public function decodeMPEGaudioHeader($offset, &$info, $recursivesearch = true, $ScanAsCBR = false, $FastMPEGheaderScan = false)
{
static $MPEGaudioVersionLookup;
static $MPEGaudioLayerLookup;
static $MPEGaudioBitrateLookup;
static $MPEGaudioFrequencyLookup;
static $MPEGaudioChannelModeLookup;
static $MPEGaudioModeExtensionLookup;
static $MPEGaudioEmphasisLookup;
if (empty($MPEGaudioVersionLookup)) {
$MPEGaudioVersionLookup = self::MPEGaudioVersionArray();
$MPEGaudioLayerLookup = self::MPEGaudioLayerArray();
$MPEGaudioBitrateLookup = self::MPEGaudioBitrateArray();
$MPEGaudioFrequencyLookup = self::MPEGaudioFrequencyArray();
$MPEGaudioChannelModeLookup = self::MPEGaudioChannelModeArray();
$MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
$MPEGaudioEmphasisLookup = self::MPEGaudioEmphasisArray();
}
if ($this->fseek($offset) != 0) {
$info['error'][] = 'decodeMPEGaudioHeader() failed to seek to next offset at ' . $offset;
return false;
}
//$headerstring = $this->fread(1441); // worst-case max length = 32kHz @ 320kbps layer 3 = 1441 bytes/frame
$headerstring = $this->fread(226);
// LAME header at offset 36 + 190 bytes of Xing/LAME data
// MP3 audio frame structure:
// $aa $aa $aa $aa [$bb $bb] $cc...
// where $aa..$aa is the four-byte mpeg-audio header (below)
// $bb $bb is the optional 2-byte CRC
// and $cc... is the audio data
$head4 = substr($headerstring, 0, 4);
static $MPEGaudioHeaderDecodeCache = array();
if (isset($MPEGaudioHeaderDecodeCache[$head4])) {
$MPEGheaderRawArray = $MPEGaudioHeaderDecodeCache[$head4];
} else {
$MPEGheaderRawArray = self::MPEGaudioHeaderDecode($head4);
$MPEGaudioHeaderDecodeCache[$head4] = $MPEGheaderRawArray;
}
static $MPEGaudioHeaderValidCache = array();
if (!isset($MPEGaudioHeaderValidCache[$head4])) {
// Not in cache
//$MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGheaderRawArray, false, true); // allow badly-formatted freeformat (from LAME 3.90 - 3.93.1)
$MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGheaderRawArray, false, false);
}
// shortcut
if (!isset($info['mpeg']['audio'])) {
$info['mpeg']['audio'] = array();
}
$thisfile_mpeg_audio =& $info['mpeg']['audio'];
if ($MPEGaudioHeaderValidCache[$head4]) {
$thisfile_mpeg_audio['raw'] = $MPEGheaderRawArray;
} else {
$info['error'][] = 'Invalid MPEG audio header (' . getid3_lib::PrintHexBytes($head4) . ') at offset ' . $offset;
return false;
}
if (!$FastMPEGheaderScan) {
$thisfile_mpeg_audio['version'] = $MPEGaudioVersionLookup[$thisfile_mpeg_audio['raw']['version']];
$thisfile_mpeg_audio['layer'] = $MPEGaudioLayerLookup[$thisfile_mpeg_audio['raw']['layer']];
$thisfile_mpeg_audio['channelmode'] = $MPEGaudioChannelModeLookup[$thisfile_mpeg_audio['raw']['channelmode']];
$thisfile_mpeg_audio['channels'] = $thisfile_mpeg_audio['channelmode'] == 'mono' ? 1 : 2;
$thisfile_mpeg_audio['sample_rate'] = $MPEGaudioFrequencyLookup[$thisfile_mpeg_audio['version']][$thisfile_mpeg_audio['raw']['sample_rate']];
$thisfile_mpeg_audio['protection'] = !$thisfile_mpeg_audio['raw']['protection'];
$thisfile_mpeg_audio['private'] = (bool) $thisfile_mpeg_audio['raw']['private'];
$thisfile_mpeg_audio['modeextension'] = $MPEGaudioModeExtensionLookup[$thisfile_mpeg_audio['layer']][$thisfile_mpeg_audio['raw']['modeextension']];
$thisfile_mpeg_audio['copyright'] = (bool) $thisfile_mpeg_audio['raw']['copyright'];
$thisfile_mpeg_audio['original'] = (bool) $thisfile_mpeg_audio['raw']['original'];
$thisfile_mpeg_audio['emphasis'] = $MPEGaudioEmphasisLookup[$thisfile_mpeg_audio['raw']['emphasis']];
$info['audio']['channels'] = $thisfile_mpeg_audio['channels'];
$info['audio']['sample_rate'] = $thisfile_mpeg_audio['sample_rate'];
if ($thisfile_mpeg_audio['protection']) {
$thisfile_mpeg_audio['crc'] = getid3_lib::BigEndian2Int(substr($headerstring, 4, 2));
}
}
if ($thisfile_mpeg_audio['raw']['bitrate'] == 15) {
// http://www.hydrogenaudio.org/?act=ST&f=16&t=9682&st=0
$info['warning'][] = 'Invalid bitrate index (15), this is a known bug in free-format MP3s encoded by LAME v3.90 - 3.93.1';
$thisfile_mpeg_audio['raw']['bitrate'] = 0;
}
$thisfile_mpeg_audio['padding'] = (bool) $thisfile_mpeg_audio['raw']['padding'];
$thisfile_mpeg_audio['bitrate'] = $MPEGaudioBitrateLookup[$thisfile_mpeg_audio['version']][$thisfile_mpeg_audio['layer']][$thisfile_mpeg_audio['raw']['bitrate']];
if ($thisfile_mpeg_audio['bitrate'] == 'free' && $offset == $info['avdataoffset']) {
// only skip multiple frame check if free-format bitstream found at beginning of file
// otherwise is quite possibly simply corrupted data
$recursivesearch = false;
}
// For Layer 2 there are some combinations of bitrate and mode which are not allowed.
