ILIAS  release_5-4 Revision v5.4.26-12-gabc799a52e6
module.audio.ac3.php
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1 <?php
4 // available at http://getid3.sourceforge.net //
5 // or http://www.getid3.org //
6 // also https://github.com/JamesHeinrich/getID3 //
8 // See readme.txt for more details //
10 // //
11 // module.audio.ac3.php //
12 // module for analyzing AC-3 (aka Dolby Digital) audio files //
13 // dependencies: NONE //
14 // ///
16 
17 
18 class getid3_ac3 extends getid3_handler
19 {
20  private $AC3header = array();
21  private $BSIoffset = 0;
22 
23  const syncword = 0x0B77;
24 
25  public function Analyze() {
26  $info = &$this->getid3->info;
27 
29  $info['ac3']['raw']['bsi'] = array();
30  $thisfile_ac3 = &$info['ac3'];
31  $thisfile_ac3_raw = &$thisfile_ac3['raw'];
32  $thisfile_ac3_raw_bsi = &$thisfile_ac3_raw['bsi'];
33 
34 
35  // http://www.atsc.org/standards/a_52a.pdf
36 
37  $info['fileformat'] = 'ac3';
38 
39  // An AC-3 serial coded audio bit stream is made up of a sequence of synchronization frames
40  // Each synchronization frame contains 6 coded audio blocks (AB), each of which represent 256
41  // new audio samples per channel. A synchronization information (SI) header at the beginning
42  // of each frame contains information needed to acquire and maintain synchronization. A
43  // bit stream information (BSI) header follows SI, and contains parameters describing the coded
44  // audio service. The coded audio blocks may be followed by an auxiliary data (Aux) field. At the
45  // end of each frame is an error check field that includes a CRC word for error detection. An
46  // additional CRC word is located in the SI header, the use of which, by a decoder, is optional.
47  //
48  // syncinfo() | bsi() | AB0 | AB1 | AB2 | AB3 | AB4 | AB5 | Aux | CRC
49 
50  // syncinfo() {
51  // syncword 16
52  // crc1 16
53  // fscod 2
54  // frmsizecod 6
55  // } /* end of syncinfo */
56 
57  $this->fseek($info['avdataoffset']);
58  $tempAC3header = $this->fread(100); // should be enough to cover all data, there are some variable-length fields...?
59  $this->AC3header['syncinfo'] = getid3_lib::BigEndian2Int(substr($tempAC3header, 0, 2));
60  $this->AC3header['bsi'] = getid3_lib::BigEndian2Bin(substr($tempAC3header, 2));
61  $thisfile_ac3_raw_bsi['bsid'] = (getid3_lib::LittleEndian2Int(substr($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
62  unset($tempAC3header);
63 
64  if ($this->AC3header['syncinfo'] !== self::syncword) {
65  if (!$this->isDependencyFor('matroska')) {
66  unset($info['fileformat'], $info['ac3']);
67  return $this->error('Expecting "'.dechex(self::syncword).'" at offset '.$info['avdataoffset'].', found "'.dechex($this->AC3header['syncinfo']).'"');
68  }
69  }
70 
71  $info['audio']['dataformat'] = 'ac3';
72  $info['audio']['bitrate_mode'] = 'cbr';
73  $info['audio']['lossless'] = false;
74 
75  if ($thisfile_ac3_raw_bsi['bsid'] <= 8) {
76 
77  $thisfile_ac3_raw_bsi['crc1'] = getid3_lib::Bin2Dec($this->readHeaderBSI(16));
78  $thisfile_ac3_raw_bsi['fscod'] = $this->readHeaderBSI(2); // 5.4.1.3
79  $thisfile_ac3_raw_bsi['frmsizecod'] = $this->readHeaderBSI(6); // 5.4.1.4
80  if ($thisfile_ac3_raw_bsi['frmsizecod'] > 37) { // binary: 100101 - see Table 5.18 Frame Size Code Table (1 word = 16 bits)
81  $this->warning('Unexpected ac3.bsi.frmsizecod value: '.$thisfile_ac3_raw_bsi['frmsizecod'].', bitrate not set correctly');
82  }
83 
84  $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
85  $thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3);
86  $thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3);
87 
88  if ($thisfile_ac3_raw_bsi['acmod'] & 0x01) {
89  // If the lsb of acmod is a 1, center channel is in use and cmixlev follows in the bit stream.
90  $thisfile_ac3_raw_bsi['cmixlev'] = $this->readHeaderBSI(2);
91  $thisfile_ac3['center_mix_level'] = self::centerMixLevelLookup($thisfile_ac3_raw_bsi['cmixlev']);
92  }
93 
94  if ($thisfile_ac3_raw_bsi['acmod'] & 0x04) {
95  // If the msb of acmod is a 1, surround channels are in use and surmixlev follows in the bit stream.
96  $thisfile_ac3_raw_bsi['surmixlev'] = $this->readHeaderBSI(2);
97  $thisfile_ac3['surround_mix_level'] = self::surroundMixLevelLookup($thisfile_ac3_raw_bsi['surmixlev']);
98  }
99 
100  if ($thisfile_ac3_raw_bsi['acmod'] == 0x02) {
101  // When operating in the two channel mode, this 2-bit code indicates whether or not the program has been encoded in Dolby Surround.
