includes/media/Bitmap.php

   1 <?php
   2 /**
   3  * Generic handler for bitmap images.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Media
  22  */
  23
  24 /**
  25  * Generic handler for bitmap images
  26  *
  27  * @ingroup Media
  28  */
  29 class BitmapHandler extends ImageHandler {
  30         /**
  31          * @param $image File
  32          * @param array $params Transform parameters. Entries with the keys 'width'
  33          * and 'height' are the respective screen width and height, while the keys
  34          * 'physicalWidth' and 'physicalHeight' indicate the thumbnail dimensions.
  35          * @return bool
  36          */
  37         function normaliseParams( $image, &$params ) {
  38                 if ( !parent::normaliseParams( $image, $params ) ) {
  39                         return false;
  40                 }
  41
  42                 # Obtain the source, pre-rotation dimensions
  43                 $srcWidth = $image->getWidth( $params['page'] );
  44                 $srcHeight = $image->getHeight( $params['page'] );
  45
  46                 # Don't make an image bigger than the source
  47                 if ( $params['physicalWidth'] >= $srcWidth ) {
  48                         $params['physicalWidth'] = $srcWidth;
  49                         $params['physicalHeight'] = $srcHeight;
  50
  51                         # Skip scaling limit checks if no scaling is required
  52                         # due to requested size being bigger than source.
  53                         if ( !$image->mustRender() ) {
  54                                 return true;
  55                         }
  56                 }
  57
  58                 # Check if the file is smaller than the maximum image area for thumbnailing
  59                 $checkImageAreaHookResult = null;
  60                 wfRunHooks(
  61                         'BitmapHandlerCheckImageArea',
  62                         array( $image, &$params, &$checkImageAreaHookResult )
  63                 );
  64
  65                 if ( is_null( $checkImageAreaHookResult ) ) {
  66                         global $wgMaxImageArea;
  67
  68                         if ( $srcWidth * $srcHeight > $wgMaxImageArea
  69                                 && !( $image->getMimeType() == 'image/jpeg'
  70                                 && self::getScalerType( false, false ) == 'im' )
  71                         ) {
  72                                 # Only ImageMagick can efficiently downsize jpg images without loading
  73                                 # the entire file in memory
  74                                 return false;
  75                         }
  76                 } else {
  77                         return $checkImageAreaHookResult;
  78                 }
  79
  80                 return true;
  81         }
  82
  83         /**
  84          * Extracts the width/height if the image will be scaled before rotating
  85          *
  86          * This will match the physical size/aspect ratio of the original image
  87          * prior to application of the rotation -- so for a portrait image that's
  88          * stored as raw landscape with 90-degress rotation, the resulting size
  89          * will be wider than it is tall.
  90          *
  91          * @param array $params Parameters as returned by normaliseParams
  92          * @param int $rotation The rotation angle that will be applied
  93          * @return array ($width, $height) array
  94          */
  95         public function extractPreRotationDimensions( $params, $rotation ) {
  96                 if ( $rotation == 90 || $rotation == 270 ) {
  97                         # We'll resize before rotation, so swap the dimensions again
  98                         $width = $params['physicalHeight'];
  99                         $height = $params['physicalWidth'];
 100                 } else {
 101                         $width = $params['physicalWidth'];
 102                         $height = $params['physicalHeight'];
 103                 }
 104
 105                 return array( $width, $height );
 106         }
 107
 108         /**
 109          * @param $image File
 110          * @param  $dstPath
 111          * @param  $dstUrl
 112          * @param  $params
 113          * @param int $flags
 114          * @return MediaTransformError|ThumbnailImage|TransformParameterError
 115          */
 116         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
 117                 if ( !$this->normaliseParams( $image, $params ) ) {
 118                         return new TransformParameterError( $params );
 119                 }
 120                 # Create a parameter array to pass to the scaler
 121                 $scalerParams = array(
 122                         # The size to which the image will be resized
 123                         'physicalWidth' => $params['physicalWidth'],
 124                         'physicalHeight' => $params['physicalHeight'],
 125                         'physicalDimensions' => "{$params['physicalWidth']}x{$params['physicalHeight']}",
 126                         # The size of the image on the page
 127                         'clientWidth' => $params['width'],
 128                         'clientHeight' => $params['height'],
 129                         # Comment as will be added to the Exif of the thumbnail
 130                         'comment' => isset( $params['descriptionUrl'] )
 131                                 ? "File source: {$params['descriptionUrl']}"
 132                                 : '',
 133                         # Properties of the original image
 134                         'srcWidth' => $image->getWidth(),
 135                         'srcHeight' => $image->getHeight(),
 136                         'mimeType' => $image->getMimeType(),
 137                         'dstPath' => $dstPath,
 138                         'dstUrl' => $dstUrl,
 139                 );
 140
 141                 # Determine scaler type
 142                 $scaler = self::getScalerType( $dstPath );
 143
 144                 wfDebug( __METHOD__ . ": creating {$scalerParams['physicalDimensions']} " .