if (!$FastMPEGheaderScan && $thisfile_mpeg_audio['layer'] == '2') {
$info['audio']['dataformat'] = 'mp2';
switch ($thisfile_mpeg_audio['channelmode']) {
case 'mono':
if ($thisfile_mpeg_audio['bitrate'] == 'free' || $thisfile_mpeg_audio['bitrate'] <= 192000) {
// these are ok
} else {
$info['error'][] = $thisfile_mpeg_audio['bitrate'] . 'kbps not allowed in Layer 2, ' . $thisfile_mpeg_audio['channelmode'] . '.';
return false;
}
break;
case 'stereo':
case 'joint stereo':
case 'dual channel':
if ($thisfile_mpeg_audio['bitrate'] == 'free' || $thisfile_mpeg_audio['bitrate'] == 64000 || $thisfile_mpeg_audio['bitrate'] >= 96000) {
// these are ok
} else {
$info['error'][] = intval(round($thisfile_mpeg_audio['bitrate'] / 1000)) . 'kbps not allowed in Layer 2, ' . $thisfile_mpeg_audio['channelmode'] . '.';
return false;
}
break;
}
}
if ($info['audio']['sample_rate'] > 0) {
$thisfile_mpeg_audio['framelength'] = self::MPEGaudioFrameLength($thisfile_mpeg_audio['bitrate'], $thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['layer'], (int) $thisfile_mpeg_audio['padding'], $info['audio']['sample_rate']);
}
$nextframetestoffset = $offset + 1;
if ($thisfile_mpeg_audio['bitrate'] != 'free') {
$info['audio']['bitrate'] = $thisfile_mpeg_audio['bitrate'];
if (isset($thisfile_mpeg_audio['framelength'])) {
$nextframetestoffset = $offset + $thisfile_mpeg_audio['framelength'];
} else {
$info['error'][] = 'Frame at offset(' . $offset . ') is has an invalid frame length.';
return false;
}
}
$ExpectedNumberOfAudioBytes = 0;
////////////////////////////////////////////////////////////////////////////////////
// Variable-bitrate headers
if (substr($headerstring, 4 + 32, 4) == 'VBRI') {
// Fraunhofer VBR header is hardcoded 'VBRI' at offset 0x24 (36)
// specs taken from http://minnie.tuhs.org/pipermail/mp3encoder/2001-January/001800.html
$thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
$thisfile_mpeg_audio['VBR_method'] = 'Fraunhofer';
$info['audio']['codec'] = 'Fraunhofer';
$SideInfoData = substr($headerstring, 4 + 2, 32);
$FraunhoferVBROffset = 36;
$thisfile_mpeg_audio['VBR_encoder_version'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 4, 2));
// VbriVersion
$thisfile_mpeg_audio['VBR_encoder_delay'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 6, 2));
// VbriDelay
$thisfile_mpeg_audio['VBR_quality'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 8, 2));
// VbriQuality
$thisfile_mpeg_audio['VBR_bytes'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 10, 4));
// VbriStreamBytes
$thisfile_mpeg_audio['VBR_frames'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 14, 4));
// VbriStreamFrames
$thisfile_mpeg_audio['VBR_seek_offsets'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 18, 2));
// VbriTableSize
$thisfile_mpeg_audio['VBR_seek_scale'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 20, 2));
// VbriTableScale
$thisfile_mpeg_audio['VBR_entry_bytes'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 22, 2));
// VbriEntryBytes
$thisfile_mpeg_audio['VBR_entry_frames'] = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 24, 2));
// VbriEntryFrames
$ExpectedNumberOfAudioBytes = $thisfile_mpeg_audio['VBR_bytes'];
$previousbyteoffset = $offset;
for ($i = 0; $i < $thisfile_mpeg_audio['VBR_seek_offsets']; $i++) {
$Fraunhofer_OffsetN = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset, $thisfile_mpeg_audio['VBR_entry_bytes']));
$FraunhoferVBROffset += $thisfile_mpeg_audio['VBR_entry_bytes'];
$thisfile_mpeg_audio['VBR_offsets_relative'][$i] = $Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale'];
$thisfile_mpeg_audio['VBR_offsets_absolute'][$i] = $Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale'] + $previousbyteoffset;
$previousbyteoffset += $Fraunhofer_OffsetN;
}
} else {
// Xing VBR header is hardcoded 'Xing' at a offset 0x0D (13), 0x15 (21) or 0x24 (36)
// depending on MPEG layer and number of channels
$VBRidOffset = self::XingVBRidOffset($thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['channelmode']);
$SideInfoData = substr($headerstring, 4 + 2, $VBRidOffset - 4);
if (substr($headerstring, $VBRidOffset, strlen('Xing')) == 'Xing' || substr($headerstring, $VBRidOffset, strlen('Info')) == 'Info') {
// 'Xing' is traditional Xing VBR frame
// 'Info' is LAME-encoded CBR (This was done to avoid CBR files to be recognized as traditional Xing VBR files by some decoders.)
