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Diffstat (limited to 'www/wiki/includes/media/XCF.php')
| -rw-r--r-- | www/wiki/includes/media/XCF.php | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/www/wiki/includes/media/XCF.php b/www/wiki/includes/media/XCF.php new file mode 100644 index 00000000..491fef21 --- /dev/null +++ b/www/wiki/includes/media/XCF.php @@ -0,0 +1,228 @@ +<?php +/** + * Handler for the Gimp's native file format (XCF) + * + * Overview: + * https://en.wikipedia.org/wiki/XCF_(file_format) + * Specification in Gnome repository: + * http://svn.gnome.org/viewvc/gimp/trunk/devel-docs/xcf.txt?view=markup + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + * @ingroup Media + */ + +/** + * Handler for the Gimp's native file format; getimagesize() doesn't + * support these files + * + * @ingroup Media + */ +class XCFHandler extends BitmapHandler { + /** + * @param File $file + * @return bool + */ + public function mustRender( $file ) { + return true; + } + + /** + * Render files as PNG + * + * @param string $ext + * @param string $mime + * @param array $params + * @return array + */ + function getThumbType( $ext, $mime, $params = null ) { + return [ 'png', 'image/png' ]; + } + + /** + * Get width and height from the XCF header. + * + * @param File|FSFile $image + * @param string $filename + * @return array + */ + function getImageSize( $image, $filename ) { + $header = self::getXCFMetaData( $filename ); + if ( !$header ) { + return false; + } + + # Forge a return array containing metadata information just like getimagesize() + # See PHP documentation at: https://secure.php.net/getimagesize + return [ + 0 => $header['width'], + 1 => $header['height'], + 2 => null, # IMAGETYPE constant, none exist for XCF. + 3 => "height=\"{$header['height']}\" width=\"{$header['width']}\"", + 'mime' => 'image/x-xcf', + 'channels' => null, + 'bits' => 8, # Always 8-bits per color + ]; + } + + /** + * Metadata for a given XCF file + * + * Will return false if file magic signature is not recognized + * @author Hexmode + * @author Hashar + * + * @param string $filename Full path to a XCF file + * @return bool|array Metadata Array just like PHP getimagesize() + */ + static function getXCFMetaData( $filename ) { + # Decode master structure + $f = fopen( $filename, 'rb' ); + if ( !$f ) { + return false; + } + # The image structure always starts at offset 0 in the XCF file. + # So we just read it :-) + $binaryHeader = fread( $f, 26 ); + fclose( $f ); + + /** + * Master image structure: + * + * byte[9] "gimp xcf " File type magic + * byte[4] version XCF version + * "file" - version 0 + * "v001" - version 1 + * "v002" - version 2 + * byte 0 Zero-terminator for version tag + * uint32 width With of canvas + * uint32 height Height of canvas + * uint32 base_type Color mode of the image; one of + * 0: RGB color + * 1: Grayscale + * 2: Indexed color + * (enum GimpImageBaseType in libgimpbase/gimpbaseenums.h) + */ + try { + $header = wfUnpack( + "A9magic" . # A: space padded + "/a5version" . # a: zero padded + "/Nwidth" . # \ + "/Nheight" . # N: unsigned long 32bit big endian + "/Nbase_type", # / + $binaryHeader + ); + } catch ( Exception $mwe ) { + return false; + } + + # Check values + if ( $header['magic'] !== 'gimp xcf' ) { + wfDebug( __METHOD__ . " '$filename' has invalid magic signature.\n" ); + + return false; + } + # TODO: we might want to check for sane values of width and height + + wfDebug( __METHOD__ . + ": canvas size of '$filename' is {$header['width']} x {$header['height']} px\n" ); + + return $header; + } + + /** + * Store the channel type + * + * Greyscale files need different command line options. + * + * @param File|FSFile $file The image object, or false if there isn't one. + * Warning, FSFile::getPropsFromPath might pass an (object)array() instead (!) + * @param string $filename + * @return string + */ + public function getMetadata( $file, $filename ) { + $header = self::getXCFMetaData( $filename ); + $metadata = []; + if ( $header ) { + // Try to be consistent with the names used by PNG files. + // Unclear from base media type if it has an alpha layer, + // so just assume that it does since it "potentially" could. + switch ( $header['base_type'] ) { + case 0: + $metadata['colorType'] = 'truecolour-alpha'; + break; + case 1: + $metadata['colorType'] = 'greyscale-alpha'; + break; + case 2: + $metadata['colorType'] = 'index-coloured'; + break; + default: + $metadata['colorType'] = 'unknown'; + } + } else { + // Marker to prevent repeated attempted extraction + $metadata['error'] = true; + } + return serialize( $metadata ); + } + + /** + * Should we refresh the metadata + * + * @param File $file The file object for the file in question + * @param string $metadata Serialized metadata + * @return bool One of the self::METADATA_(BAD|GOOD|COMPATIBLE) constants + */ + public function isMetadataValid( $file, $metadata ) { + if ( !$metadata ) { + // Old metadata when we just put an empty string in there + return self::METADATA_BAD; + } else { + return self::METADATA_GOOD; + } + } + + /** + * Must use "im" for XCF + * + * @param string $dstPath + * @param bool $checkDstPath + * @return string + */ + protected function getScalerType( $dstPath, $checkDstPath = true ) { + return "im"; + } + + /** + * Can we render this file? + * + * Image magick doesn't support indexed xcf files as of current + * writing (as of 6.8.9-3) + * @param File $file + * @return bool + */ + public function canRender( $file ) { + Wikimedia\suppressWarnings(); + $xcfMeta = unserialize( $file->getMetadata() ); + Wikimedia\restoreWarnings(); + if ( isset( $xcfMeta['colorType'] ) && $xcfMeta['colorType'] === 'index-coloured' ) { + return false; + } + return parent::canRender( $file ); + } +} |