includes/media/Bitmap.php

   1 <?php
   2 /**
   3  * Generic handler for bitmap images
   4  *
   5  * @file
   6  * @ingroup Media
   7  */
   8
   9 /**
  10  * Generic handler for bitmap images
  11  *
  12  * @ingroup Media
  13  */
  14 class BitmapHandler extends ImageHandler {
  15         function normaliseParams( $image, &$params ) {
  16                 global $wgMaxImageArea;
  17                 if ( !parent::normaliseParams( $image, $params ) ) {
  18                         return false;
  19                 }
  20
  21                 $mimeType = $image->getMimeType();
  22                 $srcWidth = $image->getWidth( $params['page'] );
  23                 $srcHeight = $image->getHeight( $params['page'] );
  24
  25                 # Don't make an image bigger than the source
  26                 $params['physicalWidth'] = $params['width'];
  27                 $params['physicalHeight'] = $params['height'];
  28
  29                 if ( $params['physicalWidth'] >= $srcWidth ) {
  30                         $params['physicalWidth'] = $srcWidth;
  31                         $params['physicalHeight'] = $srcHeight;
  32                         # Skip scaling limit checks if no scaling is required
  33                         if( !$image->mustRender() )
  34                                 return true;
  35                 }
  36
  37                 # Don't thumbnail an image so big that it will fill hard drives and send servers into swap
  38                 # JPEG has the handy property of allowing thumbnailing without full decompression, so we make
  39                 # an exception for it.
  40                 if ( $mimeType !== 'image/jpeg' &&
  41                         $srcWidth * $srcHeight > $wgMaxImageArea )
  42                 {
  43                         return false;
  44                 }
  45
  46                 return true;
  47         }
  48
  49
  50         // Function that returns the number of pixels to be thumbnailed.
  51         // Intended for animated GIFs to multiply by the number of frames.
  52         function getImageArea( $image, $width, $height ) {
  53                 return $width * $height;
  54         }
  55
  56         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
  57                 global $wgUseImageMagick, $wgImageMagickConvertCommand, $wgImageMagickTempDir;
  58                 global $wgCustomConvertCommand, $wgUseImageResize;
  59                 global $wgSharpenParameter, $wgSharpenReductionThreshold;
  60                 global $wgMaxAnimatedGifArea;
  61
  62                 if ( !$this->normaliseParams( $image, $params ) ) {
  63                         return new TransformParameterError( $params );
  64                 }
  65                 $physicalWidth = $params['physicalWidth'];
  66                 $physicalHeight = $params['physicalHeight'];
  67                 $clientWidth = $params['width'];
  68                 $clientHeight = $params['height'];
  69                 $comment = isset( $params['descriptionUrl'] ) ? "File source: ". $params['descriptionUrl'] : '';
  70                 $srcWidth = $image->getWidth();
  71                 $srcHeight = $image->getHeight();
  72                 $mimeType = $image->getMimeType();
  73                 $srcPath = $image->getPath();
  74                 $retval = 0;
  75                 wfDebug( __METHOD__.": creating {$physicalWidth}x{$physicalHeight} thumbnail at $dstPath\n" );
  76
  77                 if ( !$image->mustRender() && $physicalWidth == $srcWidth && $physicalHeight == $srcHeight ) {
  78                         # normaliseParams (or the user) wants us to return the unscaled image
  79                         wfDebug( __METHOD__.": returning unscaled image\n" );
  80                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  81                 }
  82
  83                 if ( !$dstPath ) {
  84                         // No output path available, client side scaling only
  85                         $scaler = 'client';
  86                 } elseif( !$wgUseImageResize ) {
  87                         $scaler = 'client';
  88                 } elseif ( $wgUseImageMagick ) {
  89                         $scaler = 'im';
  90                 } elseif ( $wgCustomConvertCommand ) {
  91                         $scaler = 'custom';
  92                 } elseif ( function_exists( 'imagecreatetruecolor' ) ) {
  93                         $scaler = 'gd';
  94                 } else {
  95                         $scaler = 'client';
  96                 }
  97                 wfDebug( __METHOD__.": scaler $scaler\n" );
  98
  99                 if ( $scaler == 'client' ) {
 100                         # Client-side image scaling, use the source URL
 101                         # Using the destination URL in a TRANSFORM_LATER request would be incorrect
