa@google.com)
|
||||
|
||||
#ifndef WEBP_WEBP_MUX_H_
|
||||
#define WEBP_WEBP_MUX_H_
|
||||
|
||||
#include "./mux_types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
#define WEBP_MUX_ABI_VERSION 0x0108 // MAJOR(8b) + MINOR(8b)
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Mux API
|
||||
//
|
||||
// This API allows manipulation of WebP container images containing features
|
||||
// like color profile, metadata, animation.
|
||||
//
|
||||
// Code Example#1: Create a WebPMux object with image data, color profile and
|
||||
// XMP metadata.
|
||||
/*
|
||||
int copy_data = 0;
|
||||
WebPMux* mux = WebPMuxNew();
|
||||
// ... (Prepare image data).
|
||||
WebPMuxSetImage(mux, &image, copy_data);
|
||||
// ... (Prepare ICCP color profile data).
|
||||
WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
|
||||
// ... (Prepare XMP metadata).
|
||||
WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
|
||||
// Get data from mux in WebP RIFF format.
|
||||
WebPMuxAssemble(mux, &output_data);
|
||||
WebPMuxDelete(mux);
|
||||
// ... (Consume output_data; e.g. write output_data.bytes to file).
|
||||
WebPDataClear(&output_data);
|
||||
*/
|
||||
|
||||
// Code Example#2: Get image and color profile data from a WebP file.
|
||||
/*
|
||||
int copy_data = 0;
|
||||
// ... (Read data from file).
|
||||
WebPMux* mux = WebPMuxCreate(&data, copy_data);
|
||||
WebPMuxGetFrame(mux, 1, &image);
|
||||
// ... (Consume image; e.g. call WebPDecode() to decode the data).
|
||||
WebPMuxGetChunk(mux, "ICCP", &icc_profile);
|
||||
// ... (Consume icc_data).
|
||||
WebPMuxDelete(mux);
|
||||
WebPFree(data);
|
||||
*/
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPMuxError WebPMuxError;
|
||||
// typedef enum WebPChunkId WebPChunkId;
|
||||
typedef struct WebPMux WebPMux; // main opaque object.
|
||||
typedef struct WebPMuxFrameInfo WebPMuxFrameInfo;
|
||||
typedef struct WebPMuxAnimParams WebPMuxAnimParams;
|
||||
typedef struct WebPAnimEncoderOptions WebPAnimEncoderOptions;
|
||||
|
||||
// Error codes
|
||||
typedef enum WebPMuxError {
|
||||
WEBP_MUX_OK = 1,
|
||||
WEBP_MUX_NOT_FOUND = 0,
|
||||
WEBP_MUX_INVALID_ARGUMENT = -1,
|
||||
WEBP_MUX_BAD_DATA = -2,
|
||||
WEBP_MUX_MEMORY_ERROR = -3,
|
||||
WEBP_MUX_NOT_ENOUGH_DATA = -4
|
||||
} WebPMuxError;
|
||||
|
||||
// IDs for different types of chunks.
|
||||
typedef enum WebPChunkId {
|
||||
WEBP_CHUNK_VP8X, // VP8X
|
||||
WEBP_CHUNK_ICCP, // ICCP
|
||||
WEBP_CHUNK_ANIM, // ANIM
|
||||
WEBP_CHUNK_ANMF, // ANMF
|
||||
WEBP_CHUNK_DEPRECATED, // (deprecated from FRGM)
|
||||
WEBP_CHUNK_ALPHA, // ALPH
|
||||
WEBP_CHUNK_IMAGE, // VP8/VP8L
|
||||
WEBP_CHUNK_EXIF, // EXIF
|
||||
WEBP_CHUNK_XMP, // XMP
|
||||
WEBP_CHUNK_UNKNOWN, // Other chunks.
|
||||
WEBP_CHUNK_NIL
|
||||
} WebPChunkId;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// Returns the version number of the mux library, packed in hexadecimal using
|
||||
// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
|
||||
WEBP_EXTERN int WebPGetMuxVersion(void);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Life of a Mux object
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPMux* WebPNewInternal(int);
|
||||
|
||||
// Creates an empty mux object.
|
||||
// Returns:
|
||||
// A pointer to the newly created empty mux object.
|
||||
// Or NULL in case of memory error.
|
||||
static WEBP_INLINE WebPMux* WebPMuxNew(void) {
|
||||
return WebPNewInternal(WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Deletes the mux object.
|
||||
// Parameters:
|
||||
// mux - (in/out) object to be deleted
|
||||
WEBP_EXTERN void WebPMuxDelete(WebPMux* mux);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Mux creation.
|
||||
|
||||
// Internal, version-checked, entry point
|
||||
WEBP_EXTERN WebPMux* WebPMuxCreateInternal(const WebPData*, int, int);
|
||||
|
||||
// Creates a mux object from raw data given in WebP RIFF format.
|
||||
// Parameters:
|
||||
// bitstream - (in) the bitstream data in WebP RIFF format
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// A pointer to the mux object created from given data - on success.
|
||||
// NULL - In case of invalid data or memory error.
|
||||
static WEBP_INLINE WebPMux* WebPMuxCreate(const WebPData* bitstream,
|
||||
int copy_data) {
|
||||
return WebPMuxCreateInternal(bitstream, copy_data, WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Non-image chunks.
|
||||
|
||||
// Note: Only non-image related chunks should be managed through chunk APIs.
|
||||
// (Image related chunks are: "ANMF", "VP8 ", "VP8L" and "ALPH").
|
||||
// To add, get and delete images, use WebPMuxSetImage(), WebPMuxPushFrame(),
|
||||
// WebPMuxGetFrame() and WebPMuxDeleteFrame().
|
||||
|
||||
// Adds a chunk with id 'fourcc' and data 'chunk_data' in the mux object.
|
||||
// Any existing chunk(s) with the same id will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object to which the chunk is to be added
|
||||
// fourcc - (in) a character array containing the fourcc of the given chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// chunk_data - (in) the chunk data to be added
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetChunk(
|
||||
WebPMux* mux, const char fourcc[4], const WebPData* chunk_data,
|
||||
int copy_data);
|
||||
|
||||
// Gets a reference to the data of the chunk with id 'fourcc' in the mux object.
|
||||
// The caller should NOT free the returned data.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the chunk data is to be fetched
|
||||
// fourcc - (in) a character array containing the fourcc of the chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// chunk_data - (out) returned chunk data
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given id.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetChunk(
|
||||
const WebPMux* mux, const char fourcc[4], WebPData* chunk_data);
|
||||
|
||||
// Deletes the chunk with the given 'fourcc' from the mux object.
|
||||
// Parameters:
|
||||
// mux - (in/out) object from which the chunk is to be deleted
|
||||
// fourcc - (in) a character array containing the fourcc of the chunk;
|
||||
// e.g., "ICCP", "XMP ", "EXIF" etc.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or fourcc is NULL
|
||||
// or if fourcc corresponds to an image chunk.
|
||||
// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given fourcc.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxDeleteChunk(
|
||||
WebPMux* mux, const char fourcc[4]);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Images.
|
||||
|
||||
// Encapsulates data about a single frame.
|
||||
struct WebPMuxFrameInfo {
|
||||
WebPData bitstream; // image data: can be a raw VP8/VP8L bitstream
|
||||
// or a single-image WebP file.
|
||||
int x_offset; // x-offset of the frame.
|
||||
int y_offset; // y-offset of the frame.
|
||||
int duration; // duration of the frame (in milliseconds).
|
||||
|
||||
WebPChunkId id; // frame type: should be one of WEBP_CHUNK_ANMF
|
||||
// or WEBP_CHUNK_IMAGE
|
||||
WebPMuxAnimDispose dispose_method; // Disposal method for the frame.
|
||||
WebPMuxAnimBlend blend_method; // Blend operation for the frame.
|
||||
uint32_t pad[1]; // padding for later use
|
||||
};
|
||||
|
||||
// Sets the (non-animated) image in the mux object.
|
||||
// Note: Any existing images (including frames) will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object in which the image is to be set
|
||||
// bitstream - (in) can be a raw VP8/VP8L bitstream or a single-image
|
||||
// WebP file (non-animated)
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL or bitstream is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetImage(
|
||||
WebPMux* mux, const WebPData* bitstream, int copy_data);
|
||||
|
||||
// Adds a frame at the end of the mux object.
|
||||
// Notes: (1) frame.id should be WEBP_CHUNK_ANMF
|
||||
// (2) For setting a non-animated image, use WebPMuxSetImage() instead.
|
||||
// (3) Type of frame being pushed must be same as the frames in mux.
|
||||
// (4) As WebP only supports even offsets, any odd offset will be snapped
|
||||
// to an even location using: offset &= ~1
|
||||
// Parameters:
|
||||
// mux - (in/out) object to which the frame is to be added
|
||||
// frame - (in) frame data.
|
||||
// copy_data - (in) value 1 indicates given data WILL be copied to the mux
|
||||
// object and value 0 indicates data will NOT be copied.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL
|
||||
// or if content of 'frame' is invalid.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxPushFrame(
|
||||
WebPMux* mux, const WebPMuxFrameInfo* frame, int copy_data);
|
||||
|
||||
// Gets the nth frame from the mux object.
|
||||
// The content of 'frame->bitstream' is allocated using WebPMalloc(), and NOT
|
||||
// owned by the 'mux' object. It MUST be deallocated by the caller by calling
|
||||
// WebPDataClear().
|
||||
// nth=0 has a special meaning - last position.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the info is to be fetched
|
||||
// nth - (in) index of the frame in the mux object
|
||||
// frame - (out) data of the returned frame
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - if there are less than nth frames in the mux object.
|
||||
// WEBP_MUX_BAD_DATA - if nth frame chunk in mux is invalid.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetFrame(
|
||||
const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame);
|
||||
|
||||
// Deletes a frame from the mux object.
|
||||
// nth=0 has a special meaning - last position.
|
||||
// Parameters:
|
||||
// mux - (in/out) object from which a frame is to be deleted
|
||||
// nth - (in) The position from which the frame is to be deleted
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - If there are less than nth frames in the mux object
|
||||
// before deletion.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxDeleteFrame(WebPMux* mux, uint32_t nth);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Animation.
|
||||
|
||||
// Animation parameters.
|
||||
struct WebPMuxAnimParams {
|
||||
uint32_t bgcolor; // Background color of the canvas stored (in MSB order) as:
|
||||
// Bits 00 to 07: Alpha.
|
||||
// Bits 08 to 15: Red.
|
||||
// Bits 16 to 23: Green.
|
||||
// Bits 24 to 31: Blue.
|
||||
int loop_count; // Number of times to repeat the animation [0 = infinite].
|
||||
};
|
||||
|
||||
// Sets the animation parameters in the mux object. Any existing ANIM chunks
|
||||
// will be removed.
|
||||
// Parameters:
|
||||
// mux - (in/out) object in which ANIM chunk is to be set/added
|
||||
// params - (in) animation parameters.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetAnimationParams(
|
||||
WebPMux* mux, const WebPMuxAnimParams* params);
|
||||
|
||||
// Gets the animation parameters from the mux object.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the animation parameters to be fetched
|
||||
// params - (out) animation parameters extracted from the ANIM chunk
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
|
||||
// WEBP_MUX_NOT_FOUND - if ANIM chunk is not present in mux object.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetAnimationParams(
|
||||
const WebPMux* mux, WebPMuxAnimParams* params);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// Misc Utilities.
|
||||
|
||||
// Sets the canvas size for the mux object. The width and height can be
|
||||
// specified explicitly or left as zero (0, 0).
|
||||
// * When width and height are specified explicitly, then this frame bound is
|
||||
// enforced during subsequent calls to WebPMuxAssemble() and an error is
|
||||
// reported if any animated frame does not completely fit within the canvas.
|
||||
// * When unspecified (0, 0), the constructed canvas will get the frame bounds
|
||||
// from the bounding-box over all frames after calling WebPMuxAssemble().
|
||||
// Parameters:
|
||||
// mux - (in) object to which the canvas size is to be set
|
||||
// width - (in) canvas width
|
||||
// height - (in) canvas height
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL; or
|
||||
// width or height are invalid or out of bounds
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxSetCanvasSize(WebPMux* mux,
|
||||
int width, int height);
|
||||
|
||||
// Gets the canvas size from the mux object.
|
||||
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
|
||||
// That is, the mux object hasn't been modified since the last call to
|
||||
// WebPMuxAssemble() or WebPMuxCreate().
|
||||
// Parameters:
|
||||
// mux - (in) object from which the canvas size is to be fetched
|
||||
// width - (out) canvas width
|
||||
// height - (out) canvas height
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, width or height is NULL.
|
||||
// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetCanvasSize(const WebPMux* mux,
|
||||
int* width, int* height);
|
||||
|
||||
// Gets the feature flags from the mux object.
|
||||
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
|
||||
// That is, the mux object hasn't been modified since the last call to
|
||||
// WebPMuxAssemble() or WebPMuxCreate().
|
||||
// Parameters:
|
||||
// mux - (in) object from which the features are to be fetched
|
||||
// flags - (out) the flags specifying which features are present in the
|
||||
// mux object. This will be an OR of various flag values.
|
||||
// Enum 'WebPFeatureFlags' can be used to test individual flag values.
