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