--- /dev/null
+<?php
+/**
+ * Extraction of metadata from different bitmap image types.
+ *
+ * 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
+ */
+
+use MediaWiki\Logger\LoggerFactory;
+
+/**
+ * Class to deal with reconciling and extracting metadata from bitmap images.
+ * This is meant to comply with http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
+ *
+ * This sort of acts as an intermediary between MediaHandler::getMetadata
+ * and the various metadata extractors.
+ *
+ * @todo Other image formats.
+ * @ingroup Media
+ */
+class BitmapMetadataHandler {
+ /** @var array */
+ private $metadata = [];
+
+ /** @var array Metadata priority */
+ private $metaPriority = [
+ 20 => [ 'other' ],
+ 40 => [ 'native' ],
+ 60 => [ 'iptc-good-hash', 'iptc-no-hash' ],
+ 70 => [ 'xmp-deprecated' ],
+ 80 => [ 'xmp-general' ],
+ 90 => [ 'xmp-exif' ],
+ 100 => [ 'iptc-bad-hash' ],
+ 120 => [ 'exif' ],
+ ];
+
+ /** @var string */
+ private $iptcType = 'iptc-no-hash';
+
+ /**
+ * This does the photoshop image resource app13 block
+ * of interest, IPTC-IIM metadata is stored here.
+ *
+ * Mostly just calls doPSIR and doIPTC
+ *
+ * @param string $app13 String containing app13 block from jpeg file
+ */
+ private function doApp13( $app13 ) {
+ try {
+ $this->iptcType = JpegMetadataExtractor::doPSIR( $app13 );
+ } catch ( Exception $e ) {
+ // Error reading the iptc hash information.
+ // This probably means the App13 segment is something other than what we expect.
+ // However, still try to read it, and treat it as if the hash didn't exist.
+ wfDebug( "Error parsing iptc data of file: " . $e->getMessage() . "\n" );
+ $this->iptcType = 'iptc-no-hash';
+ }
+
+ $iptc = IPTC::parse( $app13 );
+ $this->addMetadata( $iptc, $this->iptcType );
+ }
+
+ /**
+ * Get exif info using exif class.
+ * Basically what used to be in BitmapHandler::getMetadata().
+ * Just calls stuff in the Exif class.
+ *
+ * Parameters are passed to the Exif class.
+ *
+ * @param string $filename
+ * @param string $byteOrder
+ */
+ function getExif( $filename, $byteOrder ) {
+ global $wgShowEXIF;
+ if ( file_exists( $filename ) && $wgShowEXIF ) {
+ $exif = new Exif( $filename, $byteOrder );
+ $data = $exif->getFilteredData();
+ if ( $data ) {
+ $this->addMetadata( $data, 'exif' );
+ }
+ }
+ }
+
+ /** Add misc metadata. Warning: atm if the metadata category
+ * doesn't have a priority, it will be silently discarded.
+ *
+ * @param array $metaArray Array of metadata values
+ * @param string $type Type. defaults to other. if two things have the same type they're merged
+ */
+ function addMetadata( $metaArray, $type = 'other' ) {
+ if ( isset( $this->metadata[$type] ) ) {
+ /* merge with old data */
+ $metaArray = $metaArray + $this->metadata[$type];
+ }
+
+ $this->metadata[$type] = $metaArray;
+ }
+
+ /**
+ * Merge together the various types of metadata
+ * the different types have different priorites,
+ * and are merged in order.
+ *
+ * This function is generally called by the media handlers' getMetadata()
+ *
+ * @return array Metadata array
+ */
+ function getMetadataArray() {
+ // this seems a bit ugly... This is all so its merged in right order
+ // based on the MWG recomendation.
+ $temp = [];
+ krsort( $this->metaPriority );
+ foreach ( $this->metaPriority as $pri ) {
+ foreach ( $pri as $type ) {
+ if ( isset( $this->metadata[$type] ) ) {
+ // Do some special casing for multilingual values.
+ // Don't discard translations if also as a simple value.
+ foreach ( $this->metadata[$type] as $itemName => $item ) {
+ if ( is_array( $item ) && isset( $item['_type'] ) && $item['_type'] === 'lang' ) {
+ if ( isset( $temp[$itemName] ) && !is_array( $temp[$itemName] ) ) {
+ $default = $temp[$itemName];
+ $temp[$itemName] = $item;
+ $temp[$itemName]['x-default'] = $default;
+ unset( $this->metadata[$type][$itemName] );
+ }
+ }
+ }
+
+ $temp = $temp + $this->metadata[$type];
+ }
+ }
+ }
+
+ return $temp;
+ }
+
+ /** Main entry point for jpeg's.
+ *
+ * @param string $filename Filename (with full path)
+ * @return array Metadata result array.
+ * @throws MWException On invalid file.