 102                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
 103                 }
 104
 105                 if ( $flags & self::TRANSFORM_LATER ) {
 106                         wfDebug( __METHOD__.": Transforming later per flags.\n" );
 107                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 108                 }
 109
 110                 if ( !wfMkdirParents( dirname( $dstPath ) ) ) {
 111                         wfDebug( __METHOD__.": Unable to create thumbnail destination directory, falling back to client scaling\n" );
 112                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
 113                 }
 114
 115                 if ( $scaler == 'im' ) {
 116                         # use ImageMagick
 117
 118                         $quality = '';
 119                         $sharpen = '';
 120                         $scene = false;
 121                         $animation_pre = '';
 122                         $animation_post = '';
 123                         $decoderHint = '';
 124                         if ( $mimeType == 'image/jpeg' ) {
 125                                 $quality = "-quality 80"; // 80%
 126                                 # Sharpening, see bug 6193
 127                                 if ( ( $physicalWidth + $physicalHeight ) / ( $srcWidth + $srcHeight ) < $wgSharpenReductionThreshold ) {
 128                                         $sharpen = "-sharpen " . wfEscapeShellArg( $wgSharpenParameter );
 129                                 }
 130                                 // JPEG decoder hint to reduce memory, available since IM 6.5.6-2
 131                                 $decoderHint = "-define jpeg:size={$physicalWidth}x{$physicalHeight}";
 132                         } elseif ( $mimeType == 'image/png' ) {
 133                                 $quality = "-quality 95"; // zlib 9, adaptive filtering
 134                         } elseif( $mimeType == 'image/gif' ) {
 135                                 if( $this->getImageArea( $image, $srcWidth, $srcHeight ) > $wgMaxAnimatedGifArea ) {
 136                                         // Extract initial frame only; we're so big it'll
 137                                         // be a total drag. :P
 138                                         $scene = 0;
 139                                 } elseif( $this->isAnimatedImage( $image ) ) {
 140                                         // Coalesce is needed to scale animated GIFs properly (bug 1017).
 141                                         $animation_pre = '-coalesce';
 142                                         // We optimize the output, but -optimize is broken,
 143                                         // use optimizeTransparency instead (bug 11822)
 144                                         if( version_compare( $this->getMagickVersion(), "6.3.5" ) >= 0 ) {
 145                                                 $animation_post = '-fuzz 5% -layers optimizeTransparency +map';
 146                                         }
 147                                 }
 148                         }
 149
 150                         if ( strval( $wgImageMagickTempDir ) !== '' ) {
 151                                 $tempEnv = 'MAGICK_TMPDIR=' . wfEscapeShellArg( $wgImageMagickTempDir ) . ' ';
 152                         } else {
 153                                 $tempEnv = '';
 154                         }
 155
 156                         $cmd  =
 157                                 $tempEnv .
 158                                 // Use one thread only, to avoid deadlock bugs on OOM
 159                                 'OMP_NUM_THREADS=1 ' .
 160                                 wfEscapeShellArg( $wgImageMagickConvertCommand ) .
 161                                 // Specify white background color, will be used for transparent images
 162                                 // in Internet Explorer/Windows instead of default black.
 163                                 " {$quality} -background white".
 164                                 " {$decoderHint} " .
 165                                 wfEscapeShellArg( $this->escapeMagickInput( $srcPath, $scene ) ) .
 166                                 " {$animation_pre}" .
 167                                 // For the -thumbnail option a "!" is needed to force exact size,
 168                                 // or ImageMagick may decide your ratio is wrong and slice off
 169                                 // a pixel.
 170                                 " -thumbnail " . wfEscapeShellArg( "{$physicalWidth}x{$physicalHeight}!" ) .
 171                                 // Add the source url as a comment to the thumb.
 172                                 " -set comment " . wfEscapeShellArg( $this->escapeMagickProperty( $comment ) ) .