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or flags is NULL.
|
||||
// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxGetFeatures(const WebPMux* mux,
|
||||
uint32_t* flags);
|
||||
|
||||
// Gets number of chunks with the given 'id' in the mux object.
|
||||
// Parameters:
|
||||
// mux - (in) object from which the info is to be fetched
|
||||
// id - (in) chunk id specifying the type of chunk
|
||||
// num_elements - (out) number of chunks with the given chunk id
|
||||
// Returns:
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux, or num_elements is NULL.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxNumChunks(const WebPMux* mux,
|
||||
WebPChunkId id, int* num_elements);
|
||||
|
||||
// Assembles all chunks in WebP RIFF format and returns in 'assembled_data'.
|
||||
// This function also validates the mux object.
|
||||
// Note: The content of 'assembled_data' will be ignored and overwritten.
|
||||
// Also, the content of 'assembled_data' is allocated using WebPMalloc(), and
|
||||
// NOT owned by the 'mux' object. It MUST be deallocated by the caller by
|
||||
// calling WebPDataClear(). It's always safe to call WebPDataClear() upon
|
||||
// return, even in case of error.
|
||||
// Parameters:
|
||||
// mux - (in/out) object whose chunks are to be assembled
|
||||
// assembled_data - (out) assembled WebP data
|
||||
// Returns:
|
||||
// WEBP_MUX_BAD_DATA - if mux object is invalid.
|
||||
// WEBP_MUX_INVALID_ARGUMENT - if mux or assembled_data is NULL.
|
||||
// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
|
||||
// WEBP_MUX_OK - on success.
|
||||
WEBP_EXTERN WebPMuxError WebPMuxAssemble(WebPMux* mux,
|
||||
WebPData* assembled_data);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// WebPAnimEncoder API
|
||||
//
|
||||
// This API allows encoding (possibly) animated WebP images.
|
||||
//
|
||||
// Code Example:
|
||||
/*
|
||||
WebPAnimEncoderOptions enc_options;
|
||||
WebPAnimEncoderOptionsInit(&enc_options);
|
||||
// Tune 'enc_options' as needed.
|
||||
WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
|
||||
while(<there are more frames>) {
|
||||
WebPConfig config;
|
||||
WebPConfigInit(&config);
|
||||
// Tune 'config' as needed.
|
||||
WebPAnimEncoderAdd(enc, frame, timestamp_ms, &config);
|
||||
}
|
||||
WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
|
||||
WebPAnimEncoderAssemble(enc, webp_data);
|
||||
WebPAnimEncoderDelete(enc);
|
||||
// Write the 'webp_data' to a file, or re-mux it further.
|
||||
*/
|
||||
|
||||
typedef struct WebPAnimEncoder WebPAnimEncoder; // Main opaque object.
|
||||
|
||||
// Forward declarations. Defined in encode.h.
|
||||
struct WebPPicture;
|
||||
struct WebPConfig;
|
||||
|
||||
// Global options.
|
||||
struct WebPAnimEncoderOptions {
|
||||
WebPMuxAnimParams anim_params; // Animation parameters.
|
||||
int minimize_size; // If true, minimize the output size (slow). Implicitly
|
||||
// disables key-frame insertion.
|
||||
int kmin;
|
||||
int kmax; // Minimum and maximum distance between consecutive key
|
||||
// frames in the output. The library may insert some key
|
||||
// frames as needed to satisfy this criteria.
|
||||
// Note that these conditions should hold: kmax > kmin
|
||||
// and kmin >= kmax / 2 + 1. Also, if kmax <= 0, then
|
||||
// key-frame insertion is disabled; and if kmax == 1,
|
||||
// then all frames will be key-frames (kmin value does
|
||||
// not matter for these special cases).
|
||||
int allow_mixed; // If true, use mixed compression mode; may choose
|
||||
// either lossy and lossless for each frame.
|
||||
int verbose; // If true, print info and warning messages to stderr.
|
||||
|
||||
uint32_t padding[4]; // Padding for later use.
|
||||
};
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN int WebPAnimEncoderOptionsInitInternal(
|
||||
WebPAnimEncoderOptions*, int);
|
||||
|
||||
// Should always be called, to initialize a fresh WebPAnimEncoderOptions
|
||||
// structure before modification. Returns false in case of version mismatch.
|
||||
// WebPAnimEncoderOptionsInit() must have succeeded before using the
|
||||
// 'enc_options' object.
|
||||
static WEBP_INLINE int WebPAnimEncoderOptionsInit(
|
||||
WebPAnimEncoderOptions* enc_options) {
|
||||
return WebPAnimEncoderOptionsInitInternal(enc_options, WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Internal, version-checked, entry point.
|
||||
WEBP_EXTERN WebPAnimEncoder* WebPAnimEncoderNewInternal(
|
||||
int, int, const WebPAnimEncoderOptions*, int);
|
||||
|
||||
// Creates and initializes a WebPAnimEncoder object.
|
||||
// Parameters:
|
||||
// width/height - (in) canvas width and height of the animation.
|
||||
// enc_options - (in) encoding options; can be passed NULL to pick
|
||||
// reasonable defaults.
|
||||
// Returns:
|
||||
// A pointer to the newly created WebPAnimEncoder object.
|
||||
// Or NULL in case of memory error.
|
||||
static WEBP_INLINE WebPAnimEncoder* WebPAnimEncoderNew(
|
||||
int width, int height, const WebPAnimEncoderOptions* enc_options) {
|
||||
return WebPAnimEncoderNewInternal(width, height, enc_options,
|
||||
WEBP_MUX_ABI_VERSION);
|
||||
}
|
||||
|
||||
// Optimize the given frame for WebP, encode it and add it to the
|
||||
// WebPAnimEncoder object.
|
||||
// The last call to 'WebPAnimEncoderAdd' should be with frame = NULL, which
|
||||
// indicates that no more frames are to be added. This call is also used to
|
||||
// determine the duration of the last frame.
|
||||
// Parameters:
|
||||
// enc - (in/out) object to which the frame is to be added.
|
||||
// frame - (in/out) frame data in ARGB or YUV(A) format. If it is in YUV(A)
|
||||
// format, it will be converted to ARGB, which incurs a small loss.
|
||||
// timestamp_ms - (in) timestamp of this frame in milliseconds.
|
||||
// Duration of a frame would be calculated as
|
||||
// "timestamp of next frame - timestamp of this frame".
|
||||
// Hence, timestamps should be in non-decreasing order.
|
||||
// config - (in) encoding options; can be passed NULL to pick
|
||||
// reasonable defaults.
|
||||
// Returns:
|
||||
// On error, returns false and frame->error_code is set appropriately.
|
||||
// Otherwise, returns true.
|
||||
WEBP_EXTERN int WebPAnimEncoderAdd(
|
||||
WebPAnimEncoder* enc, struct WebPPicture* frame, int timestamp_ms,
|
||||
const struct WebPConfig* config);
|
||||
|
||||
// Assemble all frames added so far into a WebP bitstream.
|
||||
// This call should be preceded by a call to 'WebPAnimEncoderAdd' with
|
||||
// frame = NULL; if not, the duration of the last frame will be internally
|
||||
// estimated.
|
||||
// Parameters:
|
||||
// enc - (in/out) object from which the frames are to be assembled.
|
||||
// webp_data - (out) generated WebP bitstream.
|
||||
// Returns:
|
||||
// True on success.
|
||||
WEBP_EXTERN int WebPAnimEncoderAssemble(WebPAnimEncoder* enc,
|
||||
WebPData* webp_data);
|
||||
|
||||
// Get error string corresponding to the most recent call using 'enc'. The
|
||||
// returned string is owned by 'enc' and is valid only until the next call to
|
||||
// WebPAnimEncoderAdd() or WebPAnimEncoderAssemble() or WebPAnimEncoderDelete().
|
||||
// Parameters:
|
||||
// enc - (in/out) object from which the error string is to be fetched.
|
||||
// Returns:
|
||||
// NULL if 'enc' is NULL. Otherwise, returns the error string if the last call
|
||||
// to 'enc' had an error, or an empty string if the last call was a success.
|
||||
WEBP_EXTERN const char* WebPAnimEncoderGetError(WebPAnimEncoder* enc);
|
||||
|
||||
// Deletes the WebPAnimEncoder object.
|
||||
// Parameters:
|
||||
// enc - (in/out) object to be deleted
|
||||
WEBP_EXTERN void WebPAnimEncoderDelete(WebPAnimEncoder* enc);
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_MUX_H_
|
||||
@@ -0,0 +1,98 @@
|
||||
// Copyright 2012 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Data-types common to the mux and demux libraries.
|
||||
//
|
||||
// Author: Urvang (urvang@google.com)
|
||||
|
||||
#ifndef WEBP_WEBP_MUX_TYPES_H_
|
||||
#define WEBP_WEBP_MUX_TYPES_H_
|
||||
|
||||
#include <string.h> // memset()
|
||||
#include "./types.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
// Note: forward declaring enumerations is not allowed in (strict) C and C++,
|
||||
// the types are left here for reference.
|
||||
// typedef enum WebPFeatureFlags WebPFeatureFlags;
|
||||
// typedef enum WebPMuxAnimDispose WebPMuxAnimDispose;
|
||||
// typedef enum WebPMuxAnimBlend WebPMuxAnimBlend;
|
||||
typedef struct WebPData WebPData;
|
||||
|
||||
// VP8X Feature Flags.
|
||||
typedef enum WebPFeatureFlags {
|
||||
ANIMATION_FLAG = 0x00000002,
|
||||
XMP_FLAG = 0x00000004,
|
||||
EXIF_FLAG = 0x00000008,
|
||||
ALPHA_FLAG = 0x00000010,
|
||||
ICCP_FLAG = 0x00000020,
|
||||
|
||||
ALL_VALID_FLAGS = 0x0000003e
|
||||
} WebPFeatureFlags;
|
||||
|
||||
// Dispose method (animation only). Indicates how the area used by the current
|
||||
// frame is to be treated before rendering the next frame on the canvas.
|
||||
typedef enum WebPMuxAnimDispose {
|
||||
WEBP_MUX_DISPOSE_NONE, // Do not dispose.
|
||||
WEBP_MUX_DISPOSE_BACKGROUND // Dispose to background color.
|
||||
} WebPMuxAnimDispose;
|
||||
|
||||
// Blend operation (animation only). Indicates how transparent pixels of the
|
||||
// current frame are blended with those of the previous canvas.
|
||||
typedef enum WebPMuxAnimBlend {
|
||||
WEBP_MUX_BLEND, // Blend.
|
||||
WEBP_MUX_NO_BLEND // Do not blend.
|
||||
} WebPMuxAnimBlend;
|
||||
|
||||
// Data type used to describe 'raw' data, e.g., chunk data
|
||||
// (ICC profile, metadata) and WebP compressed image data.
|
||||
// 'bytes' memory must be allocated using WebPMalloc() and such.
|
||||
struct WebPData {
|
||||
const uint8_t* bytes;
|
||||
size_t size;
|
||||
};
|
||||
|
||||
// Initializes the contents of the 'webp_data' object with default values.
