* @ingroup Media
*/
class GIFHandler extends BitmapHandler {
-
+
function getMetadata( $image, $filename ) {
if ( !isset( $image->parsedGIFMetadata ) ) {
try {
}
return serialize( $image->parsedGIFMetadata );
-
}
-
+
function formatMetadata( $image ) {
return false;
}
$ser = $image->getMetadata();
if ($ser) {
$metadata = unserialize($ser);
- if( $metadata['frameCount'] > 1 ) return true;
+ if( $metadata['frameCount'] > 1 ) {
+ return true;
+ }
}
return false;
}
-
+
function getMetadataType( $image ) {
return 'parsed-gif';
}
-
+
function isMetadataValid( $image, $metadata ) {
wfSuppressWarnings();
$data = unserialize( $metadata );
$metadata = unserialize($image->getMetadata());
wfRestoreWarnings();
- if (!$metadata || $metadata['frameCount'] <= 1)
+ if (!$metadata || $metadata['frameCount'] <= 1) {
return $original;
+ }
/* Preserve original image info string, but strip the last char ')' so we can add even more */
$info = array();
$info[] = $original;
- if ($metadata['looped'])
+ if ( $metadata['looped'] ) {
$info[] = wfMsgExt( 'file-info-gif-looped', 'parseinline' );
+ }
- if ($metadata['frameCount'] > 1)
+ if ( $metadata['frameCount'] > 1 ) {
$info[] = wfMsgExt( 'file-info-gif-frames', 'parseinline', $metadata['frameCount'] );
+ }
- if ($metadata['duration'])
+ if ( $metadata['duration'] ) {
$info[] = $wgLang->formatTimePeriod( $metadata['duration'] );
+ }
return $wgLang->commaList( $info );
}
self::$gif_frame_sep = pack( "C", ord("," ) );
self::$gif_extension_sep = pack( "C", ord("!" ) );
self::$gif_term = pack( "C", ord(";" ) );
-
+
$frameCount = 0;
$duration = 0.0;
$isLooped = false;
-
- if (!$filename)
+
+ if ( !$filename ) {
throw new Exception( "No file name specified" );
- elseif ( !file_exists($filename) || is_dir($filename) )
+ } elseif ( !file_exists( $filename ) || is_dir( $filename ) ) {
throw new Exception( "File $filename does not exist" );
-
+ }
+
$fh = fopen( $filename, 'r' );
-
- if (!$fh)
+
+ if ( !$fh ) {
throw new Exception( "Unable to open file $filename" );
-
+ }
+
// Check for the GIF header
$buf = fread( $fh, 6 );
if ( !($buf == 'GIF87a' || $buf == 'GIF89a') ) {
throw new Exception( "Not a valid GIF file; header: $buf" );
}
-
+
// Skip over width and height.
fread( $fh, 4 );
-
+
// Read BPP
$buf = fread( $fh, 1 );
$bpp = self::decodeBPP( $buf );
-
+
// Skip over background and aspect ratio
fread( $fh, 2 );
-
+
// Skip over the GCT
self::readGCT( $fh, $bpp );
-
+
while( !feof( $fh ) ) {
$buf = fread( $fh, 1 );
-
+
if ($buf == self::$gif_frame_sep) {
// Found a frame
$frameCount++;
-
+
## Skip bounding box
fread( $fh, 8 );
-
+
## Read BPP
$buf = fread( $fh, 1 );
$bpp = self::decodeBPP( $buf );
-
+
## Read GCT
self::readGCT( $fh, $bpp );
fread( $fh, 1 );
$buf = fread( $fh, 1 );
$extension_code = unpack( 'C', $buf );
$extension_code = $extension_code[1];
-
+
if ($extension_code == 0xF9) {
// Graphics Control Extension.
fread( $fh, 1 ); // Block size
-
+
fread( $fh, 1 ); // Transparency, disposal method, user input
-
+
$buf = fread( $fh, 2 ); // Delay, in hundredths of seconds.
$delay = unpack( 'v', $buf );
$delay = $delay[1];
$duration += $delay * 0.01;
-
+
fread( $fh, 1 ); // Transparent colour index
-
+
$term = fread( $fh, 1 ); // Should be a terminator
$term = unpack( 'C', $term );
$term = $term[1];
- if ($term != 0 )
+ if ($term != 0 ) {
throw new Exception( "Malformed Graphics Control Extension block" );
+ }
} elseif ($extension_code == 0xFF) {
// Application extension (Netscape info about the animated gif)
$blockLength = fread( $fh, 1 );
$blockLength = unpack( 'C', $blockLength );
$blockLength = $blockLength[1];
$data = fread( $fh, $blockLength );
-
+
// NETSCAPE2.0 (application name)
if ($blockLength != 11 || $data != 'NETSCAPE2.0') {
fseek( $fh, -($blockLength + 1), SEEK_CUR );
self::skipBlock( $fh );
continue;
}
-
+
$data = fread( $fh, 2 ); // Block length and introduction, should be 03 01
-
+
if ($data != "\x03\x01") {
throw new Exception( "Expected \x03\x01, got $data" );
}
-
+
// Unsigned little-endian integer, loop count or zero for "forever"
$loopData = fread( $fh, 2 );
$loopData = unpack( 'v', $loopData );
$loopCount = $loopData[1];
-
+
if ($loopCount != 1) {
$isLooped = true;
}
-
+
// Read out terminator byte
fread( $fh, 1 );
} else {
throw new Exception( "At position: ".ftell($fh). ", Unknown byte ".$byte );
}
}
-
+
return array(
'frameCount' => $frameCount,
'looped' => $isLooped,
'duration' => $duration
);
-
}
-
+
static function readGCT( $fh, $bpp ) {
- if ($bpp > 0) {
- for( $i=1; $i<=pow(2,$bpp); ++$i ) {
+ if ( $bpp > 0 ) {
+ for( $i=1; $i<=pow( 2, $bpp ); ++$i ) {
fread( $fh, 3 );
}
}
}
-
+
static function decodeBPP( $data ) {
$buf = unpack( 'C', $data );
$buf = $buf[1];
$bpp = ( $buf & 7 ) + 1;
$buf >>= 7;
-
+
$have_map = $buf & 1;
-
+
return $have_map ? $bpp : 0;
}
-
+
static function skipBlock( $fh ) {
while ( !feof( $fh ) ) {
$buf = fread( $fh, 1 );
$block_len = unpack( 'C', $buf );
$block_len = $block_len[1];
- if ($block_len == 0)
+ if ($block_len == 0) {
return;
+ }
fread( $fh, $block_len );
}
}
-
}