diff options
Diffstat (limited to 'includes/media/DjVu.php')
-rw-r--r-- | includes/media/DjVu.php | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/includes/media/DjVu.php b/includes/media/DjVu.php new file mode 100644 index 00000000..3c053a0c --- /dev/null +++ b/includes/media/DjVu.php @@ -0,0 +1,206 @@ +<?php + +/** + * @addtogroup Media + */ +class DjVuHandler extends ImageHandler { + function isEnabled() { + global $wgDjvuRenderer, $wgDjvuDump, $wgDjvuToXML; + if ( !$wgDjvuRenderer || ( !$wgDjvuDump && !$wgDjvuToXML ) ) { + wfDebug( "DjVu is disabled, please set \$wgDjvuRenderer and \$wgDjvuDump\n" ); + return false; + } else { + return true; + } + } + + function mustRender() { return true; } + function isMultiPage() { return true; } + + function validateParam( $name, $value ) { + if ( in_array( $name, array( 'width', 'height', 'page' ) ) ) { + if ( $value <= 0 ) { + return false; + } else { + return true; + } + } else { + return false; + } + } + + function makeParamString( $params ) { + $page = isset( $params['page'] ) ? $params['page'] : 1; + if ( !isset( $params['width'] ) ) { + return false; + } + return "page{$page}-{$params['width']}px"; + } + + function parseParamString( $str ) { + $m = false; + if ( preg_match( '/^page(\d+)-(\d+)px$/', $str, $m ) ) { + return array( 'width' => $m[2], 'page' => $m[1] ); + } else { + return false; + } + } + + function getScriptParams( $params ) { + return array( + 'width' => $params['width'], + 'page' => $params['page'], + ); + } + + function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) { + global $wgDjvuRenderer, $wgDjvuPostProcessor; + + // Fetch XML and check it, to give a more informative error message than the one which + // normaliseParams will inevitably give. + $xml = $image->getMetadata(); + if ( !$xml ) { + return new MediaTransformError( 'thumbnail_error', @$params['width'], @$params['height'], + wfMsg( 'djvu_no_xml' ) ); + } + + if ( !$this->normaliseParams( $image, $params ) ) { + return new TransformParameterError( $params ); + } + $width = $params['width']; + $height = $params['height']; + $srcPath = $image->getImagePath(); + $page = $params['page']; + $pageCount = $this->pageCount( $image ); + if ( $page > $this->pageCount( $image ) ) { + return new MediaTransformError( 'thumbnail_error', $width, $height, wfMsg( 'djvu_page_error' ) ); + } + + if ( $flags & self::TRANSFORM_LATER ) { + return new ThumbnailImage( $dstUrl, $width, $height, $dstPath ); + } + + if ( !wfMkdirParents( dirname( $dstPath ) ) ) { + return new MediaTransformError( 'thumbnail_error', $width, $height, wfMsg( 'thumbnail_dest_directory' ) ); + } + + # Use a subshell (brackets) to aggregate stderr from both pipeline commands + # before redirecting it to the overall stdout. This works in both Linux and Windows XP. + $cmd = '(' . wfEscapeShellArg( $wgDjvuRenderer ) . " -format=ppm -page={$page} -size={$width}x{$height} " . + wfEscapeShellArg( $srcPath ); + if ( $wgDjvuPostProcessor ) { + $cmd .= " | {$wgDjvuPostProcessor}"; + } + $cmd .= ' > ' . wfEscapeShellArg($dstPath) . ') 2>&1'; + wfProfileIn( 'ddjvu' ); + wfDebug( __METHOD__.": $cmd\n" ); + $err = wfShellExec( $cmd, $retval ); + wfProfileOut( 'ddjvu' ); + + $removed = $this->removeBadFile( $dstPath, $retval ); + if ( $retval != 0 || $removed ) { + wfDebugLog( 'thumbnail', + sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"', + wfHostname(), $retval, trim($err), $cmd ) ); + return new MediaTransformError( 'thumbnail_error', $width, $height, $err ); + } else { + return new ThumbnailImage( $dstUrl, $width, $height, $dstPath ); + } + } + + /** + * Cache an instance of DjVuImage in an Image object, return that instance + */ + function getDjVuImage( $image, $path ) { + if ( !$image ) { + $deja = new DjVuImage( $path ); + } elseif ( !isset( $image->dejaImage ) ) { + $deja = $image->dejaImage = new DjVuImage( $path ); + } else { + $deja = $image->dejaImage; + } + return $deja; + } + + /** + * Cache a document tree for the DjVu XML metadata + */ + function getMetaTree( $image ) { + if ( isset( $image->dejaMetaTree ) ) { + return $image->dejaMetaTree; + } + + $metadata = $image->getMetadata(); + if ( !$this->isMetadataValid( $image, $metadata ) ) { + wfDebug( "DjVu XML metadata is invalid or missing, should have been fixed in upgradeRow\n" ); + return false; + } + wfProfileIn( __METHOD__ ); + + wfSuppressWarnings(); + try { + $image->dejaMetaTree = new SimpleXMLElement( $metadata ); + } catch( Exception $e ) { + wfDebug( "Bogus multipage XML metadata on '$image->name'\n" ); + // Set to false rather than null to avoid further attempts + $image->dejaMetaTree = false; + } + wfRestoreWarnings(); + wfProfileOut( __METHOD__ ); + return $image->dejaMetaTree; + } + + function getImageSize( $image, $path ) { + return $this->getDjVuImage( $image, $path )->getImageSize(); + } + + function getThumbType( $ext, $mime ) { + global $wgDjvuOutputExtension; + static $mime; + if ( !isset( $mime ) ) { + $magic = MimeMagic::singleton(); + $mime = $magic->guessTypesForExtension( $wgDjvuOutputExtension ); + } + return array( $wgDjvuOutputExtension, $mime ); + } + + function getMetadata( $image, $path ) { + wfDebug( "Getting DjVu metadata for $path\n" ); + return $this->getDjVuImage( $image, $path )->retrieveMetaData(); + } + + function getMetadataType( $image ) { + return 'djvuxml'; + } + + function isMetadataValid( $image, $metadata ) { + return !empty( $metadata ) && $metadata != serialize(array()); + } + + function pageCount( $image ) { + $tree = $this->getMetaTree( $image ); + if ( !$tree ) { + return false; + } + return count( $tree->xpath( '//OBJECT' ) ); + } + + function getPageDimensions( $image, $page ) { + $tree = $this->getMetaTree( $image ); + if ( !$tree ) { + return false; + } + + $o = $tree->BODY[0]->OBJECT[$page-1]; + if ( $o ) { + return array( + 'width' => intval( $o['width'] ), + 'height' => intval( $o['height'] ) + ); + } else { + return false; + } + } +} + +?> |