 145                         "thumbnail at $dstPath using scaler $scaler\n" );
 146
 147                 if ( !$image->mustRender() &&
 148                         $scalerParams['physicalWidth'] == $scalerParams['srcWidth']
 149                         && $scalerParams['physicalHeight'] == $scalerParams['srcHeight']
 150                 ) {
 151
 152                         # normaliseParams (or the user) wants us to return the unscaled image
 153                         wfDebug( __METHOD__ . ": returning unscaled image\n" );
 154
 155                         return $this->getClientScalingThumbnailImage( $image, $scalerParams );
 156                 }
 157
 158                 if ( $scaler == 'client' ) {
 159                         # Client-side image scaling, use the source URL
 160                         # Using the destination URL in a TRANSFORM_LATER request would be incorrect
 161                         return $this->getClientScalingThumbnailImage( $image, $scalerParams );
 162                 }
 163
 164                 if ( $flags & self::TRANSFORM_LATER ) {
 165                         wfDebug( __METHOD__ . ": Transforming later per flags.\n" );
 166                         $params = array(
 167                                 'width' => $scalerParams['clientWidth'],
 168                                 'height' => $scalerParams['clientHeight']
 169                         );
 170
 171                         return new ThumbnailImage( $image, $dstUrl, false, $params );
 172                 }
 173
 174                 # Try to make a target path for the thumbnail
 175                 if ( !wfMkdirParents( dirname( $dstPath ), null, __METHOD__ ) ) {
 176                         wfDebug( __METHOD__ . ": Unable to create thumbnail destination " .
 177                                 "directory, falling back to client scaling\n" );
 178
 179                         return $this->getClientScalingThumbnailImage( $image, $scalerParams );
 180                 }
 181
 182                 # Transform functions and binaries need a FS source file
 183                 $scalerParams['srcPath'] = $image->getLocalRefPath();
 184                 if ( $scalerParams['srcPath'] === false ) { // Failed to get local copy
 185                         wfDebugLog( 'thumbnail',
 186                                 sprintf( 'Thumbnail failed on %s: could not get local copy of "%s"',
 187                                         wfHostname(), $image->getName() ) );
 188
 189                         return new MediaTransformError( 'thumbnail_error',
 190                                 $scalerParams['clientWidth'], $scalerParams['clientHeight'] );
 191                 }
 192
 193                 # Try a hook
 194                 $mto = null;
 195                 wfRunHooks( 'BitmapHandlerTransform', array( $this, $image, &$scalerParams, &$mto ) );
 196                 if ( !is_null( $mto ) ) {
 197                         wfDebug( __METHOD__ . ": Hook to BitmapHandlerTransform created an mto\n" );
 198                         $scaler = 'hookaborted';
 199                 }
 200
 201                 switch ( $scaler ) {
 202                         case 'hookaborted':
 203                                 # Handled by the hook above
 204                                 $err = $mto->isError() ? $mto : false;
 205                                 break;
 206                         case 'im':
 207                                 $err = $this->transformImageMagick( $image, $scalerParams );
 208                                 break;
 209                         case 'custom':
 210                                 $err = $this->transformCustom( $image, $scalerParams );
 211                                 break;
 212                         case 'imext':
 213                                 $err = $this->transformImageMagickExt( $image, $scalerParams );
 214                                 break;
 215                         case 'gd':
 216                         default:
 217                                 $err = $this->transformGd( $image, $scalerParams );
 218                                 break;
 219                 }
 220
 221                 # Remove the file if a zero-byte thumbnail was created, or if there was an error
 222                 $removed = $this->removeBadFile( $dstPath, (bool)$err );
 223                 if ( $err ) {
 224                         # transform returned MediaTransforError
 225                         return $err;
 226                 } elseif ( $removed ) {
 227                         # Thumbnail was zero-byte and had to be removed
 228                         return new MediaTransformError( 'thumbnail_error',
 229                                 $scalerParams['clientWidth'], $scalerParams['clientHeight'] );
 230                 } elseif ( $mto ) {
 231                         return $mto;
 232                 } else {
 233                         $params = array(
