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