|
||||
static WEBP_INLINE void WebPDataInit(WebPData* webp_data) {
|
||||
if (webp_data != NULL) {
|
||||
memset(webp_data, 0, sizeof(*webp_data));
|
||||
}
|
||||
}
|
||||
|
||||
// Clears the contents of the 'webp_data' object by calling WebPFree().
|
||||
// Does not deallocate the object itself.
|
||||
static WEBP_INLINE void WebPDataClear(WebPData* webp_data) {
|
||||
if (webp_data != NULL) {
|
||||
WebPFree((void*)webp_data->bytes);
|
||||
WebPDataInit(webp_data);
|
||||
}
|
||||
}
|
||||
|
||||
// Allocates necessary storage for 'dst' and copies the contents of 'src'.
|
||||
// Returns true on success.
|
||||
static WEBP_INLINE int WebPDataCopy(const WebPData* src, WebPData* dst) {
|
||||
if (src == NULL || dst == NULL) return 0;
|
||||
WebPDataInit(dst);
|
||||
if (src->bytes != NULL && src->size != 0) {
|
||||
dst->bytes = (uint8_t*)WebPMalloc(src->size);
|
||||
if (dst->bytes == NULL) return 0;
|
||||
memcpy((void*)dst->bytes, src->bytes, src->size);
|
||||
dst->size = src->size;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_MUX_TYPES_H_
|
||||
@@ -0,0 +1,68 @@
|
||||
// Copyright 2010 Google Inc. All Rights Reserved.
|
||||
//
|
||||
// Use of this source code is governed by a BSD-style license
|
||||
// that can be found in the COPYING file in the root of the source
|
||||
// tree. An additional intellectual property rights grant can be found
|
||||
// in the file PATENTS. All contributing project authors may
|
||||
// be found in the AUTHORS file in the root of the source tree.
|
||||
// -----------------------------------------------------------------------------
|
||||
//
|
||||
// Common types + memory wrappers
|
||||
//
|
||||
// Author: Skal (pascal.massimino@gmail.com)
|
||||
|
||||
#ifndef WEBP_WEBP_TYPES_H_
|
||||
#define WEBP_WEBP_TYPES_H_
|
||||
|
||||
#include <stddef.h> // for size_t
|
||||
|
||||
#ifndef _MSC_VER
|
||||
#include <inttypes.h>
|
||||
#if defined(__cplusplus) || !defined(__STRICT_ANSI__) || \
|
||||
(defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L)
|
||||
#define WEBP_INLINE inline
|
||||
#else
|
||||
#define WEBP_INLINE
|
||||
#endif
|
||||
#else
|
||||
typedef signed char int8_t;
|
||||
typedef unsigned char uint8_t;
|
||||
typedef signed short int16_t;
|
||||
typedef unsigned short uint16_t;
|
||||
typedef signed int int32_t;
|
||||
typedef unsigned int uint32_t;
|
||||
typedef unsigned long long int uint64_t;
|
||||
typedef long long int int64_t;
|
||||
#define WEBP_INLINE __forceinline
|
||||
#endif /* _MSC_VER */
|
||||
|
||||
#ifndef WEBP_EXTERN
|
||||
// This explicitly marks library functions and allows for changing the
|
||||
// signature for e.g., Windows DLL builds.
|
||||
# if defined(__GNUC__) && __GNUC__ >= 4
|
||||
# define WEBP_EXTERN extern __attribute__ ((visibility ("default")))
|
||||
# else
|
||||
# define WEBP_EXTERN extern
|
||||
# endif /* __GNUC__ >= 4 */
|
||||
#endif /* WEBP_EXTERN */
|
||||
|
||||
// Macro to check ABI compatibility (same major revision number)
|
||||
#define WEBP_ABI_IS_INCOMPATIBLE(a, b) (((a) >> 8) != ((b) >> 8))
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
// Allocates 'size' bytes of memory. Returns NULL upon error. Memory
|
||||
// must be deallocated by calling WebPFree(). This function is made available
|
||||
// by the core 'libwebp' library.
|
||||
WEBP_EXTERN void* WebPMalloc(size_t size);
|
||||
|
||||
// Releases memory returned by the WebPDecode*() functions (from decode.h).
|
||||
WEBP_EXTERN void WebPFree(void* ptr);
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif
|
||||
|
||||
#endif // WEBP_WEBP_TYPES_H_
|
||||
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@@ -0,0 +1,29 @@
|
||||
# How to Contribute
|
||||
|
||||
We'd love to accept your patches and contributions to this project. There are
|
||||
just a few small guidelines you need to follow.
|
||||
|
||||
## Contributor License Agreement
|
||||
|
||||
Contributions to this project must be accompanied by a Contributor License
|
||||
Agreement. You (or your employer) retain the copyright to your contribution;
|
||||
this simply gives us permission to use and redistribute your contributions as
|
||||
part of the project. Head over to <https://cla.developers.google.com/> to see
|
||||
your current agreements on file or to sign a new one.
|
||||
|
||||
You generally only need to submit a CLA once, so if you've already submitted one
|
||||
(even if it was for a different project), you probably don't need to do it
|
||||
again.
|
||||
|
||||
## Code reviews
|
||||
|
||||
All submissions, including submissions by project members, require review. We
|
||||
use a [Gerrit](https://www.gerritcodereview.com) instance hosted at
|
||||
https://chromium-review.googlesource.com for this purpose. See the
|
||||
[WebM Project page](https://www.webmproject.org/code/contribute/submitting-patches/)
|
||||
for additional details.
|
||||
|
||||
## Community Guidelines
|
||||
|
||||
This project follows
|
||||
[Google's Open Source Community Guidelines](https://opensource.google.com/conduct/).
|
||||
@@ -0,0 +1,65 @@
|
||||
# WebP Codec
|
||||
|
||||
```
|
||||
__ __ ____ ____ ____
|
||||
/ \\/ \/ _ \/ _ )/ _ \
|
||||
\ / __/ _ \ __/
|
||||
\__\__/\____/\_____/__/ ____ ___
|
||||
/ _/ / \ \ / _ \/ _/
|
||||
/ \_/ / / \ \ __/ \__
|
||||
\____/____/\_____/_____/____/v1.2.4
|
||||
```
|
||||
|
||||
WebP codec is a library to encode and decode images in WebP format. This package
|
||||
contains the library that can be used in other programs to add WebP support, as
|
||||
well as the command line tools 'cwebp' and 'dwebp' to compress and decompress
|
||||
images respectively.
|
||||
|
||||
See https://developers.google.com/speed/webp for details on the image format.
|
||||
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp
|
||||
|
||||
It is released under the same license as the WebM project. See
|
||||
https://www.webmproject.org/license/software/ or the "COPYING" file for details.
|
||||
An additional intellectual property rights grant can be found in the file
|
||||
PATENTS.
|
||||
|
||||
## Files
|
||||
|
||||
* bin/cwebp : encoding tool
|
||||
* bin/dwebp : decoding tool
|
||||
* bin/gif2webp : gif conversion tool
|
||||
* bin/img2webp : animation creation tool
|
||||
* bin/vwebp : webp visualization tool
|
||||
* bin/webpinfo : webp analysis tool
|
||||
* bin/webpmux : webp muxing tool
|
||||
* bin/anim\_diff : webp file comparison tool
|
||||
* bin/anim\_dump : tool for dumping animation frames
|
||||
* bin/get\_disto : tool for calculating file distortion
|
||||
* bin/webp\_quality : webp quality estimation tool
|
||||
* doc/ : manual in HTML and text formats
|
||||
* lib/ : static libraries
|
||||
* include/webp : headers
|
||||
|
||||
## Encoding and Decoding Tools
|
||||
|
||||
The bin/ directory contains tools to encode and decode images and animations,
|
||||
view information about WebP images, and more. See the
|
||||
[tools documentation](doc/tools.md).
|
||||
|
||||
## APIs
|
||||
|
||||
See the [APIs documentation](doc/api.md).
|
||||
|
||||
## Bugs
|
||||
|
||||
Please report all bugs to the issue tracker: https://bugs.chromium.org/p/webp
|
||||
|
||||
Patches welcome! See [how to contribute](CONTRIBUTING.md).
|
||||
|
||||
## Discuss
|
||||
|
||||
Email: webp-discuss@webmproject.org
|
||||
|
||||
Web: https://groups.google.com/a/webmproject.org/group/webp-discuss
|
||||
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@@ -0,0 +1,385 @@
|
||||
# WebP APIs
|
||||
|
||||
## Encoding API
|
||||
|
||||
The main encoding functions are available in the header src/webp/encode.h
|
||||
|
||||
The ready-to-use ones are:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
size_t WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride,
|
||||
float quality_factor, uint8_t** output);
|
||||
```
|
||||
|
||||
They will convert raw RGB samples to a WebP data. The only control supplied is
|
||||
the quality factor.
|
||||
|
||||
There are some variants for using the lossless format:
|
||||
|
||||
```c
|
||||
size_t WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
size_t WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height,
|
||||
int stride, uint8_t** output);
|
||||
```
|
||||
|
||||
Of course in this case, no quality factor is needed since the compression occurs
|
||||
without loss of the input values, at the expense of larger output sizes.
|
||||
|
||||
### Advanced encoding API
|
||||
|
||||
A more advanced API is based on the WebPConfig and WebPPicture structures.
|
||||
|
||||
WebPConfig contains the encoding settings and is not tied to a particular
|
||||
picture. WebPPicture contains input data, on which some WebPConfig will be used
|
||||
for compression. The encoding flow looks like:
|
||||
|
||||
```c
|
||||
#include <webp/encode.h>
|
||||
|
||||
// Setup a config, starting form a preset and tuning some additional
|
||||
// parameters
|
||||
WebPConfig config;
|
||||
if (!WebPConfigPreset(&config, WEBP_PRESET_PHOTO, quality_factor)) {
|
||||
return 0; // version error
|
||||
}
|
||||
// ... additional tuning
|
||||
config.sns_strength = 90;
|
||||
config.filter_sharpness = 6;
|
||||
config_error = WebPValidateConfig(&config); // not mandatory, but useful
|
||||
|
||||
// Setup the input data
|
||||
WebPPicture pic;
|
||||
if (!WebPPictureInit(&pic)) {
|
||||
return 0; // version error
|
||||
}
|
||||
pic.width = width;
|
||||
pic.height = height;
|
||||
// allocated picture of dimension width x height
|
||||
if (!WebPPictureAlloc(&pic)) {
|
||||
return 0; // memory error
|
||||
}
|
||||
// at this point, 'pic' has been initialized as a container,
|
||||
// and can receive the Y/U/V samples.
|
||||
// Alternatively, one could use ready-made import functions like
|
||||
// WebPPictureImportRGB(), which will take care of memory allocation.
|
||||
// In any case, past this point, one will have to call
|
||||
// WebPPictureFree(&pic) to reclaim memory.
|
||||
|
||||
// Set up a byte-output write method. WebPMemoryWriter, for instance.
|
||||
WebPMemoryWriter wrt;
|
||||
WebPMemoryWriterInit(&wrt); // initialize 'wrt'
|
||||
|
||||
pic.writer = MyFileWriter;
|
||||
pic.custom_ptr = my_opaque_structure_to_make_MyFileWriter_work;
|
||||
|
||||
// Compress!
|
||||
int ok = WebPEncode(&config, &pic); // ok = 0 => error occurred!
|
||||
WebPPictureFree(&pic); // must be called independently of the 'ok' result.
|
||||
|
||||
// output data should have been handled by the writer at that point.
|
||||
// -> compressed data is the memory buffer described by wrt.mem / wrt.size
|
||||
|
||||
// deallocate the memory used by compressed data
|
||||
WebPMemoryWriterClear(&wrt);
|
||||
```
|
||||
|
||||
## Decoding API
|
||||
|
||||
This is mainly just one function to call:
|
||||
|
||||
```c
|
||||
#include "webp/decode.h"
|
||||
uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
Please have a look at the file src/webp/decode.h for the details. There are
|
||||
variants for decoding in BGR/RGBA/ARGB/BGRA order, along with decoding to raw
|
||||
Y'CbCr samples. One can also decode the image directly into a pre-allocated
|
||||
buffer.