 234                                 'width' => $scalerParams['clientWidth'],
 235                                 'height' => $scalerParams['clientHeight']
 236                         );
 237
 238                         return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
 239                 }
 240         }
 241
 242         /**
 243          * Returns which scaler type should be used. Creates parent directories
 244          * for $dstPath and returns 'client' on error
 245          *
 246          * @return string client,im,custom,gd
 247          */
 248         protected static function getScalerType( $dstPath, $checkDstPath = true ) {
 249                 global $wgUseImageResize, $wgUseImageMagick, $wgCustomConvertCommand;
 250
 251                 if ( !$dstPath && $checkDstPath ) {
 252                         # No output path available, client side scaling only
 253                         $scaler = 'client';
 254                 } elseif ( !$wgUseImageResize ) {
 255                         $scaler = 'client';
 256                 } elseif ( $wgUseImageMagick ) {
 257                         $scaler = 'im';
 258                 } elseif ( $wgCustomConvertCommand ) {
 259                         $scaler = 'custom';
 260                 } elseif ( function_exists( 'imagecreatetruecolor' ) ) {
 261                         $scaler = 'gd';
 262                 } elseif ( class_exists( 'Imagick' ) ) {
 263                         $scaler = 'imext';
 264                 } else {
 265                         $scaler = 'client';
 266                 }
 267
 268                 return $scaler;
 269         }
 270
 271         /**
 272          * Get a ThumbnailImage that respresents an image that will be scaled
 273          * client side
 274          *
 275          * @param $image File File associated with this thumbnail
 276          * @param array $scalerParams Array with scaler params
 277          * @return ThumbnailImage
 278          *
 279          * @todo fixme: no rotation support
 280          */
 281         protected function getClientScalingThumbnailImage( $image, $scalerParams ) {
 282                 $params = array(
 283                         'width' => $scalerParams['clientWidth'],
 284                         'height' => $scalerParams['clientHeight']
 285                 );
 286
 287                 return new ThumbnailImage( $image, $image->getURL(), null, $params );
 288         }
 289
 290         /**
 291          * Transform an image using ImageMagick
 292          *
 293          * @param $image File File associated with this thumbnail
 294          * @param array $params Array with scaler params
 295          *
 296          * @return MediaTransformError Error object if error occurred, false (=no error) otherwise
 297          */
 298         protected function transformImageMagick( $image, $params ) {
 299                 # use ImageMagick
 300                 global $wgSharpenReductionThreshold, $wgSharpenParameter, $wgMaxAnimatedGifArea,
 301                         $wgImageMagickTempDir, $wgImageMagickConvertCommand;
 302
 303                 $quality = '';
 304                 $sharpen = '';
 305                 $scene = false;
 306                 $animation_pre = '';
 307                 $animation_post = '';
 308                 $decoderHint = '';
 309                 if ( $params['mimeType'] == 'image/jpeg' ) {
 310                         $quality = "-quality 80"; // 80%
 311                         # Sharpening, see bug 6193
 312                         if ( ( $params['physicalWidth'] + $params['physicalHeight'] )
 313                                 / ( $params['srcWidth'] + $params['srcHeight'] )
 314                                 < $wgSharpenReductionThreshold
 315                         ) {
 316                                 $sharpen = "-sharpen " . wfEscapeShellArg( $wgSharpenParameter );
 317                         }
 318                         if ( version_compare( $this->getMagickVersion(), "6.5.6" ) >= 0 ) {
 319                                 // JPEG decoder hint to reduce memory, available since IM 6.5.6-2
 320                                 $decoderHint = "-define jpeg:size={$params['physicalDimensions']}";
 321                         }
 322                 } elseif ( $params['mimeType'] == 'image/png' ) {
 323                         $quality = "-quality 95"; // zlib 9, adaptive filtering
 324
 325                 } elseif ( $params['mimeType'] == 'image/gif' ) {
 326                         if ( $this->getImageArea( $image ) > $wgMaxAnimatedGifArea ) {
 327                                 // Extract initial frame only; we're so big it'll
 328                                 // be a total drag. :P
 329                                 $scene = 0;
 330                         } elseif ( $this->isAnimatedImage( $image ) ) {
 331                                 // Coalesce is needed to scale animated GIFs properly (bug 1017).
