public function getAACADIFheaderFilepointer()
{
$info =& $this->getid3->info;
$info['fileformat'] = 'aac';
$info['audio']['dataformat'] = 'aac';
$info['audio']['lossless'] = false;
$this->fseek($info['avdataoffset']);
$AACheader = $this->fread(1024);
$offset = 0;
if (substr($AACheader, 0, 4) == 'ADIF') {
// http://faac.sourceforge.net/wiki/index.php?page=ADIF
// http://libmpeg.org/mpeg4/doc/w2203tfs.pdf
// adif_header() {
// adif_id 32
// copyright_id_present 1
// if( copyright_id_present )
// copyright_id 72
// original_copy 1
// home 1
// bitstream_type 1
// bitrate 23
// num_program_config_elements 4
// for (i = 0; i < num_program_config_elements + 1; i++ ) {
// if( bitstream_type == '0' )
// adif_buffer_fullness 20
// program_config_element()
// }
// }
$AACheaderBitstream = Utils::BigEndian2Bin($AACheader);
$bitoffset = 0;
$info['aac']['header_type'] = 'ADIF';
$bitoffset += 32;
$info['aac']['header']['mpeg_version'] = 4;
$info['aac']['header']['copyright'] = (bool) (substr($AACheaderBitstream, $bitoffset, 1) == '1');
$bitoffset += 1;
if ($info['aac']['header']['copyright']) {
$info['aac']['header']['copyright_id'] = Utils::Bin2String(substr($AACheaderBitstream, $bitoffset, 72));
$bitoffset += 72;
}
$info['aac']['header']['original_copy'] = (bool) (substr($AACheaderBitstream, $bitoffset, 1) == '1');
$bitoffset += 1;
$info['aac']['header']['home'] = (bool) (substr($AACheaderBitstream, $bitoffset, 1) == '1');
$bitoffset += 1;
$info['aac']['header']['is_vbr'] = (bool) (substr($AACheaderBitstream, $bitoffset, 1) == '1');
$bitoffset += 1;
if ($info['aac']['header']['is_vbr']) {
$info['audio']['bitrate_mode'] = 'vbr';
$info['aac']['header']['bitrate_max'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 23));
$bitoffset += 23;
} else {
$info['audio']['bitrate_mode'] = 'cbr';
$info['aac']['header']['bitrate'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 23));
$bitoffset += 23;
$info['audio']['bitrate'] = $info['aac']['header']['bitrate'];
}
if ($info['audio']['bitrate'] == 0) {
$info['error'][] = 'Corrupt AAC file: bitrate_audio == zero';
return false;
}
$info['aac']['header']['num_program_configs'] = 1 + Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
for ($i = 0; $i < $info['aac']['header']['num_program_configs']; $i++) {
// http://www.audiocoding.com/wiki/index.php?page=program_config_element
// buffer_fullness 20
// element_instance_tag 4
// object_type 2
// sampling_frequency_index 4
// num_front_channel_elements 4
// num_side_channel_elements 4
// num_back_channel_elements 4
// num_lfe_channel_elements 2
// num_assoc_data_elements 3
// num_valid_cc_elements 4
// mono_mixdown_present 1
// mono_mixdown_element_number 4 if mono_mixdown_present == 1
// stereo_mixdown_present 1
// stereo_mixdown_element_number 4 if stereo_mixdown_present == 1
// matrix_mixdown_idx_present 1
// matrix_mixdown_idx 2 if matrix_mixdown_idx_present == 1
// pseudo_surround_enable 1 if matrix_mixdown_idx_present == 1
// for (i = 0; i < num_front_channel_elements; i++) {
// front_element_is_cpe[i] 1
// front_element_tag_select[i] 4
// }
// for (i = 0; i < num_side_channel_elements; i++) {
// side_element_is_cpe[i] 1
// side_element_tag_select[i] 4
// }
// for (i = 0; i < num_back_channel_elements; i++) {
// back_element_is_cpe[i] 1
// back_element_tag_select[i] 4
// }
// for (i = 0; i < num_lfe_channel_elements; i++) {
// lfe_element_tag_select[i] 4
// }
// for (i = 0; i < num_assoc_data_elements; i++) {
// assoc_data_element_tag_select[i] 4
// }
// for (i = 0; i < num_valid_cc_elements; i++) {
// cc_element_is_ind_sw[i] 1
// valid_cc_element_tag_select[i] 4
// }
// byte_alignment() VAR
// comment_field_bytes 8
// for (i = 0; i < comment_field_bytes; i++) {
// comment_field_data[i] 8
// }
if (!$info['aac']['header']['is_vbr']) {
$info['aac']['program_configs'][$i]['buffer_fullness'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 20));
$bitoffset += 20;
}