 173                                 " -depth 8 $sharpen" .
 174                                 " {$animation_post} " .
 175                                 wfEscapeShellArg( $this->escapeMagickOutput( $dstPath ) ) . " 2>&1";
 176                         wfDebug( __METHOD__.": running ImageMagick: $cmd\n" );
 177                         wfProfileIn( 'convert' );
 178                         $err = wfShellExec( $cmd, $retval );
 179                         wfProfileOut( 'convert' );
 180                 } elseif( $scaler == 'custom' ) {
 181                         # Use a custom convert command
 182                         # Variables: %s %d %w %h
 183                         $src = wfEscapeShellArg( $srcPath );
 184                         $dst = wfEscapeShellArg( $dstPath );
 185                         $cmd = $wgCustomConvertCommand;
 186                         $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 187                         $cmd = str_replace( '%h', $physicalHeight, str_replace( '%w', $physicalWidth, $cmd ) ); # Size
 188                         wfDebug( __METHOD__.": Running custom convert command $cmd\n" );
 189                         wfProfileIn( 'convert' );
 190                         $err = wfShellExec( $cmd, $retval );
 191                         wfProfileOut( 'convert' );
 192                 } else /* $scaler == 'gd' */ {
 193                         # Use PHP's builtin GD library functions.
 194                         #
 195                         # First find out what kind of file this is, and select the correct
 196                         # input routine for this.
 197
 198                         $typemap = array(
 199                                 'image/gif'          => array( 'imagecreatefromgif',  'palette',   'imagegif'  ),
 200                                 'image/jpeg'         => array( 'imagecreatefromjpeg', 'truecolor', array( __CLASS__, 'imageJpegWrapper' ) ),
 201                                 'image/png'          => array( 'imagecreatefrompng',  'bits',      'imagepng'  ),
 202                                 'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette',   'imagewbmp'  ),
 203                                 'image/xbm'          => array( 'imagecreatefromxbm',  'palette',   'imagexbm'  ),
 204                         );
 205                         if( !isset( $typemap[$mimeType] ) ) {
 206                                 $err = 'Image type not supported';
 207                                 wfDebug( "$err\n" );
 208                                 $errMsg = wfMsg ( 'thumbnail_image-type' );
 209                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 210                         }
 211                         list( $loader, $colorStyle, $saveType ) = $typemap[$mimeType];
 212
 213                         if( !function_exists( $loader ) ) {
 214                                 $err = "Incomplete GD library configuration: missing function $loader";
 215                                 wfDebug( "$err\n" );
 216                                 $errMsg = wfMsg ( 'thumbnail_gd-library', $loader );
 217                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 218                         }
 219
 220                         if ( !file_exists( $srcPath ) ) {
 221                                 $err = "File seems to be missing: $srcPath";
 222                                 wfDebug( "$err\n" );
 223                                 $errMsg = wfMsg ( 'thumbnail_image-missing', $srcPath );
 224                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 225                         }
 226
 227                         $src_image = call_user_func( $loader, $srcPath );
 228                         $dst_image = imagecreatetruecolor( $physicalWidth, $physicalHeight );
 229
 230                         // Initialise the destination image to transparent instead of
 231                         // the default solid black, to support PNG and GIF transparency nicely
 232                         $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 233                         imagecolortransparent( $dst_image, $background );
 234                         imagealphablending( $dst_image, false );
 235
 236                         if( $colorStyle == 'palette' ) {
 237                                 // Don't resample for paletted GIF images.
 238                                 // It may just uglify them, and completely breaks transparency.