102  $thisfile_ac3_raw_bsi['dsurmod'] = $this->readHeaderBSI(2);
103  $thisfile_ac3['dolby_surround_mode'] = self::dolbySurroundModeLookup($thisfile_ac3_raw_bsi['dsurmod']);
104  }
105 
106  $thisfile_ac3_raw_bsi['flags']['lfeon'] = (bool) $this->readHeaderBSI(1);
107 
108  // This indicates how far the average dialogue level is below digital 100 percent. Valid values are 1-31.
109  // 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.
110  $thisfile_ac3_raw_bsi['dialnorm'] = $this->readHeaderBSI(5); // 5.4.2.8 dialnorm: Dialogue Normalization, 5 Bits
111 
112  $thisfile_ac3_raw_bsi['flags']['compr'] = (bool) $this->readHeaderBSI(1); // 5.4.2.9 compre: Compression Gain Word Exists, 1 Bit
113  if ($thisfile_ac3_raw_bsi['flags']['compr']) {
114  $thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8); // 5.4.2.10 compr: Compression Gain Word, 8 Bits
115  $thisfile_ac3['heavy_compression'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr']);
116  }
117 
118  $thisfile_ac3_raw_bsi['flags']['langcod'] = (bool) $this->readHeaderBSI(1); // 5.4.2.11 langcode: Language Code Exists, 1 Bit
119  if ($thisfile_ac3_raw_bsi['flags']['langcod']) {
120  $thisfile_ac3_raw_bsi['langcod'] = $this->readHeaderBSI(8); // 5.4.2.12 langcod: Language Code, 8 Bits
121  }
122 
123  $thisfile_ac3_raw_bsi['flags']['audprodinfo'] = (bool) $this->readHeaderBSI(1); // 5.4.2.13 audprodie: Audio Production Information Exists, 1 Bit
124  if ($thisfile_ac3_raw_bsi['flags']['audprodinfo']) {
125  $thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5); // 5.4.2.14 mixlevel: Mixing Level, 5 Bits
126  $thisfile_ac3_raw_bsi['roomtyp'] = $this->readHeaderBSI(2); // 5.4.2.15 roomtyp: Room Type, 2 Bits
127 
128  $thisfile_ac3['mixing_level'] = (80 + $thisfile_ac3_raw_bsi['mixlevel']).'dB';
129  $thisfile_ac3['room_type'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp']);
130  }
131 
132 
133  $thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5); // 5.4.2.16 dialnorm2: Dialogue Normalization, ch2, 5 Bits
134  $thisfile_ac3['dialogue_normalization2'] = '-'.$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.
135 
136  $thisfile_ac3_raw_bsi['flags']['compr2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.17 compr2e: Compression Gain Word Exists, ch2, 1 Bit
137  if ($thisfile_ac3_raw_bsi['flags']['compr2']) {
138  $thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8); // 5.4.2.18 compr2: Compression Gain Word, ch2, 8 Bits
139  $thisfile_ac3['heavy_compression2'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr2']);
140  }
141 
142  $thisfile_ac3_raw_bsi['flags']['langcod2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.19 langcod2e: Language Code Exists, ch2, 1 Bit
143  if ($thisfile_ac3_raw_bsi['flags']['langcod2']) {
144  $thisfile_ac3_raw_bsi['langcod2'] = $this->readHeaderBSI(8); // 5.4.2.20 langcod2: Language Code, ch2, 8 Bits
145  }
146 
147  $thisfile_ac3_raw_bsi['flags']['audprodinfo2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.21 audprodi2e: Audio Production Information Exists, ch2, 1 Bit
148  if ($thisfile_ac3_raw_bsi['flags']['audprodinfo2']) {
149  $thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5); // 5.4.2.22 mixlevel2: Mixing Level, ch2, 5 Bits
150  $thisfile_ac3_raw_bsi['roomtyp2'] = $this->readHeaderBSI(2); // 5.4.2.23 roomtyp2: Room Type, ch2, 2 Bits
151 
152  $thisfile_ac3['mixing_level2'] = (80 + $thisfile_ac3_raw_bsi['mixlevel2']).'dB';
153  $thisfile_ac3['room_type2'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp2']);
154  }
155 
156  $thisfile_ac3_raw_bsi['copyright'] = (bool) $this->readHeaderBSI(1); // 5.4.2.24 copyrightb: Copyright Bit, 1 Bit
157 
158  $thisfile_ac3_raw_bsi['original'] = (bool) $this->readHeaderBSI(1); // 5.4.2.25 origbs: Original Bit Stream, 1 Bit
159 
160  $thisfile_ac3_raw_bsi['flags']['timecod1'] = $this->readHeaderBSI(2); // 5.4.2.26 timecod1e, timcode2e: Time Code (first and second) Halves Exist, 2 Bits
161  if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x01) {
162  $thisfile_ac3_raw_bsi['timecod1'] = $this->readHeaderBSI(14); // 5.4.2.27 timecod1: Time code first half, 14 bits
163  $thisfile_ac3['timecode1'] = 0;
164  $thisfile_ac3['timecode1'] += (($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
165  $thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x01F8) >> 3) * 60; // The next 6 bits represent the time in minutes, with valid values of 0–59
166  $thisfile_ac3['timecode1'] += (($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)
167  }
168  if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x02) {
169  $thisfile_ac3_raw_bsi['timecod2'] = $this->readHeaderBSI(14); // 5.4.2.28 timecod2: Time code second half, 14 bits
170  $thisfile_ac3['timecode2'] = 0;
171  $thisfile_ac3['timecode2'] += (($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)
172  $thisfile_ac3['timecode2'] += (($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)
173  $thisfile_ac3['timecode2'] += (($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
174  }
175 
176  $thisfile_ac3_raw_bsi['flags']['addbsi'] = (bool) $this->readHeaderBSI(1);
177  if ($thisfile_ac3_raw_bsi['flags']['addbsi']) {
178  $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.