 332                                 $animation_pre = '-coalesce';
 333                                 // We optimize the output, but -optimize is broken,
 334                                 // use optimizeTransparency instead (bug 11822)
 335                                 if ( version_compare( $this->getMagickVersion(), "6.3.5" ) >= 0 ) {
 336                                         $animation_post = '-fuzz 5% -layers optimizeTransparency';
 337                                 }
 338                         }
 339                 } elseif ( $params['mimeType'] == 'image/x-xcf' ) {
 340                         $animation_post = '-layers merge';
 341                 }
 342
 343                 // Use one thread only, to avoid deadlock bugs on OOM
 344                 $env = array( 'OMP_NUM_THREADS' => 1 );
 345                 if ( strval( $wgImageMagickTempDir ) !== '' ) {
 346                         $env['MAGICK_TMPDIR'] = $wgImageMagickTempDir;
 347                 }
 348
 349                 $rotation = $this->getRotation( $image );
 350                 list( $width, $height ) = $this->extractPreRotationDimensions( $params, $rotation );
 351
 352                 $cmd =
 353                         wfEscapeShellArg( $wgImageMagickConvertCommand ) .
 354                         // Specify white background color, will be used for transparent images
 355                         // in Internet Explorer/Windows instead of default black.
 356                         " {$quality} -background white" .
 357                         " {$decoderHint} " .
 358                         wfEscapeShellArg( $this->escapeMagickInput( $params['srcPath'], $scene ) ) .
 359                         " {$animation_pre}" .
 360                         // For the -thumbnail option a "!" is needed to force exact size,
 361                         // or ImageMagick may decide your ratio is wrong and slice off
 362                         // a pixel.
 363                         " -thumbnail " . wfEscapeShellArg( "{$width}x{$height}!" ) .
 364                         // Add the source url as a comment to the thumb, but don't add the flag if there's no comment
 365                         ( $params['comment'] !== ''
 366                                 ? " -set comment " . wfEscapeShellArg( $this->escapeMagickProperty( $params['comment'] ) )
 367                                 : '' ) .
 368                         " -depth 8 $sharpen " .
 369                         " -rotate -$rotation " .
 370                         " {$animation_post} " .
 371                         wfEscapeShellArg( $this->escapeMagickOutput( $params['dstPath'] ) );
 372
 373                 wfDebug( __METHOD__ . ": running ImageMagick: $cmd\n" );
 374                 wfProfileIn( 'convert' );
 375                 $retval = 0;
 376                 $err = wfShellExecWithStderr( $cmd, $retval, $env );
 377                 wfProfileOut( 'convert' );
 378
 379                 if ( $retval !== 0 ) {
 380                         $this->logErrorForExternalProcess( $retval, $err, $cmd );
 381
 382                         return $this->getMediaTransformError( $params, $err );
 383                 }
 384
 385                 return false; # No error
 386         }
 387
 388         /**
 389          * Transform an image using the Imagick PHP extension
 390          *
 391          * @param $image File File associated with this thumbnail
 392          * @param array $params Array with scaler params
 393          *
 394          * @return MediaTransformError Error object if error occurred, false (=no error) otherwise
 395          */
 396         protected function transformImageMagickExt( $image, $params ) {
 397                 global $wgSharpenReductionThreshold, $wgSharpenParameter, $wgMaxAnimatedGifArea;
 398
 399                 try {
 400                         $im = new Imagick();
 401                         $im->readImage( $params['srcPath'] );
 402
 403                         if ( $params['mimeType'] == 'image/jpeg' ) {
 404                                 // Sharpening, see bug 6193
 405                                 if ( ( $params['physicalWidth'] + $params['physicalHeight'] )
 406                                         / ( $params['srcWidth'] + $params['srcHeight'] )
 407                                         < $wgSharpenReductionThreshold
 408                                 ) {
 409                                         // Hack, since $wgSharpenParamater is written specifically for the command line convert
 410                                         list( $radius, $sigma ) = explode( 'x', $wgSharpenParameter );
 411                                         $im->sharpenImage( $radius, $sigma );
 412                                 }
 413                                 $im->setCompressionQuality( 80 );
 414                         } elseif ( $params['mimeType'] == 'image/png' ) {
 415                                 $im->setCompressionQuality( 95 );
 416                         } elseif ( $params['mimeType'] == 'image/gif' ) {
 417                                 if ( $this->getImageArea( $image ) > $wgMaxAnimatedGifArea ) {
 418                                         // Extract initial frame only; we're so big it'll
 419                                         // be a total drag. :P
 420                                         $im->setImageScene( 0 );
 421                                 } elseif ( $this->isAnimatedImage( $image ) ) {
 422                                         // Coalesce is needed to scale animated GIFs properly (bug 1017).
