includes/media/Bitmap.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup Media
   5  */
   6
   7 /**
   8  * @ingroup Media
   9  */
  10 class BitmapHandler extends ImageHandler {
  11         function normaliseParams( $image, &$params ) {
  12                 global $wgMaxImageArea;
  13                 if ( !parent::normaliseParams( $image, $params ) ) {
  14                         return false;
  15                 }
  16
  17                 $mimeType = $image->getMimeType();
  18                 $srcWidth = $image->getWidth( $params['page'] );
  19                 $srcHeight = $image->getHeight( $params['page'] );
  20
  21                 # Don't thumbnail an image so big that it will fill hard drives and send servers into swap
  22                 # JPEG has the handy property of allowing thumbnailing without full decompression, so we make
  23                 # an exception for it.
  24                 if ( $mimeType !== 'image/jpeg' &&
  25                         $srcWidth * $srcHeight > $wgMaxImageArea )
  26                 {
  27                         return false;
  28                 }
  29
  30                 # Don't make an image bigger than the source
  31                 $params['physicalWidth'] = $params['width'];
  32                 $params['physicalHeight'] = $params['height'];
  33
  34                 if ( $params['physicalWidth'] >= $srcWidth ) {
  35                         $params['physicalWidth'] = $srcWidth;
  36                         $params['physicalHeight'] = $srcHeight;
  37                         return true;
  38                 }
  39
  40                 return true;
  41         }
  42
  43         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
  44                 global $wgUseImageMagick, $wgImageMagickConvertCommand, $wgImageMagickTempDir;
  45                 global $wgCustomConvertCommand;
  46                 global $wgSharpenParameter, $wgSharpenReductionThreshold;
  47                 global $wgMaxAnimatedGifArea;
  48
  49                 if ( !$this->normaliseParams( $image, $params ) ) {
  50                         return new TransformParameterError( $params );
  51                 }
  52                 $physicalWidth = $params['physicalWidth'];
  53                 $physicalHeight = $params['physicalHeight'];
  54                 $clientWidth = $params['width'];
  55                 $clientHeight = $params['height'];
  56                 $srcWidth = $image->getWidth();
  57                 $srcHeight = $image->getHeight();
  58                 $mimeType = $image->getMimeType();
  59                 $srcPath = $image->getPath();
  60                 $retval = 0;
  61                 wfDebug( __METHOD__.": creating {$physicalWidth}x{$physicalHeight} thumbnail at $dstPath\n" );
  62
  63                 if ( !$image->mustRender() && $physicalWidth == $srcWidth && $physicalHeight == $srcHeight ) {
  64                         # normaliseParams (or the user) wants us to return the unscaled image
  65                         wfDebug( __METHOD__.": returning unscaled image\n" );
  66                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  67                 }
  68
  69                 if ( !$dstPath ) {
  70                         // No output path available, client side scaling only
  71                         $scaler = 'client';
  72                 } elseif ( $wgUseImageMagick ) {
  73                         $scaler = 'im';
  74                 } elseif ( $wgCustomConvertCommand ) {
  75                         $scaler = 'custom';
  76                 } elseif ( function_exists( 'imagecreatetruecolor' ) ) {
  77                         $scaler = 'gd';
  78                 } else {
  79                         $scaler = 'client';
  80                 }
  81                 wfDebug( __METHOD__.": scaler $scaler\n" );
  82
  83                 if ( $scaler == 'client' ) {
  84                         # Client-side image scaling, use the source URL
  85                         # Using the destination URL in a TRANSFORM_LATER request would be incorrect
  86                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  87                 }
  88
  89                 if ( $flags & self::TRANSFORM_LATER ) {
  90                         wfDebug( __METHOD__.": Transforming later per flags.\n" );
  91                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
  92                 }
  93
  94                 if ( !wfMkdirParents( dirname( $dstPath ) ) ) {
  95                         wfDebug( __METHOD__.": Unable to create thumbnail destination directory, falling back to client scaling\n" );
  96                         return new ThumbnailImage( $image, $image->getURL(), $clientWidth, $clientHeight, $srcPath );
  97                 }
  98
  99                 if ( $scaler == 'im' ) {
 100                         # use ImageMagick
 101
 102                         $quality = '';
 103                         $sharpen = '';
 104                         $frame = '';
 105                         $animation = '';
 106                         if ( $mimeType == 'image/jpeg' ) {
 107                                 $quality = "-quality 80"; // 80%
 108                                 # Sharpening, see bug 6193
 109                                 if ( ( $physicalWidth + $physicalHeight ) / ( $srcWidth + $srcHeight ) < $wgSharpenReductionThreshold ) {
 110                                         $sharpen = "-sharpen " . wfEscapeShellArg( $wgSharpenParameter );
 111                                 }
 112                         } elseif ( $mimeType == 'image/png' ) {
 113                                 $quality = "-quality 95"; // zlib 9, adaptive filtering
 114                         } elseif( $mimeType == 'image/gif' ) {
 115                                 if( $srcWidth * $srcHeight > $wgMaxAnimatedGifArea ) {
 116                                         // Extract initial frame only; we're so big it'll
 117                                         // be a total drag. :P
 118                                         $frame = '[0]';
 119                                 } else {
 120                                         // Coalesce is needed to scale animated GIFs properly (bug 1017).