$info['aac']['program_configs'][$i]['element_instance_tag'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['object_type'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 2));
$bitoffset += 2;
$info['aac']['program_configs'][$i]['sampling_frequency_index'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['num_front_channel_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['num_side_channel_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['num_back_channel_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['num_lfe_channel_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 2));
$bitoffset += 2;
$info['aac']['program_configs'][$i]['num_assoc_data_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 3));
$bitoffset += 3;
$info['aac']['program_configs'][$i]['num_valid_cc_elements'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
$info['aac']['program_configs'][$i]['mono_mixdown_present'] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
if ($info['aac']['program_configs'][$i]['mono_mixdown_present']) {
$info['aac']['program_configs'][$i]['mono_mixdown_element_number'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
$info['aac']['program_configs'][$i]['stereo_mixdown_present'] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
if ($info['aac']['program_configs'][$i]['stereo_mixdown_present']) {
$info['aac']['program_configs'][$i]['stereo_mixdown_element_number'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
$info['aac']['program_configs'][$i]['matrix_mixdown_idx_present'] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
if ($info['aac']['program_configs'][$i]['matrix_mixdown_idx_present']) {
$info['aac']['program_configs'][$i]['matrix_mixdown_idx'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 2));
$bitoffset += 2;
$info['aac']['program_configs'][$i]['pseudo_surround_enable'] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_front_channel_elements']; $j++) {
$info['aac']['program_configs'][$i]['front_element_is_cpe'][$j] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
$info['aac']['program_configs'][$i]['front_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_side_channel_elements']; $j++) {
$info['aac']['program_configs'][$i]['side_element_is_cpe'][$j] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
$info['aac']['program_configs'][$i]['side_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_back_channel_elements']; $j++) {
$info['aac']['program_configs'][$i]['back_element_is_cpe'][$j] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
$info['aac']['program_configs'][$i]['back_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_lfe_channel_elements']; $j++) {
$info['aac']['program_configs'][$i]['lfe_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_assoc_data_elements']; $j++) {
$info['aac']['program_configs'][$i]['assoc_data_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
for ($j = 0; $j < $info['aac']['program_configs'][$i]['num_valid_cc_elements']; $j++) {
$info['aac']['program_configs'][$i]['cc_element_is_ind_sw'][$j] = (bool) Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 1));
$bitoffset += 1;
$info['aac']['program_configs'][$i]['valid_cc_element_tag_select'][$j] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 4));
$bitoffset += 4;
}
$bitoffset = ceil($bitoffset / 8) * 8;
$info['aac']['program_configs'][$i]['comment_field_bytes'] = Utils::Bin2Dec(substr($AACheaderBitstream, $bitoffset, 8));
$bitoffset += 8;
$info['aac']['program_configs'][$i]['comment_field'] = Utils::Bin2String(substr($AACheaderBitstream, $bitoffset, 8 * $info['aac']['program_configs'][$i]['comment_field_bytes']));
$bitoffset += 8 * $info['aac']['program_configs'][$i]['comment_field_bytes'];
$info['aac']['header']['profile'] = self::AACprofileLookup($info['aac']['program_configs'][$i]['object_type'], $info['aac']['header']['mpeg_version']);
$info['aac']['program_configs'][$i]['sampling_frequency'] = self::AACsampleRateLookup($info['aac']['program_configs'][$i]['sampling_frequency_index']);