 239                                 imagecopyresized( $dst_image, $src_image,
 240                                         0,0,0,0,
 241                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 242                         } else {
 243                                 imagecopyresampled( $dst_image, $src_image,
 244                                         0,0,0,0,
 245                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 246                         }
 247
 248                         imagesavealpha( $dst_image, true );
 249
 250                         call_user_func( $saveType, $dst_image, $dstPath );
 251                         imagedestroy( $dst_image );
 252                         imagedestroy( $src_image );
 253                         $retval = 0;
 254                 }
 255
 256                 $removed = $this->removeBadFile( $dstPath, $retval );
 257                 if ( $retval != 0 || $removed ) {
 258                         wfDebugLog( 'thumbnail',
 259                                 sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 260                                         wfHostname(), $retval, trim($err), $cmd ) );
 261                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 262                 } else {
 263                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 264                 }
 265         }
 266
 267         /**
 268          * Escape a string for ImageMagick's property input (e.g. -set -comment)
 269          * See InterpretImageProperties() in magick/property.c
 270          */
 271         function escapeMagickProperty( $s ) {
 272                 // Double the backslashes
 273                 $s = str_replace( '\\', '\\\\', $s );
 274                 // Double the percents
 275                 $s = str_replace( '%', '%%', $s );
 276                 // Escape initial - or @
 277                 if ( strlen( $s ) > 0 && ( $s[0] === '-' || $s[0] === '@' ) ) {
 278                         $s = '\\' . $s;
 279                 }
 280                 return $s;
 281         }
 282
 283         /**
 284          * Escape a string for ImageMagick's input filenames. See ExpandFilenames()
 285          * and GetPathComponent() in magick/utility.c.
 286          *
 287          * This won't work with an initial ~ or @, so input files should be prefixed
 288          * with the directory name.
 289          *
 290          * Glob character unescaping is broken in ImageMagick before 6.6.1-5, but
 291          * it's broken in a way that doesn't involve trying to convert every file
 292          * in a directory, so we're better off escaping and waiting for the bugfix
 293          * to filter down to users.
 294          *
 295          * @param $path string The file path
 296          * @param $scene string The scene specification, or false if there is none
 297          */
 298         function escapeMagickInput( $path, $scene = false ) {
 299                 # Die on initial metacharacters (caller should prepend path)
 300                 $firstChar = substr( $path, 0, 1 );
 301                 if ( $firstChar === '~' || $firstChar === '@' ) {
 302                         throw new MWException( __METHOD__.': cannot escape this path name' );
 303                 }
 304
 305                 # Escape glob chars
 306                 $path = preg_replace( '/[*?\[\]{}]/', '\\\\\0', $path );
 307
 308                 return $this->escapeMagickPath( $path, $scene );
 309         }
 310
 311         /**
 312          * Escape a string for ImageMagick's output filename. See
 313          * InterpretImageFilename() in magick/image.c.
 314          */
 315         function escapeMagickOutput( $path, $scene = false ) {
 316                 $path = str_replace( '%', '%%', $path );
 317                 return $this->escapeMagickPath( $path, $scene );
 318         }
 319
 320         /**
 321          * Armour a string against ImageMagick's GetPathComponent(). This is a
 322          * helper function for escapeMagickInput() and escapeMagickOutput().
 323          *
 324          * @param $path string The file path
 325          * @param $scene string The scene specification, or false if there is none
 326          */
 327         protected function escapeMagickPath( $path, $scene = false ) {
 328                 # Die on format specifiers (other than drive letters). The regex is
 329                 # meant to match all the formats you get from "convert -list format"
 330                 if ( preg_match( '/^([a-zA-Z0-9-]+):/', $path, $m ) ) {
 331                         if ( wfIsWindows() && is_dir( $m[0] ) ) {
 332                                 // OK, it's a drive letter
 333                                 // ImageMagick has a similar exception, see IsMagickConflict()
 334                         } else {
 335                                 throw new MWException( __METHOD__.': unexpected colon character in path name' );
 336                         }
 337                 }
 338
 339                 # If there are square brackets, add a do-nothing scene specification
 340                 # to force a literal interpretation
 341                 if ( $scene === false ) {
 342                         if ( strpos( $path, '[' ) !== false ) {
 343                                 $path .= '[0--1]';
 344                         }
 345                 } else {
 346                         $path .= "[$scene]";
 347                 }
 348                 return $path;
 349         }
 350
 351         /**
 352          * Retrieve the version of the installed ImageMagick
 353          * You can use PHPs version_compare() to use this value
 354          * Value is cached for one hour.