 423                                         $im = $im->coalesceImages();
 424                                 }
 425                         }
 426
 427                         $rotation = $this->getRotation( $image );
 428                         list( $width, $height ) = $this->extractPreRotationDimensions( $params, $rotation );
 429
 430                         $im->setImageBackgroundColor( new ImagickPixel( 'white' ) );
 431
 432                         // Call Imagick::thumbnailImage on each frame
 433                         foreach ( $im as $i => $frame ) {
 434                                 if ( !$frame->thumbnailImage( $width, $height, /* fit */ false ) ) {
 435                                         return $this->getMediaTransformError( $params, "Error scaling frame $i" );
 436                                 }
 437                         }
 438                         $im->setImageDepth( 8 );
 439
 440                         if ( $rotation ) {
 441                                 if ( !$im->rotateImage( new ImagickPixel( 'white' ), 360 - $rotation ) ) {
 442                                         return $this->getMediaTransformError( $params, "Error rotating $rotation degrees" );
 443                                 }
 444                         }
 445
 446                         if ( $this->isAnimatedImage( $image ) ) {
 447                                 wfDebug( __METHOD__ . ": Writing animated thumbnail\n" );
 448                                 // This is broken somehow... can't find out how to fix it
 449                                 $result = $im->writeImages( $params['dstPath'], true );
 450                         } else {
 451                                 $result = $im->writeImage( $params['dstPath'] );
 452                         }
 453                         if ( !$result ) {
 454                                 return $this->getMediaTransformError( $params,
 455                                         "Unable to write thumbnail to {$params['dstPath']}" );
 456                         }
 457                 } catch ( ImagickException $e ) {
 458                         return $this->getMediaTransformError( $params, $e->getMessage() );
 459                 }
 460
 461                 return false;
 462         }
 463
 464         /**
 465          * Transform an image using a custom command
 466          *
 467          * @param $image File File associated with this thumbnail
 468          * @param array $params Array with scaler params
 469          *
 470          * @return MediaTransformError Error object if error occurred, false (=no error) otherwise
 471          */
 472         protected function transformCustom( $image, $params ) {
 473                 # Use a custom convert command
 474                 global $wgCustomConvertCommand;
 475
 476                 # Variables: %s %d %w %h
 477                 $src = wfEscapeShellArg( $params['srcPath'] );
 478                 $dst = wfEscapeShellArg( $params['dstPath'] );
 479                 $cmd = $wgCustomConvertCommand;
 480                 $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 481                 $cmd = str_replace( '%h', $params['physicalHeight'],
 482                         str_replace( '%w', $params['physicalWidth'], $cmd ) ); # Size
 483                 wfDebug( __METHOD__ . ": Running custom convert command $cmd\n" );
 484                 wfProfileIn( 'convert' );
 485                 $retval = 0;
 486                 $err = wfShellExecWithStderr( $cmd, $retval );
 487                 wfProfileOut( 'convert' );
 488
 489                 if ( $retval !== 0 ) {
 490                         $this->logErrorForExternalProcess( $retval, $err, $cmd );
 491
 492                         return $this->getMediaTransformError( $params, $err );
 493                 }
 494
 495                 return false; # No error
 496         }
 497
 498         /**
 499          * Log an error that occurred in an external process
 500          *
 501          * @param $retval int
 502          * @param $err int
 503          * @param $cmd string
 504          */
 505         protected function logErrorForExternalProcess( $retval, $err, $cmd ) {
 506                 wfDebugLog( 'thumbnail',
 507                         sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 508                                 wfHostname(), $retval, trim( $err ), $cmd ) );
 509         }
 510
 511         /**
 512          * Get a MediaTransformError with error 'thumbnail_error'
 513          *
 514          * @param array $params Parameter array as passed to the transform* functions
 515          * @param string $errMsg Error message
 516          * @return MediaTransformError
 517          */
 518         public function getMediaTransformError( $params, $errMsg ) {
 519                 return new MediaTransformError( 'thumbnail_error', $params['clientWidth'],
 520                         $params['clientHeight'], $errMsg );
 521         }
 522
 523         /**
 524          * Transform an image using the built in GD library
 525          *
 526          * @param $image File File associated with this thumbnail
 527          * @param array $params Array with scaler params
 528          *
 529          * @return MediaTransformError Error object if error occurred, false (=no error) otherwise
 530          */
 531         protected function transformGd( $image, $params ) {
 532                 # Use PHP's builtin GD library functions.
