/**
* swaps the index from end to beginning
*
* swaps the index from end to beginning
*
* @return mixed True if everything wents fine, otherwise error-message as string
* @author Benjamin Carl <*****@*****.**>
* @version 0.1
* @since Method available since Release 0.1
* @access private
*/
private function _swapIndex()
{
$moovSize = $this->_moovBytes->bytesAvailable();
$moovAType = '';
$moovASize = 0;
$offsetCount = 0;
$compressionCheck = $this->_moovBytes->readBytes(12, 4);
if ($compressionCheck == Atom::CMOV_ATOM) {
throw new Exception('compressed MP4/QT-file can\'t do this file: ' . $file);
}
// begin of metadata
$metaDataOffsets = array();
$metaDataStrings = array();
$metaDataCurrentLevel = 0;
$moovStartOffset = 12;
for ($i = $moovStartOffset; $i < $moovSize - $moovStartOffset; $i++) {
$moovAType = $this->_moovBytes->readUTFBytes($i, 4);
if (Atom::isValidAtom($moovAType)) {
$moovASize = $this->_moovBytes->readUnsignedInt($i - 4);
if ($moovASize > 8 && $moovASize + $i < $moovSize - $moovStartOffset) {
try {
$containerLength = 0;
$containerString = $moovAType;
for ($mi = count($metaDataOffsets) - 1; $mi > -1; $mi--) {
$containerLength = $metaDataOffsets[$mi];
if ($i - $moovStartOffset < $containerLength && $i - $moovStartOffset + $moovASize > $containerLength) {
throw new Exception('bad atom nested size');
}
if ($i - $moovStartOffset == $containerLength) {
array_pop($metaDataOffsets);
array_pop($metaDataStrings);
} else {
$containerString = $metaDataStrings[$mi] . "." . $containerString;
}
}
if ($i - $moovStartOffset <= $containerLength) {
array_push($metaDataOffsets, $i - $moovStartOffset + $moovASize);
array_push($metaDataStrings, $moovAType);
}
if ($moovAType != Atom::STCO_ATOM && $moovAType != Atom::CO64_ATOM) {
$i += 4;
} elseif ($moovAType == Atom::URL_ATOM || $moovAType == Atom::XML_ATOM) {
$i += $moovASize - 4;
}
} catch (Exception $e) {
echo 'EXCEPTION: ' . $e->getMessage();
}
}
}
if ($moovAType == Atom::STCO_ATOM) {
$moovASize = $this->_moovBytes->readUnsignedInt($i - 4);
if ($i + $moovASize - $moovStartOffset > $moovSize) {
throw new Exception('bad atom size');
return;
}
$offsetCount = $this->_moovBytes->readUnsignedInt($i + 8);
for ($j = 0; $j < $offsetCount; $j++) {
$position = $i + 12 + $j * 4;
$currentOffset = $this->_moovBytes->readUnsignedInt($position);
// cause of mooving the moov-atom right before the rest of data
// (behind ftyp) the new offset is caluclated:
// current-offset + size of moov atom (box) = new offset
$currentOffset += $moovSize;
$this->_moovBytes->writeBytes(Transform::toUInt32BE($currentOffset), $position + 1);
}
$i += $moovASize - 4;
} else {
if ($moovAType == Atom::CO64_ATOM) {
$moovASize = $this->_moovBytes->readUnsignedInt($i - 4);
if ($i + $moovASize - $moovStartOffset > $moovSize) {
throw new Exception('bad atom size');
return;
}
$offsetCount = $this->_moovBytes->readDouble($i + 8);
for ($j2 = 0; $j2 < $offsetCount; $j2++) {
$position = $i + 12 + $j * 8;
$currentOffset = $this->_moovBytes->readUnsignedInt($position);
// cause of mooving the moov-atom right before the rest of data
// (behind ftyp) the new offset is caluclated:
// current-offset + size of moov atom (box) = new offset
$currentOffset += $moovSize;
// TODO implement!
//$this->_moovBytes->writeBytes(Transform::toUInt64BE($currentOffset), $position+1);
}
$i += $moovASize - 4;
}
}
}
return true;
}