|
||||
|
||||
To detect a WebP file and gather the picture's dimensions, the function:
|
||||
|
||||
```c
|
||||
int WebPGetInfo(const uint8_t* data, size_t data_size,
|
||||
int* width, int* height);
|
||||
```
|
||||
|
||||
is supplied. No decoding is involved when using it.
|
||||
|
||||
### Incremental decoding API
|
||||
|
||||
In the case when data is being progressively transmitted, pictures can still be
|
||||
incrementally decoded using a slightly more complicated API. Decoder state is
|
||||
stored into an instance of the WebPIDecoder object. This object can be created
|
||||
with the purpose of decoding either RGB or Y'CbCr samples. For instance:
|
||||
|
||||
```c
|
||||
WebPDecBuffer buffer;
|
||||
WebPInitDecBuffer(&buffer);
|
||||
buffer.colorspace = MODE_BGR;
|
||||
...
|
||||
WebPIDecoder* idec = WebPINewDecoder(&buffer);
|
||||
```
|
||||
|
||||
As data is made progressively available, this incremental-decoder object can be
|
||||
used to decode the picture further. There are two (mutually exclusive) ways to
|
||||
pass freshly arrived data:
|
||||
|
||||
either by appending the fresh bytes:
|
||||
|
||||
```c
|
||||
WebPIAppend(idec, fresh_data, size_of_fresh_data);
|
||||
```
|
||||
|
||||
or by just mentioning the new size of the transmitted data:
|
||||
|
||||
```c
|
||||
WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
|
||||
```
|
||||
|
||||
Note that 'buffer' can be modified between each call to WebPIUpdate, in
|
||||
particular when the buffer is resized to accommodate larger data.
|
||||
|
||||
These functions will return the decoding status: either VP8_STATUS_SUSPENDED if
|
||||
decoding is not finished yet or VP8_STATUS_OK when decoding is done. Any other
|
||||
status is an error condition.
|
||||
|
||||
The 'idec' object must always be released (even upon an error condition) by
|
||||
calling: WebPDelete(idec).
|
||||
|
||||
To retrieve partially decoded picture samples, one must use the corresponding
|
||||
method: WebPIDecGetRGB or WebPIDecGetYUVA. It will return the last displayable
|
||||
pixel row.
|
||||
|
||||
Lastly, note that decoding can also be performed into a pre-allocated pixel
|
||||
buffer. This buffer must be passed when creating a WebPIDecoder, calling
|
||||
WebPINewRGB() or WebPINewYUVA().
|
||||
|
||||
Please have a look at the src/webp/decode.h header for further details.
|
||||
|
||||
### Advanced Decoding API
|
||||
|
||||
WebP decoding supports an advanced API which provides on-the-fly cropping and
|
||||
rescaling, something of great usefulness on memory-constrained environments like
|
||||
mobile phones. Basically, the memory usage will scale with the output's size,
|
||||
not the input's, when one only needs a quick preview or a zoomed in portion of
|
||||
an otherwise too-large picture. Some CPU can be saved too, incidentally.
|
||||
|
||||
```c
|
||||
// A) Init a configuration object
|
||||
WebPDecoderConfig config;
|
||||
CHECK(WebPInitDecoderConfig(&config));
|
||||
|
||||
// B) optional: retrieve the bitstream's features.
|
||||
CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
|
||||
|
||||
// C) Adjust 'config' options, if needed
|
||||
config.options.no_fancy_upsampling = 1;
|
||||
config.options.use_scaling = 1;
|
||||
config.options.scaled_width = scaledWidth();
|
||||
config.options.scaled_height = scaledHeight();
|
||||
// etc.
|
||||
|
||||
// D) Specify 'config' output options for specifying output colorspace.
|
||||
// Optionally the external image decode buffer can also be specified.
|
||||
config.output.colorspace = MODE_BGRA;
|
||||
// Optionally, the config.output can be pointed to an external buffer as
|
||||
// well for decoding the image. This externally supplied memory buffer
|
||||
// should be big enough to store the decoded picture.
|
||||
config.output.u.RGBA.rgba = (uint8_t*) memory_buffer;
|
||||
config.output.u.RGBA.stride = scanline_stride;
|
||||
config.output.u.RGBA.size = total_size_of_the_memory_buffer;
|
||||
config.output.is_external_memory = 1;
|
||||
|
||||
// E) Decode the WebP image. There are two variants w.r.t decoding image.
|
||||
// The first one (E.1) decodes the full image and the second one (E.2) is
|
||||
// used to incrementally decode the image using small input buffers.
|
||||
// Any one of these steps can be used to decode the WebP image.
|
||||
|
||||
// E.1) Decode full image.
|
||||
CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
|
||||
|
||||
// E.2) Decode image incrementally.
|
||||
WebPIDecoder* const idec = WebPIDecode(NULL, NULL, &config);
|
||||
CHECK(idec != NULL);
|
||||
while (bytes_remaining > 0) {
|
||||
VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
|
||||
if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
|
||||
bytes_remaining -= bytes_read;
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
WebPIDelete(idec);
|
||||
|
||||
// F) Decoded image is now in config.output (and config.output.u.RGBA).
|
||||
// It can be saved, displayed or otherwise processed.
|
||||
|
||||
// G) Reclaim memory allocated in config's object. It's safe to call
|
||||
// this function even if the memory is external and wasn't allocated
|
||||
// by WebPDecode().
|
||||
WebPFreeDecBuffer(&config.output);
|
||||
```
|
||||
|
||||
## Webp Mux
|
||||
|
||||
WebPMux is a set of two libraries 'Mux' and 'Demux' for creation, extraction and
|
||||
manipulation of an extended format WebP file, which can have features like color
|
||||
profile, metadata and animation. Reference command-line tools `webpmux` and
|
||||
`vwebp` as well as the WebP container specification
|
||||
'doc/webp-container-spec.txt' are also provided in this package, see the
|
||||
[tools documentation](tools.md).
|
||||
|
||||
### Mux API
|
||||
|
||||
The Mux API contains methods for adding data to and reading data from WebP
|
||||
files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
|
||||
Other features may be added in subsequent releases.
|
||||
|
||||
Example#1 (pseudo code): Creating a WebPMux object with image data, color
|
||||
profile and XMP metadata.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
WebPMux* mux = WebPMuxNew();
|
||||
// ... (Prepare image data).
|
||||
WebPMuxSetImage(mux, &image, copy_data);
|
||||
// ... (Prepare ICC profile data).
|
||||
WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
|
||||
// ... (Prepare XMP metadata).
|
||||
WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
|
||||
// Get data from mux in WebP RIFF format.
|
||||
WebPMuxAssemble(mux, &output_data);
|
||||
WebPMuxDelete(mux);
|
||||
// ... (Consume output_data; e.g. write output_data.bytes to file).
|
||||
WebPDataClear(&output_data);
|
||||
```
|
||||
|
||||
Example#2 (pseudo code): Get image and color profile data from a WebP file.
|
||||
|
||||
```c
|
||||
int copy_data = 0;
|
||||
// ... (Read data from file).
|
||||
WebPMux* mux = WebPMuxCreate(&data, copy_data);
|
||||
WebPMuxGetFrame(mux, 1, &image);
|
||||
// ... (Consume image; e.g. call WebPDecode() to decode the data).
|
||||
WebPMuxGetChunk(mux, "ICCP", &icc_profile);
|
||||
// ... (Consume icc_profile).
|
||||
WebPMuxDelete(mux);
|
||||
free(data);
|
||||
```
|
||||
|
||||
For a detailed Mux API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
### Demux API
|
||||
|
||||
The Demux API enables extraction of images and extended format data from WebP
|
||||
files. This API currently supports reading of XMP/EXIF metadata, ICC profile and
|
||||
animated images. Other features may be added in subsequent releases.
|
||||
|
||||
Code example: Demuxing WebP data to extract all the frames, ICC profile and
|
||||
EXIF/XMP metadata.
|
||||
|
||||
```c
|
||||
WebPDemuxer* demux = WebPDemux(&webp_data);
|
||||
uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
|
||||
uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
|
||||
// ... (Get information about the features present in the WebP file).
|
||||
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
|
||||
|
||||
// ... (Iterate over all frames).
|
||||
WebPIterator iter;
|
||||
if (WebPDemuxGetFrame(demux, 1, &iter)) {
|
||||
do {
|
||||
// ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
|
||||
// ... and get other frame properties like width, height, offsets etc.
|
||||
// ... see 'struct WebPIterator' below for more info).
|
||||
} while (WebPDemuxNextFrame(&iter));
|
||||
WebPDemuxReleaseIterator(&iter);
|
||||
}
|
||||
|
||||
// ... (Extract metadata).
|
||||
WebPChunkIterator chunk_iter;
|
||||
if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
|
||||
// ... (Consume the ICC profile in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
|
||||
// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
|
||||
// ... (Consume the XMP metadata in 'chunk_iter.chunk').
|
||||
WebPDemuxReleaseChunkIterator(&chunk_iter);
|
||||
WebPDemuxDelete(demux);
|
||||
```
|
||||
|
||||
For a detailed Demux API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
|
||||
## AnimEncoder API
|
||||
|
||||
The AnimEncoder API can be used to create animated WebP images.
|
||||
|
||||
Code example:
|
||||
|
||||
```c
|
||||
WebPAnimEncoderOptions enc_options;
|
||||
WebPAnimEncoderOptionsInit(&enc_options);
|
||||
// ... (Tune 'enc_options' as needed).
|
||||
WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
|
||||
while(<there are more frames>) {
|
||||
WebPConfig config;
|
||||
WebPConfigInit(&config);
|
||||
// ... (Tune 'config' as needed).
|
||||
WebPAnimEncoderAdd(enc, frame, duration, &config);
|
||||
}
|
||||
WebPAnimEncoderAssemble(enc, webp_data);
|
||||
WebPAnimEncoderDelete(enc);
|
||||
// ... (Write the 'webp_data' to a file, or re-mux it further).
|
||||
```
|
||||
|
||||
For a detailed AnimEncoder API reference, please refer to the header file
|
||||
(src/webp/mux.h).
|
||||
|
||||
## AnimDecoder API
|
||||
|
||||
This AnimDecoder API allows decoding (possibly) animated WebP images.
|
||||
|
||||
Code Example:
|
||||
|
||||
```c
|
||||
WebPAnimDecoderOptions dec_options;
|
||||
WebPAnimDecoderOptionsInit(&dec_options);
|
||||
// Tune 'dec_options' as needed.
|
||||
WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
|
||||
WebPAnimInfo anim_info;
|
||||
WebPAnimDecoderGetInfo(dec, &anim_info);
|
||||
for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
|
||||
while (WebPAnimDecoderHasMoreFrames(dec)) {
|
||||
uint8_t* buf;
|
||||
int timestamp;
|
||||
WebPAnimDecoderGetNext(dec, &buf, ×tamp);
|
||||
// ... (Render 'buf' based on 'timestamp').
|
||||
// ... (Do NOT free 'buf', as it is owned by 'dec').
|
||||
}
|
||||
WebPAnimDecoderReset(dec);
|
||||
}
|
||||
const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
|
||||
// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
|
||||
WebPAnimDecoderDelete(dec);
|
||||
```
|
||||
|
||||
For a detailed AnimDecoder API reference, please refer to the header file
|
||||
(src/webp/demux.h).
|
||||
@@ -0,0 +1,663 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:37 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>CWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>CWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp −
|
||||
compress an image file to a WebP file</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
[<i>options</i>] <i>input_file −o
|
||||
output_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>cwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>
|
||||
compresses an image using the WebP format. Input format can
|
||||
be either PNG, JPEG, TIFF, WebP or raw Y’CbCr samples.
|
||||
Note: Animated PNG and WebP files are not supported.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
−o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>cwebp</b> will perform compression
|
||||
but only report statistics. Using "−" as
|
||||
output name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with a
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be
|
||||
ignored.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A short usage summary.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−H,
|
||||
−longhelp</b></p>
|
||||
|
||||
<p style="margin-left:22%;">A summary of all the possible
|
||||
options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−lossless</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode the image without any
|
||||
loss. For images with fully transparent area, the invisible
|
||||
pixel values (R/G/B or Y/U/V) will be preserved only if the
|
||||
−exact option is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−near_lossless</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the level of
|
||||
near−lossless image preprocessing. This option adjusts
|
||||
pixel values to help compressibility, but has minimal impact
|
||||
on the visual quality. It triggers lossless compression mode
|
||||
automatically. The range is 0 (maximum preprocessing) to 100
|
||||
(no preprocessing, the default). The typical value is around
|
||||
60. Note that lossy with <b>−q 100</b> can at times
|
||||
yield better results.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−q</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossy compression (default), a small factor
|
||||
produces a smaller file with lower quality. Best quality is
|
||||
achieved by using a value of 100. <br>
|
||||
In case of lossless compression (specified by the
|
||||
<b>−lossless</b> option), a small factor enables
|
||||
faster compression speed, but produces a larger file.
|
||||
Maximum compression is achieved by using a value of 100.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−z</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Switch on
|
||||
<b>lossless</b> compression mode with the specified level
|
||||
between 0 and 9, with level 0 being the fastest, 9 being the
|
||||
slowest. Fast mode produces larger file size than slower
|
||||
ones. A good default is <b>−z 6</b>. This option is
|
||||
actually a shortcut for some predefined settings for quality
|
||||
and method. If options <b>−q</b> or <b>−m</b>
|
||||
are subsequently used, they will invalidate the effect of
|
||||
this option.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_q</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for alpha compression between 0 and 100. Lossless
|
||||
compression of alpha is achieved using a value of 100, while
|
||||
the lower values result in a lossy compression. The default
|
||||
is 100.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−preset</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a set of
|
||||
pre−defined parameters to suit a particular type of
|
||||
source material. Possible values are: <b>default</b>,
|
||||
<b>photo</b>, <b>picture</b>, <b>drawing</b>, <b>icon</b>,
|
||||
<b>text</b>. Since <b>−preset</b> overwrites the other
|
||||
parameters’ values (except the <b>−q</b> one),
|
||||
this option should preferably appear first in the order of
|
||||
the arguments.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−m</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
compression method to use. This parameter controls the trade
|
||||
off between encoding speed and the compressed file size and
|
||||
quality. Possible values range from 0 to 6. Default value is
|
||||
4. When higher values are used, the encoder will spend more
|
||||
time inspecting additional encoding possibilities and decide
|
||||
on the quality gain. Lower value can result in faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−crop</b>
|
||||
<i>x_position y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the source to a rectangle
|
||||
with top−left corner at coordinates
|
||||
(<b>x_position</b>, <b>y_position</b>) and size <b>width</b>
|
||||
x <b>height</b>. This cropping area must be fully contained
|
||||
within the source rectangle. Note: the cropping is applied
|
||||
<i>before</i> any scaling.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−resize</b> <i>width
|
||||
height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Resize the source to a
|
||||
rectangle with size <b>width</b> x <b>height</b>. If either
|
||||
(but not both) of the <b>width</b> or <b>height</b>
|
||||
parameters is 0, the value will be calculated preserving the
|
||||
aspect−ratio. Note: scaling is applied <i>after</i>
|
||||
cropping.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use
|
||||
multi−threading for encoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−low_memory</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Reduce memory usage of lossy
|
||||
encoding by saving four times the compressed size
|
||||
(typically). This will make the encoding slower and the
|
||||
output slightly different in size and distortion. This flag
|
||||
is only effective for methods 3 and up, and is off by
|
||||
default. Note that leaving this flag off will have some side
|
||||
effects on the bitstream: it forces certain bitstream
|
||||
features like number of partitions (forced to 1). Note that
|
||||
a more detailed report of bitstream size is printed by
|
||||
<b>cwebp</b> when using this option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOSSY
|
||||
OPTIONS</b> <br>
|
||||
These options are only effective when doing lossy encoding
|
||||
(the default, with or without alpha). <b><br>
|
||||
−size</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target size (in
|
||||
bytes) to try and reach for the compressed output. The
|
||||
compressor will make several passes of partial encoding in
|
||||
order to get as close as possible to this target. If both
|
||||
<b>−size</b> and <b>−psnr</b> are used,
|
||||
<b>−size</b> value will prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−psnr</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a target PSNR (in dB)
|
||||
to try and reach for the compressed output. The compressor
|
||||
will make several passes of partial encoding in order to get
|
||||
as close as possible to this target. If both
|
||||
<b>−size</b> and <b>−psnr</b> are used,
|
||||
<b>−size</b> value will prevail.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−pass</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Set a maximum number of passes
|
||||
to use during the dichotomy used by options
|
||||
<b>−size</b> or <b>−psnr</b>. Maximum value is
|
||||
10, default is 1. If options <b>−size</b> or
|
||||
<b>−psnr</b> were used, but <b>−pass</b>
|
||||
wasn’t specified, a default value of ’6’
|
||||
passes will be used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−qrange</b> <i>int
|
||||
int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specifies the permissible
|
||||
interval for the quality factor. This is particularly useful
|
||||
when using multi-pass (<b>−size</b> or
|
||||
<b>−psnr</b> options). Default is 0 100. If the
|
||||
quality factor is outside this range, it will be clamped. If
|
||||
the minimum value must be less or equal to the maximum
|
||||
one.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−af</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Turns
|
||||
auto−filter on. This algorithm will spend additional
|
||||
time optimizing the filtering strength to reach a
|
||||
well−balanced quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−jpeg_like</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the internal parameter
|
||||
mapping to better match the expected size of JPEG
|
||||
compression. This flag will generally produce an output file
|
||||
of similar size to its JPEG equivalent (for the same
|
||||
<b>−q</b> setting), but with less visual
|
||||
distortion.</p>
|
||||
|
||||
<p style="margin-left:11%;">Advanced options:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−f</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
strength of the deblocking filter, between 0 (no filtering)
|
||||
and 100 (maximum filtering). A value of 0 will turn off any
|
||||
filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear.
|
||||
Typical values are usually in the range of 20 to 50.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sharpness</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the sharpness of the
|
||||
filtering (if used). Range is 0 (sharpest) to 7 (least
|
||||
sharp). Default is 0.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−strong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use strong filtering (if
|
||||
filtering is being used thanks to the <b>−f</b>
|
||||
option). Strong filtering is on by default.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nostrong</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable strong filtering (if
|
||||
filtering is being used thanks to the <b>−f</b>
|
||||
option) and use simple filtering instead.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sharp_yuv</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Use more accurate and sharper
|
||||
RGB->YUV conversion if needed. Note that this process is
|
||||
slower than the default ’fast’ RGB->YUV
|
||||
conversion.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−sns</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the amplitude of the
|
||||
spatial noise shaping. Spatial noise shaping (or <b>sns</b>
|
||||
for short) refers to a general collection of built−in
|
||||
algorithms used to decide which area of the picture should
|
||||
use relatively less bits, and where else to better transfer
|
||||
these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is
|
||||
50.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−segments</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Change the number of partitions
|
||||
to use during the segmentation of the sns algorithm.
|
||||
Segments should be in range 1 to 4. Default value is 4. This
|
||||
option has no effect for methods 3 and up, unless
|
||||
<b>−low_memory</b> is used.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−partition_limit</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Degrade quality by limiting the
|
||||
number of bits used by some macroblocks. Range is 0 (no
|
||||
degradation, the default) to 100 (full degradation). Useful
|
||||
values are usually around 30−70 for moderately large
|
||||
images. In the VP8 format, the so−called control
|
||||
partition has a limit of 512k and is used to store the
|
||||
following information: whether the macroblock is skipped,
|
||||
which segment it belongs to, whether it is coded as intra
|
||||
4x4 or intra 16x16 mode, and finally the prediction modes to
|
||||
use for each of the sub−blocks. For a very large
|
||||
image, 512k only leaves room to few bits per 16x16
|
||||
macroblock. The absolute minimum is 4 bits per macroblock.
|
||||
Skip, segment, and mode information can use up almost all
|
||||
these 4 bits (although the case is unlikely), which is
|
||||
problematic for very large images. The partition_limit
|
||||
factor controls how frequently the most bit−costly
|
||||
mode (intra 4x4) will be used. This is useful in case the
|
||||
512k limit is reached and the following message is
|
||||
displayed: <i>Error code: 6 (PARTITION0_OVERFLOW: Partition
|
||||
#0 is too big to fit 512k)</i>. If using
|
||||
<b>−partition_limit</b> is not enough to meet the 512k
|
||||
constraint, one should use less segments in order to save
|
||||
more header bits per macroblock. See the
|
||||
<b>−segments</b> option.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>LOGGING
|
||||
OPTIONS</b> <br>
|
||||
These options control the level of output:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information (encoding time in particular).</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_psnr</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average PSNR
|
||||
(Peak−Signal−To−Noise ratio).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_ssim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report average SSIM
|
||||
(structural similarity metric, see
|
||||
https://en.wikipedia.org/wiki/SSIM for additional
|
||||
details).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−print_lsim</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Compute and report local
|
||||
similarity metric (sum of lowest error amongst the
|
||||
collocated pixel neighbors).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−progress</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Report encoding progress in
|
||||
percent.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−short</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Only print brief
|
||||
information (output file size and PSNR) for testing
|
||||
purposes.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−map</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Output additional
|
||||
ASCII−map of encoding information. Possible map values
|
||||
range from 1 to 6. This is only meant to help debugging.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>ADDITIONAL
|
||||
OPTIONS</b> <br>
|
||||
More advanced options are: <b><br>
|
||||
−s</b> <i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify that the input file
|
||||
actually consists of raw Y’CbCr samples following the
|
||||
ITU−R BT.601 recommendation, in 4:2:0 linear format.
|
||||
The luma plane has size <b>width</b> x <b>height</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−pre</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify some preprocessing
|
||||
steps. Using a value of ’2’ will trigger
|
||||
quality−dependent pseudo−random dithering during
|
||||
RGBA−>YUVA conversion (lossy compression only).</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_filter</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the predictive
|
||||
filtering method for the alpha plane. One of
|
||||
’none’, ’fast’ or
|
||||
’best’, in increasing complexity and slowness
|
||||
order. Default is ’fast’. Internally, alpha
|
||||
filtering is performed using four possible predictions
|
||||
(none, horizontal, vertical, gradient). The
|
||||
’best’ mode will try each mode in turn and pick
|
||||
the one which gives the smaller size. The ’fast’
|
||||
mode will just try to form an a priori guess without testing
|
||||
all modes.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_method</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the algorithm used for
|
||||
alpha compression: 0 or 1. Algorithm 0 denotes no
|
||||
compression, 1 uses WebP lossless format for compression.
|
||||
The default is 1.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−exact</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Preserve RGB values
|
||||
in transparent area. The default is off, to help
|
||||
compressibility.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−blend_alpha</b>
|
||||
<i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">This option blends the alpha
|
||||
channel (if present) with the source using the background
|
||||
color specified in hexadecimal as 0xrrggbb. The alpha
|
||||
channel is afterward reset to the opaque value 255.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−noalpha</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Using this option will discard
|
||||
the alpha channel.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−hint</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the hint about input
|
||||
image type. Possible values are: <b>photo</b>,
|
||||
<b>picture</b> or <b>graph</b>.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>exif</b>,
|
||||
<b>icc</b>, <b>xmp</b>. The default is <b>none</b>.</p>
|
||||
|
||||
<p style="margin-left:22%; margin-top: 1em">Note: each
|
||||
input format may not support all combinations.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−noasm</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="53%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Disable all
|
||||
assembly optimizations.</p></td>
|
||||
<td width="25%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">cwebp −q
|
||||
50 -lossless picture.png −o picture_lossless.webp <br>
|
||||
cwebp −q 70 picture_with_alpha.png −o
|
||||
picture_with_alpha.webp <br>
|
||||
cwebp −sns 70 −f 50 −size 60000
|
||||
picture.png −o picture.webp <br>
|
||||
cwebp −o picture.webp −−
|
||||
−−−picture.png</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>(1),
|
||||
<b>gif2webp</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,340 @@
|
||||
CWEBP(1) CWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
cwebp - compress an image file to a WebP file
|
||||
|
||||
SYNOPSIS
|
||||
cwebp [options] input_file -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the cwebp command.
