const syncword = 0x0B77;

		$tempAC3header = $this->fread(100); // should be enough to cover all data, there are some variable-length fields...?

		$this->AC3header['syncinfo']  =     getid3_lib::BigEndian2Int(substr($tempAC3header, 0, 2));

		$this->AC3header['bsi']       =     getid3_lib::BigEndian2Bin(substr($tempAC3header, 2));

		$thisfile_ac3_raw_bsi['bsid'] = (getid3_lib::LittleEndian2Int(substr($tempAC3header, 5, 1)) & 0xF8) >> 3; // AC3 and E-AC3 put the "bsid" version identifier in the same place, but unfortnately the 4 bytes between the syncword and the version identifier are interpreted differently, so grab it here so the following code structure can make sense

		unset($tempAC3header);

		if ($this->AC3header['syncinfo'] !== self::syncword) {

				return $this->error('Expecting "'.dechex(self::syncword).'" at offset '.$info['avdataoffset'].', found "'.dechex($this->AC3header['syncinfo']).'"');

		if ($thisfile_ac3_raw_bsi['bsid'] <= 8) {

			$thisfile_ac3_raw_bsi['crc1']       = getid3_lib::Bin2Dec($this->readHeaderBSI(16));

			$thisfile_ac3_raw_bsi['fscod']      =                     $this->readHeaderBSI(2);   // 5.4.1.3

			$thisfile_ac3_raw_bsi['frmsizecod'] =                     $this->readHeaderBSI(6);   // 5.4.1.4

			if ($thisfile_ac3_raw_bsi['frmsizecod'] > 37) { // binary: 100101 - see Table 5.18 Frame Size Code Table (1 word = 16 bits)

				$this->warning('Unexpected ac3.bsi.frmsizecod value: '.$thisfile_ac3_raw_bsi['frmsizecod'].', bitrate not set correctly');

			}

			$thisfile_ac3_raw_bsi['bsid']  = $this->readHeaderBSI(5); // we already know this from pre-parsing the version identifier, but re-read it to let the bitstream flow as intended

			$thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3);

			$thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3);

			if ($thisfile_ac3_raw_bsi['acmod'] & 0x01) {

				// 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'] & 0x04) {

				// 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'] == 0x02) {

				// 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['flags']['lfeon'] = (bool) $this->readHeaderBSI(1);

			// 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);                 // 5.4.2.8 dialnorm: Dialogue Normalization, 5 Bits

			$thisfile_ac3_raw_bsi['flags']['compr'] = (bool) $this->readHeaderBSI(1);       // 5.4.2.9 compre: Compression Gain Word Exists, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['compr']) {

				$thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8);                // 5.4.2.10 compr: Compression Gain Word, 8 Bits

				$thisfile_ac3['heavy_compression'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr']);

			}

			$thisfile_ac3_raw_bsi['flags']['langcod'] = (bool) $this->readHeaderBSI(1);     // 5.4.2.11 langcode: Language Code Exists, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['langcod']) {

				$thisfile_ac3_raw_bsi['langcod'] = $this->readHeaderBSI(8);              // 5.4.2.12 langcod: Language Code, 8 Bits

			}

			$thisfile_ac3_raw_bsi['flags']['audprodinfo'] = (bool) $this->readHeaderBSI(1);  // 5.4.2.13 audprodie: Audio Production Information Exists, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['audprodinfo']) {

				$thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5);             // 5.4.2.14 mixlevel: Mixing Level, 5 Bits

				$thisfile_ac3_raw_bsi['roomtyp']  = $this->readHeaderBSI(2);             // 5.4.2.15 roomtyp: Room Type, 2 Bits

				$thisfile_ac3['mixing_level'] = (80 + $thisfile_ac3_raw_bsi['mixlevel']).'dB';

				$thisfile_ac3['room_type']    = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp']);

			}

			$thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5);                // 5.4.2.16 dialnorm2: Dialogue Normalization, ch2, 5 Bits

			$thisfile_ac3['dialogue_normalization2'] = '-'.$thisfile_ac3_raw_bsi['dialnorm2'].'dB';  // 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['flags']['compr2'] = (bool) $this->readHeaderBSI(1);       // 5.4.2.17 compr2e: Compression Gain Word Exists, ch2, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['compr2']) {

				$thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8);               // 5.4.2.18 compr2: Compression Gain Word, ch2, 8 Bits

				$thisfile_ac3['heavy_compression2'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr2']);

			}

			$thisfile_ac3_raw_bsi['flags']['langcod2'] = (bool) $this->readHeaderBSI(1);    // 5.4.2.19 langcod2e: Language Code Exists, ch2, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['langcod2']) {