// 'Info' *can* legally be used to specify a VBR file as well, however.
// http://www.multiweb.cz/twoinches/MP3inside.htm
//00..03 = "Xing" or "Info"
//04..07 = Flags:
// 0x01 Frames Flag set if value for number of frames in file is stored
// 0x02 Bytes Flag set if value for filesize in bytes is stored
// 0x04 TOC Flag set if values for TOC are stored
// 0x08 VBR Scale Flag set if values for VBR scale is stored
//08..11 Frames: Number of frames in file (including the first Xing/Info one)
//12..15 Bytes: File length in Bytes
//16..115 TOC (Table of Contents):
// Contains of 100 indexes (one Byte length) for easier lookup in file. Approximately solves problem with moving inside file.
// Each Byte has a value according this formula:
// (TOC[i] / 256) * fileLenInBytes
// So if song lasts eg. 240 sec. and you want to jump to 60. sec. (and file is 5 000 000 Bytes length) you can use:
// TOC[(60/240)*100] = TOC[25]
// and corresponding Byte in file is then approximately at:
// (TOC[25]/256) * 5000000
//116..119 VBR Scale
// should be safe to leave this at 'vbr' and let it be overriden to 'cbr' if a CBR preset/mode is used by LAME
// if (substr($headerstring, $VBRidOffset, strlen('Info')) == 'Xing') {
$thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
$thisfile_mpeg_audio['VBR_method'] = 'Xing';
// } else {
// $ScanAsCBR = true;
// $thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
// }
$thisfile_mpeg_audio['xing_flags_raw'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 4, 4));
$thisfile_mpeg_audio['xing_flags']['frames'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x1);
$thisfile_mpeg_audio['xing_flags']['bytes'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x2);
$thisfile_mpeg_audio['xing_flags']['toc'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x4);
$thisfile_mpeg_audio['xing_flags']['vbr_scale'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x8);
if ($thisfile_mpeg_audio['xing_flags']['frames']) {
$thisfile_mpeg_audio['VBR_frames'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 8, 4));
//$thisfile_mpeg_audio['VBR_frames']--; // don't count header Xing/Info frame
}
if ($thisfile_mpeg_audio['xing_flags']['bytes']) {
$thisfile_mpeg_audio['VBR_bytes'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 12, 4));
}
//if (($thisfile_mpeg_audio['bitrate'] == 'free') && !empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {
if (!empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {
$framelengthfloat = $thisfile_mpeg_audio['VBR_bytes'] / $thisfile_mpeg_audio['VBR_frames'];
if ($thisfile_mpeg_audio['layer'] == '1') {
// BitRate = (((FrameLengthInBytes / 4) - Padding) * SampleRate) / 12
//$info['audio']['bitrate'] = ((($framelengthfloat / 4) - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 12;
$info['audio']['bitrate'] = $framelengthfloat / 4 * $thisfile_mpeg_audio['sample_rate'] * (2 / $info['audio']['channels']) / 12;
} else {
// Bitrate = ((FrameLengthInBytes - Padding) * SampleRate) / 144
//$info['audio']['bitrate'] = (($framelengthfloat - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 144;
$info['audio']['bitrate'] = $framelengthfloat * $thisfile_mpeg_audio['sample_rate'] * (2 / $info['audio']['channels']) / 144;
}
$thisfile_mpeg_audio['framelength'] = floor($framelengthfloat);
}
if ($thisfile_mpeg_audio['xing_flags']['toc']) {
$LAMEtocData = substr($headerstring, $VBRidOffset + 16, 100);
for ($i = 0; $i < 100; $i++) {
$thisfile_mpeg_audio['toc'][$i] = ord($LAMEtocData[$i]);
}
}
if ($thisfile_mpeg_audio['xing_flags']['vbr_scale']) {
$thisfile_mpeg_audio['VBR_scale'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 116, 4));
}
// http://gabriel.mp3-tech.org/mp3infotag.html
if (substr($headerstring, $VBRidOffset + 120, 4) == 'LAME') {
// shortcut
$thisfile_mpeg_audio['LAME'] = array();
$thisfile_mpeg_audio_lame =& $thisfile_mpeg_audio['LAME'];
$thisfile_mpeg_audio_lame['long_version'] = substr($headerstring, $VBRidOffset + 120, 20);
$thisfile_mpeg_audio_lame['short_version'] = substr($thisfile_mpeg_audio_lame['long_version'], 0, 9);
if ($thisfile_mpeg_audio_lame['short_version'] >= 'LAME3.90') {
// extra 11 chars are not part of version string when LAMEtag present
unset($thisfile_mpeg_audio_lame['long_version']);
// It the LAME tag was only introduced in LAME v3.90
// http://www.hydrogenaudio.org/?act=ST&f=15&t=9933
// Offsets of various bytes in http://gabriel.mp3-tech.org/mp3infotag.html
// are assuming a 'Xing' identifier offset of 0x24, which is the case for
// MPEG-1 non-mono, but not for other combinations
$LAMEtagOffsetContant = $VBRidOffset - 0x24;
// shortcuts
$thisfile_mpeg_audio_lame['RGAD'] = array('track' => array(), 'album' => array());
$thisfile_mpeg_audio_lame_RGAD =& $thisfile_mpeg_audio_lame['RGAD'];
$thisfile_mpeg_audio_lame_RGAD_track =& $thisfile_mpeg_audio_lame_RGAD['track'];
$thisfile_mpeg_audio_lame_RGAD_album =& $thisfile_mpeg_audio_lame_RGAD['album'];
$thisfile_mpeg_audio_lame['raw'] = array();
$thisfile_mpeg_audio_lame_raw =& $thisfile_mpeg_audio_lame['raw'];
// byte $9B VBR Quality
// This field is there to indicate a quality level, although the scale was not precised in the original Xing specifications.