 533                 #
 534                 # First find out what kind of file this is, and select the correct
 535                 # input routine for this.
 536
 537                 $typemap = array(
 538                         'image/gif' => array( 'imagecreatefromgif', 'palette', 'imagegif' ),
 539                         'image/jpeg' => array( 'imagecreatefromjpeg', 'truecolor',
 540                                 array( __CLASS__, 'imageJpegWrapper' ) ),
 541                         'image/png' => array( 'imagecreatefrompng', 'bits', 'imagepng' ),
 542                         'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette', 'imagewbmp' ),
 543                         'image/xbm' => array( 'imagecreatefromxbm', 'palette', 'imagexbm' ),
 544                 );
 545                 if ( !isset( $typemap[$params['mimeType']] ) ) {
 546                         $err = 'Image type not supported';
 547                         wfDebug( "$err\n" );
 548                         $errMsg = wfMessage( 'thumbnail_image-type' )->text();
 549
 550                         return $this->getMediaTransformError( $params, $errMsg );
 551                 }
 552                 list( $loader, $colorStyle, $saveType ) = $typemap[$params['mimeType']];
 553
 554                 if ( !function_exists( $loader ) ) {
 555                         $err = "Incomplete GD library configuration: missing function $loader";
 556                         wfDebug( "$err\n" );
 557                         $errMsg = wfMessage( 'thumbnail_gd-library', $loader )->text();
 558
 559                         return $this->getMediaTransformError( $params, $errMsg );
 560                 }
 561
 562                 if ( !file_exists( $params['srcPath'] ) ) {
 563                         $err = "File seems to be missing: {$params['srcPath']}";
 564                         wfDebug( "$err\n" );
 565                         $errMsg = wfMessage( 'thumbnail_image-missing', $params['srcPath'] )->text();
 566
 567                         return $this->getMediaTransformError( $params, $errMsg );
 568                 }
 569
 570                 $src_image = call_user_func( $loader, $params['srcPath'] );
 571
 572                 $rotation = function_exists( 'imagerotate' ) ? $this->getRotation( $image ) : 0;
 573                 list( $width, $height ) = $this->extractPreRotationDimensions( $params, $rotation );
 574                 $dst_image = imagecreatetruecolor( $width, $height );
 575
 576                 // Initialise the destination image to transparent instead of
 577                 // the default solid black, to support PNG and GIF transparency nicely
 578                 $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 579                 imagecolortransparent( $dst_image, $background );
 580                 imagealphablending( $dst_image, false );
 581
 582                 if ( $colorStyle == 'palette' ) {
 583                         // Don't resample for paletted GIF images.
 584                         // It may just uglify them, and completely breaks transparency.
 585                         imagecopyresized( $dst_image, $src_image,
 586                                 0, 0, 0, 0,
 587                                 $width, $height,
 588                                 imagesx( $src_image ), imagesy( $src_image ) );
 589                 } else {
 590                         imagecopyresampled( $dst_image, $src_image,
 591                                 0, 0, 0, 0,
 592                                 $width, $height,
 593                                 imagesx( $src_image ), imagesy( $src_image ) );
 594                 }
 595
 596                 if ( $rotation % 360 != 0 && $rotation % 90 == 0 ) {
 597                         $rot_image = imagerotate( $dst_image, $rotation, 0 );
 598                         imagedestroy( $dst_image );
 599                         $dst_image = $rot_image;
 600                 }
 601
 602                 imagesavealpha( $dst_image, true );
 603
 604                 call_user_func( $saveType, $dst_image, $params['dstPath'] );
 605                 imagedestroy( $dst_image );
 606                 imagedestroy( $src_image );
 607
 608                 return false; # No error
 609         }
 610
 611         /**
 612          * Escape a string for ImageMagick's property input (e.g. -set -comment)
 613          * See InterpretImageProperties() in magick/property.c
 614          * @return mixed|string
 615          */
 616         function escapeMagickProperty( $s ) {
 617                 // Double the backslashes
 618                 $s = str_replace( '\\', '\\\\', $s );
 619                 // Double the percents
 620                 $s = str_replace( '%', '%%', $s );
 621                 // Escape initial - or @
 622                 if ( strlen( $s ) > 0 && ( $s[0] === '-' || $s[0] === '@' ) ) {
 623                         $s = '\\' . $s;
 624                 }
 625
 626                 return $s;
 627         }
 628
 629         /**
 630          * Escape a string for ImageMagick's input filenames. See ExpandFilenames()
 631          * and GetPathComponent() in magick/utility.c.
