includes/media/Bitmap.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup Media
   5  */
   6
   7 /**
   8  * @ingroup Media
   9  */
  10 class BitmapHandler extends ImageHandler {
  11         function normaliseParams( $image, &$params ) {
  12                 global $wgMaxImageArea;
  13                 if ( !parent::normaliseParams( $image, $params ) ) {
  14                         return false;
  15                 }
  16
  17                 $mimeType = $image->getMimeType();
  18                 $srcWidth = $image->getWidth( $params['page'] );
  19                 $srcHeight = $image->getHeight( $params['page'] );
  20
  21                 # Don't make an image bigger than the source
  22                 $params['physicalWidth'] = $params['width'];
  23                 $params['physicalHeight'] = $params['height'];
  24
  25                 if ( $params['physicalWidth'] >= $srcWidth ) {
  26                         $params['physicalWidth'] = $srcWidth;
  27                         $params['physicalHeight'] = $srcHeight;
  28                         # Skip scaling limit checks if no scaling is required
  29                         if( !$image->mustRender() )
  30                                 return true;
  31                 }
  32
  33                 # Don't thumbnail an image so big that it will fill hard drives and send servers into swap
  34                 # JPEG has the handy property of allowing thumbnailing without full decompression, so we make
  35                 # an exception for it.
  36                 if ( $mimeType !== 'image/jpeg' &&
  37                         $srcWidth * $srcHeight > $wgMaxImageArea )
  38                 {
  39                         return false;
  40                 }
  41
  42                 return true;
  43         }
  44
  45
  46         // Function that returns the number of pixels to be thumbnailed.
  47         // Intended for animated GIFs to multiply by the number of frames.
  48         function getImageArea( $image, $width, $height ) {
  49                 return $width * $height;
  50         }
  51
  52         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
  53                 global $wgUseImageMagick, $wgImageMagickConvertCommand, $wgImageMagickTempDir;
  54                 global $wgCustomConvertCommand, $wgUseImageResize;
  55                 global $wgSharpenParameter, $wgSharpenReductionThreshold;
  56                 global $wgMaxAnimatedGifArea;
  57
  58                 if ( !$this->normaliseParams( $image, $params ) ) {
  59                         return new TransformParameterError( $params );
  60                 }
  61                 $physicalWidth = $params['physicalWidth'];
  62                 $physicalHeight = $params['physicalHeight'];
  63                 $clientWidth = $params['width'];
  64                 $clientHeight = $params['height'];
  65                 $comment = isset( $params['descriptionUrl'] ) ? "File source: ". $params['descriptionUrl'] : '';
  66                 $srcWidth = $image->getWidth();
  67                 $srcHeight = $image->getHeight();
  68                 $mimeType = $image->getMimeType();
  69                 $srcPath = $image->getPath();
  70                 $retval = 0;
  71                 wfDebug( __METHOD__.": creating {$physicalWidth}x{$physicalHeight} thumbnail at $dstPath\n" );
  72
  73                 if ( !$image->mustRender() && $physicalWidth == $srcWidth && $physicalHeight == $srcHeight ) {
  74                         # normaliseParams (or the user) wants us to return the unscaled image
  75                         wfDebug( __METHOD__.": returning unscaled image\n" );
  76                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  77                 }
  78
  79                 if ( !$dstPath ) {
  80                         // No output path available, client side scaling only
  81                         $scaler = 'client';
  82                 } elseif( !$wgUseImageResize ) {
  83                         $scaler = 'client';
  84                 } elseif ( $wgUseImageMagick ) {
  85                         $scaler = 'im';
  86                 } elseif ( $wgCustomConvertCommand ) {
  87                         $scaler = 'custom';
  88                 } elseif ( function_exists( 'imagecreatetruecolor' ) ) {
  89                         $scaler = 'gd';
  90                 } else {
  91                         $scaler = 'client';
  92                 }
  93                 wfDebug( __METHOD__.": scaler $scaler\n" );
  94
  95                 if ( $scaler == 'client' ) {
  96                         # Client-side image scaling, use the source URL
  97                         # Using the destination URL in a TRANSFORM_LATER request would be incorrect
  98                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  99                 }
 100
 101                 if ( $flags & self::TRANSFORM_LATER ) {
 102                         wfDebug( __METHOD__.": Transforming later per flags.\n" );
 103                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 104                 }
 105
 106                 if ( !wfMkdirParents( dirname( $dstPath ) ) ) {
 107                         wfDebug( __METHOD__.": Unable to create thumbnail destination directory, falling back to client scaling\n" );
 108                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
 109                 }
 110
 111                 if ( $scaler == 'im' ) {
 112                         # use ImageMagick
 113
 114                         $quality = '';
 115                         $sharpen = '';
 116                         $scene = false;
 117                         $animation = '';
 118                         if ( $mimeType == 'image/jpeg' ) {
 119                                 $quality = "-quality 80"; // 80%
 120                                 # Sharpening, see bug 6193
 121                                 if ( ( $physicalWidth + $physicalHeight ) / ( $srcWidth + $srcHeight ) < $wgSharpenReductionThreshold ) {
 122                                         $sharpen = "-sharpen " . wfEscapeShellArg( $wgSharpenParameter );
 123                                 }
 124                         } elseif ( $mimeType == 'image/png' ) {
 125                                 $quality = "-quality 95"; // zlib 9, adaptive filtering
 126                         } elseif( $mimeType == 'image/gif' ) {
 127                                 if( $this->getImageArea( $image, $srcWidth, $srcHeight ) > $wgMaxAnimatedGifArea ) {
 128                                         // Extract initial frame only; we're so big it'll
 129                                         // be a total drag. :P
 130                                         $scene = 0;
 131                                 } else {
 132                                         // Coalesce is needed to scale animated GIFs properly (bug 1017).