// Actually overwrites original Xing bytes
unset($thisfile_mpeg_audio['VBR_scale']);
$thisfile_mpeg_audio_lame['vbr_quality'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0x9b, 1));
// bytes $9C-$A4 Encoder short VersionString
$thisfile_mpeg_audio_lame['short_version'] = substr($headerstring, $LAMEtagOffsetContant + 0x9c, 9);
// byte $A5 Info Tag revision + VBR method
$LAMEtagRevisionVBRmethod = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xa5, 1));
$thisfile_mpeg_audio_lame['tag_revision'] = ($LAMEtagRevisionVBRmethod & 0xf0) >> 4;
$thisfile_mpeg_audio_lame_raw['vbr_method'] = $LAMEtagRevisionVBRmethod & 0xf;
$thisfile_mpeg_audio_lame['vbr_method'] = self::LAMEvbrMethodLookup($thisfile_mpeg_audio_lame_raw['vbr_method']);
$thisfile_mpeg_audio['bitrate_mode'] = substr($thisfile_mpeg_audio_lame['vbr_method'], 0, 3);
// usually either 'cbr' or 'vbr', but truncates 'vbr-old / vbr-rh' to 'vbr'
// byte $A6 Lowpass filter value
$thisfile_mpeg_audio_lame['lowpass_frequency'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xa6, 1)) * 100;
// bytes $A7-$AE Replay Gain
// http://privatewww.essex.ac.uk/~djmrob/replaygain/rg_data_format.html
// bytes $A7-$AA : 32 bit floating point "Peak signal amplitude"
if ($thisfile_mpeg_audio_lame['short_version'] >= 'LAME3.94b') {
// LAME 3.94a16 and later - 9.23 fixed point
// ie 0x0059E2EE / (2^23) = 5890798 / 8388608 = 0.7022378444671630859375
$thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] = (double) (getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xa7, 4)) / 8388608);
} else {
// LAME 3.94a15 and earlier - 32-bit floating point
// Actually 3.94a16 will fall in here too and be WRONG, but is hard to detect 3.94a16 vs 3.94a15
$thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] = getid3_lib::LittleEndian2Float(substr($headerstring, $LAMEtagOffsetContant + 0xa7, 4));
}
if ($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] == 0) {
unset($thisfile_mpeg_audio_lame_RGAD['peak_amplitude']);
} else {
$thisfile_mpeg_audio_lame_RGAD['peak_db'] = getid3_lib::RGADamplitude2dB($thisfile_mpeg_audio_lame_RGAD['peak_amplitude']);
}
$thisfile_mpeg_audio_lame_raw['RGAD_track'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xab, 2));
$thisfile_mpeg_audio_lame_raw['RGAD_album'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xad, 2));
if ($thisfile_mpeg_audio_lame_raw['RGAD_track'] != 0) {
$thisfile_mpeg_audio_lame_RGAD_track['raw']['name'] = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0xe000) >> 13;
$thisfile_mpeg_audio_lame_RGAD_track['raw']['originator'] = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x1c00) >> 10;
$thisfile_mpeg_audio_lame_RGAD_track['raw']['sign_bit'] = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x200) >> 9;
$thisfile_mpeg_audio_lame_RGAD_track['raw']['gain_adjust'] = $thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x1ff;
$thisfile_mpeg_audio_lame_RGAD_track['name'] = getid3_lib::RGADnameLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['name']);
$thisfile_mpeg_audio_lame_RGAD_track['originator'] = getid3_lib::RGADoriginatorLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['originator']);
$thisfile_mpeg_audio_lame_RGAD_track['gain_db'] = getid3_lib::RGADadjustmentLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['gain_adjust'], $thisfile_mpeg_audio_lame_RGAD_track['raw']['sign_bit']);
if (!empty($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'])) {
$info['replay_gain']['track']['peak'] = $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'];
}
$info['replay_gain']['track']['originator'] = $thisfile_mpeg_audio_lame_RGAD_track['originator'];
$info['replay_gain']['track']['adjustment'] = $thisfile_mpeg_audio_lame_RGAD_track['gain_db'];
} else {
unset($thisfile_mpeg_audio_lame_RGAD['track']);
}
if ($thisfile_mpeg_audio_lame_raw['RGAD_album'] != 0) {
$thisfile_mpeg_audio_lame_RGAD_album['raw']['name'] = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0xe000) >> 13;
$thisfile_mpeg_audio_lame_RGAD_album['raw']['originator'] = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x1c00) >> 10;
$thisfile_mpeg_audio_lame_RGAD_album['raw']['sign_bit'] = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x200) >> 9;
