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                         // Use one thread only, to avoid deadlock bugs on OOM
 151                         $tempEnv = 'OMP_NUM_THREADS=1 ';
 152                         if ( strval( $wgImageMagickTempDir ) !== '' ) {
 153                                 $tempEnv .= 'MAGICK_TMPDIR=' . wfEscapeShellArg( $wgImageMagickTempDir ) . ' ';
 154                         }
 155
 156                         $cmd  =
 157                                 wfEscapeShellArg( $wgImageMagickConvertCommand ) .
 158                                 // Specify white background color, will be used for transparent images
 159                                 // in Internet Explorer/Windows instead of default black.
 160                                 " {$quality} -background white".
 161                                 " {$decoderHint} " .
 162                                 wfEscapeShellArg( $this->escapeMagickInput( $srcPath, $scene ) ) .
 163                                 " {$animation_pre}" .
 164                                 // For the -thumbnail option a "!" is needed to force exact size,
 165                                 // or ImageMagick may decide your ratio is wrong and slice off
 166                                 // a pixel.
 167                                 " -thumbnail " . wfEscapeShellArg( "{$physicalWidth}x{$physicalHeight}!" ) .
 168                                 // Add the source url as a comment to the thumb.
 169                                 " -set comment " . wfEscapeShellArg( $this->escapeMagickProperty( $comment ) ) .
 170                                 " -depth 8 $sharpen" .
 171                                 " {$animation_post} " .
 172                                 wfEscapeShellArg( $this->escapeMagickOutput( $dstPath ) ) . " 2>&1";
 173
 174                         if ( !wfIsWindows() ) {
 175                                 // Assume we have a POSIX compliant shell which accepts variable assignments preceding the command
 176                                 $cmd = $tempEnv . $cmd;
 177                         }
 178
 179                         wfDebug( __METHOD__.": running ImageMagick: $cmd\n" );
 180                         wfProfileIn( 'convert' );
 181                         $err = wfShellExec( $cmd, $retval );
 182                         wfProfileOut( 'convert' );
 183                 } elseif( $scaler == 'custom' ) {
 184                         # Use a custom convert command
 185                         # Variables: %s %d %w %h
 186                         $src = wfEscapeShellArg( $srcPath );
 187                         $dst = wfEscapeShellArg( $dstPath );
 188                         $cmd = $wgCustomConvertCommand;
 189                         $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 190                         $cmd = str_replace( '%h', $physicalHeight, str_replace( '%w', $physicalWidth, $cmd ) ); # Size
 191                         wfDebug( __METHOD__.": Running custom convert command $cmd\n" );
 192                         wfProfileIn( 'convert' );
 193                         $err = wfShellExec( $cmd, $retval );
 194                         wfProfileOut( 'convert' );
 195                 } else /* $scaler == 'gd' */ {
 196                         # Use PHP's builtin GD library functions.
 197                         #
 198                         # First find out what kind of file this is, and select the correct
 199                         # input routine for this.
 200
 201                         $typemap = array(
 202                                 'image/gif'          => array( 'imagecreatefromgif',  'palette',   'imagegif'  ),
 203                                 'image/jpeg'         => array( 'imagecreatefromjpeg', 'truecolor', array( __CLASS__, 'imageJpegWrapper' ) ),
 204                                 'image/png'          => array( 'imagecreatefrompng',  'bits',      'imagepng'  ),
 205                                 'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette',   'imagewbmp'  ),
 206                                 'image/xbm'          => array( 'imagecreatefromxbm',  'palette',   'imagexbm'  ),
 207                         );
 208                         if( !isset( $typemap[$mimeType] ) ) {
 209                                 $err = 'Image type not supported';
 210                                 wfDebug( "$err\n" );
 211                                 $errMsg = wfMsg ( 'thumbnail_image-type' );
 212                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 213                         }
 214                         list( $loader, $colorStyle, $saveType ) = $typemap[$mimeType];
 215
 216                         if( !function_exists( $loader ) ) {
 217                                 $err = "Incomplete GD library configuration: missing function $loader";
 218                                 wfDebug( "$err\n" );
 219                                 $errMsg = wfMsg ( 'thumbnail_gd-library', $loader );
 220                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 221                         }
 222
 223                         if ( !file_exists( $srcPath ) ) {
 224                                 $err = "File seems to be missing: $srcPath";
 225                                 wfDebug( "$err\n" );
 226                                 $errMsg = wfMsg ( 'thumbnail_image-missing', $srcPath );
 227                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $errMsg );
 228                         }
 229
 230                         $src_image = call_user_func( $loader, $srcPath );
 231                         $dst_image = imagecreatetruecolor( $physicalWidth, $physicalHeight );
 232
 233                         // Initialise the destination image to transparent instead of
 234                         // the default solid black, to support PNG and GIF transparency nicely
 235                         $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 236                         imagecolortransparent( $dst_image, $background );
 237                         imagealphablending( $dst_image, false );
 238
 239                         if( $colorStyle == 'palette' ) {
 240                                 // Don't resample for paletted GIF images.