+ */
+ static function Jpeg( $filename ) {
+ $showXMP = XMPReader::isSupported();
+ $meta = new self();
+
+ $seg = JpegMetadataExtractor::segmentSplitter( $filename );
+
+ if ( isset( $seg['COM'] ) && isset( $seg['COM'][0] ) ) {
+ $meta->addMetadata( [ 'JPEGFileComment' => $seg['COM'] ], 'native' );
+ }
+ if ( isset( $seg['PSIR'] ) && count( $seg['PSIR'] ) > 0 ) {
+ foreach ( $seg['PSIR'] as $curPSIRValue ) {
+ $meta->doApp13( $curPSIRValue );
+ }
+ }
+ if ( isset( $seg['XMP'] ) && $showXMP ) {
+ $xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ) );
+ $xmp->parse( $seg['XMP'] );
+ foreach ( $seg['XMP_ext'] as $xmpExt ) {
+ /* Support for extended xmp in jpeg files
+ * is not well tested and a bit fragile.
+ */
+ $xmp->parseExtended( $xmpExt );
+ }
+ $res = $xmp->getResults();
+ foreach ( $res as $type => $array ) {
+ $meta->addMetadata( $array, $type );
+ }
+ }
+
+ $meta->getExif( $filename, isset( $seg['byteOrder'] ) ? $seg['byteOrder'] : 'BE' );
+
+ return $meta->getMetadataArray();
+ }
+
+ /** Entry point for png
+ * At some point in the future this might
+ * merge the png various tEXt chunks to that
+ * are interesting, but for now it only does XMP
+ *
+ * @param string $filename Full path to file
+ * @return array Array for storage in img_metadata.
+ */
+ public static function PNG( $filename ) {
+ $showXMP = XMPReader::isSupported();
+
+ $meta = new self();
+ $array = PNGMetadataExtractor::getMetadata( $filename );
+ if ( isset( $array['text']['xmp']['x-default'] )
+ && $array['text']['xmp']['x-default'] !== '' && $showXMP
+ ) {
+ $xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ) );
+ $xmp->parse( $array['text']['xmp']['x-default'] );
+ $xmpRes = $xmp->getResults();
+ foreach ( $xmpRes as $type => $xmpSection ) {
+ $meta->addMetadata( $xmpSection, $type );
+ }
+ }
+ unset( $array['text']['xmp'] );
+ $meta->addMetadata( $array['text'], 'native' );
+ unset( $array['text'] );
+ $array['metadata'] = $meta->getMetadataArray();
+ $array['metadata']['_MW_PNG_VERSION'] = PNGMetadataExtractor::VERSION;
+
+ return $array;
+ }
+
+ /** function for gif images.
+ *
+ * They don't really have native metadata, so just merges together
+ * XMP and image comment.
+ *
+ * @param string $filename Full path to file
+ * @return array Metadata array
+ */
+ public static function GIF( $filename ) {
+ $meta = new self();
+ $baseArray = GIFMetadataExtractor::getMetadata( $filename );
+
+ if ( count( $baseArray['comment'] ) > 0 ) {
+ $meta->addMetadata( [ 'GIFFileComment' => $baseArray['comment'] ], 'native' );
+ }
+
+ if ( $baseArray['xmp'] !== '' && XMPReader::isSupported() ) {
+ $xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ) );
+ $xmp->parse( $baseArray['xmp'] );
+ $xmpRes = $xmp->getResults();
+ foreach ( $xmpRes as $type => $xmpSection ) {
+ $meta->addMetadata( $xmpSection, $type );
+ }
+ }
+
+ unset( $baseArray['comment'] );
+ unset( $baseArray['xmp'] );
+
+ $baseArray['metadata'] = $meta->getMetadataArray();
+ $baseArray['metadata']['_MW_GIF_VERSION'] = GIFMetadataExtractor::VERSION;
+
+ return $baseArray;
+ }
+
+ /**
+ * This doesn't do much yet, but eventually I plan to add
+ * XMP support for Tiff. (PHP's exif support already extracts
+ * but needs some further processing because PHP's exif support
+ * is stupid...)
+ *
+ * @todo Add XMP support, so this function actually makes sense to put here.
+ *
+ * The various exceptions this throws are caught later.
+ * @param string $filename
+ * @throws MWException
+ * @return array The metadata.
+ */
+ public static function Tiff( $filename ) {
+ if ( file_exists( $filename ) ) {
+ $byteOrder = self::getTiffByteOrder( $filename );
+ if ( !$byteOrder ) {
+ throw new MWException( "Error determining byte order of $filename" );
+ }
+ $exif = new Exif( $filename, $byteOrder );
+ $data = $exif->getFilteredData();
+ if ( $data ) {
+ $data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
+
+ return $data;
+ } else {
+ throw new MWException( "Could not extract data from tiff file $filename" );
+ }
+ } else {
+ throw new MWException( "File doesn't exist - $filename" );
+ }
+ }
+
+ /**
+ * Read the first 2 bytes of a tiff file to figure out
+ * Little Endian or Big Endian. Needed for exif stuff.
+ *
+ * @param string $filename The filename
+ * @return string 'BE' or 'LE' or false
+ */
+ static function getTiffByteOrder( $filename ) {
+ $fh = fopen( $filename, 'rb' );
+ if ( !$fh ) {
+ return false;
+ }
+ $head = fread( $fh, 2 );
+ fclose( $fh );
+
+ switch ( $head ) {
+ case 'II':
+ return 'LE'; // II for intel.
+ case 'MM':
+ return 'BE'; // MM for motorla.
+ default:
+ return false; // Something went wrong.
+
+ }
+ }
+}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff