includes/media/ImageHandler.php

   1 <?php
   2 /**
   3  * Media-handling base classes and generic functionality.
   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  * Media handler abstract base class for images
  26  *
  27  * @ingroup Media
  28  */
  29 abstract class ImageHandler extends MediaHandler {
  30         /**
  31          * @param File $file
  32          * @return bool
  33          */
  34         function canRender( $file ) {
  35                 return ( $file->getWidth() && $file->getHeight() );
  36         }
  37
  38         function getParamMap() {
  39                 return array( 'img_width' => 'width' );
  40         }
  41
  42         function validateParam( $name, $value ) {
  43                 if ( in_array( $name, array( 'width', 'height' ) ) ) {
  44                         if ( $value <= 0 ) {
  45                                 return false;
  46                         } else {
  47                                 return true;
  48                         }
  49                 } else {
  50                         return false;
  51                 }
  52         }
  53
  54         function makeParamString( $params ) {
  55                 if ( isset( $params['physicalWidth'] ) ) {
  56                         $width = $params['physicalWidth'];
  57                 } elseif ( isset( $params['width'] ) ) {
  58                         $width = $params['width'];
  59                 } else {
  60                         throw new MWException( 'No width specified to ' . __METHOD__ );
  61                 }
  62
  63                 # Removed for ProofreadPage
  64                 #$width = intval( $width );
  65                 return "{$width}px";
  66         }
  67
  68         function parseParamString( $str ) {
  69                 $m = false;
  70                 if ( preg_match( '/^(\d+)px$/', $str, $m ) ) {
  71                         return array( 'width' => $m[1] );
  72                 } else {
  73                         return false;
  74                 }
  75         }
  76
  77         function getScriptParams( $params ) {
  78                 return array( 'width' => $params['width'] );
  79         }
  80
  81         /**
  82          * @param File $image
  83          * @param array $params
  84          * @return bool
  85          */
  86         function normaliseParams( $image, &$params ) {
  87                 $mimeType = $image->getMimeType();
  88
  89                 if ( !isset( $params['width'] ) ) {
  90                         return false;
  91                 }
  92
  93                 if ( !isset( $params['page'] ) ) {
  94                         $params['page'] = 1;
  95                 } else {
  96                         $params['page'] = intval( $params['page'] );
  97                         if ( $params['page'] > $image->pageCount() ) {
  98                                 $params['page'] = $image->pageCount();
  99                         }
 100
 101                         if ( $params['page'] < 1 ) {
 102                                 $params['page'] = 1;
 103                         }
 104                 }
 105
 106                 $srcWidth = $image->getWidth( $params['page'] );
 107                 $srcHeight = $image->getHeight( $params['page'] );
 108
 109                 if ( isset( $params['height'] ) && $params['height'] != -1 ) {
 110                         # Height & width were both set
 111                         if ( $params['width'] * $srcHeight > $params['height'] * $srcWidth ) {
 112                                 # Height is the relative smaller dimension, so scale width accordingly
 113                                 $params['width'] = self::fitBoxWidth( $srcWidth, $srcHeight, $params['height'] );
 114
 115                                 if ( $params['width'] == 0 ) {
 116                                         # Very small image, so we need to rely on client side scaling :(
 117                                         $params['width'] = 1;
 118                                 }
 119
 120                                 $params['physicalWidth'] = $params['width'];
 121                         } else {
 122                                 # Height was crap, unset it so that it will be calculated later
 123                                 unset( $params['height'] );
 124                         }
 125                 }
 126
 127                 if ( !isset( $params['physicalWidth'] ) ) {
 128                         # Passed all validations, so set the physicalWidth
 129                         $params['physicalWidth'] = $params['width'];
 130                 }
 131
 132                 # Because thumbs are only referred to by width, the height always needs
 133                 # to be scaled by the width to keep the thumbnail sizes consistent,
 134                 # even if it was set inside the if block above
 135                 $params['physicalHeight'] = File::scaleHeight( $srcWidth, $srcHeight,
 136                         $params['physicalWidth'] );
 137
 138                 # Set the height if it was not validated in the if block higher up
 139                 if ( !isset( $params['height'] ) || $params['height'] == -1 ) {
 140                         $params['height'] = $params['physicalHeight'];
 141                 }
 142
 143                 if ( !$this->validateThumbParams( $params['physicalWidth'],
 144                         $params['physicalHeight'], $srcWidth, $srcHeight, $mimeType )
 145                 ) {
 146                         return false;
 147                 }
 148
 149                 return true;
 150         }
 151
 152         /**
 153          * Validate thumbnail parameters and fill in the correct height
 154          *
 155          * @param int $width Specified width (input/output)
 156          * @param int $height Height (output only)
 157          * @param int $srcWidth Width of the source image
 158          * @param int $srcHeight Height of the source image
 159          * @param string $mimeType Unused
 160          * @return bool False to indicate that an error should be returned to the user.