$thisfile_mpeg_audio_lame_RGAD_album['raw']['gain_adjust'] = $thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x1ff;
$thisfile_mpeg_audio_lame_RGAD_album['name'] = getid3_lib::RGADnameLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['name']);
$thisfile_mpeg_audio_lame_RGAD_album['originator'] = getid3_lib::RGADoriginatorLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['originator']);
$thisfile_mpeg_audio_lame_RGAD_album['gain_db'] = getid3_lib::RGADadjustmentLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['gain_adjust'], $thisfile_mpeg_audio_lame_RGAD_album['raw']['sign_bit']);
if (!empty($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'])) {
$info['replay_gain']['album']['peak'] = $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'];
}
$info['replay_gain']['album']['originator'] = $thisfile_mpeg_audio_lame_RGAD_album['originator'];
$info['replay_gain']['album']['adjustment'] = $thisfile_mpeg_audio_lame_RGAD_album['gain_db'];
} else {
unset($thisfile_mpeg_audio_lame_RGAD['album']);
}
if (empty($thisfile_mpeg_audio_lame_RGAD)) {
unset($thisfile_mpeg_audio_lame['RGAD']);
}
// byte $AF Encoding flags + ATH Type
$EncodingFlagsATHtype = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xaf, 1));
$thisfile_mpeg_audio_lame['encoding_flags']['nspsytune'] = (bool) ($EncodingFlagsATHtype & 0x10);
$thisfile_mpeg_audio_lame['encoding_flags']['nssafejoint'] = (bool) ($EncodingFlagsATHtype & 0x20);
$thisfile_mpeg_audio_lame['encoding_flags']['nogap_next'] = (bool) ($EncodingFlagsATHtype & 0x40);
$thisfile_mpeg_audio_lame['encoding_flags']['nogap_prev'] = (bool) ($EncodingFlagsATHtype & 0x80);
$thisfile_mpeg_audio_lame['ath_type'] = $EncodingFlagsATHtype & 0xf;
// byte $B0 if ABR {specified bitrate} else {minimal bitrate}
$thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb0, 1));
if ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 2) {
// Average BitRate (ABR)
$thisfile_mpeg_audio_lame['bitrate_abr'] = $thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'];
} elseif ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 1) {
// Constant BitRate (CBR)
// ignore
} elseif ($thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'] > 0) {
// Variable BitRate (VBR) - minimum bitrate
$thisfile_mpeg_audio_lame['bitrate_min'] = $thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'];
}
// bytes $B1-$B3 Encoder delays
$EncoderDelays = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb1, 3));
$thisfile_mpeg_audio_lame['encoder_delay'] = ($EncoderDelays & 0xfff000) >> 12;
$thisfile_mpeg_audio_lame['end_padding'] = $EncoderDelays & 0xfff;
// byte $B4 Misc
$MiscByte = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb4, 1));
$thisfile_mpeg_audio_lame_raw['noise_shaping'] = $MiscByte & 0x3;
$thisfile_mpeg_audio_lame_raw['stereo_mode'] = ($MiscByte & 0x1c) >> 2;
$thisfile_mpeg_audio_lame_raw['not_optimal_quality'] = ($MiscByte & 0x20) >> 5;
$thisfile_mpeg_audio_lame_raw['source_sample_freq'] = ($MiscByte & 0xc0) >> 6;
$thisfile_mpeg_audio_lame['noise_shaping'] = $thisfile_mpeg_audio_lame_raw['noise_shaping'];
$thisfile_mpeg_audio_lame['stereo_mode'] = self::LAMEmiscStereoModeLookup($thisfile_mpeg_audio_lame_raw['stereo_mode']);
$thisfile_mpeg_audio_lame['not_optimal_quality'] = (bool) $thisfile_mpeg_audio_lame_raw['not_optimal_quality'];
$thisfile_mpeg_audio_lame['source_sample_freq'] = self::LAMEmiscSourceSampleFrequencyLookup($thisfile_mpeg_audio_lame_raw['source_sample_freq']);
// byte $B5 MP3 Gain
$thisfile_mpeg_audio_lame_raw['mp3_gain'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb5, 1), false, true);
$thisfile_mpeg_audio_lame['mp3_gain_db'] = getid3_lib::RGADamplitude2dB(2) / 4 * $thisfile_mpeg_audio_lame_raw['mp3_gain'];
$thisfile_mpeg_audio_lame['mp3_gain_factor'] = pow(2, $thisfile_mpeg_audio_lame['mp3_gain_db'] / 6);
// bytes $B6-$B7 Preset and surround info
$PresetSurroundBytes = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb6, 2));
// Reserved = ($PresetSurroundBytes & 0xC000);
$thisfile_mpeg_audio_lame_raw['surround_info'] = $PresetSurroundBytes & 0x3800;
$thisfile_mpeg_audio_lame['surround_info'] = self::LAMEsurroundInfoLookup($thisfile_mpeg_audio_lame_raw['surround_info']);
$thisfile_mpeg_audio_lame['preset_used_id'] = $PresetSurroundBytes & 0x7ff;