 355          * @return String representing the IM version.
 356          */
 357         protected function getMagickVersion() {
 358                 global $wgMemc;
 359
 360                 $cache = $wgMemc->get( "imagemagick-version" );
 361                 if( !$cache ) {
 362                         global $wgImageMagickConvertCommand;
 363                         $cmd = wfEscapeShellArg( $wgImageMagickConvertCommand ) . ' -version';
 364                         wfDebug( __METHOD__.": Running convert -version\n" );
 365                         $retval = '';
 366                         $return = wfShellExec( $cmd, &$retval );
 367                         $x = preg_match('/Version: ImageMagick ([0-9]*\.[0-9]*\.[0-9]*)/', $return, $matches);
 368                         if( $x != 1 ) {
 369                                 wfDebug( __METHOD__.": ImageMagick version check failed\n" );
 370                                 return null;
 371                         }
 372                         $wgMemc->set( "imagemagick-version", $matches[1], 3600 );
 373                         return $matches[1];
 374                 }
 375                 return $cache;
 376         }
 377
 378         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 379                 imageinterlace( $dst_image );
 380                 imagejpeg( $dst_image, $thumbPath, 95 );
 381         }
 382
 383
 384         function getMetadata( $image, $filename ) {
 385                 global $wgShowEXIF;
 386                 if( $wgShowEXIF && file_exists( $filename ) ) {
 387                         $exif = new Exif( $filename );
 388                         $data = $exif->getFilteredData();
 389                         if ( $data ) {
 390                                 $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 391                                 return serialize( $data );
 392                         } else {
 393                                 return '0';
 394                         }
 395                 } else {
 396                         return '';
 397                 }
 398         }
 399
 400         function getMetadataType( $image ) {
 401                 return 'exif';
 402         }
 403
 404         function isMetadataValid( $image, $metadata ) {
 405                 global $wgShowEXIF;
 406                 if ( !$wgShowEXIF ) {
 407                         # Metadata disabled and so an empty field is expected
 408                         return true;
 409                 }
 410                 if ( $metadata === '0' ) {
 411                         # Special value indicating that there is no EXIF data in the file
 412                         return true;
 413                 }
 414                 wfSuppressWarnings();
 415                 $exif = unserialize( $metadata );
 416                 wfRestoreWarnings();
 417                 if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
 418                         $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
 419                 {
 420                         # Wrong version
 421                         wfDebug( __METHOD__.": wrong version\n" );
 422                         return false;
 423                 }
 424                 return true;
 425         }
 426
 427         /**
 428          * Get a list of EXIF metadata items which should be displayed when
 429          * the metadata table is collapsed.
 430          *
 431          * @return array of strings
 432          * @access private
 433          */
 434         function visibleMetadataFields() {
 435                 $fields = array();
 436                 $lines = explode( "\n", wfMsgForContent( 'metadata-fields' ) );
 437                 foreach( $lines as $line ) {
 438                         $matches = array();
 439                         if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
 440                                 $fields[] = $matches[1];
 441                         }
 442                 }
 443                 $fields = array_map( 'strtolower', $fields );
 444                 return $fields;
 445         }
 446
 447         function formatMetadata( $image ) {
 448                 $result = array(
 449                         'visible' => array(),
 450                         'collapsed' => array()
 451                 );
 452                 $metadata = $image->getMetadata();
 453                 if ( !$metadata ) {
 454                         return false;
 455                 }
 456                 $exif = unserialize( $metadata );
 457                 if ( !$exif ) {
 458                         return false;
 459                 }
 460                 unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
 461                 $format = new FormatExif( $exif );
 462
 463                 $formatted = $format->getFormattedData();
 464                 // Sort fields into visible and collapsed
 465                 $visibleFields = $this->visibleMetadataFields();
 466                 foreach ( $formatted as $name => $value ) {
 467                         $tag = strtolower( $name );
 468                         self::addMeta( $result,
 469                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 470                                 'exif',
 471                                 $tag,
 472                                 $value
 473                         );
 474                 }
 475                 return $result;
 476         }
 477 }