179 
180  $this->AC3header['bsi'] .= getid3_lib::BigEndian2Bin($this->fread($thisfile_ac3_raw_bsi['addbsi_length']));
181 
182  $thisfile_ac3_raw_bsi['addbsi_data'] = substr($this->AC3header['bsi'], $this->BSIoffset, $thisfile_ac3_raw_bsi['addbsi_length'] * 8);
183  $this->BSIoffset += $thisfile_ac3_raw_bsi['addbsi_length'] * 8;
184  }
185 
186 
187  } elseif ($thisfile_ac3_raw_bsi['bsid'] <= 16) { // E-AC3
188 
189 
190 $this->error('E-AC3 parsing is incomplete and experimental in this version of getID3 ('.$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.');
191  $info['audio']['dataformat'] = 'eac3';
192 
193  $thisfile_ac3_raw_bsi['strmtyp'] = $this->readHeaderBSI(2);
194  $thisfile_ac3_raw_bsi['substreamid'] = $this->readHeaderBSI(3);
195  $thisfile_ac3_raw_bsi['frmsiz'] = $this->readHeaderBSI(11);
196  $thisfile_ac3_raw_bsi['fscod'] = $this->readHeaderBSI(2);
197  if ($thisfile_ac3_raw_bsi['fscod'] == 3) {
198  $thisfile_ac3_raw_bsi['fscod2'] = $this->readHeaderBSI(2);
199  $thisfile_ac3_raw_bsi['numblkscod'] = 3; // six blocks per syncframe
200  } else {
201  $thisfile_ac3_raw_bsi['numblkscod'] = $this->readHeaderBSI(2);
202  }
203  $thisfile_ac3['bsi']['blocks_per_sync_frame'] = self::blocksPerSyncFrame($thisfile_ac3_raw_bsi['numblkscod']);
204  $thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3);
205  $thisfile_ac3_raw_bsi['flags']['lfeon'] = (bool) $this->readHeaderBSI(1);
206  $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
207  $thisfile_ac3_raw_bsi['dialnorm'] = $this->readHeaderBSI(5);
208  $thisfile_ac3_raw_bsi['flags']['compr'] = (bool) $this->readHeaderBSI(1);
209  if ($thisfile_ac3_raw_bsi['flags']['compr']) {
210  $thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8);
211  }
212  if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)
213  $thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5);
214  $thisfile_ac3_raw_bsi['flags']['compr2'] = (bool) $this->readHeaderBSI(1);
215  if ($thisfile_ac3_raw_bsi['flags']['compr2']) {
216  $thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8);
217  }
218  }
219  if ($thisfile_ac3_raw_bsi['strmtyp'] == 1) { // if dependent stream
220  $thisfile_ac3_raw_bsi['flags']['chanmap'] = (bool) $this->readHeaderBSI(1);
221  if ($thisfile_ac3_raw_bsi['flags']['chanmap']) {
222  $thisfile_ac3_raw_bsi['chanmap'] = $this->readHeaderBSI(8);
223  }
224  }
225  $thisfile_ac3_raw_bsi['flags']['mixmdat'] = (bool) $this->readHeaderBSI(1);
226  if ($thisfile_ac3_raw_bsi['flags']['mixmdat']) { // Mixing metadata
227  if ($thisfile_ac3_raw_bsi['acmod'] > 2) { // if more than 2 channels
228  $thisfile_ac3_raw_bsi['dmixmod'] = $this->readHeaderBSI(2);
229  }
230  if (($thisfile_ac3_raw_bsi['acmod'] & 0x01) && ($thisfile_ac3_raw_bsi['acmod'] > 2)) { // if three front channels exist
231  $thisfile_ac3_raw_bsi['ltrtcmixlev'] = $this->readHeaderBSI(3);
232  $thisfile_ac3_raw_bsi['lorocmixlev'] = $this->readHeaderBSI(3);
233  }
234  if ($thisfile_ac3_raw_bsi['acmod'] & 0x04) { // if a surround channel exists
235  $thisfile_ac3_raw_bsi['ltrtsurmixlev'] = $this->readHeaderBSI(3);
236  $thisfile_ac3_raw_bsi['lorosurmixlev'] = $this->readHeaderBSI(3);
237  }
238  if ($thisfile_ac3_raw_bsi['flags']['lfeon']) { // if the LFE channel exists
239  $thisfile_ac3_raw_bsi['flags']['lfemixlevcod'] = (bool) $this->readHeaderBSI(1);
240  if ($thisfile_ac3_raw_bsi['flags']['lfemixlevcod']) {
241  $thisfile_ac3_raw_bsi['lfemixlevcod'] = $this->readHeaderBSI(5);
242  }
243  }
244  if ($thisfile_ac3_raw_bsi['strmtyp'] == 0) { // if independent stream
245  $thisfile_ac3_raw_bsi['flags']['pgmscl'] = (bool) $this->readHeaderBSI(1);
246  if ($thisfile_ac3_raw_bsi['flags']['pgmscl']) {