$thisfile_mpeg_audio_lame['preset_used'] = self::LAMEpresetUsedLookup($thisfile_mpeg_audio_lame);
if (!empty($thisfile_mpeg_audio_lame['preset_used_id']) && empty($thisfile_mpeg_audio_lame['preset_used'])) {
$info['warning'][] = 'Unknown LAME preset used (' . $thisfile_mpeg_audio_lame['preset_used_id'] . ') - please report to info@getid3.org';
}
if ($thisfile_mpeg_audio_lame['short_version'] == 'LAME3.90.' && !empty($thisfile_mpeg_audio_lame['preset_used_id'])) {
// this may change if 3.90.4 ever comes out
$thisfile_mpeg_audio_lame['short_version'] = 'LAME3.90.3';
}
// bytes $B8-$BB MusicLength
$thisfile_mpeg_audio_lame['audio_bytes'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xb8, 4));
$ExpectedNumberOfAudioBytes = $thisfile_mpeg_audio_lame['audio_bytes'] > 0 ? $thisfile_mpeg_audio_lame['audio_bytes'] : $thisfile_mpeg_audio['VBR_bytes'];
// bytes $BC-$BD MusicCRC
$thisfile_mpeg_audio_lame['music_crc'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xbc, 2));
// bytes $BE-$BF CRC-16 of Info Tag
$thisfile_mpeg_audio_lame['lame_tag_crc'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xbe, 2));
// LAME CBR
if ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 1) {
$thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
$thisfile_mpeg_audio['bitrate'] = self::ClosestStandardMP3Bitrate($thisfile_mpeg_audio['bitrate']);
$info['audio']['bitrate'] = $thisfile_mpeg_audio['bitrate'];
//if (empty($thisfile_mpeg_audio['bitrate']) || (!empty($thisfile_mpeg_audio_lame['bitrate_min']) && ($thisfile_mpeg_audio_lame['bitrate_min'] != 255))) {
// $thisfile_mpeg_audio['bitrate'] = $thisfile_mpeg_audio_lame['bitrate_min'];
//}
}
}
}
} else {
// not Fraunhofer or Xing VBR methods, most likely CBR (but could be VBR with no header)
$thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
if ($recursivesearch) {
$thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
if ($this->RecursiveFrameScanning($offset, $nextframetestoffset, true)) {
$recursivesearch = false;
$thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
}
if ($thisfile_mpeg_audio['bitrate_mode'] == 'vbr') {
$info['warning'][] = 'VBR file with no VBR header. Bitrate values calculated from actual frame bitrates.';
}
}
}
}
if ($ExpectedNumberOfAudioBytes > 0 && $ExpectedNumberOfAudioBytes != $info['avdataend'] - $info['avdataoffset']) {
if ($ExpectedNumberOfAudioBytes > $info['avdataend'] - $info['avdataoffset']) {
if ($this->isDependencyFor('matroska') || $this->isDependencyFor('riff')) {
// ignore, audio data is broken into chunks so will always be data "missing"
} elseif ($ExpectedNumberOfAudioBytes - ($info['avdataend'] - $info['avdataoffset']) == 1) {
$this->warning('Last byte of data truncated (this is a known bug in Meracl ID3 Tag Writer before v1.3.5)');
} else {
$this->warning('Probable truncated file: expecting ' . $ExpectedNumberOfAudioBytes . ' bytes of audio data, only found ' . ($info['avdataend'] - $info['avdataoffset']) . ' (short by ' . ($ExpectedNumberOfAudioBytes - ($info['avdataend'] - $info['avdataoffset'])) . ' bytes)');
}
} else {
if ($info['avdataend'] - $info['avdataoffset'] - $ExpectedNumberOfAudioBytes == 1) {
// $prenullbytefileoffset = $this->ftell();
// $this->fseek($info['avdataend']);
// $PossibleNullByte = $this->fread(1);
// $this->fseek($prenullbytefileoffset);
// if ($PossibleNullByte === "\x00") {
$info['avdataend']--;
// $info['warning'][] = 'Extra null byte at end of MP3 data assumed to be RIFF padding and therefore ignored';
// } else {
// $info['warning'][] = 'Too much data in file: expecting '.$ExpectedNumberOfAudioBytes.' bytes of audio data, found '.($info['avdataend'] - $info['avdataoffset']).' ('.(($info['avdataend'] - $info['avdataoffset']) - $ExpectedNumberOfAudioBytes).' bytes too many)';
// }
} else {
$info['warning'][] = 'Too much data in file: expecting ' . $ExpectedNumberOfAudioBytes . ' bytes of audio data, found ' . ($info['avdataend'] - $info['avdataoffset']) . ' (' . ($info['avdataend'] - $info['avdataoffset'] - $ExpectedNumberOfAudioBytes) . ' bytes too many)';
}
}
}
if ($thisfile_mpeg_audio['bitrate'] == 'free' && empty($info['audio']['bitrate'])) {
if ($offset == $info['avdataoffset'] && empty($thisfile_mpeg_audio['VBR_frames'])) {