 632          *
 633          * This won't work with an initial ~ or @, so input files should be prefixed
 634          * with the directory name.
 635          *
 636          * Glob character unescaping is broken in ImageMagick before 6.6.1-5, but
 637          * it's broken in a way that doesn't involve trying to convert every file
 638          * in a directory, so we're better off escaping and waiting for the bugfix
 639          * to filter down to users.
 640          *
 641          * @param string $path The file path
 642          * @param bool|string $scene The scene specification, or false if there is none
 643          * @throws MWException
 644          * @return string
 645          */
 646         function escapeMagickInput( $path, $scene = false ) {
 647                 # Die on initial metacharacters (caller should prepend path)
 648                 $firstChar = substr( $path, 0, 1 );
 649                 if ( $firstChar === '~' || $firstChar === '@' ) {
 650                         throw new MWException( __METHOD__ . ': cannot escape this path name' );
 651                 }
 652
 653                 # Escape glob chars
 654                 $path = preg_replace( '/[*?\[\]{}]/', '\\\\\0', $path );
 655
 656                 return $this->escapeMagickPath( $path, $scene );
 657         }
 658
 659         /**
 660          * Escape a string for ImageMagick's output filename. See
 661          * InterpretImageFilename() in magick/image.c.
 662          * @return string
 663          */
 664         function escapeMagickOutput( $path, $scene = false ) {
 665                 $path = str_replace( '%', '%%', $path );
 666
 667                 return $this->escapeMagickPath( $path, $scene );
 668         }
 669
 670         /**
 671          * Armour a string against ImageMagick's GetPathComponent(). This is a
 672          * helper function for escapeMagickInput() and escapeMagickOutput().
 673          *
 674          * @param string $path The file path
 675          * @param bool|string $scene The scene specification, or false if there is none
 676          * @throws MWException
 677          * @return string
 678          */
 679         protected function escapeMagickPath( $path, $scene = false ) {
 680                 # Die on format specifiers (other than drive letters). The regex is
 681                 # meant to match all the formats you get from "convert -list format"
 682                 if ( preg_match( '/^([a-zA-Z0-9-]+):/', $path, $m ) ) {
 683                         if ( wfIsWindows() && is_dir( $m[0] ) ) {
 684                                 // OK, it's a drive letter
 685                                 // ImageMagick has a similar exception, see IsMagickConflict()
 686                         } else {
 687                                 throw new MWException( __METHOD__ . ': unexpected colon character in path name' );
 688                         }
 689                 }
 690
 691                 # If there are square brackets, add a do-nothing scene specification
 692                 # to force a literal interpretation
 693                 if ( $scene === false ) {
 694                         if ( strpos( $path, '[' ) !== false ) {
 695                                 $path .= '[0--1]';
 696                         }
 697                 } else {
 698                         $path .= "[$scene]";
 699                 }
 700
 701                 return $path;
 702         }
 703
 704         /**
 705          * Retrieve the version of the installed ImageMagick
 706          * You can use PHPs version_compare() to use this value
 707          * Value is cached for one hour.
 708          * @return String representing the IM version.
