<?php
/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <[email protected]> //
// available at http://getid3.sourceforge.net //
// or http://www.getid3.org //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details //
/////////////////////////////////////////////////////////////////
// //
// module.audio.shorten.php //
// module for analyzing Shorten Audio files //
// dependencies: NONE //
// ///
/////////////////////////////////////////////////////////////////
class getid3_rkau extends getid3_handler
{
function Analyze() {
$info = &$this->getid3->info;
fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
$RKAUHeader = fread($this->getid3->fp, 20);
$magic = 'RKA';
if (substr($RKAUHeader, 0, 3) != $magic) {
$info['error'][] = 'Expecting "'.getid3_lib::PrintHexBytes($magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes(substr($RKAUHeader, 0, 3)).'"';
return false;
}
$info['fileformat'] = 'rkau';
$info['audio']['dataformat'] = 'rkau';
$info['audio']['bitrate_mode'] = 'vbr';
$info['rkau']['raw']['version'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 3, 1));
$info['rkau']['version'] = '1.'.str_pad($info['rkau']['raw']['version'] & 0x0F, 2, '0', STR_PAD_LEFT);
if (($info['rkau']['version'] > 1.07) || ($info['rkau']['version'] < 1.06)) {
$info['error'][] = 'This version of getID3() ['.$this->getid3->version().'] can only parse RKAU files v1.06 and 1.07 (this file is v'.$info['rkau']['version'].')';
unset($info['rkau']);
return false;
}
$info['rkau']['source_bytes'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 4, 4));
$info['rkau']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 8, 4));
$info['rkau']['channels'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 12, 1));
$info['rkau']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 13, 1));
$info['rkau']['raw']['quality'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 14, 1));
$this->RKAUqualityLookup($info['rkau']);
$info['rkau']['raw']['flags'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 15, 1));
$info['rkau']['flags']['joint_stereo'] = (bool) (!($info['rkau']['raw']['flags'] & 0x01));
$info['rkau']['flags']['streaming'] = (bool) ($info['rkau']['raw']['flags'] & 0x02);
$info['rkau']['flags']['vrq_lossy_mode'] = (bool) ($info['rkau']['raw']['flags'] & 0x04);
if ($info['rkau']['flags']['streaming']) {
$info['avdataoffset'] += 20;
$info['rkau']['compressed_bytes'] = getid3_lib::LittleEndian2Int(substr($RKAUHeader, 16, 4));
} else {
$info['avdataoffset'] += 16;
$info['rkau']['compressed_bytes'] = $info['avdataend'] - $info['avdataoffset'] - 1;
}
// Note: compressed_bytes does not always equal what appears to be the actual number of compressed bytes,
// sometimes it's more, sometimes less. No idea why(?)
$info['audio']['lossless'] = $info['rkau']['lossless'];
$info['audio']['channels'] = $info['rkau']['channels'];
$info['audio']['bits_per_sample'] = $info['rkau']['bits_per_sample'];
$info['audio']['sample_rate'] = $info['rkau']['sample_rate'];
$info['playtime_seconds'] = $info['rkau']['source_bytes'] / ($info['rkau']['sample_rate'] * $info['rkau']['channels'] * ($info['rkau']['bits_per_sample'] / 8));
$info['audio']['bitrate'] = ($info['rkau']['compressed_bytes'] * 8) / $info['playtime_seconds'];
return true;
}
function RKAUqualityLookup(&$RKAUdata) {
$level = ($RKAUdata['raw']['quality'] & 0xF0) >> 4;
$quality = $RKAUdata['raw']['quality'] & 0x0F;
$RKAUdata['lossless'] = (($quality == 0) ? true : false);
$RKAUdata['compression_level'] = $level + 1;
if (!$RKAUdata['lossless']) {
$RKAUdata['quality_setting'] = $quality;
}
return true;
}
}
?>
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