includes/media/Bitmap.php

   1 <?php
   2
   3 /**
   4  * @addtogroup Media
   5  */
   6 class BitmapHandler extends ImageHandler {
   7         function normaliseParams( $image, &$params ) {
   8                 global $wgMaxImageArea;
   9                 if ( !parent::normaliseParams( $image, $params ) ) {
  10                         return false;
  11                 }
  12
  13                 $mimeType = $image->getMimeType();
  14                 $srcWidth = $image->getWidth( $params['page'] );
  15                 $srcHeight = $image->getHeight( $params['page'] );
  16
  17                 # Don't thumbnail an image so big that it will fill hard drives and send servers into swap
  18                 # JPEG has the handy property of allowing thumbnailing without full decompression, so we make
  19                 # an exception for it.
  20                 if ( $mimeType !== 'image/jpeg' &&
  21                         $srcWidth * $srcHeight > $wgMaxImageArea )
  22                 {
  23                         return false;
  24                 }
  25
  26                 # Don't make an image bigger than the source
  27                 $params['physicalWidth'] = $params['width'];
  28                 $params['physicalHeight'] = $params['height'];
  29
  30                 if ( $params['physicalWidth'] >= $srcWidth ) {
  31                         $params['physicalWidth'] = $srcWidth;
  32                         $params['physicalHeight'] = $srcHeight;
  33                         return true;
  34                 }
  35
  36                 return true;
  37         }
  38
  39         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
  40                 global $wgUseImageMagick, $wgImageMagickConvertCommand;
  41                 global $wgCustomConvertCommand;
  42                 global $wgSharpenParameter, $wgSharpenReductionThreshold;
  43
  44                 if ( !$this->normaliseParams( $image, $params ) ) {
  45                         return new TransformParameterError( $params );
  46                 }
  47                 $physicalWidth = $params['physicalWidth'];
  48                 $physicalHeight = $params['physicalHeight'];
  49                 $clientWidth = $params['width'];
  50                 $clientHeight = $params['height'];
  51                 $srcWidth = $image->getWidth();
  52                 $srcHeight = $image->getHeight();
  53                 $mimeType = $image->getMimeType();
  54                 $srcPath = $image->getPath();
  55                 $retval = 0;
  56                 wfDebug( __METHOD__.": creating {$physicalWidth}x{$physicalHeight} thumbnail at $dstPath\n" );
  57
  58                 if ( $physicalWidth == $srcWidth && $physicalHeight == $srcHeight ) {
  59                         # normaliseParams (or the user) wants us to return the unscaled image
  60                         wfDebug( __METHOD__.": returning unscaled image\n" );
  61                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  62                 }
  63
  64                 if ( !$dstPath ) {
  65                         // No output path available, client side scaling only
  66                         $scaler = 'client';
  67                 } elseif ( $wgUseImageMagick ) {
  68                         $scaler = 'im';
  69                 } elseif ( $wgCustomConvertCommand ) {
  70                         $scaler = 'custom';
  71                 } elseif ( function_exists( 'imagecreatetruecolor' ) ) {
  72                         $scaler = 'gd';
  73                 } else {
  74                         $scaler = 'client';
  75                 }
  76
  77                 if ( $scaler == 'client' ) {
  78                         # Client-side image scaling, use the source URL
  79                         # Using the destination URL in a TRANSFORM_LATER request would be incorrect
  80                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  81                 }
  82
  83                 if ( $flags & self::TRANSFORM_LATER ) {
  84                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
  85                 }
  86
  87                 if ( !wfMkdirParents( dirname( $dstPath ) ) ) {
  88                         wfDebug( "Unable to create thumbnail destination directory, falling back to client scaling\n" );
  89                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  90                 }
  91
  92                 if ( $scaler == 'im' ) {
  93                         # use ImageMagick
  94
  95                         $sharpen = '';
  96                         if ( $mimeType == 'image/jpeg' ) {
  97                                 $quality = "-quality 80"; // 80%
  98                                 # Sharpening, see bug 6193
  99                                 if ( ( $physicalWidth + $physicalHeight ) / ( $srcWidth + $srcHeight ) < $wgSharpenReductionThreshold ) {
 100                                         $sharpen = "-sharpen " . wfEscapeShellArg( $wgSharpenParameter );
 101                                 }
 102                         } elseif ( $mimeType == 'image/png' ) {
 103                                 $quality = "-quality 95"; // zlib 9, adaptive filtering
 104                         } else {
 105                                 $quality = ''; // default
 106                         }
 107
 108                         # Specify white background color, will be used for transparent images
 109                         # in Internet Explorer/Windows instead of default black.