				$thisfile_ac3_raw_bsi['langcod2'] = $this->readHeaderBSI(8);             // 5.4.2.20 langcod2: Language Code, ch2, 8 Bits

			}

			$thisfile_ac3_raw_bsi['flags']['audprodinfo2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.21 audprodi2e: Audio Production Information Exists, ch2, 1 Bit

			if ($thisfile_ac3_raw_bsi['flags']['audprodinfo2']) {

				$thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5);            // 5.4.2.22 mixlevel2: Mixing Level, ch2, 5 Bits

				$thisfile_ac3_raw_bsi['roomtyp2']  = $this->readHeaderBSI(2);            // 5.4.2.23 roomtyp2: Room Type, ch2, 2 Bits

				$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);         // 5.4.2.24 copyrightb: Copyright Bit, 1 Bit

			$thisfile_ac3_raw_bsi['original']  = (bool) $this->readHeaderBSI(1);         // 5.4.2.25 origbs: Original Bit Stream, 1 Bit

			$thisfile_ac3_raw_bsi['flags']['timecod1'] = $this->readHeaderBSI(2);            // 5.4.2.26 timecod1e, timcode2e: Time Code (first and second) Halves Exist, 2 Bits

			if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x01) {

				$thisfile_ac3_raw_bsi['timecod1'] = $this->readHeaderBSI(14);            // 5.4.2.27 timecod1: Time code first half, 14 bits

				$thisfile_ac3['timecode1'] = 0;

				$thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x3E00) >>  9) * 3600;  // The first 5 bits of this 14-bit field represent the time in hours, with valid values of 0�23

				$thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x01F8) >>  3) *   60;  // The next 6 bits represent the time in minutes, with valid values of 0�59

				$thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x0003) >>  0) *    8;  // The final 3 bits represents the time in 8 second increments, with valid values of 0�7 (representing 0, 8, 16, ... 56 seconds)

			}

			if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x02) {

				$thisfile_ac3_raw_bsi['timecod2'] = $this->readHeaderBSI(14);            // 5.4.2.28 timecod2: Time code second half, 14 bits

				$thisfile_ac3['timecode2'] = 0;

				$thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x3800) >> 11) *   1;              // The first 3 bits of this 14-bit field represent the time in seconds, with valid values from 0�7 (representing 0-7 seconds)

				$thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x07C0) >>  6) *  (1 / 30);        // The next 5 bits represents the time in frames, with valid values from 0�29 (one frame = 1/30th of a second)

				$thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x003F) >>  0) * ((1 / 30) / 60);  // The final 6 bits represents fractions of 1/64 of a frame, with valid values from 0�63

			}

			$thisfile_ac3_raw_bsi['flags']['addbsi'] = (bool) $this->readHeaderBSI(1);

			if ($thisfile_ac3_raw_bsi['flags']['addbsi']) {

				$thisfile_ac3_raw_bsi['addbsi_length'] = $this->readHeaderBSI(6) + 1; // This 6-bit code, which exists only if addbside is a 1, indicates the length in bytes of additional bit stream information. The valid range of addbsil is 0�63, indicating 1�64 additional bytes, respectively.

				$this->AC3header['bsi'] .= getid3_lib::BigEndian2Bin($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;

			}

		} elseif ($thisfile_ac3_raw_bsi['bsid'] <= 16) { // E-AC3

$this->error('E-AC3 parsing is incomplete and experimental in this version of getID3 ('.$this->getid3->version().'). Notably the bitrate calculations are wrong -- value might (or not) be correct, but it is not calculated correctly. Email info@getid3.org if you know how to calculate EAC3 bitrate correctly.');

			$info['audio']['dataformat'] = 'eac3';

			$thisfile_ac3_raw_bsi['strmtyp']          =        $this->readHeaderBSI(2);

			$thisfile_ac3_raw_bsi['substreamid']      =        $this->readHeaderBSI(3);

			$thisfile_ac3_raw_bsi['frmsiz']           =        $this->readHeaderBSI(11);

			$thisfile_ac3_raw_bsi['fscod']            =        $this->readHeaderBSI(2);

			if ($thisfile_ac3_raw_bsi['fscod'] == 3) {

				$thisfile_ac3_raw_bsi['fscod2']       =        $this->readHeaderBSI(2);

				$thisfile_ac3_raw_bsi['numblkscod'] = 3; // six blocks per syncframe

			} else {

				$thisfile_ac3_raw_bsi['numblkscod']   =        $this->readHeaderBSI(2);

			}

			$thisfile_ac3['bsi']['blocks_per_sync_frame'] = self::blocksPerSyncFrame($thisfile_ac3_raw_bsi['numblkscod']);

