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