 110
 111                         # Note, we specify "-size {$physicalWidth}" and NOT "-size {$physicalWidth}x{$physicalHeight}".
 112                         # It seems that ImageMagick has a bug wherein it produces thumbnails of
 113                         # the wrong size in the second case.
 114
 115                         $cmd  =  wfEscapeShellArg($wgImageMagickConvertCommand) .
 116                                 " {$quality} -background white -size {$physicalWidth} ".
 117                                 wfEscapeShellArg($srcPath) .
 118                                 // Coalesce is needed to scale animated GIFs properly (bug 1017).
 119                                 ' -coalesce ' .
 120                                 // For the -resize option a "!" is needed to force exact size,
 121                                 // or ImageMagick may decide your ratio is wrong and slice off
 122                                 // a pixel.
 123                                 " -thumbnail " . wfEscapeShellArg( "{$physicalWidth}x{$physicalHeight}!" ) .
 124                                 " -depth 8 $sharpen " .
 125                                 wfEscapeShellArg($dstPath) . " 2>&1";
 126                         wfDebug( __METHOD__.": running ImageMagick: $cmd\n");
 127                         wfProfileIn( 'convert' );
 128                         $err = wfShellExec( $cmd, $retval );
 129                         wfProfileOut( 'convert' );
 130                 } elseif( $scaler == 'custom' ) {
 131                         # Use a custom convert command
 132                         # Variables: %s %d %w %h
 133                         $src = wfEscapeShellArg( $srcPath );
 134                         $dst = wfEscapeShellArg( $dstPath );
 135                         $cmd = $wgCustomConvertCommand;
 136                         $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 137                         $cmd = str_replace( '%h', $physicalHeight, str_replace( '%w', $physicalWidth, $cmd ) ); # Size
 138                         wfDebug( __METHOD__.": Running custom convert command $cmd\n" );
 139                         wfProfileIn( 'convert' );
 140                         $err = wfShellExec( $cmd, $retval );
 141                         wfProfileOut( 'convert' );
 142                 } else /* $scaler == 'gd' */ {
 143                         # Use PHP's builtin GD library functions.
 144                         #
 145                         # First find out what kind of file this is, and select the correct
 146                         # input routine for this.
 147
 148                         $typemap = array(
 149                                 'image/gif'          => array( 'imagecreatefromgif',  'palette',   'imagegif'  ),
 150                                 'image/jpeg'         => array( 'imagecreatefromjpeg', 'truecolor', array( __CLASS__, 'imageJpegWrapper' ) ),
 151                                 'image/png'          => array( 'imagecreatefrompng',  'bits',      'imagepng'  ),
 152                                 'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette',   'imagewbmp'  ),
 153                                 'image/xbm'          => array( 'imagecreatefromxbm',  'palette',   'imagexbm'  ),
 154                         );
 155                         if( !isset( $typemap[$mimeType] ) ) {
 156                                 $err = 'Image type not supported';
 157                                 wfDebug( "$err\n" );
 158                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 159                         }
 160                         list( $loader, $colorStyle, $saveType ) = $typemap[$mimeType];
 161
 162                         if( !function_exists( $loader ) ) {
 163                                 $err = "Incomplete GD library configuration: missing function $loader";
 164                                 wfDebug( "$err\n" );
 165                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 166                         }
 167
 168                         $src_image = call_user_func( $loader, $srcPath );
 169                         $dst_image = imagecreatetruecolor( $physicalWidth, $physicalHeight );
 170
 171                         // Initialise the destination image to transparent instead of
 172                         // the default solid black, to support PNG and GIF transparency nicely
 173                         $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 174                         imagecolortransparent( $dst_image, $background );
 175                         imagealphablending( $dst_image, false );
 176
 177                         if( $colorStyle == 'palette' ) {
 178                                 // Don't resample for paletted GIF images.