 133                                         $animation = ' -coalesce ';
 134                                 }
 135                         }
 136
 137                         if ( strval( $wgImageMagickTempDir ) !== '' ) {
 138                                 $tempEnv = 'MAGICK_TMPDIR=' . wfEscapeShellArg( $wgImageMagickTempDir ) . ' ';
 139                         } else {
 140                                 $tempEnv = '';
 141                         }
 142
 143                         # Specify white background color, will be used for transparent images
 144                         # in Internet Explorer/Windows instead of default black.
 145
 146                         # Note, we specify "-size {$physicalWidth}" and NOT "-size {$physicalWidth}x{$physicalHeight}".
 147                         # It seems that ImageMagick has a bug wherein it produces thumbnails of
 148                         # the wrong size in the second case.
 149
 150                         $cmd  =
 151                                 $tempEnv .
 152                                 wfEscapeShellArg( $wgImageMagickConvertCommand ) .
 153                                 " {$quality} -background white -size {$physicalWidth} ".
 154                                 wfEscapeShellArg( $this->escapeMagickInput( $srcPath, $scene ) ) .
 155                                 $animation .
 156                                 // For the -resize option a "!" is needed to force exact size,
 157                                 // or ImageMagick may decide your ratio is wrong and slice off
 158                                 // a pixel.
 159                                 " -thumbnail " . wfEscapeShellArg( "{$physicalWidth}x{$physicalHeight}!" ) .
 160                                 // Add the source url as a comment to the thumb.
 161                                 " -set comment " . wfEscapeShellArg( $this->escapeMagickProperty( $comment ) ) .
 162                                 " -depth 8 $sharpen " .
 163                                 wfEscapeShellArg( $this->escapeMagickOutput( $dstPath ) ) . " 2>&1";
 164                         wfDebug( __METHOD__.": running ImageMagick: $cmd\n" );
 165                         wfProfileIn( 'convert' );
 166                         $err = wfShellExec( $cmd, $retval );
 167                         wfProfileOut( 'convert' );
 168                 } elseif( $scaler == 'custom' ) {
 169                         # Use a custom convert command
 170                         # Variables: %s %d %w %h
 171                         $src = wfEscapeShellArg( $srcPath );
 172                         $dst = wfEscapeShellArg( $dstPath );
 173                         $cmd = $wgCustomConvertCommand;
 174                         $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 175                         $cmd = str_replace( '%h', $physicalHeight, str_replace( '%w', $physicalWidth, $cmd ) ); # Size
 176                         wfDebug( __METHOD__.": Running custom convert command $cmd\n" );
 177                         wfProfileIn( 'convert' );
 178                         $err = wfShellExec( $cmd, $retval );
 179                         wfProfileOut( 'convert' );
 180                 } else /* $scaler == 'gd' */ {
 181                         # Use PHP's builtin GD library functions.
 182                         #
 183                         # First find out what kind of file this is, and select the correct
 184                         # input routine for this.
