Syntax Syntax
Return Return
(bool)
Source Source
File: wp-includes/ID3/module.audio.mp3.php
$nextoffset += $framelength;
}
if (count($ActualFrameLengthValues) > 0) {
$framelength = intval(round(array_sum($ActualFrameLengthValues) / count($ActualFrameLengthValues)));
}
}
return $framelength;
}
/**
* @return bool
*/
public function getOnlyMPEGaudioInfoBruteForce() {
$MPEGaudioHeaderDecodeCache = array();
$MPEGaudioHeaderValidCache = array();
$MPEGaudioHeaderLengthCache = array();
$MPEGaudioVersionLookup = self::MPEGaudioVersionArray();
$MPEGaudioLayerLookup = self::MPEGaudioLayerArray();
$MPEGaudioBitrateLookup = self::MPEGaudioBitrateArray();
$MPEGaudioFrequencyLookup = self::MPEGaudioFrequencyArray();
$MPEGaudioChannelModeLookup = self::MPEGaudioChannelModeArray();
$MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
$MPEGaudioEmphasisLookup = self::MPEGaudioEmphasisArray();
$LongMPEGversionLookup = array();
$LongMPEGlayerLookup = array();
$LongMPEGbitrateLookup = array();
$LongMPEGpaddingLookup = array();
$LongMPEGfrequencyLookup = array();
$Distribution['bitrate'] = array();
$Distribution['frequency'] = array();
$Distribution['layer'] = array();
$Distribution['version'] = array();
$Distribution['padding'] = array();
$info = &$this->getid3->info;
$this->fseek($info['avdataoffset']);
$max_frames_scan = 5000;
$frames_scanned = 0;
$previousvalidframe = $info['avdataoffset'];
while ($this->ftell() < $info['avdataend']) {
set_time_limit(30);
$head4 = $this->fread(4);
if (strlen($head4) < 4) {
break;
}
if ($head4[0] != "\xFF") {
for ($i = 1; $i < 4; $i++) {
if ($head4[$i] == "\xFF") {
$this->fseek($i - 4, SEEK_CUR);
continue 2;
}
}
continue;
}
if (!isset($MPEGaudioHeaderDecodeCache[$head4])) {
$MPEGaudioHeaderDecodeCache[$head4] = self::MPEGaudioHeaderDecode($head4);
}
if (!isset($MPEGaudioHeaderValidCache[$head4])) {
$MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGaudioHeaderDecodeCache[$head4], false, false);
}
if ($MPEGaudioHeaderValidCache[$head4]) {
if (!isset($MPEGaudioHeaderLengthCache[$head4])) {
$LongMPEGversionLookup[$head4] = $MPEGaudioVersionLookup[$MPEGaudioHeaderDecodeCache[$head4]['version']];
$LongMPEGlayerLookup[$head4] = $MPEGaudioLayerLookup[$MPEGaudioHeaderDecodeCache[$head4]['layer']];
$LongMPEGbitrateLookup[$head4] = $MPEGaudioBitrateLookup[$LongMPEGversionLookup[$head4]][$LongMPEGlayerLookup[$head4]][$MPEGaudioHeaderDecodeCache[$head4]['bitrate']];
$LongMPEGpaddingLookup[$head4] = (bool) $MPEGaudioHeaderDecodeCache[$head4]['padding'];
$LongMPEGfrequencyLookup[$head4] = $MPEGaudioFrequencyLookup[$LongMPEGversionLookup[$head4]][$MPEGaudioHeaderDecodeCache[$head4]['sample_rate']];
$MPEGaudioHeaderLengthCache[$head4] = self::MPEGaudioFrameLength(
$LongMPEGbitrateLookup[$head4],
$LongMPEGversionLookup[$head4],
$LongMPEGlayerLookup[$head4],
$LongMPEGpaddingLookup[$head4],
$LongMPEGfrequencyLookup[$head4]);
}
if ($MPEGaudioHeaderLengthCache[$head4] > 4) {
$WhereWeWere = $this->ftell();
$this->fseek($MPEGaudioHeaderLengthCache[$head4] - 4, SEEK_CUR);
$next4 = $this->fread(4);
if ($next4[0] == "\xFF") {
if (!isset($MPEGaudioHeaderDecodeCache[$next4])) {