 121                                         $animation = ' -coalesce ';
 122                                 }
 123                         }
 124
 125                         if ( strval( $wgImageMagickTempDir ) !== '' ) {
 126                                 $tempEnv = 'MAGICK_TMPDIR=' . wfEscapeShellArg( $wgImageMagickTempDir ) . ' ';
 127                         } else {
 128                                 $tempEnv = '';
 129                         }
 130
 131                         # Specify white background color, will be used for transparent images
 132                         # in Internet Explorer/Windows instead of default black.
 133
 134                         # Note, we specify "-size {$physicalWidth}" and NOT "-size {$physicalWidth}x{$physicalHeight}".
 135                         # It seems that ImageMagick has a bug wherein it produces thumbnails of
 136                         # the wrong size in the second case.
 137
 138                         $cmd  =
 139                                 $tempEnv .
 140                                 wfEscapeShellArg($wgImageMagickConvertCommand) .
 141                                 " {$quality} -background white -size {$physicalWidth} ".
 142                                 wfEscapeShellArg($srcPath . $frame) .
 143                                 $animation .
 144                                 // For the -resize option a "!" is needed to force exact size,
 145                                 // or ImageMagick may decide your ratio is wrong and slice off
 146                                 // a pixel.
 147                                 " -thumbnail " . wfEscapeShellArg( "{$physicalWidth}x{$physicalHeight}!" ) .
 148                                 " -depth 8 $sharpen " .
 149                                 wfEscapeShellArg($dstPath) . " 2>&1";
 150                         wfDebug( __METHOD__.": running ImageMagick: $cmd\n");
 151                         wfProfileIn( 'convert' );
 152                         $err = wfShellExec( $cmd, $retval );
 153                         wfProfileOut( 'convert' );
 154                 } elseif( $scaler == 'custom' ) {
 155                         # Use a custom convert command
 156                         # Variables: %s %d %w %h
 157                         $src = wfEscapeShellArg( $srcPath );
 158                         $dst = wfEscapeShellArg( $dstPath );
 159                         $cmd = $wgCustomConvertCommand;
 160                         $cmd = str_replace( '%s', $src, str_replace( '%d', $dst, $cmd ) ); # Filenames
 161                         $cmd = str_replace( '%h', $physicalHeight, str_replace( '%w', $physicalWidth, $cmd ) ); # Size
 162                         wfDebug( __METHOD__.": Running custom convert command $cmd\n" );
 163                         wfProfileIn( 'convert' );
 164                         $err = wfShellExec( $cmd, $retval );
 165                         wfProfileOut( 'convert' );
 166                 } else /* $scaler == 'gd' */ {
 167                         # Use PHP's builtin GD library functions.
 168                         #
 169                         # First find out what kind of file this is, and select the correct
 170                         # input routine for this.
 171
 172                         $typemap = array(
 173                                 'image/gif'          => array( 'imagecreatefromgif',  'palette',   'imagegif'  ),
 174                                 'image/jpeg'         => array( 'imagecreatefromjpeg', 'truecolor', array( __CLASS__, 'imageJpegWrapper' ) ),
 175                                 'image/png'          => array( 'imagecreatefrompng',  'bits',      'imagepng'  ),
 176                                 'image/vnd.wap.wbmp' => array( 'imagecreatefromwbmp', 'palette',   'imagewbmp'  ),
 177                                 'image/xbm'          => array( 'imagecreatefromxbm',  'palette',   'imagexbm'  ),
 178                         );
 179                         if( !isset( $typemap[$mimeType] ) ) {
 180                                 $err = 'Image type not supported';
 181                                 wfDebug( "$err\n" );
 182                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 183                         }
 184                         list( $loader, $colorStyle, $saveType ) = $typemap[$mimeType];
 185
 186                         if( !function_exists( $loader ) ) {
 187                                 $err = "Incomplete GD library configuration: missing function $loader";
 188                                 wfDebug( "$err\n" );
 189                                 return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 190                         }
 191
 192                         $src_image = call_user_func( $loader, $srcPath );
 193                         $dst_image = imagecreatetruecolor( $physicalWidth, $physicalHeight );
 194
 195                         // Initialise the destination image to transparent instead of
 196                         // the default solid black, to support PNG and GIF transparency nicely
 197                         $background = imagecolorallocate( $dst_image, 0, 0, 0 );
 198                         imagecolortransparent( $dst_image, $background );
 199                         imagealphablending( $dst_image, false );
 200
 201                         if( $colorStyle == 'palette' ) {
 202                                 // Don't resample for paletted GIF images.