 185
 186                         $typemap = array(
 187                                 'image/gif'          => array( 'imagecreatefromgif',  'palette',   'imagegif'  ),
 188                                 'image/jpeg'         => array( 'imagecreatefromjpeg', 'truecolor', array( __CLASS__, 'imageJpegWrapper' ) ),
 189                                 'image/png'          => array( 'imagecreatefrompng',  'bits',      'imagepng'  ),
 190                                 'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette',   'imagewbmp'  ),
 191                                 'image/xbm'          => array( 'imagecreatefromxbm',  'palette',   'imagexbm'  ),
 192                         );
 193                         if( !isset( $typemap[$mimeType] ) ) {
 194                                 $err = 'Image type not supported';
 195                                 wfDebug( "$err\n" );
 196                                 $errMsg = wfMsg ( 'thumbnail_image-type' );
 197                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 198                         }
 199                         list( $loader, $colorStyle, $saveType ) = $typemap[$mimeType];
 200
 201                         if( !function_exists( $loader ) ) {
 202                                 $err = "Incomplete GD library configuration: missing function $loader";
 203                                 wfDebug( "$err\n" );
 204                                 $errMsg = wfMsg ( 'thumbnail_gd-library', $loader );
 205                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 206                         }
 207
 208                         if ( !file_exists( $srcPath ) ) {
 209                                 $err = "File seems to be missing: $srcPath";
 210                                 wfDebug( "$err\n" );
 211                                 $errMsg = wfMsg ( 'thumbnail_image-missing', $srcPath );
 212                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 213                         }
 214
 215                         $src_image = call_user_func( $loader, $srcPath );
 216                         $dst_image = imagecreatetruecolor( $physicalWidth, $physicalHeight );
 217
 218                         // Initialise the destination image to transparent instead of
 219                         // the default solid black, to support PNG and GIF transparency nicely
 220                         $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 221                         imagecolortransparent( $dst_image, $background );
 222                         imagealphablending( $dst_image, false );
 223
 224                         if( $colorStyle == 'palette' ) {
 225                                 // Don't resample for paletted GIF images.
 226                                 // It may just uglify them, and completely breaks transparency.
 227                                 imagecopyresized( $dst_image, $src_image,
 228                                         0,0,0,0,
 229                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 230                         } else {
 231                                 imagecopyresampled( $dst_image, $src_image,
 232                                         0,0,0,0,
 233                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 234                         }
 235
 236                         imagesavealpha( $dst_image, true );
 237
 238                         call_user_func( $saveType, $dst_image, $dstPath );
 239                         imagedestroy( $dst_image );
 240                         imagedestroy( $src_image );
 241                         $retval = 0;
 242                 }
 243
 244                 $removed = $this->removeBadFile( $dstPath, $retval );
 245                 if ( $retval != 0 || $removed ) {
 246                         wfDebugLog( 'thumbnail',
 247                                 sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 248                                         wfHostname(), $retval, trim($err), $cmd ) );
 249                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 250                 } else {
 251                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 252                 }
 253         }
 254
 255         /**
 256          * Escape a string for ImageMagick's property input (e.g. -set -comment)
 257          * See InterpretImageProperties() in magick/property.c
 258          */
 259         function escapeMagickProperty( $s ) {
 260                 // Double the backslashes
 261                 $s = str_replace( '\\', '\\\\', $s );
 262                 // Double the percents
 263                 $s = str_replace( '%', '%%', $s );
 264                 // Escape initial - or @
 265                 if ( strlen( $s ) > 0 && ( $s[0] === '-' || $s[0] === '@' ) ) {
 266                         $s = '\\' . $s;
 267                 }
 268                 return $s;
 269         }
 270
 271         /**
 272          * Escape a string for ImageMagick's input filenames. See ExpandFilenames()
 273          * and GetPathComponent() in magick/utility.c.
 274          *
 275          * This won't work with an initial ~ or @, so input files should be prefixed
 276          * with the directory name.
 277          *
 278          * Glob character unescaping is broken in ImageMagick before 6.6.1-5, but
 279          * it's broken in a way that doesn't involve trying to convert every file
 280          * in a directory, so we're better off escaping and waiting for the bugfix
 281          * to filter down to users.
 282          *
 283          * @param $path string The file path
 284          * @param $scene string The scene specification, or false if there is none
 285          */
 286         function escapeMagickInput( $path, $scene = false ) {
 287                 # Die on initial metacharacters (caller should prepend path)
 288                 $firstChar = substr( $path, 0, 1 );
 289                 if ( $firstChar === '~' || $firstChar === '@' ) {
 290                         throw new MWException( __METHOD__.': cannot escape this path name' );
 291                 }
 292
 293                 # Escape glob chars
 294                 $path = preg_replace( '/[*?\[\]{}]/', '\\\\\0', $path );
 295
 296                 return $this->escapeMagickPath( $path, $scene );
 297         }
 298
 299         /**
 300          * Escape a string for ImageMagick's output filename. See
 301          * InterpretImageFilename() in magick/image.c.