 179                                 // It may just uglify them, and completely breaks transparency.
 180                                 imagecopyresized( $dst_image, $src_image,
 181                                         0,0,0,0,
 182                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 183                         } else {
 184                                 imagecopyresampled( $dst_image, $src_image,
 185                                         0,0,0,0,
 186                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 187                         }
 188
 189                         imagesavealpha( $dst_image, true );
 190
 191                         call_user_func( $saveType, $dst_image, $dstPath );
 192                         imagedestroy( $dst_image );
 193                         imagedestroy( $src_image );
 194                         $retval = 0;
 195                 }
 196
 197                 $removed = $this->removeBadFile( $dstPath, $retval );
 198                 if ( $retval != 0 || $removed ) {
 199                         wfDebugLog( 'thumbnail',
 200                                 sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 201                                         wfHostname(), $retval, trim($err), $cmd ) );
 202                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 203                 } else {
 204                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 205                 }
 206         }
 207
 208         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 209                 imageinterlace( $dst_image );
 210                 imagejpeg( $dst_image, $thumbPath, 95 );
 211         }
 212
 213
 214         function getMetadata( $image, $filename ) {
 215                 global $wgShowEXIF;
 216                 if( $wgShowEXIF && file_exists( $filename ) ) {
 217                         $exif = new Exif( $filename );
 218                         $data = $exif->getFilteredData();
 219                         if ( $data ) {
 220                                 $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 221                                 return serialize( $data );
 222                         } else {
 223                                 return '0';
 224                         }
 225                 } else {
 226                         return '';
 227                 }
 228         }
 229
 230         function getMetadataType( $image ) {
 231                 return 'exif';
 232         }
 233
 234         function isMetadataValid( $image, $metadata ) {
 235                 global $wgShowEXIF;
 236                 if ( !$wgShowEXIF ) {
 237                         # Metadata disabled and so an empty field is expected
 238                         return true;
 239                 }
 240                 if ( $metadata === '0' ) {
 241                         # Special value indicating that there is no EXIF data in the file
 242                         return true;
 243                 }
 244                 $exif = @unserialize( $metadata );
 245                 if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
 246                         $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
 247                 {
 248                         # Wrong version
 249                         wfDebug( __METHOD__.": wrong version\n" );
 250                         return false;
 251                 }
 252                 return true;
 253         }
 254
 255         /**
 256          * Get a list of EXIF metadata items which should be displayed when
 257          * the metadata table is collapsed.
 258          *
 259          * @return array of strings
 260          * @access private
 261          */
 262         function visibleMetadataFields() {
 263                 $fields = array();
 264                 $lines = explode( "\n", wfMsgForContent( 'metadata-fields' ) );
 265                 foreach( $lines as $line ) {
 266                         $matches = array();
 267                         if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
 268                                 $fields[] = $matches[1];
 269                         }
 270                 }
 271                 $fields = array_map( 'strtolower', $fields );
 272                 return $fields;
 273         }
 274
 275         function formatMetadata( $image ) {
 276                 $result = array(
 277                         'visible' => array(),
 278                         'collapsed' => array()
 279                 );
 280                 $metadata = $image->getMetadata();
 281                 if ( !$metadata ) {
 282                         return false;
 283                 }
 284                 $exif = unserialize( $metadata );
 285                 if ( !$exif ) {
 286                         return false;
 287                 }
 288                 unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
 289                 $format = new FormatExif( $exif );
 290
 291                 $formatted = $format->getFormattedData();
 292                 // Sort fields into visible and collapsed
 293                 $visibleFields = $this->visibleMetadataFields();
 294                 foreach ( $formatted as $name => $value ) {
 295                         $tag = strtolower( $name );
 296                         self::addMeta( $result,
 297                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 298                                 'exif',
 299                                 $tag,
 300                                 $value
 301                         );
 302                 }
 303                 return $result;
 304         }
 305 }
 306
 307