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-rw-r--r--includes/media/ExifBitmap.php210
1 files changed, 210 insertions, 0 deletions
diff --git a/includes/media/ExifBitmap.php b/includes/media/ExifBitmap.php
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+<?php
+/**
+ * @file
+ * @ingroup Media
+ */
+
+/**
+ * Stuff specific to JPEG and (built-in) TIFF handler.
+ * All metadata related, since both JPEG and TIFF support Exif.
+ *
+ * @ingroup Media
+ */
+class ExifBitmapHandler extends BitmapHandler {
+
+ const BROKEN_FILE = '-1'; // error extracting metadata
+ const OLD_BROKEN_FILE = '0'; // outdated error extracting metadata.
+
+ function convertMetadataVersion( $metadata, $version = 1 ) {
+ // basically flattens arrays.
+ $version = explode(';', $version, 2);
+ $version = intval($version[0]);
+ if ( $version < 1 || $version >= 2 ) {
+ return $metadata;
+ }
+
+ $avoidHtml = true;
+
+ if ( !is_array( $metadata ) ) {
+ $metadata = unserialize( $metadata );
+ }
+ if ( !isset( $metadata['MEDIAWIKI_EXIF_VERSION'] ) || $metadata['MEDIAWIKI_EXIF_VERSION'] != 2 ) {
+ return $metadata;
+ }
+
+ // Treat Software as a special case because in can contain
+ // an array of (SoftwareName, Version).
+ if (isset( $metadata['Software'] )
+ && is_array( $metadata['Software'] )
+ && is_array( $metadata['Software'][0])
+ && isset( $metadata['Software'][0][0] )
+ && isset( $metadata['Software'][0][1])
+ ) {
+ $metadata['Software'] = $metadata['Software'][0][0] . ' (Version '
+ . $metadata['Software'][0][1] . ')';
+ }
+
+ // ContactInfo also has to be dealt with specially
+ if ( isset( $metadata['Contact'] ) ) {
+ $metadata['Contact'] =
+ FormatMetadata::collapseContactInfo(
+ $metadata['Contact'] );
+ }
+
+ foreach ( $metadata as &$val ) {
+ if ( is_array( $val ) ) {
+ $val = FormatMetadata::flattenArray( $val, 'ul', $avoidHtml );
+ }
+ }
+ $metadata['MEDIAWIKI_EXIF_VERSION'] = 1;
+ return $metadata;
+ }
+
+ function isMetadataValid( $image, $metadata ) {
+ global $wgShowEXIF;
+ if ( !$wgShowEXIF ) {
+ # Metadata disabled and so an empty field is expected
+ return self::METADATA_GOOD;
+ }
+ if ( $metadata === self::OLD_BROKEN_FILE ) {
+ # Old special value indicating that there is no EXIF data in the file.
+ # or that there was an error well extracting the metadata.
+ wfDebug( __METHOD__ . ": back-compat version\n");
+ return self::METADATA_COMPATIBLE;
+ }
+ if ( $metadata === self::BROKEN_FILE ) {
+ return self::METADATA_GOOD;
+ }
+ wfSuppressWarnings();
+ $exif = unserialize( $metadata );
+ wfRestoreWarnings();
+ if ( !isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) ||
+ $exif['MEDIAWIKI_EXIF_VERSION'] != Exif::version() )
+ {
+ if ( isset( $exif['MEDIAWIKI_EXIF_VERSION'] ) &&
+ $exif['MEDIAWIKI_EXIF_VERSION'] == 1 )
+ {
+ //back-compatible but old
+ wfDebug( __METHOD__.": back-compat version\n" );
+ return self::METADATA_COMPATIBLE;
+ }
+ # Wrong (non-compatible) version
+ wfDebug( __METHOD__.": wrong version\n" );
+ return self::METADATA_BAD;
+ }
+ return self::METADATA_GOOD;
+ }
+
+ /**
+ * @param $image File
+ * @return array|bool
+ */
+ function formatMetadata( $image ) {
+ $metadata = $image->getMetadata();
+ if ( $metadata === self::OLD_BROKEN_FILE ||
+ $metadata === self::BROKEN_FILE ||
+ $this->isMetadataValid( $image, $metadata ) === self::METADATA_BAD )
+ {
+ // So we don't try and display metadata from PagedTiffHandler
+ // for example when using InstantCommons.
+ return false;
+ }
+
+ $exif = unserialize( $metadata );
+ if ( !$exif ) {
+ return false;
+ }
+ unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
+ if ( count( $exif ) == 0 ) {
+ return false;
+ }
+ return $this->formatMetadataHelper( $exif );
+ }
+
+ function getMetadataType( $image ) {
+ return 'exif';
+ }
+
+ /**
+ * Wrapper for base classes ImageHandler::getImageSize() that checks for
+ * rotation reported from metadata and swaps the sizes to match.
+ *
+ * @param File $image
+ * @param string $path
+ * @return array
+ */
+ function getImageSize( $image, $path ) {
+ global $wgEnableAutoRotation;
+ $gis = parent::getImageSize( $image, $path );
+
+ // Don't just call $image->getMetadata(); File::getPropsFromPath() calls us with a bogus object.
+ // This may mean we read EXIF data twice on initial upload.
+ if ( $wgEnableAutoRotation ) {
+ $meta = $this->getMetadata( $image, $path );
+ $rotation = $this->getRotationForExif( $meta );
+ } else {
+ $rotation = 0;
+ }
+
+ if ($rotation == 90 || $rotation == 270) {
+ $width = $gis[0];
+ $gis[0] = $gis[1];
+ $gis[1] = $width;
+ }
+ return $gis;
+ }
+
+ /**
+ * On supporting image formats, try to read out the low-level orientation
+ * of the file and return the angle that the file needs to be rotated to
+ * be viewed.
+ *
+ * This information is only useful when manipulating the original file;
+ * the width and height we normally work with is logical, and will match
+ * any produced output views.
+ *
+ * @param $file File
+ * @return int 0, 90, 180 or 270
+ */
+ public function getRotation( $file ) {
+ global $wgEnableAutoRotation;
+ if ( !$wgEnableAutoRotation ) {
+ return 0;
+ }
+
+ $data = $file->getMetadata();
+ return $this->getRotationForExif( $data );
+ }
+
+ /**
+ * Given a chunk of serialized Exif metadata, return the orientation as
+ * degrees of rotation.
+ *
+ * @param string $data
+ * @return int 0, 90, 180 or 270
+ * @fixme orientation can include flipping as well; see if this is an issue!
+ */
+ protected function getRotationForExif( $data ) {
+ if ( !$data ) {
+ return 0;
+ }
+ wfSuppressWarnings();
+ $data = unserialize( $data );
+ wfRestoreWarnings();
+ if ( isset( $data['Orientation'] ) ) {
+ # See http://sylvana.net/jpegcrop/exif_orientation.html
+ switch ( $data['Orientation'] ) {
+ case 8:
+ return 90;
+ case 3:
+ return 180;
+ case 6:
+ return 270;
+ default:
+ return 0;
+ }
+ }
+ return 0;
+ }
+}
+