|
||||
|
||||
cwebp compresses an image using the WebP format. Input format can be
|
||||
either PNG, JPEG, TIFF, WebP or raw Y'CbCr samples. Note: Animated PNG
|
||||
and WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, cwebp will
|
||||
perform compression but only report statistics. Using "-" as
|
||||
output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with a '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored.
|
||||
|
||||
-h, -help
|
||||
A short usage summary.
|
||||
|
||||
-H, -longhelp
|
||||
A summary of all the possible options.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossless
|
||||
Encode the image without any loss. For images with fully trans-
|
||||
parent area, the invisible pixel values (R/G/B or Y/U/V) will be
|
||||
preserved only if the -exact option is used.
|
||||
|
||||
-near_lossless int
|
||||
Specify the level of near-lossless image preprocessing. This
|
||||
option adjusts pixel values to help compressibility, but has
|
||||
minimal impact on the visual quality. It triggers lossless com-
|
||||
pression mode automatically. The range is 0 (maximum preprocess-
|
||||
ing) to 100 (no preprocessing, the default). The typical value
|
||||
is around 60. Note that lossy with -q 100 can at times yield
|
||||
better results.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossy compression (default), a small factor produces
|
||||
a smaller file with lower quality. Best quality is achieved by
|
||||
using a value of 100.
|
||||
In case of lossless compression (specified by the -lossless
|
||||
option), a small factor enables faster compression speed, but
|
||||
produces a larger file. Maximum compression is achieved by
|
||||
using a value of 100.
|
||||
|
||||
-z int Switch on lossless compression mode with the specified level
|
||||
between 0 and 9, with level 0 being the fastest, 9 being the
|
||||
slowest. Fast mode produces larger file size than slower ones. A
|
||||
good default is -z 6. This option is actually a shortcut for
|
||||
some predefined settings for quality and method. If options -q
|
||||
or -m are subsequently used, they will invalidate the effect of
|
||||
this option.
|
||||
|
||||
-alpha_q int
|
||||
Specify the compression factor for alpha compression between 0
|
||||
and 100. Lossless compression of alpha is achieved using a
|
||||
value of 100, while the lower values result in a lossy compres-
|
||||
sion. The default is 100.
|
||||
|
||||
-preset string
|
||||
Specify a set of pre-defined parameters to suit a particular
|
||||
type of source material. Possible values are: default, photo,
|
||||
picture, drawing, icon, text. Since -preset overwrites the other
|
||||
parameters' values (except the -q one), this option should
|
||||
preferably appear first in the order of the arguments.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and
|
||||
decide on the quality gain. Lower value can result in faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the source to a rectangle with top-left corner at coordi-
|
||||
nates (x_position, y_position) and size width x height. This
|
||||
cropping area must be fully contained within the source rectan-
|
||||
gle. Note: the cropping is applied before any scaling.
|
||||
|
||||
-resize width height
|
||||
Resize the source to a rectangle with size width x height. If
|
||||
either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio. Note:
|
||||
scaling is applied after cropping.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-low_memory
|
||||
Reduce memory usage of lossy encoding by saving four times the
|
||||
compressed size (typically). This will make the encoding slower
|
||||
and the output slightly different in size and distortion. This
|
||||
flag is only effective for methods 3 and up, and is off by
|
||||
default. Note that leaving this flag off will have some side
|
||||
effects on the bitstream: it forces certain bitstream features
|
||||
like number of partitions (forced to 1). Note that a more
|
||||
detailed report of bitstream size is printed by cwebp when using
|
||||
this option.
|
||||
|
||||
|
||||
LOSSY OPTIONS
|
||||
These options are only effective when doing lossy encoding (the
|
||||
default, with or without alpha).
|
||||
|
||||
|
||||
-size int
|
||||
Specify a target size (in bytes) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-psnr float
|
||||
Specify a target PSNR (in dB) to try and reach for the com-
|
||||
pressed output. The compressor will make several passes of par-
|
||||
tial encoding in order to get as close as possible to this tar-
|
||||
get. If both -size and -psnr are used, -size value will prevail.
|
||||
|
||||
-pass int
|
||||
Set a maximum number of passes to use during the dichotomy used
|
||||
by options -size or -psnr. Maximum value is 10, default is 1.
|
||||
If options -size or -psnr were used, but -pass wasn't specified,
|
||||
a default value of '6' passes will be used.
|
||||
|
||||
-qrange int int
|
||||
Specifies the permissible interval for the quality factor. This
|
||||
is particularly useful when using multi-pass (-size or -psnr
|
||||
options). Default is 0 100. If the quality factor is outside
|
||||
this range, it will be clamped. If the minimum value must be
|
||||
less or equal to the maximum one.
|
||||
|
||||
-af Turns auto-filter on. This algorithm will spend additional time
|
||||
optimizing the filtering strength to reach a well-balanced qual-
|
||||
ity.
|
||||
|
||||
-jpeg_like
|
||||
Change the internal parameter mapping to better match the
|
||||
expected size of JPEG compression. This flag will generally pro-
|
||||
duce an output file of similar size to its JPEG equivalent (for
|
||||
the same -q setting), but with less visual distortion.
|
||||
|
||||
|
||||
Advanced options:
|
||||
|
||||
|
||||
-f int Specify the strength of the deblocking filter, between 0 (no
|
||||
filtering) and 100 (maximum filtering). A value of 0 will turn
|
||||
off any filtering. Higher value will increase the strength of
|
||||
the filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear. Typical
|
||||
values are usually in the range of 20 to 50.
|
||||
|
||||
-sharpness int
|
||||
Specify the sharpness of the filtering (if used). Range is 0
|
||||
(sharpest) to 7 (least sharp). Default is 0.
|
||||
|
||||
-strong
|
||||
Use strong filtering (if filtering is being used thanks to the
|
||||
-f option). Strong filtering is on by default.
|
||||
|
||||
-nostrong
|
||||
Disable strong filtering (if filtering is being used thanks to
|
||||
the -f option) and use simple filtering instead.
|
||||
|
||||
-sharp_yuv
|
||||
Use more accurate and sharper RGB->YUV conversion if needed.
|
||||
Note that this process is slower than the default 'fast'
|
||||
RGB->YUV conversion.
|
||||
|
||||
-sns int
|
||||
Specify the amplitude of the spatial noise shaping. Spatial
|
||||
noise shaping (or sns for short) refers to a general collection
|
||||
of built-in algorithms used to decide which area of the picture
|
||||
should use relatively less bits, and where else to better trans-
|
||||
fer these bits. The possible range goes from 0 (algorithm is
|
||||
off) to 100 (the maximal effect). The default value is 50.
|
||||
|
||||
-segments int
|
||||
Change the number of partitions to use during the segmentation
|
||||
of the sns algorithm. Segments should be in range 1 to 4.
|
||||
Default value is 4. This option has no effect for methods 3 and
|
||||
up, unless -low_memory is used.
|
||||
|
||||
-partition_limit int
|
||||
Degrade quality by limiting the number of bits used by some mac-
|
||||
roblocks. Range is 0 (no degradation, the default) to 100 (full
|
||||
degradation). Useful values are usually around 30-70 for moder-
|
||||
ately large images. In the VP8 format, the so-called control
|
||||
partition has a limit of 512k and is used to store the following
|
||||
information: whether the macroblock is skipped, which segment it
|
||||
belongs to, whether it is coded as intra 4x4 or intra 16x16
|
||||
mode, and finally the prediction modes to use for each of the
|
||||
sub-blocks. For a very large image, 512k only leaves room to
|
||||
few bits per 16x16 macroblock. The absolute minimum is 4 bits
|
||||
per macroblock. Skip, segment, and mode information can use up
|
||||
almost all these 4 bits (although the case is unlikely), which
|
||||
is problematic for very large images. The partition_limit factor
|
||||
controls how frequently the most bit-costly mode (intra 4x4)
|
||||
will be used. This is useful in case the 512k limit is reached
|
||||
and the following message is displayed: Error code: 6 (PARTI-
|
||||
TION0_OVERFLOW: Partition #0 is too big to fit 512k). If using
|
||||
-partition_limit is not enough to meet the 512k constraint, one
|
||||
should use less segments in order to save more header bits per
|
||||
macroblock. See the -segments option.
|
||||
|
||||
|
||||
LOGGING OPTIONS
|
||||
These options control the level of output:
|
||||
|
||||
-v Print extra information (encoding time in particular).
|
||||
|
||||
-print_psnr
|
||||
Compute and report average PSNR (Peak-Signal-To-Noise ratio).
|
||||
|
||||
-print_ssim
|
||||
Compute and report average SSIM (structural similarity metric,
|
||||
see https://en.wikipedia.org/wiki/SSIM for additional details).
|
||||
|
||||
-print_lsim
|
||||
Compute and report local similarity metric (sum of lowest error
|
||||
amongst the collocated pixel neighbors).
|
||||
|
||||
-progress
|
||||
Report encoding progress in percent.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-short Only print brief information (output file size and PSNR) for
|
||||
testing purposes.
|
||||
|
||||
-map int
|
||||
Output additional ASCII-map of encoding information. Possible
|
||||
map values range from 1 to 6. This is only meant to help debug-
|
||||
ging.
|
||||
|
||||
|
||||
ADDITIONAL OPTIONS
|
||||
More advanced options are:
|
||||
|
||||
-s width height
|
||||
Specify that the input file actually consists of raw Y'CbCr sam-
|
||||
ples following the ITU-R BT.601 recommendation, in 4:2:0 linear
|
||||
format. The luma plane has size width x height.
|
||||
|
||||
-pre int
|
||||
Specify some preprocessing steps. Using a value of '2' will
|
||||
trigger quality-dependent pseudo-random dithering during
|
||||
RGBA->YUVA conversion (lossy compression only).
|
||||
|
||||
-alpha_filter string
|
||||
Specify the predictive filtering method for the alpha plane. One
|
||||
of 'none', 'fast' or 'best', in increasing complexity and slow-
|
||||
ness order. Default is 'fast'. Internally, alpha filtering is
|
||||
performed using four possible predictions (none, horizontal,
|
||||
vertical, gradient). The 'best' mode will try each mode in turn
|
||||
and pick the one which gives the smaller size. The 'fast' mode
|
||||
will just try to form an a priori guess without testing all
|
||||
modes.
|
||||
|
||||
-alpha_method int
|
||||
Specify the algorithm used for alpha compression: 0 or 1. Algo-
|
||||
rithm 0 denotes no compression, 1 uses WebP lossless format for
|
||||
compression. The default is 1.
|
||||
|
||||
-exact Preserve RGB values in transparent area. The default is off, to
|
||||
help compressibility.
|
||||
|
||||
-blend_alpha int
|
||||
This option blends the alpha channel (if present) with the
|
||||
source using the background color specified in hexadecimal as
|
||||
0xrrggbb. The alpha channel is afterward reset to the opaque
|
||||
value 255.
|
||||
|
||||
-noalpha
|
||||
Using this option will discard the alpha channel.
|
||||
|
||||
-hint string
|
||||
Specify the hint about input image type. Possible values are:
|
||||
photo, picture or graph.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, exif, icc, xmp.
|
||||
The default is none.
|
||||
|
||||
Note: each input format may not support all combinations.
