function getMetadata($image, $filename)
{
if (!isset($image->parsedGIFMetadata)) {
try {
$image->parsedGIFMetadata = GIFMetadataExtractor::getMetadata($filename);
} catch (Exception $e) {
// Broken file?
wfDebug(__METHOD__ . ': ' . $e->getMessage() . "\n");
return '0';
}
}
return serialize($image->parsedGIFMetadata);
}
/**
* Put in a file, and see if the metadata coming out is as expected.
* @param $filename String
* @param $expected Array The extracted metadata.
* @dataProvider provideGetMetadata
*/
public function testGetMetadata($filename, $expected)
{
$actual = GIFMetadataExtractor::getMetadata($this->mediaPath . $filename);
$this->assertEquals($expected, $actual);
}
static function getMetadata($filename)
{
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) {
throw new Exception("No file name specified");
} elseif (!file_exists($filename) || is_dir($filename)) {
throw new Exception("File {$filename} does not exist");
}
$fh = fopen($filename, 'r');
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);
self::skipBlock($fh);
} elseif ($buf == self::$gif_extension_sep) {
$buf = fread($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) {
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 ($data != "") {
throw new Exception("Expected , got {$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 {
self::skipBlock($fh);
}
} elseif ($buf == self::$gif_term) {
break;
} else {
$byte = unpack('C', $buf);
$byte = $byte[1];
throw new Exception("At position: " . ftell($fh) . ", Unknown byte " . $byte);
}
}
return array('frameCount' => $frameCount, 'looped' => $isLooped, 'duration' => $duration);
}
/** 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(array('GIFFileComment' => $baseArray['comment']), 'native');
}
if ($baseArray['xmp'] !== '' && function_exists('xml_parser_create_ns')) {
$xmp = new XMPReader();
$xmp->parse($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;
}
/**
* @throws Exception
* @param $filename string
* @return array
*/
static function getMetadata($filename)
{
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;
$xmp = "";
$comment = array();
if (!$filename) {
throw new Exception("No file name specified");
} elseif (!file_exists($filename) || is_dir($filename)) {
throw new Exception("File {$filename} does not exist");
}
$fh = fopen($filename, 'rb');
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);
self::skipBlock($fh);
} elseif ($buf == self::$gif_extension_sep) {
$buf = fread($fh, 1);
if (strlen($buf) < 1) {
throw new Exception("Ran out of input");
}
$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.
if (strlen($buf) < 2) {
throw new Exception("Ran out of input");
}
$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
if (strlen($term) < 1) {
throw new Exception("Ran out of input");
}
$term = unpack('C', $term);
$term = $term[1];
if ($term != 0) {
throw new Exception("Malformed Graphics Control Extension block");
}
} elseif ($extension_code == 0xfe) {
// Comment block(s).
$data = self::readBlock($fh);
if ($data === "") {
throw new Exception('Read error, zero-length comment block');
}
// The standard says this should be ASCII, however its unclear if
// thats true in practise. Check to see if its valid utf-8, if so
// assume its that, otherwise assume its windows-1252 (iso-8859-1)
$dataCopy = $data;
// quickIsNFCVerify has the side effect of replacing any invalid characters
UtfNormal::quickIsNFCVerify($dataCopy);
if ($dataCopy !== $data) {
wfSuppressWarnings();
$data = iconv('windows-1252', 'UTF-8', $data);
wfRestoreWarnings();
}
$commentCount = count($comment);
if ($commentCount === 0 || $comment[$commentCount - 1] !== $data) {
// Some applications repeat the same comment on each
// frame of an animated GIF image, so if this comment
// is identical to the last, only extract once.
$comment[] = $data;
}
} elseif ($extension_code == 0xff) {
// Application extension (Netscape info about the animated gif)
// or XMP (or theoretically any other type of extension block)
$blockLength = fread($fh, 1);
if (strlen($blockLength) < 1) {
throw new Exception("Ran out of input");
}
$blockLength = unpack('C', $blockLength);
$blockLength = $blockLength[1];
$data = fread($fh, $blockLength);
if ($blockLength != 11) {
wfDebug(__METHOD__ . ' GIF application block with wrong length');
fseek($fh, -($blockLength + 1), SEEK_CUR);
self::skipBlock($fh);
continue;
}
// NETSCAPE2.0 (application name for animated gif)
if ($data == 'NETSCAPE2.0') {
$data = fread($fh, 2);
// Block length and introduction, should be 03 01
if ($data != "") {
throw new Exception("Expected , got {$data}");
}
// Unsigned little-endian integer, loop count or zero for "forever"
$loopData = fread($fh, 2);
if (strlen($loopData) < 2) {
throw new Exception("Ran out of input");
}
$loopData = unpack('v', $loopData);
$loopCount = $loopData[1];
if ($loopCount != 1) {
$isLooped = true;
}
// Read out terminator byte
fread($fh, 1);
} elseif ($data == 'XMP DataXMP') {
// application name for XMP data.
// see pg 18 of XMP spec part 3.
$xmp = self::readBlock($fh, true);
if (substr($xmp, -257, 3) !== "ÿþ" || substr($xmp, -4) !== "") {
// this is just a sanity check.
throw new Exception("XMP does not have magic trailer!");
}
// strip out trailer.
$xmp = substr($xmp, 0, -257);
} else {
// unrecognized extension block
fseek($fh, -($blockLength + 1), SEEK_CUR);
self::skipBlock($fh);
continue;
}
} else {
self::skipBlock($fh);
}
} elseif ($buf == self::$gif_term) {
break;
} else {
if (strlen($buf) < 1) {
throw new Exception("Ran out of input");
}
$byte = unpack('C', $buf);
$byte = $byte[1];
throw new Exception("At position: " . ftell($fh) . ", Unknown byte " . $byte);
}
}
return array('frameCount' => $frameCount, 'looped' => $isLooped, 'duration' => $duration, 'xmp' => $xmp, 'comment' => $comment);
}
/** 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;
}