 302          */
 303         function escapeMagickOutput( $path, $scene = false ) {
 304                 $path = str_replace( '%', '%%', $path );
 305                 return $this->escapeMagickPath( $path, $scene );
 306         }
 307
 308         /**
 309          * Armour a string against ImageMagick's GetPathComponent(). This is a
 310          * helper function for escapeMagickInput() and escapeMagickOutput().
 311          *
 312          * @param $path string The file path
 313          * @param $scene string The scene specification, or false if there is none
 314          */
 315         protected function escapeMagickPath( $path, $scene = false ) {
 316                 # Die on format specifiers (other than drive letters). The regex is
 317                 # meant to match all the formats you get from "convert -list format"
 318                 if ( preg_match( '/^([a-zA-Z0-9-]+):/', $path, $m ) ) {
 319                         if ( wfIsWindows() && is_dir( $m[0] ) ) {
 320                                 // OK, it's a drive letter
 321                                 // ImageMagick has a similar exception, see IsMagickConflict()
 322                         } else {
 323                                 throw new MWException( __METHOD__.': unexpected colon character in path name' );
 324                         }
 325                 }
 326
 327                 # If there are square brackets, add a do-nothing scene specification
 328                 # to force a literal interpretation
 329                 if ( $scene === false ) {
 330                         if ( strpos( $path, '[' ) !== false ) {
 331                                 $path .= '[0--1]';
 332                         }
 333                 } else {
 334                         $path .= "[$scene]";
 335                 }
 336                 return $path;
 337         }
 338
 339         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 340                 imageinterlace( $dst_image );
 341                 imagejpeg( $dst_image, $thumbPath, 95 );
 342         }
 343
 344
 345         function getMetadata( $image, $filename ) {
 346                 global $wgShowEXIF;
 347                 if( $wgShowEXIF && file_exists( $filename ) ) {
 348                         $exif = new Exif( $filename );
 349                         $data = $exif->getFilteredData();
 350                         if ( $data ) {
 351                                 $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 352                                 return serialize( $data );
 353                         } else {
 354                                 return '0';
 355                         }
 356                 } else {
 357                         return '';
 358                 }
 359         }
 360
 361         function getMetadataType( $image ) {
 362                 return 'exif';
 363         }
 364
 365         function isMetadataValid( $image, $metadata ) {
 366                 global $wgShowEXIF;
 367                 if ( !$wgShowEXIF ) {
 368                         # Metadata disabled and so an empty field is expected
 369                         return true;
 370                 }
 371                 if ( $metadata === '0' ) {
 372                         # Special value indicating that there is no EXIF data in the file
 373                         return true;
 374                 }
 375                 $exif = @unserialize( $metadata );
 376                 if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
 377                         $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
 378                 {
 379                         # Wrong version
 380                         wfDebug( __METHOD__.": wrong version\n" );
 381                         return false;
 382                 }
 383                 return true;
 384         }
 385
 386         /**
 387          * Get a list of EXIF metadata items which should be displayed when
 388          * the metadata table is collapsed.
 389          *
 390          * @return array of strings
 391          * @access private
 392          */
 393         function visibleMetadataFields() {
 394                 $fields = array();
 395                 $lines = explode( "\n", wfMsgForContent( 'metadata-fields' ) );
 396                 foreach( $lines as $line ) {
 397                         $matches = array();
 398                         if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
 399                                 $fields[] = $matches[1];
 400                         }
 401                 }
 402                 $fields = array_map( 'strtolower', $fields );
 403                 return $fields;
 404         }
 405
 406         function formatMetadata( $image ) {
 407                 $result = array(
 408                         'visible' => array(),
 409                         'collapsed' => array()
 410                 );
 411                 $metadata = $image->getMetadata();
 412                 if ( !$metadata ) {
 413                         return false;
 414                 }
 415                 $exif = unserialize( $metadata );
 416                 if ( !$exif ) {
 417                         return false;
 418                 }
 419                 unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
 420                 $format = new FormatExif( $exif );
 421
 422                 $formatted = $format->getFormattedData();
 423                 // Sort fields into visible and collapsed
 424                 $visibleFields = $this->visibleMetadataFields();
 425                 foreach ( $formatted as $name => $value ) {
 426                         $tag = strtolower( $name );
 427                         self::addMeta( $result,
 428                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 429                                 'exif',
 430                                 $tag,
 431                                 $value
 432                         );
 433                 }
 434                 return $result;
 435         }
 436 }