 241                                 // It may just uglify them, and completely breaks transparency.
 242                                 imagecopyresized( $dst_image, $src_image,
 243                                         0,0,0,0,
 244                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 245                         } else {
 246                                 imagecopyresampled( $dst_image, $src_image,
 247                                         0,0,0,0,
 248                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 249                         }
 250
 251                         imagesavealpha( $dst_image, true );
 252
 253                         call_user_func( $saveType, $dst_image, $dstPath );
 254                         imagedestroy( $dst_image );
 255                         imagedestroy( $src_image );
 256                         $retval = 0;
 257                 }
 258
 259                 $removed = $this->removeBadFile( $dstPath, $retval );
 260                 if ( $retval != 0 || $removed ) {
 261                         wfDebugLog( 'thumbnail',
 262                                 sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 263                                         wfHostname(), $retval, trim($err), $cmd ) );
 264                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 265                 } else {
 266                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 267                 }
 268         }
 269
 270         /**
 271          * Escape a string for ImageMagick's property input (e.g. -set -comment)
 272          * See InterpretImageProperties() in magick/property.c
 273          */
 274         function escapeMagickProperty( $s ) {
 275                 // Double the backslashes
 276                 $s = str_replace( '\\', '\\\\', $s );
 277                 // Double the percents
 278                 $s = str_replace( '%', '%%', $s );
 279                 // Escape initial - or @
 280                 if ( strlen( $s ) > 0 && ( $s[0] === '-' || $s[0] === '@' ) ) {
 281                         $s = '\\' . $s;
 282                 }
 283                 return $s;
 284         }
 285
 286         /**
 287          * Escape a string for ImageMagick's input filenames. See ExpandFilenames()
 288          * and GetPathComponent() in magick/utility.c.
 289          *
 290          * This won't work with an initial ~ or @, so input files should be prefixed
 291          * with the directory name.
 292          *
 293          * Glob character unescaping is broken in ImageMagick before 6.6.1-5, but
 294          * it's broken in a way that doesn't involve trying to convert every file
 295          * in a directory, so we're better off escaping and waiting for the bugfix
 296          * to filter down to users.
 297          *
 298          * @param $path string The file path
 299          * @param $scene string The scene specification, or false if there is none
 300          */
 301         function escapeMagickInput( $path, $scene = false ) {
 302                 # Die on initial metacharacters (caller should prepend path)
 303                 $firstChar = substr( $path, 0, 1 );
 304                 if ( $firstChar === '~' || $firstChar === '@' ) {
 305                         throw new MWException( __METHOD__.': cannot escape this path name' );
 306                 }
 307
 308                 # Escape glob chars
 309                 $path = preg_replace( '/[*?\[\]{}]/', '\\\\\0', $path );
 310
 311                 return $this->escapeMagickPath( $path, $scene );
 312         }
 313
 314         /**
 315          * Escape a string for ImageMagick's output filename. See
 316          * InterpretImageFilename() in magick/image.c.
 317          */
 318         function escapeMagickOutput( $path, $scene = false ) {
 319                 $path = str_replace( '%', '%%', $path );
 320                 return $this->escapeMagickPath( $path, $scene );
 321         }
 322
 323         /**
 324          * Armour a string against ImageMagick's GetPathComponent(). This is a
 325          * helper function for escapeMagickInput() and escapeMagickOutput().
 326          *
 327          * @param $path string The file path
 328          * @param $scene string The scene specification, or false if there is none
 329          */
 330         protected function escapeMagickPath( $path, $scene = false ) {
 331                 # Die on format specifiers (other than drive letters). The regex is
 332                 # meant to match all the formats you get from "convert -list format"
 333                 if ( preg_match( '/^([a-zA-Z0-9-]+):/', $path, $m ) ) {
 334                         if ( wfIsWindows() && is_dir( $m[0] ) ) {
 335                                 // OK, it's a drive letter
 336                                 // ImageMagick has a similar exception, see IsMagickConflict()
 337                         } else {
 338                                 throw new MWException( __METHOD__.': unexpected colon character in path name' );
 339                         }
 340                 }
 341
 342                 # If there are square brackets, add a do-nothing scene specification
 343                 # to force a literal interpretation
 344                 if ( $scene === false ) {
 345                         if ( strpos( $path, '[' ) !== false ) {
 346                                 $path .= '[0--1]';
 347                         }
 348                 } else {
 349                         $path .= "[$scene]";
 350                 }
 351                 return $path;
 352         }
 353
 354         /**
 355          * Retrieve the version of the installed ImageMagick
 356          * You can use PHPs version_compare() to use this value
 357          * Value is cached for one hour.
