includes/media/Jpeg.php

   1 <?php
   2 /**
   3  * Handler for JPEG 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  * JPEG specific handler.
  26  * Inherits most stuff from BitmapHandler, just here to do the metadata handler differently.
  27  *
  28  * Metadata stuff common to Jpeg and built-in Tiff (not PagedTiffHandler) is
  29  * in ExifBitmapHandler.
  30  *
  31  * @ingroup Media
  32  */
  33 class JpegHandler extends ExifBitmapHandler {
  34
  35         function normaliseParams( $image, &$params ) {
  36                 if ( !parent::normaliseParams( $image, $params ) ) {
  37                         return false;
  38                 }
  39                 if ( isset( $params['quality'] ) && !self::validateQuality( $params['quality'] ) ) {
  40                         return false;
  41                 }
  42                 return true;
  43         }
  44
  45         public function validateParam( $name, $value ) {
  46                 if ( $name === 'quality' ) {
  47                         return self::validateQuality( $value );
  48                 } else {
  49                         return parent::validateParam( $name, $value );
  50                 }
  51         }
  52
  53         /** Validate and normalize quality value to be between 1 and 100 (inclusive).
  54          * @param int $value Quality value, will be converted to integer or 0 if invalid
  55          * @return bool True if the value is valid
  56          */
  57         private static function validateQuality( $value ) {
  58                 return $value === 'low';
  59         }
  60
  61         public function makeParamString( $params ) {
  62                 // Prepend quality as "qValue-". This has to match parseParamString() below
  63                 $res = parent::makeParamString( $params );
  64                 if ( $res && isset( $params['quality'] ) ) {
  65                         $res = "q{$params['quality']}-$res";
  66                 }
  67                 return $res;
  68         }
  69
  70         public function parseParamString( $str ) {
  71                 // $str contains "qlow-200px" or "200px" strings because thumb.php would strip the filename
  72                 // first - check if the string begins with "qlow-", and if so, treat it as quality.
  73                 // Pass the first portion, or the whole string if "qlow-" not found, to the parent
  74                 // The parsing must match the makeParamString() above
  75                 $res = false;
  76                 $m = false;
  77                 if ( preg_match( '/q([^-]+)-(.*)$/', $str, $m ) ) {
  78                         $v = $m[1];
  79                         if ( self::validateQuality( $v ) ) {
  80                                 $res = parent::parseParamString( $m[2] );
  81                                 if ( $res ) {
  82                                         $res['quality'] = $v;
  83                                 }
  84                         }
  85                 } else {
  86                         $res = parent::parseParamString( $str );
  87                 }
  88                 return $res;
  89         }
  90
  91         function getScriptParams( $params ) {
  92                 $res = parent::getScriptParams( $params );
  93                 if ( isset( $params['quality'] ) ) {
  94                         $res['quality'] = $params['quality'];
  95                 }
  96                 return $res;
  97         }
  98
  99         function getMetadata( $image, $filename ) {
 100                 try {
 101                         $meta = BitmapMetadataHandler::Jpeg( $filename );
 102                         if ( !is_array( $meta ) ) {
 103                                 // This should never happen, but doesn't hurt to be paranoid.
 104                                 throw new MWException( 'Metadata array is not an array' );
 105                         }
 106                         $meta['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
 107
 108                         return serialize( $meta );
 109                 } catch ( Exception $e ) {
 110                         // BitmapMetadataHandler throws an exception in certain exceptional
 111                         // cases like if file does not exist.
 112                         wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
 113
 114                         /* This used to use 0 (ExifBitmapHandler::OLD_BROKEN_FILE) for the cases
 115                          *   * No metadata in the file
 116                          *   * Something is broken in the file.
 117                          * However, if the metadata support gets expanded then you can't tell if the 0 is from
 118                          * a broken file, or just no props found. A broken file is likely to stay broken, but
 119                          * a file which had no props could have props once the metadata support is improved.
 120                          * Thus switch to using -1 to denote only a broken file, and use an array with only
 121                          * MEDIAWIKI_EXIF_VERSION to denote no props.
 122                          */
 123
 124                         return ExifBitmapHandler::BROKEN_FILE;
 125                 }
 126         }
 127
 128         /**
 129          * @param File $file
 130          * @param array $params Rotate parameters.
 131          *    'rotation' clockwise rotation in degrees, allowed are multiples of 90
 132          * @since 1.21
 133          * @return bool|MediaTransformError
 134          */
 135         public function rotate( $file, $params ) {
 136                 global $wgJpegTran;
 137
 138                 $rotation = ( $params['rotation'] + $this->getRotation( $file ) ) % 360;
 139
 140                 if ( $wgJpegTran && is_executable( $wgJpegTran ) ) {
 141                         $cmd = wfEscapeShellArg( $wgJpegTran ) .
 142                                 " -rotate " . wfEscapeShellArg( $rotation ) .
 143                                 " -outfile " . wfEscapeShellArg( $params['dstPath'] ) .
 144                                 " " . wfEscapeShellArg( $params['srcPath'] );
 145                         wfDebug( __METHOD__ . ": running jpgtran: $cmd\n" );
 146                         $retval = 0;
 147                         $err = wfShellExecWithStderr( $cmd, $retval );
 148                         if ( $retval !== 0 ) {
 149                                 $this->logErrorForExternalProcess( $retval, $err, $cmd );
 150
 151                                 return new MediaTransformError( 'thumbnail_error', 0, 0, $err );
 152                         }
 153
 154                         return false;
 155                 } else {
 156                         return parent::rotate( $file, $params );
 157                 }
 158         }
 159
 160         public function supportsBucketing() {
 161                 return true;
 162         }
 163
 164         public function sanitizeParamsForBucketing( $params ) {
 165                 $params = parent::sanitizeParamsForBucketing( $params );
 166
 167                 // Quality needs to be cleared for bucketing. Buckets need to be default quality
 168                 if ( isset( $params['quality'] ) ) {
 169                         unset( $params['quality'] );
 170                 }
 171
 172                 return $params;
 173         }
 174 }