$MPEGaudioHeaderDecodeCache[$next4] = self::MPEGaudioHeaderDecode($next4);
}
if (!isset($MPEGaudioHeaderValidCache[$next4])) {
$MPEGaudioHeaderValidCache[$next4] = self::MPEGaudioHeaderValid($MPEGaudioHeaderDecodeCache[$next4], false, false);
}
if ($MPEGaudioHeaderValidCache[$next4]) {
$this->fseek(-4, SEEK_CUR);
$Distribution['bitrate'][$LongMPEGbitrateLookup[$head4]] = isset($Distribution['bitrate'][$LongMPEGbitrateLookup[$head4]]) ? ++$Distribution['bitrate'][$LongMPEGbitrateLookup[$head4]] : 1;
$Distribution['layer'][$LongMPEGlayerLookup[$head4]] = isset($Distribution['layer'][$LongMPEGlayerLookup[$head4]]) ? ++$Distribution['layer'][$LongMPEGlayerLookup[$head4]] : 1;
$Distribution['version'][$LongMPEGversionLookup[$head4]] = isset($Distribution['version'][$LongMPEGversionLookup[$head4]]) ? ++$Distribution['version'][$LongMPEGversionLookup[$head4]] : 1;
$Distribution['padding'][intval($LongMPEGpaddingLookup[$head4])] = isset($Distribution['padding'][intval($LongMPEGpaddingLookup[$head4])]) ? ++$Distribution['padding'][intval($LongMPEGpaddingLookup[$head4])] : 1;
$Distribution['frequency'][$LongMPEGfrequencyLookup[$head4]] = isset($Distribution['frequency'][$LongMPEGfrequencyLookup[$head4]]) ? ++$Distribution['frequency'][$LongMPEGfrequencyLookup[$head4]] : 1;
if (++$frames_scanned >= $max_frames_scan) {
$pct_data_scanned = ($this->ftell() - $info['avdataoffset']) / ($info['avdataend'] - $info['avdataoffset']);
$this->warning('too many MPEG audio frames to scan, only scanned first '.$max_frames_scan.' frames ('.number_format($pct_data_scanned * 100, 1).'% of file) and extrapolated distribution, playtime and bitrate may be incorrect.');
foreach ($Distribution as $key1 => $value1) {
foreach ($value1 as $key2 => $value2) {
$Distribution[$key1][$key2] = round($value2 / $pct_data_scanned);
}
}
break;
}
continue;
}
}
unset($next4);
$this->fseek($WhereWeWere - 3);
}
}
}
foreach ($Distribution as $key => $value) {
ksort($Distribution[$key], SORT_NUMERIC);
}
ksort($Distribution['version'], SORT_STRING);
$info['mpeg']['audio']['bitrate_distribution'] = $Distribution['bitrate'];
$info['mpeg']['audio']['frequency_distribution'] = $Distribution['frequency'];
$info['mpeg']['audio']['layer_distribution'] = $Distribution['layer'];
$info['mpeg']['audio']['version_distribution'] = $Distribution['version'];
$info['mpeg']['audio']['padding_distribution'] = $Distribution['padding'];
if (count($Distribution['version']) > 1) {
$this->error('Corrupt file - more than one MPEG version detected');
}
if (count($Distribution['layer']) > 1) {
$this->error('Corrupt file - more than one MPEG layer detected');
}
if (count($Distribution['frequency']) > 1) {
$this->error('Corrupt file - more than one MPEG sample rate detected');
}
$bittotal = 0;
foreach ($Distribution['bitrate'] as $bitratevalue => $bitratecount) {
if ($bitratevalue != 'free') {
$bittotal += ($bitratevalue * $bitratecount);
}
}
$info['mpeg']['audio']['frame_count'] = array_sum($Distribution['bitrate']);
if ($info['mpeg']['audio']['frame_count'] == 0) {
$this->error('no MPEG audio frames found');
return false;
}