			$thisfile_ac3_raw_bsi['acmod']            =        $this->readHeaderBSI(3);

			$thisfile_ac3_raw_bsi['flags']['lfeon']   = (bool) $this->readHeaderBSI(1);

			$thisfile_ac3_raw_bsi['bsid']             =        $this->readHeaderBSI(5); // we already know this from pre-parsing the version identifier, but re-read it to let the bitstream flow as intended

			$thisfile_ac3_raw_bsi['dialnorm']         =        $this->readHeaderBSI(5);

			$thisfile_ac3_raw_bsi['flags']['compr']       = (bool) $this->readHeaderBSI(1);

			if ($thisfile_ac3_raw_bsi['flags']['compr']) {

				$thisfile_ac3_raw_bsi['compr']        =        $this->readHeaderBSI(8);

			}

			if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)

				$thisfile_ac3_raw_bsi['dialnorm2']    =        $this->readHeaderBSI(5);

				$thisfile_ac3_raw_bsi['flags']['compr2']  = (bool) $this->readHeaderBSI(1);

				if ($thisfile_ac3_raw_bsi['flags']['compr2']) {

					$thisfile_ac3_raw_bsi['compr2']   =        $this->readHeaderBSI(8);

				}

			}

			if ($thisfile_ac3_raw_bsi['strmtyp'] == 1) { // if dependent stream

				$thisfile_ac3_raw_bsi['flags']['chanmap'] = (bool) $this->readHeaderBSI(1);

				if ($thisfile_ac3_raw_bsi['flags']['chanmap']) {

					$thisfile_ac3_raw_bsi['chanmap']  =        $this->readHeaderBSI(8);

				}

			}

			$thisfile_ac3_raw_bsi['flags']['mixmdat']     = (bool) $this->readHeaderBSI(1);

			if ($thisfile_ac3_raw_bsi['flags']['mixmdat']) { // Mixing metadata

				if ($thisfile_ac3_raw_bsi['acmod'] > 2) { // if more than 2 channels

					$thisfile_ac3_raw_bsi['dmixmod']  =        $this->readHeaderBSI(2);

				}

				if (($thisfile_ac3_raw_bsi['acmod'] & 0x01) && ($thisfile_ac3_raw_bsi['acmod'] > 2)) { // if three front channels exist

					$thisfile_ac3_raw_bsi['ltrtcmixlev'] =        $this->readHeaderBSI(3);

					$thisfile_ac3_raw_bsi['lorocmixlev'] =        $this->readHeaderBSI(3);

				}

				if ($thisfile_ac3_raw_bsi['acmod'] & 0x04) { // if a surround channel exists

					$thisfile_ac3_raw_bsi['ltrtsurmixlev'] =        $this->readHeaderBSI(3);

					$thisfile_ac3_raw_bsi['lorosurmixlev'] =        $this->readHeaderBSI(3);

				}

				if ($thisfile_ac3_raw_bsi['flags']['lfeon']) { // if the LFE channel exists

					$thisfile_ac3_raw_bsi['flags']['lfemixlevcod'] = (bool) $this->readHeaderBSI(1);

					if ($thisfile_ac3_raw_bsi['flags']['lfemixlevcod']) {

						$thisfile_ac3_raw_bsi['lfemixlevcod']  =        $this->readHeaderBSI(5);

					}

				}

				if ($thisfile_ac3_raw_bsi['strmtyp'] == 0) { // if independent stream

					$thisfile_ac3_raw_bsi['flags']['pgmscl'] = (bool) $this->readHeaderBSI(1);

					if ($thisfile_ac3_raw_bsi['flags']['pgmscl']) {

						$thisfile_ac3_raw_bsi['pgmscl']  =        $this->readHeaderBSI(6);

					}

					if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)

						$thisfile_ac3_raw_bsi['flags']['pgmscl2'] = (bool) $this->readHeaderBSI(1);

						if ($thisfile_ac3_raw_bsi['flags']['pgmscl2']) {

							$thisfile_ac3_raw_bsi['pgmscl2']  =        $this->readHeaderBSI(6);

						}

					}

					$thisfile_ac3_raw_bsi['flags']['extpgmscl'] = (bool) $this->readHeaderBSI(1);

					if ($thisfile_ac3_raw_bsi['flags']['extpgmscl']) {

						$thisfile_ac3_raw_bsi['extpgmscl']  =        $this->readHeaderBSI(6);

					}

					$thisfile_ac3_raw_bsi['mixdef']  =        $this->readHeaderBSI(2);

					if ($thisfile_ac3_raw_bsi['mixdef'] == 1) { // mixing option 2

						$thisfile_ac3_raw_bsi['premixcmpsel']  = (bool) $this->readHeaderBSI(1);