$info['audio']['sample_rate'] = $info['aac']['program_configs'][$i]['sampling_frequency'];
$info['audio']['channels'] = self::AACchannelCountCalculate($info['aac']['program_configs'][$i]);
if ($info['aac']['program_configs'][$i]['comment_field']) {
$info['aac']['comments'][] = $info['aac']['program_configs'][$i]['comment_field'];
}
}
$info['playtime_seconds'] = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['audio']['bitrate'];
$info['audio']['encoder_options'] = $info['aac']['header_type'] . ' ' . $info['aac']['header']['profile'];
return true;
} else {
unset($info['fileformat']);
unset($info['aac']);
$info['error'][] = 'AAC-ADIF synch not found at offset ' . $info['avdataoffset'] . ' (expected "ADIF", found "' . substr($AACheader, 0, 4) . '" instead)';
return false;
}
}
public function Analyze()
{
$info =& $this->getid3->info;
///AH
$info['ac3']['raw']['bsi'] = array();
$thisfile_ac3 =& $info['ac3'];
$thisfile_ac3_raw =& $thisfile_ac3['raw'];
$thisfile_ac3_raw_bsi =& $thisfile_ac3_raw['bsi'];
// http://www.atsc.org/standards/a_52a.pdf
$info['fileformat'] = 'ac3';
// An AC-3 serial coded audio bit stream is made up of a sequence of synchronization frames
// Each synchronization frame contains 6 coded audio blocks (AB), each of which represent 256
// new audio samples per channel. A synchronization information (SI) header at the beginning
// of each frame contains information needed to acquire and maintain synchronization. A
// bit stream information (BSI) header follows SI, and contains parameters describing the coded
// audio service. The coded audio blocks may be followed by an auxiliary data (Aux) field. At the
// end of each frame is an error check field that includes a CRC word for error detection. An
// additional CRC word is located in the SI header, the use of which, by a decoder, is optional.
//
// syncinfo() | bsi() | AB0 | AB1 | AB2 | AB3 | AB4 | AB5 | Aux | CRC
// syncinfo() {
// syncword 16
// crc1 16
// fscod 2
// frmsizecod 6
// } /* end of syncinfo */
$this->fseek($info['avdataoffset']);
$this->AC3header['syncinfo'] = $this->fread(5);
if (strpos($this->AC3header['syncinfo'], self::syncword) === 0) {
$thisfile_ac3_raw['synchinfo']['synchword'] = self::syncword;
$offset = 2;
} else {
if (!$this->isDependencyFor('Matroska')) {
unset($info['fileformat'], $info['ac3']);
return $this->error('Expecting "' . Utils::PrintHexBytes(self::syncword) . '" at offset ' . $info['avdataoffset'] . ', found "' . Utils::PrintHexBytes(substr($this->AC3header['syncinfo'], 0, 2)) . '"');
}
$offset = 0;
$this->fseek(-2, SEEK_CUR);
}
$info['audio']['dataformat'] = 'ac3';
$info['audio']['bitrate_mode'] = 'cbr';
$info['audio']['lossless'] = false;
$thisfile_ac3_raw['synchinfo']['crc1'] = Utils::LittleEndian2Int(substr($this->AC3header['syncinfo'], $offset, 2));
$ac3_synchinfo_fscod_frmsizecod = Utils::LittleEndian2Int(substr($this->AC3header['syncinfo'], $offset + 2, 1));
$thisfile_ac3_raw['synchinfo']['fscod'] = ($ac3_synchinfo_fscod_frmsizecod & 0xc0) >> 6;
$thisfile_ac3_raw['synchinfo']['frmsizecod'] = $ac3_synchinfo_fscod_frmsizecod & 0x3f;
$thisfile_ac3['sample_rate'] = self::sampleRateCodeLookup($thisfile_ac3_raw['synchinfo']['fscod']);
if ($thisfile_ac3_raw['synchinfo']['fscod'] <= 3) {
$info['audio']['sample_rate'] = $thisfile_ac3['sample_rate'];
}
$thisfile_ac3['frame_length'] = self::frameSizeLookup($thisfile_ac3_raw['synchinfo']['frmsizecod'], $thisfile_ac3_raw['synchinfo']['fscod']);
$thisfile_ac3['bitrate'] = self::bitrateLookup($thisfile_ac3_raw['synchinfo']['frmsizecod']);
$info['audio']['bitrate'] = $thisfile_ac3['bitrate'];
$this->AC3header['bsi'] = Utils::BigEndian2Bin($this->fread(15));
$ac3_bsi_offset = 0;
$thisfile_ac3_raw_bsi['bsid'] = $this->readHeaderBSI(5);
if ($thisfile_ac3_raw_bsi['bsid'] > 8) {
// Decoders which can decode version 8 will thus be able to decode version numbers less than 8.