247  $thisfile_ac3_raw_bsi['pgmscl'] = $this->readHeaderBSI(6);
248  }
249  if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)
250  $thisfile_ac3_raw_bsi['flags']['pgmscl2'] = (bool) $this->readHeaderBSI(1);
251  if ($thisfile_ac3_raw_bsi['flags']['pgmscl2']) {
252  $thisfile_ac3_raw_bsi['pgmscl2'] = $this->readHeaderBSI(6);
253  }
254  }
255  $thisfile_ac3_raw_bsi['flags']['extpgmscl'] = (bool) $this->readHeaderBSI(1);
256  if ($thisfile_ac3_raw_bsi['flags']['extpgmscl']) {
257  $thisfile_ac3_raw_bsi['extpgmscl'] = $this->readHeaderBSI(6);
258  }
259  $thisfile_ac3_raw_bsi['mixdef'] = $this->readHeaderBSI(2);
260  if ($thisfile_ac3_raw_bsi['mixdef'] == 1) { // mixing option 2
261  $thisfile_ac3_raw_bsi['premixcmpsel'] = (bool) $this->readHeaderBSI(1);
262  $thisfile_ac3_raw_bsi['drcsrc'] = (bool) $this->readHeaderBSI(1);
263  $thisfile_ac3_raw_bsi['premixcmpscl'] = $this->readHeaderBSI(3);
264  } elseif ($thisfile_ac3_raw_bsi['mixdef'] == 2) { // mixing option 3
265  $thisfile_ac3_raw_bsi['mixdata'] = $this->readHeaderBSI(12);
266  } elseif ($thisfile_ac3_raw_bsi['mixdef'] == 3) { // mixing option 4
267  $mixdefbitsread = 0;
268  $thisfile_ac3_raw_bsi['mixdeflen'] = $this->readHeaderBSI(5); $mixdefbitsread += 5;
269  $thisfile_ac3_raw_bsi['flags']['mixdata2'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
270  if ($thisfile_ac3_raw_bsi['flags']['mixdata2']) {
271  $thisfile_ac3_raw_bsi['premixcmpsel'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
272  $thisfile_ac3_raw_bsi['drcsrc'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
273  $thisfile_ac3_raw_bsi['premixcmpscl'] = $this->readHeaderBSI(3); $mixdefbitsread += 3;
274  $thisfile_ac3_raw_bsi['flags']['extpgmlscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
275  if ($thisfile_ac3_raw_bsi['flags']['extpgmlscl']) {
276  $thisfile_ac3_raw_bsi['extpgmlscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
277  }
278  $thisfile_ac3_raw_bsi['flags']['extpgmcscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
279  if ($thisfile_ac3_raw_bsi['flags']['extpgmcscl']) {
280  $thisfile_ac3_raw_bsi['extpgmcscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
281  }
282  $thisfile_ac3_raw_bsi['flags']['extpgmrscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
283  if ($thisfile_ac3_raw_bsi['flags']['extpgmrscl']) {
284  $thisfile_ac3_raw_bsi['extpgmrscl'] = $this->readHeaderBSI(4);
285  }
286  $thisfile_ac3_raw_bsi['flags']['extpgmlsscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
287  if ($thisfile_ac3_raw_bsi['flags']['extpgmlsscl']) {
288  $thisfile_ac3_raw_bsi['extpgmlsscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
289  }
290  $thisfile_ac3_raw_bsi['flags']['extpgmrsscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
291  if ($thisfile_ac3_raw_bsi['flags']['extpgmrsscl']) {
292  $thisfile_ac3_raw_bsi['extpgmrsscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
293  }
294  $thisfile_ac3_raw_bsi['flags']['extpgmlfescl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
295  if ($thisfile_ac3_raw_bsi['flags']['extpgmlfescl']) {
296  $thisfile_ac3_raw_bsi['extpgmlfescl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
297  }
298  $thisfile_ac3_raw_bsi['flags']['dmixscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
299  if ($thisfile_ac3_raw_bsi['flags']['dmixscl']) {
300  $thisfile_ac3_raw_bsi['dmixscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
301  }
302  $thisfile_ac3_raw_bsi['flags']['addch'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
303  if ($thisfile_ac3_raw_bsi['flags']['addch']) {
304  $thisfile_ac3_raw_bsi['flags']['extpgmaux1scl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
305  if ($thisfile_ac3_raw_bsi['flags']['extpgmaux1scl']) {