$framebytelength = $this->FreeFormatFrameLength($offset, true);
if ($framebytelength > 0) {
$thisfile_mpeg_audio['framelength'] = $framebytelength;
if ($thisfile_mpeg_audio['layer'] == '1') {
// BitRate = (((FrameLengthInBytes / 4) - Padding) * SampleRate) / 12
$info['audio']['bitrate'] = ($framebytelength / 4 - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate'] / 12;
} else {
// Bitrate = ((FrameLengthInBytes - Padding) * SampleRate) / 144
$info['audio']['bitrate'] = ($framebytelength - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate'] / 144;
}
} else {
$info['error'][] = 'Error calculating frame length of free-format MP3 without Xing/LAME header';
}
}
}
if (isset($thisfile_mpeg_audio['VBR_frames']) ? $thisfile_mpeg_audio['VBR_frames'] : '') {
switch ($thisfile_mpeg_audio['bitrate_mode']) {
case 'vbr':
case 'abr':
$bytes_per_frame = 1152;
if ($thisfile_mpeg_audio['version'] == '1' && $thisfile_mpeg_audio['layer'] == 1) {
$bytes_per_frame = 384;
} elseif (($thisfile_mpeg_audio['version'] == '2' || $thisfile_mpeg_audio['version'] == '2.5') && $thisfile_mpeg_audio['layer'] == 3) {
$bytes_per_frame = 576;
}
$thisfile_mpeg_audio['VBR_bitrate'] = isset($thisfile_mpeg_audio['VBR_bytes']) ? $thisfile_mpeg_audio['VBR_bytes'] / $thisfile_mpeg_audio['VBR_frames'] * 8 * ($info['audio']['sample_rate'] / $bytes_per_frame) : 0;
if ($thisfile_mpeg_audio['VBR_bitrate'] > 0) {
$info['audio']['bitrate'] = $thisfile_mpeg_audio['VBR_bitrate'];
$thisfile_mpeg_audio['bitrate'] = $thisfile_mpeg_audio['VBR_bitrate'];
// to avoid confusion
}
break;
}
}
// End variable-bitrate headers
////////////////////////////////////////////////////////////////////////////////////
if ($recursivesearch) {
if (!$this->RecursiveFrameScanning($offset, $nextframetestoffset, $ScanAsCBR)) {
return false;
}
}
//if (false) {
// // experimental side info parsing section - not returning anything useful yet
//
// $SideInfoBitstream = getid3_lib::BigEndian2Bin($SideInfoData);
// $SideInfoOffset = 0;
//
// if ($thisfile_mpeg_audio['version'] == '1') {
// if ($thisfile_mpeg_audio['channelmode'] == 'mono') {
// // MPEG-1 (mono)
// $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 9);
// $SideInfoOffset += 9;
// $SideInfoOffset += 5;
// } else {
// // MPEG-1 (stereo, joint-stereo, dual-channel)
// $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 9);
// $SideInfoOffset += 9;
// $SideInfoOffset += 3;
// }
// } else { // 2 or 2.5
// if ($thisfile_mpeg_audio['channelmode'] == 'mono') {
// // MPEG-2, MPEG-2.5 (mono)
// $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 8);
// $SideInfoOffset += 8;
// $SideInfoOffset += 1;
// } else {
// // MPEG-2, MPEG-2.5 (stereo, joint-stereo, dual-channel)
// $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 8);
// $SideInfoOffset += 8;
// $SideInfoOffset += 2;
// }
// }
//
// if ($thisfile_mpeg_audio['version'] == '1') {
// for ($channel = 0; $channel < $info['audio']['channels']; $channel++) {
// for ($scfsi_band = 0; $scfsi_band < 4; $scfsi_band++) {
// $thisfile_mpeg_audio['scfsi'][$channel][$scfsi_band] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 2;
// }
// }
// }
// for ($granule = 0; $granule < (($thisfile_mpeg_audio['version'] == '1') ? 2 : 1); $granule++) {
// for ($channel = 0; $channel < $info['audio']['channels']; $channel++) {
// $thisfile_mpeg_audio['part2_3_length'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 12);
// $SideInfoOffset += 12;
// $thisfile_mpeg_audio['big_values'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 9);
// $SideInfoOffset += 9;
// $thisfile_mpeg_audio['global_gain'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 8);
// $SideInfoOffset += 8;
// if ($thisfile_mpeg_audio['version'] == '1') {
// $thisfile_mpeg_audio['scalefac_compress'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 4);
// $SideInfoOffset += 4;
// } else {
// $thisfile_mpeg_audio['scalefac_compress'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 9);
// $SideInfoOffset += 9;
// }
// $thisfile_mpeg_audio['window_switching_flag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 1;
//
// if ($thisfile_mpeg_audio['window_switching_flag'][$granule][$channel] == '1') {
//