 161          */
 162         function validateThumbParams( &$width, &$height, $srcWidth, $srcHeight, $mimeType ) {
 163                 $width = intval( $width );
 164
 165                 # Sanity check $width
 166                 if ( $width <= 0 ) {
 167                         wfDebug( __METHOD__ . ": Invalid destination width: $width\n" );
 168
 169                         return false;
 170                 }
 171                 if ( $srcWidth <= 0 ) {
 172                         wfDebug( __METHOD__ . ": Invalid source width: $srcWidth\n" );
 173
 174                         return false;
 175                 }
 176
 177                 $height = File::scaleHeight( $srcWidth, $srcHeight, $width );
 178                 if ( $height == 0 ) {
 179                         # Force height to be at least 1 pixel
 180                         $height = 1;
 181                 }
 182
 183                 return true;
 184         }
 185
 186         /**
 187          * @param File $image
 188          * @param string $script
 189          * @param array $params
 190          * @return bool|MediaTransformOutput
 191          */
 192         function getScriptedTransform( $image, $script, $params ) {
 193                 if ( !$this->normaliseParams( $image, $params ) ) {
 194                         return false;
 195                 }
 196                 $url = wfAppendQuery( $script, $this->getScriptParams( $params ) );
 197
 198                 if ( $image->mustRender() || $params['width'] < $image->getWidth() ) {
 199                         return new ThumbnailImage( $image, $url, false, $params );
 200                 }
 201         }
 202
 203         function getImageSize( $image, $path ) {
 204                 wfSuppressWarnings();
 205                 $gis = getimagesize( $path );
 206                 wfRestoreWarnings();
 207
 208                 return $gis;
 209         }
 210
 211         /**
 212          * Function that returns the number of pixels to be thumbnailed.
 213          * Intended for animated GIFs to multiply by the number of frames.
 214          *
 215          * If the file doesn't support a notion of "area" return 0.
 216          *
 217          * @param File $image
 218          * @return int
 219          */
 220         function getImageArea( $image ) {
 221                 return $image->getWidth() * $image->getHeight();
 222         }
 223
 224         /**
 225          * @param File $file
 226          * @return string
 227          */
 228         function getShortDesc( $file ) {
 229                 global $wgLang;
 230                 $nbytes = htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
 231                 $widthheight = wfMessage( 'widthheight' )
 232                         ->numParams( $file->getWidth(), $file->getHeight() )->escaped();
 233
 234                 return "$widthheight ($nbytes)";
 235         }
 236
 237         /**
 238          * @param File $file
 239          * @return string
 240          */
 241         function getLongDesc( $file ) {
 242                 global $wgLang;
 243                 $pages = $file->pageCount();
 244                 $size = htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
 245                 if ( $pages === false || $pages <= 1 ) {
 246                         $msg = wfMessage( 'file-info-size' )->numParams( $file->getWidth(),
 247                                 $file->getHeight() )->params( $size,
 248                                         $file->getMimeType() )->parse();
 249                 } else {
 250                         $msg = wfMessage( 'file-info-size-pages' )->numParams( $file->getWidth(),
 251                                 $file->getHeight() )->params( $size,
 252                                         $file->getMimeType() )->numParams( $pages )->parse();
 253                 }
 254
 255                 return $msg;
 256         }
 257
 258         /**
 259          * @param File $file
 260          * @return string
 261          */
 262         function getDimensionsString( $file ) {
 263                 $pages = $file->pageCount();
 264                 if ( $pages > 1 ) {
 265                         return wfMessage( 'widthheightpage' )
 266                                 ->numParams( $file->getWidth(), $file->getHeight(), $pages )->text();
 267                 } else {
 268                         return wfMessage( 'widthheight' )
 269                                 ->numParams( $file->getWidth(), $file->getHeight() )->text();
 270                 }
 271         }
 272
 273         public function sanitizeParamsForBucketing( $params ) {
 274                 $params = parent::sanitizeParamsForBucketing( $params );
 275
 276                 // We unset the height parameters in order to let normaliseParams recalculate them
 277                 // Otherwise there might be a height discrepancy
 278                 if ( isset( $params['height'] ) ) {
 279                         unset( $params['height'] );
 280                 }
 281
 282                 if ( isset( $params['physicalHeight'] ) ) {
 283                         unset( $params['physicalHeight'] );
 284                 }
 285
 286                 return $params;
 287         }
 288 }