306  $thisfile_ac3_raw_bsi['extpgmaux1scl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
307  }
308  $thisfile_ac3_raw_bsi['flags']['extpgmaux2scl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
309  if ($thisfile_ac3_raw_bsi['flags']['extpgmaux2scl']) {
310  $thisfile_ac3_raw_bsi['extpgmaux2scl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4;
311  }
312  }
313  }
314  $thisfile_ac3_raw_bsi['flags']['mixdata3'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
315  if ($thisfile_ac3_raw_bsi['flags']['mixdata3']) {
316  $thisfile_ac3_raw_bsi['spchdat'] = $this->readHeaderBSI(5); $mixdefbitsread += 5;
317  $thisfile_ac3_raw_bsi['flags']['addspchdat'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
318  if ($thisfile_ac3_raw_bsi['flags']['addspchdat']) {
319  $thisfile_ac3_raw_bsi['spchdat1'] = $this->readHeaderBSI(5); $mixdefbitsread += 5;
320  $thisfile_ac3_raw_bsi['spchan1att'] = $this->readHeaderBSI(2); $mixdefbitsread += 2;
321  $thisfile_ac3_raw_bsi['flags']['addspchdat1'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1;
322  if ($thisfile_ac3_raw_bsi['flags']['addspchdat1']) {
323  $thisfile_ac3_raw_bsi['spchdat2'] = $this->readHeaderBSI(5); $mixdefbitsread += 5;
324  $thisfile_ac3_raw_bsi['spchan2att'] = $this->readHeaderBSI(3); $mixdefbitsread += 3;
325  }
326  }
327  }
328  $mixdata_bits = (8 * ($thisfile_ac3_raw_bsi['mixdeflen'] + 2)) - $mixdefbitsread;
329  $mixdata_fill = (($mixdata_bits % 8) ? 8 - ($mixdata_bits % 8) : 0);
330  $thisfile_ac3_raw_bsi['mixdata'] = $this->readHeaderBSI($mixdata_bits);
331  $thisfile_ac3_raw_bsi['mixdatafill'] = $this->readHeaderBSI($mixdata_fill);
332  unset($mixdefbitsread, $mixdata_bits, $mixdata_fill);
333  }
334  if ($thisfile_ac3_raw_bsi['acmod'] < 2) { // if mono or dual mono source
335  $thisfile_ac3_raw_bsi['flags']['paninfo'] = (bool) $this->readHeaderBSI(1);
336  if ($thisfile_ac3_raw_bsi['flags']['paninfo']) {
337  $thisfile_ac3_raw_bsi['panmean'] = $this->readHeaderBSI(8);
338  $thisfile_ac3_raw_bsi['paninfo'] = $this->readHeaderBSI(6);
339  }
340  if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)
341  $thisfile_ac3_raw_bsi['flags']['paninfo2'] = (bool) $this->readHeaderBSI(1);
342  if ($thisfile_ac3_raw_bsi['flags']['paninfo2']) {
343  $thisfile_ac3_raw_bsi['panmean2'] = $this->readHeaderBSI(8);
344  $thisfile_ac3_raw_bsi['paninfo2'] = $this->readHeaderBSI(6);
345  }
346  }
347  }
348  $thisfile_ac3_raw_bsi['flags']['frmmixcfginfo'] = (bool) $this->readHeaderBSI(1);
349  if ($thisfile_ac3_raw_bsi['flags']['frmmixcfginfo']) { // mixing configuration information
350  if ($thisfile_ac3_raw_bsi['numblkscod'] == 0) {
351  $thisfile_ac3_raw_bsi['blkmixcfginfo'][0] = $this->readHeaderBSI(5);
352  } else {
353  for ($blk = 0; $blk < $thisfile_ac3_raw_bsi['numblkscod']; $blk++) {
354  $thisfile_ac3_raw_bsi['flags']['blkmixcfginfo'.$blk] = (bool) $this->readHeaderBSI(1);
355  if ($thisfile_ac3_raw_bsi['flags']['blkmixcfginfo'.$blk]) { // mixing configuration information
356  $thisfile_ac3_raw_bsi['blkmixcfginfo'][$blk] = $this->readHeaderBSI(5);
357  }
358  }
359  }
360  }
361  }
362  }
363  $thisfile_ac3_raw_bsi['flags']['infomdat'] = (bool) $this->readHeaderBSI(1);
364  if ($thisfile_ac3_raw_bsi['flags']['infomdat']) { // Informational metadata
365  $thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3);
366  $thisfile_ac3_raw_bsi['flags']['copyrightb'] = (bool) $this->readHeaderBSI(1);
367  $thisfile_ac3_raw_bsi['flags']['origbs'] = (bool) $this->readHeaderBSI(1);
368  if ($thisfile_ac3_raw_bsi['acmod'] == 2) { // if in 2/0 mode
369  $thisfile_ac3_raw_bsi['dsurmod'] = $this->readHeaderBSI(2);
370  $thisfile_ac3_raw_bsi['dheadphonmod'] = $this->readHeaderBSI(2);