 709          */
 710         protected function getMagickVersion() {
 711                 global $wgMemc;
 712
 713                 $cache = $wgMemc->get( "imagemagick-version" );
 714                 if ( !$cache ) {
 715                         global $wgImageMagickConvertCommand;
 716                         $cmd = wfEscapeShellArg( $wgImageMagickConvertCommand ) . ' -version';
 717                         wfDebug( __METHOD__ . ": Running convert -version\n" );
 718                         $retval = '';
 719                         $return = wfShellExec( $cmd, $retval );
 720                         $x = preg_match( '/Version: ImageMagick ([0-9]*\.[0-9]*\.[0-9]*)/', $return, $matches );
 721                         if ( $x != 1 ) {
 722                                 wfDebug( __METHOD__ . ": ImageMagick version check failed\n" );
 723
 724                                 return null;
 725                         }
 726                         $wgMemc->set( "imagemagick-version", $matches[1], 3600 );
 727
 728                         return $matches[1];
 729                 }
 730
 731                 return $cache;
 732         }
 733
 734         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 735                 imageinterlace( $dst_image );
 736                 imagejpeg( $dst_image, $thumbPath, 95 );
 737         }
 738
 739         /**
 740          * Returns whether the current scaler supports rotation (im and gd do)
 741          *
 742          * @return bool
 743          */
 744         public static function canRotate() {
 745                 $scaler = self::getScalerType( null, false );
 746                 switch ( $scaler ) {
 747                         case 'im':
 748                                 # ImageMagick supports autorotation
 749                                 return true;
 750                         case 'imext':
 751                                 # Imagick::rotateImage
 752                                 return true;
 753                         case 'gd':
 754                                 # GD's imagerotate function is used to rotate images, but not
 755                                 # all precompiled PHP versions have that function
 756                                 return function_exists( 'imagerotate' );
 757                         default:
 758                                 # Other scalers don't support rotation
 759                                 return false;
 760                 }
 761         }
 762
 763         /**
 764          * @param $file File
 765          * @param array $params Rotate parameters.
 766          *    'rotation' clockwise rotation in degrees, allowed are multiples of 90
 767          * @since 1.21
 768          * @return bool
 769          */
 770         public function rotate( $file, $params ) {
 771                 global $wgImageMagickConvertCommand;
 772
 773                 $rotation = ( $params['rotation'] + $this->getRotation( $file ) ) % 360;
 774                 $scene = false;
 775
 776                 $scaler = self::getScalerType( null, false );
 777                 switch ( $scaler ) {
 778                         case 'im':
 779                                 $cmd = wfEscapeShellArg( $wgImageMagickConvertCommand ) . " " .
 780                                         wfEscapeShellArg( $this->escapeMagickInput( $params['srcPath'], $scene ) ) .
 781                                         " -rotate -$rotation " .
 782                                         wfEscapeShellArg( $this->escapeMagickOutput( $params['dstPath'] ) );
 783                                 wfDebug( __METHOD__ . ": running ImageMagick: $cmd\n" );
 784                                 wfProfileIn( 'convert' );
 785                                 $retval = 0;
 786                                 $err = wfShellExecWithStderr( $cmd, $retval, $env );
 787                                 wfProfileOut( 'convert' );
 788                                 if ( $retval !== 0 ) {
 789                                         $this->logErrorForExternalProcess( $retval, $err, $cmd );
 790
 791                                         return new MediaTransformError( 'thumbnail_error', 0, 0, $err );
 792                                 }
 793
 794                                 return false;
 795                         case 'imext':
 796                                 $im = new Imagick();
 797                                 $im->readImage( $params['srcPath'] );
 798                                 if ( !$im->rotateImage( new ImagickPixel( 'white' ), 360 - $rotation ) ) {
 799                                         return new MediaTransformError( 'thumbnail_error', 0, 0,
 800                                                 "Error rotating $rotation degrees" );
 801                                 }
 802                                 $result = $im->writeImage( $params['dstPath'] );
 803                                 if ( !$result ) {
 804                                         return new MediaTransformError( 'thumbnail_error', 0, 0,
 805                                                 "Unable to write image to {$params['dstPath']}" );
 806                                 }
 807
 808                                 return false;
 809                         default:
 810                                 return new MediaTransformError( 'thumbnail_error', 0, 0,
 811                                         "$scaler rotation not implemented" );
 812                 }
 813         }
 814
 815         /**
 816          * Rerurns whether the file needs to be rendered. Returns true if the
 817          * file requires rotation and we are able to rotate it.
 818          *
 819          * @param $file File
 820          * @return bool
 821          */
 822         public function mustRender( $file ) {
 823                 return self::canRotate() && $this->getRotation( $file ) != 0;
 824         }
 825 }