 358          * @return String representing the IM version.
 359          */
 360         protected function getMagickVersion() {
 361                 global $wgMemc;
 362
 363                 $cache = $wgMemc->get( "imagemagick-version" );
 364                 if( !$cache ) {
 365                         global $wgImageMagickConvertCommand;
 366                         $cmd = wfEscapeShellArg( $wgImageMagickConvertCommand ) . ' -version';
 367                         wfDebug( __METHOD__.": Running convert -version\n" );
 368                         $retval = '';
 369                         $return = wfShellExec( $cmd, $retval );
 370                         $x = preg_match('/Version: ImageMagick ([0-9]*\.[0-9]*\.[0-9]*)/', $return, $matches);
 371                         if( $x != 1 ) {
 372                                 wfDebug( __METHOD__.": ImageMagick version check failed\n" );
 373                                 return null;
 374                         }
 375                         $wgMemc->set( "imagemagick-version", $matches[1], 3600 );
 376                         return $matches[1];
 377                 }
 378                 return $cache;
 379         }
 380
 381         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 382                 imageinterlace( $dst_image );
 383                 imagejpeg( $dst_image, $thumbPath, 95 );
 384         }
 385
 386
 387         function getMetadata( $image, $filename ) {
 388                 global $wgShowEXIF;
 389                 if( $wgShowEXIF && file_exists( $filename ) ) {
 390                         $exif = new Exif( $filename );
 391                         $data = $exif->getFilteredData();
 392                         if ( $data ) {
 393                                 $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 394                                 return serialize( $data );
 395                         } else {
 396                                 return '0';
 397                         }
 398                 } else {
 399                         return '';
 400                 }
 401         }
 402
 403         function getMetadataType( $image ) {
 404                 return 'exif';
 405         }
 406
 407         function isMetadataValid( $image, $metadata ) {
 408                 global $wgShowEXIF;
 409                 if ( !$wgShowEXIF ) {
 410                         # Metadata disabled and so an empty field is expected
 411                         return true;
 412                 }
 413                 if ( $metadata === '0' ) {
 414                         # Special value indicating that there is no EXIF data in the file
 415                         return true;
 416                 }
 417                 wfSuppressWarnings();
 418                 $exif = unserialize( $metadata );
 419                 wfRestoreWarnings();
 420                 if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
 421                         $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
 422                 {
 423                         # Wrong version
 424                         wfDebug( __METHOD__.": wrong version\n" );
 425                         return false;
 426                 }
 427                 return true;
 428         }
 429
 430         /**
 431          * Get a list of EXIF metadata items which should be displayed when
 432          * the metadata table is collapsed.
 433          *
 434          * @return array of strings
 435          * @access private
 436          */
 437         function visibleMetadataFields() {
 438                 $fields = array();
 439                 $lines = explode( "\n", wfMsgForContent( 'metadata-fields' ) );
 440                 foreach( $lines as $line ) {
 441                         $matches = array();
 442                         if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
 443                                 $fields[] = $matches[1];
 444                         }
 445                 }
 446                 $fields = array_map( 'strtolower', $fields );
 447                 return $fields;
 448         }
 449
 450         function formatMetadata( $image ) {
 451                 $result = array(
 452                         'visible' => array(),
 453                         'collapsed' => array()
 454                 );
 455                 $metadata = $image->getMetadata();
 456                 if ( !$metadata ) {
 457                         return false;
 458                 }
 459                 $exif = unserialize( $metadata );
 460                 if ( !$exif ) {
 461                         return false;
 462                 }
 463                 unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
 464                 $format = new FormatExif( $exif );
 465
 466                 $formatted = $format->getFormattedData();
 467                 // Sort fields into visible and collapsed
 468                 $visibleFields = $this->visibleMetadataFields();
 469                 foreach ( $formatted as $name => $value ) {
 470                         $tag = strtolower( $name );
 471                         self::addMeta( $result,
 472                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 473                                 'exif',
 474                                 $tag,
 475                                 $value
 476                         );
 477                 }
 478                 return $result;
 479         }
 480 }