371  }
372  if ($thisfile_ac3_raw_bsi['acmod'] >= 6) { // if both surround channels exist
373  $thisfile_ac3_raw_bsi['dsurexmod'] = $this->readHeaderBSI(2);
374  }
375  $thisfile_ac3_raw_bsi['flags']['audprodi'] = (bool) $this->readHeaderBSI(1);
376  if ($thisfile_ac3_raw_bsi['flags']['audprodi']) {
377  $thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5);
378  $thisfile_ac3_raw_bsi['roomtyp'] = $this->readHeaderBSI(2);
379  $thisfile_ac3_raw_bsi['flags']['adconvtyp'] = (bool) $this->readHeaderBSI(1);
380  }
381  if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value)
382  $thisfile_ac3_raw_bsi['flags']['audprodi2'] = (bool) $this->readHeaderBSI(1);
383  if ($thisfile_ac3_raw_bsi['flags']['audprodi2']) {
384  $thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5);
385  $thisfile_ac3_raw_bsi['roomtyp2'] = $this->readHeaderBSI(2);
386  $thisfile_ac3_raw_bsi['flags']['adconvtyp2'] = (bool) $this->readHeaderBSI(1);
387  }
388  }
389  if ($thisfile_ac3_raw_bsi['fscod'] < 3) { // if not half sample rate
390  $thisfile_ac3_raw_bsi['flags']['sourcefscod'] = (bool) $this->readHeaderBSI(1);
391  }
392  }
393  if (($thisfile_ac3_raw_bsi['strmtyp'] == 0) && ($thisfile_ac3_raw_bsi['numblkscod'] != 3)) { // if both surround channels exist
394  $thisfile_ac3_raw_bsi['flags']['convsync'] = (bool) $this->readHeaderBSI(1);
395  }
396  if ($thisfile_ac3_raw_bsi['strmtyp'] == 2) { // if bit stream converted from AC-3
397  if ($thisfile_ac3_raw_bsi['numblkscod'] != 3) { // 6 blocks per syncframe
398  $thisfile_ac3_raw_bsi['flags']['blkid'] = 1;
399  } else {
400  $thisfile_ac3_raw_bsi['flags']['blkid'] = (bool) $this->readHeaderBSI(1);
401  }
402  if ($thisfile_ac3_raw_bsi['flags']['blkid']) {
403  $thisfile_ac3_raw_bsi['frmsizecod'] = $this->readHeaderBSI(6);
404  }
405  }
406  $thisfile_ac3_raw_bsi['flags']['addbsi'] = (bool) $this->readHeaderBSI(1);
407  if ($thisfile_ac3_raw_bsi['flags']['addbsi']) {
408  $thisfile_ac3_raw_bsi['addbsil'] = $this->readHeaderBSI(6);
409  $thisfile_ac3_raw_bsi['addbsi'] = $this->readHeaderBSI(($thisfile_ac3_raw_bsi['addbsil'] + 1) * 8);
410  }
411 
412  } else {
413 
414  $this->error('Bit stream identification is version '.$thisfile_ac3_raw_bsi['bsid'].', but getID3() only understands up to version 16. Please submit a support ticket with a sample file.');
415  unset($info['ac3']);
416  return false;
417 
418  }
419 
420  if (isset($thisfile_ac3_raw_bsi['fscod2'])) {
421  $thisfile_ac3['sample_rate'] = self::sampleRateCodeLookup2($thisfile_ac3_raw_bsi['fscod2']);
422  } else {
423  $thisfile_ac3['sample_rate'] = self::sampleRateCodeLookup($thisfile_ac3_raw_bsi['fscod']);
424  }
425  if ($thisfile_ac3_raw_bsi['fscod'] <= 3) {
426  $info['audio']['sample_rate'] = $thisfile_ac3['sample_rate'];
427  } else {
428  $this->warning('Unexpected ac3.bsi.fscod value: '.$thisfile_ac3_raw_bsi['fscod']);
429  }
430  if (isset($thisfile_ac3_raw_bsi['frmsizecod'])) {
431  $thisfile_ac3['frame_length'] = self::frameSizeLookup($thisfile_ac3_raw_bsi['frmsizecod'], $thisfile_ac3_raw_bsi['fscod']);
432  $thisfile_ac3['bitrate'] = self::bitrateLookup($thisfile_ac3_raw_bsi['frmsizecod']);
433  } elseif (!empty($thisfile_ac3_raw_bsi['frmsiz'])) {
434 // this isn't right, but it's (usually) close, roughly 5% less than it should be.
435 // but WHERE is the actual bitrate value stored in EAC3?? email info@getid3.org if you know!
436  $thisfile_ac3['bitrate'] = ($thisfile_ac3_raw_bsi['frmsiz'] + 1) * 16 * 30; // The frmsiz field shall contain a value one less than the overall size of the coded syncframe in 16-bit words. That is, this field may assume a value ranging from 0 to 2047, and these values correspond to syncframe sizes ranging from 1 to 2048.