 203                                 // It may just uglify them, and completely breaks transparency.
 204                                 imagecopyresized( $dst_image, $src_image,
 205                                         0,0,0,0,
 206                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 207                         } else {
 208                                 imagecopyresampled( $dst_image, $src_image,
 209                                         0,0,0,0,
 210                                         $physicalWidth, $physicalHeight, imagesx( $src_image ), imagesy( $src_image ) );
 211                         }
 212
 213                         imagesavealpha( $dst_image, true );
 214
 215                         call_user_func( $saveType, $dst_image, $dstPath );
 216                         imagedestroy( $dst_image );
 217                         imagedestroy( $src_image );
 218                         $retval = 0;
 219                 }
 220
 221                 $removed = $this->removeBadFile( $dstPath, $retval );
 222                 if ( $retval != 0 || $removed ) {
 223                         wfDebugLog( 'thumbnail',
 224                                 sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
 225                                         wfHostname(), $retval, trim($err), $cmd ) );
 226                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 227                 } else {
 228                         return new ThumbnailImage( $image, $dstUrl, $clientWidth, $clientHeight, $dstPath );
 229                 }
 230         }
 231
 232         static function imageJpegWrapper( $dst_image, $thumbPath ) {
 233                 imageinterlace( $dst_image );
 234                 imagejpeg( $dst_image, $thumbPath, 95 );
 235         }
 236
 237
 238         function getMetadata( $image, $filename ) {
 239                 global $wgShowEXIF;
 240                 if( $wgShowEXIF && file_exists( $filename ) ) {
 241                         $exif = new Exif( $filename );
 242                         $data = $exif->getFilteredData();
 243                         if ( $data ) {
 244                                 $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 245                                 return serialize( $data );
 246                         } else {
 247                                 return '0';
 248                         }
 249                 } else {
 250                         return '';
 251                 }
 252         }
 253
 254         function getMetadataType( $image ) {
 255                 return 'exif';
 256         }
 257
 258         function isMetadataValid( $image, $metadata ) {
 259                 global $wgShowEXIF;
 260                 if ( !$wgShowEXIF ) {
 261                         # Metadata disabled and so an empty field is expected
 262                         return true;
 263                 }
 264                 if ( $metadata === '0' ) {
 265                         # Special value indicating that there is no EXIF data in the file
 266                         return true;
 267                 }
 268                 $exif = @unserialize( $metadata );
 269                 if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
 270                         $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
 271                 {
 272                         # Wrong version
 273                         wfDebug( __METHOD__.": wrong version\n" );
 274                         return false;
 275                 }
 276                 return true;
 277         }
 278
 279         /**
 280          * Get a list of EXIF metadata items which should be displayed when
 281          * the metadata table is collapsed.
 282          *
 283          * @return array of strings
 284          * @access private
 285          */
 286         function visibleMetadataFields() {
 287                 $fields = array();
 288                 $lines = explode( "\n", wfMsgForContent( 'metadata-fields' ) );
 289                 foreach( $lines as $line ) {
 290                         $matches = array();
 291                         if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
 292                                 $fields[] = $matches[1];
 293                         }
 294                 }
 295                 $fields = array_map( 'strtolower', $fields );
 296                 return $fields;
 297         }
 298
 299         function formatMetadata( $image ) {
 300                 $result = array(
 301                         'visible' => array(),
 302                         'collapsed' => array()
 303                 );
 304                 $metadata = $image->getMetadata();
 305                 if ( !$metadata ) {
 306                         return false;
 307                 }
 308                 $exif = unserialize( $metadata );
 309                 if ( !$exif ) {
 310                         return false;
 311                 }
 312                 unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
 313                 $format = new FormatExif( $exif );
 314
 315                 $formatted = $format->getFormattedData();
 316                 // Sort fields into visible and collapsed
 317                 $visibleFields = $this->visibleMetadataFields();
 318                 foreach ( $formatted as $name => $value ) {
 319                         $tag = strtolower( $name );
 320                         self::addMeta( $result,
 321                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 322                                 'exif',
 323                                 $tag,
 324                                 $value
 325                         );
 326                 }
 327                 return $result;
 328         }
 329 }