						$thisfile_ac3_raw_bsi['drcsrc']        = (bool) $this->readHeaderBSI(1);

						$thisfile_ac3_raw_bsi['premixcmpscl']  =        $this->readHeaderBSI(3);

					} elseif ($thisfile_ac3_raw_bsi['mixdef'] == 2) { // mixing option 3

						$thisfile_ac3_raw_bsi['mixdata']       =        $this->readHeaderBSI(12);

					} elseif ($thisfile_ac3_raw_bsi['mixdef'] == 3) { // mixing option 4

						$mixdefbitsread = 0;

						$thisfile_ac3_raw_bsi['mixdeflen']     =        $this->readHeaderBSI(5); $mixdefbitsread += 5;

						$thisfile_ac3_raw_bsi['flags']['mixdata2'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

						if ($thisfile_ac3_raw_bsi['flags']['mixdata2']) {

							$thisfile_ac3_raw_bsi['premixcmpsel']  = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							$thisfile_ac3_raw_bsi['drcsrc']        = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							$thisfile_ac3_raw_bsi['premixcmpscl']  =        $this->readHeaderBSI(3); $mixdefbitsread += 3;

							$thisfile_ac3_raw_bsi['flags']['extpgmlscl']   = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmlscl']) {

								$thisfile_ac3_raw_bsi['extpgmlscl']    =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['extpgmcscl']   = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmcscl']) {

								$thisfile_ac3_raw_bsi['extpgmcscl']    =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['extpgmrscl']   = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmrscl']) {

								$thisfile_ac3_raw_bsi['extpgmrscl']    =        $this->readHeaderBSI(4);

							}

							$thisfile_ac3_raw_bsi['flags']['extpgmlsscl']  = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmlsscl']) {

								$thisfile_ac3_raw_bsi['extpgmlsscl']   =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['extpgmrsscl']  = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmrsscl']) {

								$thisfile_ac3_raw_bsi['extpgmrsscl']   =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['extpgmlfescl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['extpgmlfescl']) {

								$thisfile_ac3_raw_bsi['extpgmlfescl']  =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['dmixscl']      = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['dmixscl']) {

								$thisfile_ac3_raw_bsi['dmixscl']       =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

							}

							$thisfile_ac3_raw_bsi['flags']['addch']        = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['addch']) {

								$thisfile_ac3_raw_bsi['flags']['extpgmaux1scl']   = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

								if ($thisfile_ac3_raw_bsi['flags']['extpgmaux1scl']) {

									$thisfile_ac3_raw_bsi['extpgmaux1scl']    =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

								}

								$thisfile_ac3_raw_bsi['flags']['extpgmaux2scl']   = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

								if ($thisfile_ac3_raw_bsi['flags']['extpgmaux2scl']) {

									$thisfile_ac3_raw_bsi['extpgmaux2scl']    =        $this->readHeaderBSI(4); $mixdefbitsread += 4;

								}

							}

						}

						$thisfile_ac3_raw_bsi['flags']['mixdata3'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

						if ($thisfile_ac3_raw_bsi['flags']['mixdata3']) {

							$thisfile_ac3_raw_bsi['spchdat']   =        $this->readHeaderBSI(5); $mixdefbitsread += 5;

							$thisfile_ac3_raw_bsi['flags']['addspchdat'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

							if ($thisfile_ac3_raw_bsi['flags']['addspchdat']) {

								$thisfile_ac3_raw_bsi['spchdat1']   =         $this->readHeaderBSI(5); $mixdefbitsread += 5;

								$thisfile_ac3_raw_bsi['spchan1att'] =         $this->readHeaderBSI(2); $mixdefbitsread += 2;

								$thisfile_ac3_raw_bsi['flags']['addspchdat1'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;

								if ($thisfile_ac3_raw_bsi['flags']['addspchdat1']) {

									$thisfile_ac3_raw_bsi['spchdat2']   =         $this->readHeaderBSI(5); $mixdefbitsread += 5;

									$thisfile_ac3_raw_bsi['spchan2att'] =         $this->readHeaderBSI(3); $mixdefbitsread += 3;

								}

							}

						}

						$mixdata_bits = (8 * ($thisfile_ac3_raw_bsi['mixdeflen'] + 2)) - $mixdefbitsread;

						$mixdata_fill = (($mixdata_bits % 8) ? 8 - ($mixdata_bits % 8) : 0);

						$thisfile_ac3_raw_bsi['mixdata']     =        $this->readHeaderBSI($mixdata_bits);