437 // kludge-fix to make it approximately the expected value, still not "right":
438 $thisfile_ac3['bitrate'] = round(($thisfile_ac3['bitrate'] * 1.05) / 16000) * 16000;
439  }
440  $info['audio']['bitrate'] = $thisfile_ac3['bitrate'];
441 
442  $thisfile_ac3['service_type'] = self::serviceTypeLookup($thisfile_ac3_raw_bsi['bsmod'], $thisfile_ac3_raw_bsi['acmod']);
443  $ac3_coding_mode = self::audioCodingModeLookup($thisfile_ac3_raw_bsi['acmod']);
444  foreach($ac3_coding_mode as $key => $value) {
445  $thisfile_ac3[$key] = $value;
446  }
447  switch ($thisfile_ac3_raw_bsi['acmod']) {
448  case 0:
449  case 1:
450  $info['audio']['channelmode'] = 'mono';
451  break;
452  case 3:
453  case 4:
454  $info['audio']['channelmode'] = 'stereo';
455  break;
456  default:
457  $info['audio']['channelmode'] = 'surround';
458  break;
459  }
460  $info['audio']['channels'] = $thisfile_ac3['num_channels'];
461 
462  $thisfile_ac3['lfe_enabled'] = $thisfile_ac3_raw_bsi['flags']['lfeon'];
463  if ($thisfile_ac3_raw_bsi['flags']['lfeon']) {
464  $info['audio']['channels'] .= '.1';
465  }
466 
467  $thisfile_ac3['channels_enabled'] = self::channelsEnabledLookup($thisfile_ac3_raw_bsi['acmod'], $thisfile_ac3_raw_bsi['flags']['lfeon']);
468  $thisfile_ac3['dialogue_normalization'] = '-'.$thisfile_ac3_raw_bsi['dialnorm'].'dB';
469 
470  return true;
471  }
472 
473  private function readHeaderBSI($length) {
474  $data = substr($this->AC3header['bsi'], $this->BSIoffset, $length);
475  $this->BSIoffset += $length;
476 
477  return bindec($data);
478  }
479 
480  public static function sampleRateCodeLookup($fscod) {
481  static $sampleRateCodeLookup = array(
482  0 => 48000,
483  1 => 44100,
484  2 => 32000,
485  3 => 'reserved' // If the reserved code is indicated, the decoder should not attempt to decode audio and should mute.
486  );
487  return (isset($sampleRateCodeLookup[$fscod]) ? $sampleRateCodeLookup[$fscod] : false);
488  }
489 
490  public static function sampleRateCodeLookup2($fscod2) {
491  static $sampleRateCodeLookup2 = array(
492  0 => 24000,
493  1 => 22050,
494  2 => 16000,
495  3 => 'reserved' // If the reserved code is indicated, the decoder should not attempt to decode audio and should mute.
496  );
497  return (isset($sampleRateCodeLookup2[$fscod2]) ? $sampleRateCodeLookup2[$fscod2] : false);
498  }
499 
500  public static function serviceTypeLookup($bsmod, $acmod) {
501  static $serviceTypeLookup = array();
502  if (empty($serviceTypeLookup)) {
503  for ($i = 0; $i <= 7; $i++) {
504  $serviceTypeLookup[0][$i] = 'main audio service: complete main (CM)';
505  $serviceTypeLookup[1][$i] = 'main audio service: music and effects (ME)';
506  $serviceTypeLookup[2][$i] = 'associated service: visually impaired (VI)';
507  $serviceTypeLookup[3][$i] = 'associated service: hearing impaired (HI)';
508  $serviceTypeLookup[4][$i] = 'associated service: dialogue (D)';
509  $serviceTypeLookup[5][$i] = 'associated service: commentary (C)';
510  $serviceTypeLookup[6][$i] = 'associated service: emergency (E)';
511  }
512 
513  $serviceTypeLookup[7][1] = 'associated service: voice over (VO)';
514  for ($i = 2; $i <= 7; $i++) {
515  $serviceTypeLookup[7][$i] = 'main audio service: karaoke';
516  }
517  }
518  return (isset($serviceTypeLookup[$bsmod][$acmod]) ? $serviceTypeLookup[$bsmod][$acmod] : false);
519  }
520 
521  public static function audioCodingModeLookup($acmod) {
522  // array(channel configuration, # channels (not incl LFE), channel order)
523  static $audioCodingModeLookup = array (
524  0 => array('channel_config'=>'1+1', 'num_channels'=>2, 'channel_order'=>'Ch1,Ch2'),
525  1 => array('channel_config'=>'1/0', 'num_channels'=>1, 'channel_order'=>'C'),
526  2 => array('channel_config'=>'2/0', 'num_channels'=>2, 'channel_order'=>'L,R'),
527  3 => array('channel_config'=>'3/0', 'num_channels'=>3, 'channel_order'=>'L,C,R'),
528  4 => array('channel_config'=>'2/1', 'num_channels'=>3, 'channel_order'=>'L,R,S'),
529  5 => array('channel_config'=>'3/1', 'num_channels'=>4, 'channel_order'=>'L,C,R,S'),
530  6 => array('channel_config'=>'2/2', 'num_channels'=>4, 'channel_order'=>'L,R,SL,SR'),
