includes/media/GIFHandler.php

   1 <?php
   2 /**
   3  * Handler for GIF images.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Media
  22  */
  23
  24 /**
  25  * Handler for GIF images.
  26  *
  27  * @ingroup Media
  28  */
  29 class GIFHandler extends BitmapHandler {
  30         const BROKEN_FILE = '0'; // value to store in img_metadata if error extracting metadata.
  31
  32         public function getMetadata( $image, $filename ) {
  33                 try {
  34                         $parsedGIFMetadata = BitmapMetadataHandler::GIF( $filename );
  35                 } catch ( Exception $e ) {
  36                         // Broken file?
  37                         wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
  38
  39                         return self::BROKEN_FILE;
  40                 }
  41
  42                 return serialize( $parsedGIFMetadata );
  43         }
  44
  45         /**
  46          * @param File $image
  47          * @param bool|IContextSource $context Context to use (optional)
  48          * @return array|bool
  49          */
  50         public function formatMetadata( $image, $context = false ) {
  51                 $meta = $this->getCommonMetaArray( $image );
  52                 if ( count( $meta ) === 0 ) {
  53                         return false;
  54                 }
  55
  56                 return $this->formatMetadataHelper( $meta, $context );
  57         }
  58
  59         /**
  60          * Return the standard metadata elements for #filemetadata parser func.
  61          * @param File $image
  62          * @return array|bool
  63          */
  64         public function getCommonMetaArray( File $image ) {
  65                 $meta = $image->getMetadata();
  66
  67                 if ( !$meta ) {
  68                         return [];
  69                 }
  70                 $meta = unserialize( $meta );
  71                 if ( !isset( $meta['metadata'] ) ) {
  72                         return [];
  73                 }
  74                 unset( $meta['metadata']['_MW_GIF_VERSION'] );
  75
  76                 return $meta['metadata'];
  77         }
  78
  79         /**
  80          * @todo Add unit tests
  81          *
  82          * @param File $image
  83          * @return bool
  84          */
  85         function getImageArea( $image ) {
  86                 $ser = $image->getMetadata();
  87                 if ( $ser ) {
  88                         $metadata = unserialize( $ser );
  89                         if ( isset( $metadata['frameCount'] ) && $metadata['frameCount'] > 0 ) {
  90                                 return $image->getWidth() * $image->getHeight() * $metadata['frameCount'];
  91                         } else {
  92                                 return $image->getWidth() * $image->getHeight();
  93                         }
  94                 } else {
  95                         return $image->getWidth() * $image->getHeight();
  96                 }
  97         }
  98
  99         /**
 100          * @param File $image
 101          * @return bool
 102          */
 103         function isAnimatedImage( $image ) {
 104                 $ser = $image->getMetadata();
 105                 if ( $ser ) {
 106                         $metadata = unserialize( $ser );
 107                         if ( isset( $metadata['frameCount'] ) && $metadata['frameCount'] > 1 ) {
 108                                 return true;
 109                         }
 110                 }
 111
 112                 return false;
 113         }
 114
 115         /**
 116          * We cannot animate thumbnails that are bigger than a particular size
 117          * @param File $file
 118          * @return bool
 119          */
 120         function canAnimateThumbnail( $file ) {
 121                 global $wgMaxAnimatedGifArea;
 122                 $answer = $this->getImageArea( $file ) <= $wgMaxAnimatedGifArea;
 123
 124                 return $answer;
 125         }
 126
 127         function getMetadataType( $image ) {
 128                 return 'parsed-gif';
 129         }
 130
 131         public function isMetadataValid( $image, $metadata ) {
 132                 if ( $metadata === self::BROKEN_FILE ) {
 133                         // Do not repetitivly regenerate metadata on broken file.
 134                         return self::METADATA_GOOD;
 135                 }
 136
 137                 Wikimedia\suppressWarnings();
 138                 $data = unserialize( $metadata );
 139                 Wikimedia\restoreWarnings();
 140
 141                 if ( !$data || !is_array( $data ) ) {
 142                         wfDebug( __METHOD__ . " invalid GIF metadata\n" );
 143
 144                         return self::METADATA_BAD;
 145                 }
 146
 147                 if ( !isset( $data['metadata']['_MW_GIF_VERSION'] )
 148                         || $data['metadata']['_MW_GIF_VERSION'] != GIFMetadataExtractor::VERSION
 149                 ) {
 150                         wfDebug( __METHOD__ . " old but compatible GIF metadata\n" );
 151
 152                         return self::METADATA_COMPATIBLE;
 153                 }
 154
 155                 return self::METADATA_GOOD;
 156         }
 157
 158         /**
 159          * @param File $image
 160          * @return string
 161          */
 162         public function getLongDesc( $image ) {
 163                 global $wgLang;
 164
 165                 $original = parent::getLongDesc( $image );
 166
 167                 Wikimedia\suppressWarnings();
 168                 $metadata = unserialize( $image->getMetadata() );
 169                 Wikimedia\restoreWarnings();
 170
 171                 if ( !$metadata || $metadata['frameCount'] <= 1 ) {
 172                         return $original;
 173                 }
 174
 175                 /* Preserve original image info string, but strip the last char ')' so we can add even more */
 176                 $info = [];
 177                 $info[] = $original;
 178
 179                 if ( $metadata['looped'] ) {
 180                         $info[] = wfMessage( 'file-info-gif-looped' )->parse();
 181                 }
 182
 183                 if ( $metadata['frameCount'] > 1 ) {
 184                         $info[] = wfMessage( 'file-info-gif-frames' )->numParams( $metadata['frameCount'] )->parse();
 185                 }
 186
 187                 if ( $metadata['duration'] ) {
 188                         $info[] = $wgLang->formatTimePeriod( $metadata['duration'] );
 189                 }
 190
 191                 return $wgLang->commaList( $info );
 192         }
 193
 194         /**
 195          * Return the duration of the GIF file.
 196          *
 197          * Shown in the &query=imageinfo&iiprop=size api query.
 198          *
 199          * @param File $file
 200          * @return float The duration of the file.
 201          */
 202         public function getLength( $file ) {
 203                 $serMeta = $file->getMetadata();
 204                 Wikimedia\suppressWarnings();
 205                 $metadata = unserialize( $serMeta );
 206                 Wikimedia\restoreWarnings();
 207
 208                 if ( !$metadata || !isset( $metadata['duration'] ) || !$metadata['duration'] ) {
 209                         return 0.0;
 210                 } else {
 211                         return (float)$metadata['duration'];
 212                 }
 213         }
 214 }