// If this standard is extended by the addition of additional elements or features, a value of bsid greater than 8 will be used.
// Decoders built to this version of the standard will not be able to decode versions with bsid greater than 8.
$this->error('Bit stream identification is version ' . $thisfile_ac3_raw_bsi['bsid'] . ', but getID3() only understands up to version 8');
unset($info['ac3']);
return false;
}
$thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3);
$thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3);
$thisfile_ac3['service_type'] = self::serviceTypeLookup($thisfile_ac3_raw_bsi['bsmod'], $thisfile_ac3_raw_bsi['acmod']);
$ac3_coding_mode = self::audioCodingModeLookup($thisfile_ac3_raw_bsi['acmod']);
foreach ($ac3_coding_mode as $key => $value) {
$thisfile_ac3[$key] = $value;
}
switch ($thisfile_ac3_raw_bsi['acmod']) {
case 0:
case 1:
$info['audio']['channelmode'] = 'mono';
break;
case 3:
case 4:
$info['audio']['channelmode'] = 'stereo';
break;
default:
$info['audio']['channelmode'] = 'surround';
break;
}
$info['audio']['channels'] = $thisfile_ac3['num_channels'];
if ($thisfile_ac3_raw_bsi['acmod'] & 0x1) {
// If the lsb of acmod is a 1, center channel is in use and cmixlev follows in the bit stream.
$thisfile_ac3_raw_bsi['cmixlev'] = $this->readHeaderBSI(2);
$thisfile_ac3['center_mix_level'] = self::centerMixLevelLookup($thisfile_ac3_raw_bsi['cmixlev']);
}
if ($thisfile_ac3_raw_bsi['acmod'] & 0x4) {
// If the msb of acmod is a 1, surround channels are in use and surmixlev follows in the bit stream.
$thisfile_ac3_raw_bsi['surmixlev'] = $this->readHeaderBSI(2);
$thisfile_ac3['surround_mix_level'] = self::surroundMixLevelLookup($thisfile_ac3_raw_bsi['surmixlev']);
}
if ($thisfile_ac3_raw_bsi['acmod'] == 0x2) {
// When operating in the two channel mode, this 2-bit code indicates whether or not the program has been encoded in Dolby Surround.
$thisfile_ac3_raw_bsi['dsurmod'] = $this->readHeaderBSI(2);
$thisfile_ac3['dolby_surround_mode'] = self::dolbySurroundModeLookup($thisfile_ac3_raw_bsi['dsurmod']);
}
$thisfile_ac3_raw_bsi['lfeon'] = (bool) $this->readHeaderBSI(1);
$thisfile_ac3['lfe_enabled'] = $thisfile_ac3_raw_bsi['lfeon'];
if ($thisfile_ac3_raw_bsi['lfeon']) {
//$info['audio']['channels']++;
$info['audio']['channels'] .= '.1';
}
$thisfile_ac3['channels_enabled'] = self::channelsEnabledLookup($thisfile_ac3_raw_bsi['acmod'], $thisfile_ac3_raw_bsi['lfeon']);
// This indicates how far the average dialogue level is below digital 100 percent. Valid values are 1-31.
