/** 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'] !== '' && 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;
}
/** Function to extract metadata segments of interest from jpeg files
* based on GIFMetadataExtractor.
*
* we can almost use getimagesize to do this
* but gis doesn't support having multiple app1 segments
* and those can't extract xmp on files containing both exif and xmp data
*
* @param string $filename Name of jpeg file
* @return array Array of interesting segments.
* @throws MWException If given invalid file.
*/
static function segmentSplitter($filename)
{
$showXMP = XMPReader::isSupported();
$segmentCount = 0;
$segments = array('XMP_ext' => array(), 'COM' => array(), 'PSIR' => array());
if (!$filename) {
throw new MWException("No filename specified for " . __METHOD__);
}
if (!file_exists($filename) || is_dir($filename)) {
throw new MWException("Invalid file {$filename} passed to " . __METHOD__);
}
$fh = fopen($filename, "rb");
if (!$fh) {
throw new MWException("Could not open file {$filename}");
}
$buffer = fread($fh, 2);
if ($buffer !== "ÿØ") {
throw new MWException("Not a jpeg, no SOI");
}
while (!feof($fh)) {
$buffer = fread($fh, 1);
$segmentCount++;
if ($segmentCount > self::MAX_JPEG_SEGMENTS) {
// this is just a sanity check
throw new MWException('Too many jpeg segments. Aborting');
}
if ($buffer !== "ÿ") {
throw new MWException("Error reading jpeg file marker. " . "Expected 0xFF but got " . bin2hex($buffer));
}
$buffer = fread($fh, 1);
while ($buffer === "ÿ" && !feof($fh)) {
// Skip through any 0xFF padding bytes.
$buffer = fread($fh, 1);
}
if ($buffer === "þ") {
// COM section -- file comment
// First see if valid utf-8,
// if not try to convert it to windows-1252.
$com = $oldCom = trim(self::jpegExtractMarker($fh));
UtfNormal::quickIsNFCVerify($com);
// turns $com to valid utf-8.
// thus if no change, its utf-8, otherwise its something else.
if ($com !== $oldCom) {
wfSuppressWarnings();
$com = $oldCom = iconv('windows-1252', 'UTF-8//IGNORE', $oldCom);
wfRestoreWarnings();
}
// Try it again, if its still not a valid string, then probably
// binary junk or some really weird encoding, so don't extract.
UtfNormal::quickIsNFCVerify($com);
if ($com === $oldCom) {
$segments["COM"][] = $oldCom;
} else {
wfDebug(__METHOD__ . " Ignoring JPEG comment as is garbage.\n");
}
} elseif ($buffer === "á") {
// APP1 section (Exif, XMP, and XMP extended)
// only extract if XMP is enabled.
$temp = self::jpegExtractMarker($fh);
// check what type of app segment this is.
if (substr($temp, 0, 29) === "http://ns.adobe.com/xap/1.0/" && $showXMP) {
$segments["XMP"] = substr($temp, 29);
} elseif (substr($temp, 0, 35) === "http://ns.adobe.com/xmp/extension/" && $showXMP) {
$segments["XMP_ext"][] = substr($temp, 35);
} elseif (substr($temp, 0, 29) === "XMP://ns.adobe.com/xap/1.0/" && $showXMP) {
// Some images (especially flickr images) seem to have this.
// I really have no idea what the deal is with them, but
// whatever...
$segments["XMP"] = substr($temp, 29);
wfDebug(__METHOD__ . ' Found XMP section with wrong app identifier ' . "Using anyways.\n");
} elseif (substr($temp, 0, 6) === "Exif") {
// Just need to find out what the byte order is.
// because php's exif plugin sucks...
// This is a II for little Endian, MM for big. Not a unicode BOM.
$byteOrderMarker = substr($temp, 6, 2);
if ($byteOrderMarker === 'MM') {
$segments['byteOrder'] = 'BE';
} elseif ($byteOrderMarker === 'II') {
$segments['byteOrder'] = 'LE';
} else {
wfDebug(__METHOD__ . " Invalid byte ordering?!\n");
}
}
} elseif ($buffer === "í") {
// APP13 - PSIR. IPTC and some photoshop stuff
$temp = self::jpegExtractMarker($fh);
if (substr($temp, 0, 14) === "Photoshop 3.0") {
$segments["PSIR"][] = $temp;
}
} elseif ($buffer === "Ù" || $buffer === "Ú") {
// EOI - end of image or SOS - start of scan. either way we're past any interesting segments
return $segments;
} else {
// segment we don't care about, so skip
$size = wfUnpack("nint", fread($fh, 2), 2);
if ($size['int'] <= 2) {
throw new MWException("invalid marker size in jpeg");
}
fseek($fh, $size['int'] - 2, SEEK_CUR);
}
}
// shouldn't get here.
throw new MWException("Reached end of jpeg file unexpectedly");
}