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
cwebp -q 50 -lossless picture.png -o picture_lossless.webp
|
||||
cwebp -q 70 picture_with_alpha.png -o picture_with_alpha.webp
|
||||
cwebp -sns 70 -f 50 -size 60000 picture.png -o picture.webp
|
||||
cwebp -o picture.webp -- ---picture.png
|
||||
|
||||
|
||||
AUTHORS
|
||||
cwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
dwebp(1), gif2webp(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
March 17, 2022 CWEBP(1)
|
||||
@@ -0,0 +1,386 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:37 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>DWEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>DWEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp −
|
||||
decompress a WebP file to an image file</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
[<i>options</i>] <i>input_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>dwebp</b> command.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b>
|
||||
decompresses WebP files into PNG, PAM, PPM or PGM images.
|
||||
Note: Animated WebP files are not supported.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are:</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="3%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−h</b></p> </td>
|
||||
<td width="8%"></td>
|
||||
<td width="30%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print usage
|
||||
summary.</p> </td>
|
||||
<td width="48%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−o</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
file (as PNG format by default). Using "-" as
|
||||
output name will direct output to ’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "−", the data will be read
|
||||
from <i>stdin</i> instead of a file.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−bmp</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to uncompressed BMP.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−tiff</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to uncompressed TIFF.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−pam</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PAM (retains alpha).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−ppm</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PPM (discards alpha).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−pgm</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to PGM. The output consists of luma/chroma samples
|
||||
instead of RGB, using the IMC4 layout. This option is mainly
|
||||
for verification and debugging purposes.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−yuv</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Change the output
|
||||
format to raw YUV. The output consists of
|
||||
luma/chroma-U/chroma-V samples instead of RGB, saved
|
||||
sequentially as individual planes. This option is mainly for
|
||||
verification and debugging purposes.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofancy</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the fancy
|
||||
upscaler for YUV420. This may lead to jaggy edges
|
||||
(especially the red ones), but should be faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nofilter</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Don’t use the in-loop
|
||||
filtering process even if it is required by the bitstream.
|
||||
This may produce visible blocks on the non-compliant output,
|
||||
but it will make the decoding faster.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−dither</b>
|
||||
<i>strength</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify a dithering
|
||||
<b>strength</b> between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding
|
||||
banding artifacts.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−alpha_dither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If the compressed file contains
|
||||
a transparency plane that was quantized during compression,
|
||||
this flag will allow dithering the reconstructed plane in
|
||||
order to generate smoother transparency gradients.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−nodither</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Disable all dithering
|
||||
(default).</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="4%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="7%"></td>
|
||||
<td width="70%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use multi-threading
|
||||
for decoding, if possible.</p></td>
|
||||
<td width="8%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−crop</b>
|
||||
<i>x_position y_position width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Crop the decoded picture to a
|
||||
rectangle with top-left corner at coordinates
|
||||
(<b>x_position</b>, <b>y_position</b>) and size <b>width</b>
|
||||
x <b>height</b>. This cropping area must be fully contained
|
||||
within the source rectangle. The top-left corner will be
|
||||
snapped to even coordinates if needed. This option is meant
|
||||
to reduce the memory needed for cropping large images. Note:
|
||||
the cropping is applied <i>before</i> any scaling.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="7%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−flip</b></p> </td>
|
||||
<td width="4%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Flip decoded image
|
||||
vertically (can be useful for OpenGL textures for
|
||||
instance).</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−resize</b>,
|
||||
<b>−scale</b> <i>width height</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Rescale the decoded picture to
|
||||
dimension <b>width</b> x <b>height</b>. This option is
|
||||
mostly intended to reducing the memory needed to decode
|
||||
large images, when only a small version is needed
|
||||
(thumbnail, preview, etc.). Note: scaling is applied
|
||||
<i>after</i> cropping. If either (but not both) of the
|
||||
<b>width</b> or <b>height</b> parameters is 0, the value
|
||||
will be calculated preserving the aspect-ratio.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information (decoding time in particular).</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−noasm</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Disable all
|
||||
assembly optimizations.</p></td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">dwebp
|
||||
picture.webp −o output.png <br>
|
||||
dwebp picture.webp −ppm −o output.ppm <br>
|
||||
dwebp −o output.ppm −−
|
||||
−−−picture.webp <br>
|
||||
cat picture.webp | dwebp −o − −−
|
||||
− > output.ppm</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>dwebp</b> is
|
||||
a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Pascal Massimino
|
||||
<pascal.massimino@gmail.com>, for the Debian project
|
||||
(and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>gif2webp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>Output file
|
||||
format details</b> <br>
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html <br>
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html <br>
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html <br>
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,142 @@
|
||||
DWEBP(1) DWEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
dwebp - decompress a WebP file to an image file
|
||||
|
||||
SYNOPSIS
|
||||
dwebp [options] input_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the dwebp command.
|
||||
|
||||
dwebp decompresses WebP files into PNG, PAM, PPM or PGM images. Note:
|
||||
Animated WebP files are not supported.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-h Print usage summary.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-o string
|
||||
Specify the name of the output file (as PNG format by default).
|
||||
Using "-" as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from stdin instead
|
||||
of a file.
|
||||
|
||||
-bmp Change the output format to uncompressed BMP.
|
||||
|
||||
-tiff Change the output format to uncompressed TIFF.
|
||||
|
||||
-pam Change the output format to PAM (retains alpha).
|
||||
|
||||
-ppm Change the output format to PPM (discards alpha).
|
||||
|
||||
-pgm Change the output format to PGM. The output consists of
|
||||
luma/chroma samples instead of RGB, using the IMC4 layout. This
|
||||
option is mainly for verification and debugging purposes.
|
||||
|
||||
-yuv Change the output format to raw YUV. The output consists of
|
||||
luma/chroma-U/chroma-V samples instead of RGB, saved sequen-
|
||||
tially as individual planes. This option is mainly for verifica-
|
||||
tion and debugging purposes.
|
||||
|
||||
-nofancy
|
||||
Don't use the fancy upscaler for YUV420. This may lead to jaggy
|
||||
edges (especially the red ones), but should be faster.
|
||||
|
||||
-nofilter
|
||||
Don't use the in-loop filtering process even if it is required
|
||||
by the bitstream. This may produce visible blocks on the non-
|
||||
compliant output, but it will make the decoding faster.
|
||||
|
||||
-dither strength
|
||||
Specify a dithering strength between 0 and 100. Dithering is a
|
||||
post-processing effect applied to chroma components in lossy
|
||||
compression. It helps by smoothing gradients and avoiding band-
|
||||
ing artifacts.
|
||||
|
||||
-alpha_dither
|
||||
If the compressed file contains a transparency plane that was
|
||||
quantized during compression, this flag will allow dithering the
|
||||
reconstructed plane in order to generate smoother transparency
|
||||
gradients.
|
||||
|
||||
-nodither
|
||||
Disable all dithering (default).
|
||||
|
||||
-mt Use multi-threading for decoding, if possible.
|
||||
|
||||
-crop x_position y_position width height
|
||||
Crop the decoded picture to a rectangle with top-left corner at
|
||||
coordinates (x_position, y_position) and size width x height.
|
||||
This cropping area must be fully contained within the source
|
||||
rectangle. The top-left corner will be snapped to even coordi-
|
||||
nates if needed. This option is meant to reduce the memory
|
||||
needed for cropping large images. Note: the cropping is applied
|
||||
before any scaling.
|
||||
|
||||
-flip Flip decoded image vertically (can be useful for OpenGL textures
|
||||
for instance).
|
||||
|
||||
-resize, -scale width height
|
||||
Rescale the decoded picture to dimension width x height. This
|
||||
option is mostly intended to reducing the memory needed to
|
||||
decode large images, when only a small version is needed (thumb-
|
||||
nail, preview, etc.). Note: scaling is applied after cropping.
|
||||
If either (but not both) of the width or height parameters is 0,
|
||||
the value will be calculated preserving the aspect-ratio.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
-v Print extra information (decoding time in particular).
|
||||
|
||||
-noasm Disable all assembly optimizations.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
dwebp picture.webp -o output.png
|
||||
dwebp picture.webp -ppm -o output.ppm
|
||||
dwebp -o output.ppm -- ---picture.webp
|
||||
cat picture.webp | dwebp -o - -- - > output.ppm
|
||||
|
||||
|
||||
AUTHORS
|
||||
dwebp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Pascal Massimino <pascal.mas-
|
||||
simino@gmail.com>, for the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), gif2webp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
Output file format details
|
||||
PAM: http://netpbm.sourceforge.net/doc/pam.html
|
||||
PGM: http://netpbm.sourceforge.net/doc/pgm.html
|
||||
PPM: http://netpbm.sourceforge.net/doc/ppm.html
|
||||
PNG: http://www.libpng.org/pub/png/png-sitemap.html#info
|
||||
|
||||
|
||||
|
||||
November 17, 2021 DWEBP(1)
|
||||
@@ -0,0 +1,341 @@
|
||||
<!-- Creator : groff version 1.19.2 -->
|
||||
<!-- CreationDate: Fri Aug 5 18:48:38 2022 -->
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<meta name="generator" content="groff -Thtml, see www.gnu.org">
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<meta name="Content-Style" content="text/css">
|
||||
<style type="text/css">
|
||||
p { margin-top: 0; margin-bottom: 0; }
|
||||
pre { margin-top: 0; margin-bottom: 0; }
|
||||
table { margin-top: 0; margin-bottom: 0; }
|
||||
</style>
|
||||
<title>GIF2WEBP</title>
|
||||
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1 align=center>GIF2WEBP</h1>
|
||||
|
||||
<a href="#NAME">NAME</a><br>
|
||||
<a href="#SYNOPSIS">SYNOPSIS</a><br>
|
||||
<a href="#DESCRIPTION">DESCRIPTION</a><br>
|
||||
<a href="#OPTIONS">OPTIONS</a><br>
|
||||
<a href="#BUGS">BUGS</a><br>
|
||||
<a href="#EXAMPLES">EXAMPLES</a><br>
|
||||
<a href="#AUTHORS">AUTHORS</a><br>
|
||||
<a href="#SEE ALSO">SEE ALSO</a><br>
|
||||
|
||||
<hr>
|
||||
|
||||
|
||||
<a name="NAME"></a>
|
||||
<h2>NAME</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp
|
||||
− Convert a GIF image to WebP</p>
|
||||
|
||||
<a name="SYNOPSIS"></a>
|
||||
<h2>SYNOPSIS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
[<i>options</i>] <i>input_file.gif −o
|
||||
output_file.webp</i></p>
|
||||
|
||||
<a name="DESCRIPTION"></a>
|
||||
<h2>DESCRIPTION</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page documents the <b>gif2webp</b> command.</p>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
converts a GIF image to a WebP image.</p>
|
||||
|
||||
<a name="OPTIONS"></a>
|
||||
<h2>OPTIONS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">The basic
|
||||
options are: <b><br>
|
||||
−o</b> <i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the name of the output
|
||||
WebP file. If omitted, <b>gif2webp</b> will perform
|
||||
conversion but only report statistics. Using
|
||||
"−" as output name will direct output to
|
||||
’stdout’.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−−</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Explicitly specify the input
|
||||
file. This option is useful if the input file starts with an
|
||||
’−’ for instance. This option must appear
|
||||
<b>last</b>. Any other options afterward will be ignored. If
|
||||
the input file is "−", the data will be read
|
||||
from <i>stdin</i> instead of a file.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−h,
|
||||
−help</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Usage information.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−version</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Print the version number (as
|
||||
major.minor.revision) and exit.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−lossy</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Encode the image
|
||||
using lossy compression.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mixed</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Mixed compression
|
||||
mode: optimize compression of the image by picking either
|
||||
lossy or lossless compression for each frame
|
||||
heuristically.</p> </td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−q</b>
|
||||
<i>float</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the compression factor
|
||||
for RGB channels between 0 and 100. The default is 75. <br>
|
||||
In case of lossless compression (default), a small factor
|
||||
enables faster compression speed, but produces a larger
|
||||
file. Maximum compression is achieved by using a value of
|
||||
100. <br>
|
||||
In case of lossy compression (specified by the −lossy
|
||||
option), a small factor produces a smaller file with lower
|
||||
quality. Best quality is achieved by using a value of
|
||||
100.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−m</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Specify the
|
||||
compression method to use. This parameter controls the trade
|
||||
off between encoding speed and the compressed file size and
|
||||
quality. Possible values range from 0 to 6. Default value is
|
||||
4. When higher values are used, the encoder will spend more
|
||||
time inspecting additional encoding possibilities and decide
|
||||
on the quality gain. Lower value can result is faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.</p></td>
|
||||
</table>
|
||||
|
||||
<p style="margin-left:11%;"><b>−min_size</b></p>
|
||||
|
||||
<p style="margin-left:22%;">Encode image to achieve
|
||||
smallest size. This disables key frame insertion and picks
|
||||
the dispose method resulting in the smallest output for each
|
||||
frame. It uses lossless compression by default, but can be
|
||||
combined with −q, −m, −lossy or
|
||||
−mixed options.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−kmin</b> <i>int</i>
|
||||
<b><br>
|
||||
−kmax</b> <i>int</i></p>
|
||||
|
||||
<p style="margin-left:22%;">Specify the minimum and maximum
|
||||
distance between consecutive key frames (independently
|
||||
decodable frames) in the output animation. The tool will
|
||||
insert some key frames into the output animation as needed
|
||||
so that this criteria is satisfied. <br>
|
||||
A ’kmax’ value of 0 will turn off insertion of
|
||||
key frames. A ’kmax’ value of 1 will result in
|
||||
all frames being key frames. ’kmin’ value is not
|
||||
taken into account in both these special cases. Typical
|
||||
values are in the range 3 to 30. Default values are kmin =
|
||||
9, kmax = 17 for lossless compression and kmin = 3, kmax = 5
|
||||
for lossy compression. <br>
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50). <br>
|
||||
When lower values are used, more frames will be converted to
|
||||
key frames. This may lead to smaller number of frames
|
||||
required to decode a frame on average, thereby improving the
|
||||
decoding performance. But this may lead to slightly bigger
|
||||
file sizes. Higher values may lead to worse decoding
|
||||
performance, but smaller file sizes. <br>
|
||||
Some restrictions: <br>
|
||||
(i) kmin < kmax, <br>
|
||||
(ii) kmin >= kmax / 2 + 1 and <br>
|
||||
(iii) kmax - kmin <= 30. <br>
|
||||
If any of these restrictions are not met, they will be
|
||||
enforced automatically.</p>
|
||||
|
||||
<p style="margin-left:11%;"><b>−metadata</b>
|
||||
<i>string</i></p>
|
||||
|
||||
<p style="margin-left:22%;">A comma separated list of
|
||||
metadata to copy from the input to the output if present.