// The value of 0 is reserved. The values of 1 to 31 are interpreted as -1 dB to -31 dB with respect to digital 100 percent.
$thisfile_ac3_raw_bsi['dialnorm'] = $this->readHeaderBSI(5);
$thisfile_ac3['dialogue_normalization'] = '-' . $thisfile_ac3_raw_bsi['dialnorm'] . 'dB';
$thisfile_ac3_raw_bsi['compre_flag'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['compre_flag']) {
$thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8);
$thisfile_ac3['heavy_compression'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr']);
}
$thisfile_ac3_raw_bsi['langcode_flag'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['langcode_flag']) {
$thisfile_ac3_raw_bsi['langcod'] = $this->readHeaderBSI(8);
}
$thisfile_ac3_raw_bsi['audprodie'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['audprodie']) {
$thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5);
$thisfile_ac3_raw_bsi['roomtyp'] = $this->readHeaderBSI(2);
$thisfile_ac3['mixing_level'] = 80 + $thisfile_ac3_raw_bsi['mixlevel'] . 'dB';
$thisfile_ac3['room_type'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp']);
}
if ($thisfile_ac3_raw_bsi['acmod'] == 0x0) {
// If acmod is 0, then two completely independent program channels (dual mono)
// are encoded into the bit stream, and are referenced as Ch1, Ch2. In this case,
// a number of additional items are present in BSI or audblk to fully describe Ch2.
// This indicates how far the average dialogue level is below digital 100 percent. Valid values are 1-31.
// The value of 0 is reserved. The values of 1 to 31 are interpreted as -1 dB to -31 dB with respect to digital 100 percent.
$thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5);
$thisfile_ac3['dialogue_normalization2'] = '-' . $thisfile_ac3_raw_bsi['dialnorm2'] . 'dB';
$thisfile_ac3_raw_bsi['compre_flag2'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['compre_flag2']) {
$thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8);
$thisfile_ac3['heavy_compression2'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr2']);
}
$thisfile_ac3_raw_bsi['langcode_flag2'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['langcode_flag2']) {
$thisfile_ac3_raw_bsi['langcod2'] = $this->readHeaderBSI(8);
}
$thisfile_ac3_raw_bsi['audprodie2'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['audprodie2']) {
$thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5);
$thisfile_ac3_raw_bsi['roomtyp2'] = $this->readHeaderBSI(2);
$thisfile_ac3['mixing_level2'] = 80 + $thisfile_ac3_raw_bsi['mixlevel2'] . 'dB';
$thisfile_ac3['room_type2'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp2']);
}
}
$thisfile_ac3_raw_bsi['copyright'] = (bool) $this->readHeaderBSI(1);
$thisfile_ac3_raw_bsi['original'] = (bool) $this->readHeaderBSI(1);
$thisfile_ac3_raw_bsi['timecode1_flag'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['timecode1_flag']) {
$thisfile_ac3_raw_bsi['timecode1'] = $this->readHeaderBSI(14);
}
$thisfile_ac3_raw_bsi['timecode2_flag'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['timecode2_flag']) {
$thisfile_ac3_raw_bsi['timecode2'] = $this->readHeaderBSI(14);
}
$thisfile_ac3_raw_bsi['addbsi_flag'] = (bool) $this->readHeaderBSI(1);
if ($thisfile_ac3_raw_bsi['addbsi_flag']) {
$thisfile_ac3_raw_bsi['addbsi_length'] = $this->readHeaderBSI(6);
$this->AC3header['bsi'] .= Utils::BigEndian2Bin($this->fread($thisfile_ac3_raw_bsi['addbsi_length']));
$thisfile_ac3_raw_bsi['addbsi_data'] = substr($this->AC3header['bsi'], $this->BSIoffset, $thisfile_ac3_raw_bsi['addbsi_length'] * 8);
$this->BSIoffset += $thisfile_ac3_raw_bsi['addbsi_length'] * 8;
}
return true;
}