// $thisfile_mpeg_audio['block_type'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 2);
// $SideInfoOffset += 2;
// $thisfile_mpeg_audio['mixed_block_flag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 1;
//
// for ($region = 0; $region < 2; $region++) {
// $thisfile_mpeg_audio['table_select'][$granule][$channel][$region] = substr($SideInfoBitstream, $SideInfoOffset, 5);
// $SideInfoOffset += 5;
// }
// $thisfile_mpeg_audio['table_select'][$granule][$channel][2] = 0;
//
// for ($window = 0; $window < 3; $window++) {
// $thisfile_mpeg_audio['subblock_gain'][$granule][$channel][$window] = substr($SideInfoBitstream, $SideInfoOffset, 3);
// $SideInfoOffset += 3;
// }
//
// } else {
//
// for ($region = 0; $region < 3; $region++) {
// $thisfile_mpeg_audio['table_select'][$granule][$channel][$region] = substr($SideInfoBitstream, $SideInfoOffset, 5);
// $SideInfoOffset += 5;
// }
//
// $thisfile_mpeg_audio['region0_count'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 4);
// $SideInfoOffset += 4;
// $thisfile_mpeg_audio['region1_count'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 3);
// $SideInfoOffset += 3;
// $thisfile_mpeg_audio['block_type'][$granule][$channel] = 0;
// }
//
// if ($thisfile_mpeg_audio['version'] == '1') {
// $thisfile_mpeg_audio['preflag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 1;
// }
// $thisfile_mpeg_audio['scalefac_scale'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 1;
// $thisfile_mpeg_audio['count1table_select'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
// $SideInfoOffset += 1;
// }
// }
//}
return true;
}
function CalculateReplayGain()
{
if (isset($this->info['replay_gain'])) {
$this->info['replay_gain']['reference_volume'] = 89;
if (isset($this->info['replay_gain']['track']['adjustment'])) {
$this->info['replay_gain']['track']['volume'] = $this->info['replay_gain']['reference_volume'] - $this->info['replay_gain']['track']['adjustment'];
}
if (isset($this->info['replay_gain']['album']['adjustment'])) {
$this->info['replay_gain']['album']['volume'] = $this->info['replay_gain']['reference_volume'] - $this->info['replay_gain']['album']['adjustment'];
}
if (isset($this->info['replay_gain']['track']['peak'])) {
$this->info['replay_gain']['track']['max_noclip_gain'] = 0 - getid3_lib::RGADamplitude2dB($this->info['replay_gain']['track']['peak']);
}
if (isset($this->info['replay_gain']['album']['peak'])) {
$this->info['replay_gain']['album']['max_noclip_gain'] = 0 - getid3_lib::RGADamplitude2dB($this->info['replay_gain']['album']['peak']);
}
}
return true;
}
public static function heavyCompression($compre)
{
// The first four bits indicate gain changes in 6.02dB increments which can be
// implemented with an arithmetic shift operation. The following four bits
// indicate linear gain changes, and require a 5-bit multiply.
// We will represent the two 4-bit fields of compr as follows:
// X0 X1 X2 X3 . Y4 Y5 Y6 Y7
// The meaning of the X values is most simply described by considering X to represent a 4-bit
// signed integer with values from -8 to +7. The gain indicated by X is then (X + 1) * 6.02 dB. The
// following table shows this in detail.
// Meaning of 4 msb of compr
// 7 +48.16 dB
// 6 +42.14 dB
// 5 +36.12 dB
// 4 +30.10 dB
// 3 +24.08 dB
// 2 +18.06 dB
// 1 +12.04 dB
// 0 +6.02 dB
// -1 0 dB
// -2 -6.02 dB
// -3 -12.04 dB
// -4 -18.06 dB
// -5 -24.08 dB
// -6 -30.10 dB
// -7 -36.12 dB
// -8 -42.14 dB
$fourbit = str_pad(decbin(($compre & 0xf0) >> 4), 4, '0', STR_PAD_LEFT);
if ($fourbit[0] == '1') {
$log_gain = -8 + bindec(substr($fourbit, 1));
} else {
$log_gain = bindec(substr($fourbit, 1));
}
$log_gain = ($log_gain + 1) * getid3_lib::RGADamplitude2dB(2);
// The value of Y is a linear representation of a gain change of up to -6 dB. Y is considered to
// be an unsigned fractional integer, with a leading value of 1, or: 0.1 Y4 Y5 Y6 Y7 (base 2). Y can
// represent values between 0.111112 (or 31/32) and 0.100002 (or 1/2). Thus, Y can represent gain
// changes from -0.28 dB to -6.02 dB.
$lin_gain = (16 + ($compre & 0xf)) / 32;
// The combination of X and Y values allows compr to indicate gain changes from
// 48.16 - 0.28 = +47.89 dB, to
// -42.14 - 6.02 = -48.16 dB.
return $log_gain - $lin_gain;
}