|
||||
Valid values: <b>all</b>, <b>none</b>, <b>icc</b>,
|
||||
<b>xmp</b>. The default is <b>xmp</b>.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−f</b>
|
||||
<i>int</i></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">For lossy encoding
|
||||
only (specified by the −lossy option). Specify the
|
||||
strength of the deblocking filter, between 0 (no filtering)
|
||||
and 100 (maximum filtering). A value of 0 will turn off any
|
||||
filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The
|
||||
higher the value the smoother the picture will appear.
|
||||
Typical values are usually in the range of 20 to 50.</p></td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−mt</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="78%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Use multi-threading
|
||||
for encoding, if possible.</p></td>
|
||||
</table>
|
||||
|
||||
|
||||
<p style="margin-left:11%;"><b>−loop_compatibility</b></p>
|
||||
|
||||
<p style="margin-left:22%;">If enabled, handle the loop
|
||||
information in a compatible fashion for Chrome version prior
|
||||
to M62 (inclusive) and Firefox.</p>
|
||||
|
||||
<table width="100%" border=0 rules="none" frame="void"
|
||||
cellspacing="0" cellpadding="0">
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−v</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Print extra
|
||||
information.</p> </td>
|
||||
<td width="42%">
|
||||
</td>
|
||||
<tr valign="top" align="left">
|
||||
<td width="11%"></td>
|
||||
<td width="9%">
|
||||
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top"><b>−quiet</b></p> </td>
|
||||
<td width="2%"></td>
|
||||
<td width="36%">
|
||||
|
||||
|
||||
<p style="margin-top: 1em" valign="top">Do not print
|
||||
anything.</p> </td>
|
||||
<td width="42%">
|
||||
</td>
|
||||
</table>
|
||||
|
||||
<a name="BUGS"></a>
|
||||
<h2>BUGS</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">Please report
|
||||
all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp <br>
|
||||
Patches welcome! See this page to get started:
|
||||
https://www.webmproject.org/code/contribute/submitting−patches/</p>
|
||||
|
||||
<a name="EXAMPLES"></a>
|
||||
<h2>EXAMPLES</h2>
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">gif2webp
|
||||
picture.gif −o picture.webp <br>
|
||||
gif2webp −q 70 picture.gif −o picture.webp <br>
|
||||
gif2webp −lossy −m 3 picture.gif −o
|
||||
picture_lossy.webp <br>
|
||||
gif2webp −lossy −f 50 picture.gif −o
|
||||
picture.webp <br>
|
||||
gif2webp −q 70 −o picture.webp −−
|
||||
−−−picture.gif <br>
|
||||
cat picture.gif | gif2webp −o − −−
|
||||
− > output.webp</p>
|
||||
|
||||
<a name="AUTHORS"></a>
|
||||
<h2>AUTHORS</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>gif2webp</b>
|
||||
is a part of libwebp and was written by the WebP team. <br>
|
||||
The latest source tree is available at
|
||||
https://chromium.googlesource.com/webm/libwebp</p>
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em">This manual
|
||||
page was written by Urvang Joshi <urvang@google.com>,
|
||||
for the Debian project (and may be used by others).</p>
|
||||
|
||||
<a name="SEE ALSO"></a>
|
||||
<h2>SEE ALSO</h2>
|
||||
|
||||
|
||||
|
||||
<p style="margin-left:11%; margin-top: 1em"><b>cwebp</b>(1),
|
||||
<b>dwebp</b>(1), <b>webpmux</b>(1) <br>
|
||||
Please refer to https://developers.google.com/speed/webp/
|
||||
for additional information.</p>
|
||||
<hr>
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,152 @@
|
||||
GIF2WEBP(1) GIF2WEBP(1)
|
||||
|
||||
|
||||
|
||||
NAME
|
||||
gif2webp - Convert a GIF image to WebP
|
||||
|
||||
SYNOPSIS
|
||||
gif2webp [options] input_file.gif -o output_file.webp
|
||||
|
||||
DESCRIPTION
|
||||
This manual page documents the gif2webp command.
|
||||
|
||||
gif2webp converts a GIF image to a WebP image.
|
||||
|
||||
OPTIONS
|
||||
The basic options are:
|
||||
|
||||
-o string
|
||||
Specify the name of the output WebP file. If omitted, gif2webp
|
||||
will perform conversion but only report statistics. Using "-"
|
||||
as output name will direct output to 'stdout'.
|
||||
|
||||
-- string
|
||||
Explicitly specify the input file. This option is useful if the
|
||||
input file starts with an '-' for instance. This option must
|
||||
appear last. Any other options afterward will be ignored. If
|
||||
the input file is "-", the data will be read from stdin instead
|
||||
of a file.
|
||||
|
||||
-h, -help
|
||||
Usage information.
|
||||
|
||||
-version
|
||||
Print the version number (as major.minor.revision) and exit.
|
||||
|
||||
-lossy Encode the image using lossy compression.
|
||||
|
||||
-mixed Mixed compression mode: optimize compression of the image by
|
||||
picking either lossy or lossless compression for each frame
|
||||
heuristically.
|
||||
|
||||
-q float
|
||||
Specify the compression factor for RGB channels between 0 and
|
||||
100. The default is 75.
|
||||
In case of lossless compression (default), a small factor
|
||||
enables faster compression speed, but produces a larger file.
|
||||
Maximum compression is achieved by using a value of 100.
|
||||
In case of lossy compression (specified by the -lossy option), a
|
||||
small factor produces a smaller file with lower quality. Best
|
||||
quality is achieved by using a value of 100.
|
||||
|
||||
-m int Specify the compression method to use. This parameter controls
|
||||
the trade off between encoding speed and the compressed file
|
||||
size and quality. Possible values range from 0 to 6. Default
|
||||
value is 4. When higher values are used, the encoder will spend
|
||||
more time inspecting additional encoding possibilities and
|
||||
decide on the quality gain. Lower value can result is faster
|
||||
processing time at the expense of larger file size and lower
|
||||
compression quality.
|
||||
|
||||
-min_size
|
||||
Encode image to achieve smallest size. This disables key frame
|
||||
insertion and picks the dispose method resulting in the smallest
|
||||
output for each frame. It uses lossless compression by default,
|
||||
but can be combined with -q, -m, -lossy or -mixed options.
|
||||
|
||||
-kmin int
|
||||
|
||||
-kmax int
|
||||
Specify the minimum and maximum distance between consecutive key
|
||||
frames (independently decodable frames) in the output animation.
|
||||
The tool will insert some key frames into the output animation
|
||||
as needed so that this criteria is satisfied.
|
||||
A 'kmax' value of 0 will turn off insertion of key frames. A
|
||||
'kmax' value of 1 will result in all frames being key frames.
|
||||
'kmin' value is not taken into account in both these special
|
||||
cases. Typical values are in the range 3 to 30. Default values
|
||||
are kmin = 9, kmax = 17 for lossless compression and kmin = 3,
|
||||
kmax = 5 for lossy compression.
|
||||
These two options are relevant only for animated images with
|
||||
large number of frames (>50).
|
||||
When lower values are used, more frames will be converted to key
|
||||
frames. This may lead to smaller number of frames required to
|
||||
decode a frame on average, thereby improving the decoding per-
|
||||
formance. But this may lead to slightly bigger file sizes.
|
||||
Higher values may lead to worse decoding performance, but
|
||||
smaller file sizes.
|
||||
Some restrictions:
|
||||
(i) kmin < kmax,
|
||||
(ii) kmin >= kmax / 2 + 1 and
|
||||
(iii) kmax - kmin <= 30.
|
||||
If any of these restrictions are not met, they will be enforced
|
||||
automatically.
|
||||
|
||||
-metadata string
|
||||
A comma separated list of metadata to copy from the input to the
|
||||
output if present. Valid values: all, none, icc, xmp. The
|
||||
default is xmp.
|
||||
|
||||
-f int For lossy encoding only (specified by the -lossy option). Spec-
|
||||
ify the strength of the deblocking filter, between 0 (no filter-
|
||||
ing) and 100 (maximum filtering). A value of 0 will turn off
|
||||
any filtering. Higher value will increase the strength of the
|
||||
filtering process applied after decoding the picture. The higher
|
||||
the value the smoother the picture will appear. Typical values
|
||||
are usually in the range of 20 to 50.
|
||||
|
||||
-mt Use multi-threading for encoding, if possible.
|
||||
|
||||
-loop_compatibility
|
||||
If enabled, handle the loop information in a compatible fashion
|
||||
for Chrome version prior to M62 (inclusive) and Firefox.
|
||||
|
||||
-v Print extra information.
|
||||
|
||||
-quiet Do not print anything.
|
||||
|
||||
|
||||
BUGS
|
||||
Please report all bugs to the issue tracker:
|
||||
https://bugs.chromium.org/p/webp
|
||||
Patches welcome! See this page to get started: https://www.webmpro-
|
||||
ject.org/code/contribute/submitting-patches/
|
||||
|
||||
|
||||
EXAMPLES
|
||||
gif2webp picture.gif -o picture.webp
|
||||
gif2webp -q 70 picture.gif -o picture.webp
|
||||
gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp
|
||||
gif2webp -lossy -f 50 picture.gif -o picture.webp
|
||||
gif2webp -q 70 -o picture.webp -- ---picture.gif
|
||||
cat picture.gif | gif2webp -o - -- - > output.webp
|
||||
|
||||
|
||||
AUTHORS
|
||||
gif2webp is a part of libwebp and was written by the WebP team.
|
||||
The latest source tree is available at https://chromium.google-
|
||||
source.com/webm/libwebp
|
||||
|
||||
This manual page was written by Urvang Joshi <urvang@google.com>, for
|
||||
the Debian project (and may be used by others).
|
||||
|
||||
|
||||
SEE ALSO
|
||||
cwebp(1), dwebp(1), webpmux(1)
|
||||
Please refer to https://developers.google.com/speed/webp/ for addi-
|
||||
tional information.
|
||||
|
||||
|
||||
|
||||
November 17, 2021 GIF2WEBP(1)
|
||||
Some files were not shown because too many files have changed in this diff Show More
Reference in New Issue
Block a user