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         /**
  32          * @param $file File
  33          * @return bool
  34          */
  35         function canRender( $file ) {
  36                 return ( $file->getWidth() && $file->getHeight() );
  37         }
  38
  39         function getParamMap() {
  40                 return array( 'img_width' => 'width' );
  41         }
  42
  43         function validateParam( $name, $value ) {
  44                 if ( in_array( $name, array( 'width', 'height' ) ) ) {
  45                         if ( $value <= 0 ) {
  46                                 return false;
  47                         } else {
  48                                 return true;
  49                         }
  50                 } else {
  51                         return false;
  52                 }
  53         }
  54
  55         function makeParamString( $params ) {
  56                 if ( isset( $params['physicalWidth'] ) ) {
  57                         $width = $params['physicalWidth'];
  58                 } elseif ( isset( $params['width'] ) ) {
  59                         $width = $params['width'];
  60                 } else {
  61                         throw new MWException( 'No width specified to ' . __METHOD__ );
  62                 }
  63                 # Removed for ProofreadPage
  64                 #$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 $image File
  83          * @param  $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                         if ( $params['page'] > $image->pageCount() ) {
  97                                 $params['page'] = $image->pageCount();
  98                         }
  99
 100                         if ( $params['page'] < 1 ) {
 101                                 $params['page'] = 1;
 102                         }
 103                 }
 104
 105                 $srcWidth = $image->getWidth( $params['page'] );
 106                 $srcHeight = $image->getHeight( $params['page'] );
 107
 108                 if ( isset( $params['height'] ) && $params['height'] != -1 ) {
 109                         # Height & width were both set
 110                         if ( $params['width'] * $srcHeight > $params['height'] * $srcWidth ) {
 111                                 # Height is the relative smaller dimension, so scale width accordingly
 112                                 $params['width'] = self::fitBoxWidth( $srcWidth, $srcHeight, $params['height'] );
 113
 114                                 if ( $params['width'] == 0 ) {
 115                                         # Very small image, so we need to rely on client side scaling :(
 116                                         $params['width'] = 1;
 117                                 }
 118
 119                                 $params['physicalWidth'] = $params['width'];
 120                         } else {
 121                                 # Height was crap, unset it so that it will be calculated later
 122                                 unset( $params['height'] );
 123                         }
 124                 }
 125
 126                 if ( !isset( $params['physicalWidth'] ) ) {
 127                         # Passed all validations, so set the physicalWidth
 128                         $params['physicalWidth'] = $params['width'];
 129                 }
 130
 131                 # Because thumbs are only referred to by width, the height always needs
 132                 # to be scaled by the width to keep the thumbnail sizes consistent,
 133                 # even if it was set inside the if block above
 134                 $params['physicalHeight'] = File::scaleHeight( $srcWidth, $srcHeight,
 135                         $params['physicalWidth'] );
 136
 137                 # Set the height if it was not validated in the if block higher up
 138                 if ( !isset( $params['height'] ) || $params['height'] == -1 ) {
 139                         $params['height'] = $params['physicalHeight'];
 140                 }
 141
 142                 if ( !$this->validateThumbParams( $params['physicalWidth'],
 143                                 $params['physicalHeight'], $srcWidth, $srcHeight, $mimeType ) ) {
 144                         return false;
 145                 }
 146                 return true;
 147         }
 148
 149         /**
 150          * Validate thumbnail parameters and fill in the correct height
 151          *
 152          * @param $width Integer: specified width (input/output)
 153          * @param $height Integer: height (output only)
 154          * @param $srcWidth Integer: width of the source image
 155          * @param $srcHeight Integer: height of the source image
 156          * @param $mimeType
 157          * @return bool False to indicate that an error should be returned to the user.
 158          */
 159         function validateThumbParams( &$width, &$height, $srcWidth, $srcHeight, $mimeType ) {
 160                 $width = intval( $width );
 161
 162                 # Sanity check $width
 163                 if ( $width <= 0 ) {
 164                         wfDebug( __METHOD__ . ": Invalid destination width: $width\n" );
 165                         return false;
 166                 }
 167                 if ( $srcWidth <= 0 ) {
 168                         wfDebug( __METHOD__ . ": Invalid source width: $srcWidth\n" );
 169                         return false;
 170                 }
 171
 172                 $height = File::scaleHeight( $srcWidth, $srcHeight, $width );
 173                 if ( $height == 0 ) {
 174                         # Force height to be at least 1 pixel
 175                         $height = 1;
 176                 }
 177                 return true;
 178         }
 179
 180         /**
 181          * @param $image File
 182          * @param  $script
 183          * @param  $params
 184          * @return bool|ThumbnailImage
 185          */
 186         function getScriptedTransform( $image, $script, $params ) {
 187                 if ( !$this->normaliseParams( $image, $params ) ) {
 188                         return false;
 189                 }
 190                 $url = wfAppendQuery( $script, $this->getScriptParams( $params ) );
 191
 192                 if ( $image->mustRender() || $params['width'] < $image->getWidth() ) {
 193                         return new ThumbnailImage( $image, $url, false, $params );
 194                 }
 195         }
 196
 197         function getImageSize( $image, $path ) {
 198                 wfSuppressWarnings();
 199                 $gis = getimagesize( $path );
 200                 wfRestoreWarnings();
 201                 return $gis;
 202         }
 203         /**
 204          * Function that returns the number of pixels to be thumbnailed.
 205          * Intended for animated GIFs to multiply by the number of frames.
 206          *
 207          * If the file doesn't support a notion of "area" return 0.
 208          *
 209          * @param File $image
 210          * @return int
 211          */
 212         function getImageArea( $image ) {
 213                 return $image->getWidth() * $image->getHeight();
 214         }
 215
 216         /**
 217          * @param $file File
 218          * @return string
 219          */
 220         function getShortDesc( $file ) {
 221                 global $wgLang;
 222                 $nbytes = htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
 223                 $widthheight = wfMessage( 'widthheight' )->numParams( $file->getWidth(), $file->getHeight() )->escaped();
 224
 225                 return "$widthheight ($nbytes)";
 226         }
 227
 228         /**
 229          * @param $file File
 230          * @return string
 231          */
 232         function getLongDesc( $file ) {
 233                 global $wgLang;
 234                 $pages = $file->pageCount();
 235                 $size = htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
 236                 if ( $pages === false || $pages <= 1 ) {
 237                         $msg = wfMessage( 'file-info-size' )->numParams( $file->getWidth(),
 238                                 $file->getHeight() )->params( $size,
 239                                 $file->getMimeType() )->parse();
 240                 } else {
 241                         $msg = wfMessage( 'file-info-size-pages' )->numParams( $file->getWidth(),
 242                                 $file->getHeight() )->params( $size,
 243                                 $file->getMimeType() )->numParams( $pages )->parse();
 244                 }
 245                 return $msg;
 246         }
 247
 248         /**
 249          * @param $file File
 250          * @return string
 251          */
 252         function getDimensionsString( $file ) {
 253                 $pages = $file->pageCount();
 254                 if ( $pages > 1 ) {
 255                         return wfMessage( 'widthheightpage' )->numParams( $file->getWidth(), $file->getHeight(), $pages )->text();
 256                 } else {
 257                         return wfMessage( 'widthheight' )->numParams( $file->getWidth(), $file->getHeight() )->text();
 258                 }
 259         }
 260 }