531  7 => array('channel_config'=>'3/2', 'num_channels'=>5, 'channel_order'=>'L,C,R,SL,SR'),
532  );
533  return (isset($audioCodingModeLookup[$acmod]) ? $audioCodingModeLookup[$acmod] : false);
534  }
535 
536  public static function centerMixLevelLookup($cmixlev) {
537  static $centerMixLevelLookup;
538  if (empty($centerMixLevelLookup)) {
539  $centerMixLevelLookup = array(
540  0 => pow(2, -3.0 / 6), // 0.707 (-3.0 dB)
541  1 => pow(2, -4.5 / 6), // 0.595 (-4.5 dB)
542  2 => pow(2, -6.0 / 6), // 0.500 (-6.0 dB)
543  3 => 'reserved'
544  );
545  }
546  return (isset($centerMixLevelLookup[$cmixlev]) ? $centerMixLevelLookup[$cmixlev] : false);
547  }
548 
549  public static function surroundMixLevelLookup($surmixlev) {
550  static $surroundMixLevelLookup;
551  if (empty($surroundMixLevelLookup)) {
552  $surroundMixLevelLookup = array(
553  0 => pow(2, -3.0 / 6),
554  1 => pow(2, -6.0 / 6),
555  2 => 0,
556  3 => 'reserved'
557  );
558  }
559  return (isset($surroundMixLevelLookup[$surmixlev]) ? $surroundMixLevelLookup[$surmixlev] : false);
560  }
561 
562  public static function dolbySurroundModeLookup($dsurmod) {
563  static $dolbySurroundModeLookup = array(
564  0 => 'not indicated',
565  1 => 'Not Dolby Surround encoded',
566  2 => 'Dolby Surround encoded',
567  3 => 'reserved'
568  );
569  return (isset($dolbySurroundModeLookup[$dsurmod]) ? $dolbySurroundModeLookup[$dsurmod] : false);
570  }
571 
572  public static function channelsEnabledLookup($acmod, $lfeon) {
573  $lookup = array(
574  'ch1'=>(bool) ($acmod == 0),
575  'ch2'=>(bool) ($acmod == 0),
576  'left'=>(bool) ($acmod > 1),
577  'right'=>(bool) ($acmod > 1),
578  'center'=>(bool) ($acmod & 0x01),
579  'surround_mono'=>false,
580  'surround_left'=>false,
581  'surround_right'=>false,
582  'lfe'=>$lfeon);
583  switch ($acmod) {
584  case 4:
585  case 5:
586  $lookup['surround_mono'] = true;
587  break;
588  case 6:
589  case 7:
590  $lookup['surround_left'] = true;
591  $lookup['surround_right'] = true;
592  break;
593  }
594  return $lookup;
595  }
596 
597  public static function heavyCompression($compre) {
598  // The first four bits indicate gain changes in 6.02dB increments which can be
599  // implemented with an arithmetic shift operation. The following four bits
600  // indicate linear gain changes, and require a 5-bit multiply.
601  // We will represent the two 4-bit fields of compr as follows:
602  // X0 X1 X2 X3 . Y4 Y5 Y6 Y7
603  // The meaning of the X values is most simply described by considering X to represent a 4-bit
604  // signed integer with values from -8 to +7. The gain indicated by X is then (X + 1) * 6.02 dB. The
605  // following table shows this in detail.
606 
607  // Meaning of 4 msb of compr
608  // 7 +48.16 dB
609  // 6 +42.14 dB
610  // 5 +36.12 dB
611  // 4 +30.10 dB
612  // 3 +24.08 dB
613  // 2 +18.06 dB
614  // 1 +12.04 dB
615  // 0 +6.02 dB
616  // -1 0 dB
617  // -2 -6.02 dB
618  // -3 -12.04 dB
619  // -4 -18.06 dB
620  // -5 -24.08 dB
621  // -6 -30.10 dB
622  // -7 -36.12 dB
623  // -8 -42.14 dB
624 
625  $fourbit = str_pad(decbin(($compre & 0xF0) >> 4), 4, '0', STR_PAD_LEFT);
626  if ($fourbit{0} == '1') {
627  $log_gain = -8 + bindec(substr($fourbit, 1));
628  } else {
629  $log_gain = bindec(substr($fourbit, 1));
630  }
631  $log_gain = ($log_gain + 1) * getid3_lib::RGADamplitude2dB(2);
632 
633  // The value of Y is a linear representation of a gain change of up to -6 dB. Y is considered to
634  // be an unsigned fractional integer, with a leading value of 1, or: 0.1 Y4 Y5 Y6 Y7 (base 2). Y can
635  // represent values between 0.111112 (or 31/32) and 0.100002 (or 1/2). Thus, Y can represent gain
636  // changes from -0.28 dB to -6.02 dB.
637 
638  $lin_gain = (16 + ($compre & 0x0F)) / 32;
639 
640  // The combination of X and Y values allows compr to indicate gain changes from
641  // 48.16 - 0.28 = +47.89 dB, to
642  // -42.14 - 6.02 = -48.16 dB.
643 
644  return $log_gain - $lin_gain;
645  }
646 
647  public static function roomTypeLookup($roomtyp) {
648  static $roomTypeLookup = array(
649  0 => 'not indicated',
650  1 => 'large room, X curve monitor',
651  2 => 'small room, flat monitor',
652  3 => 'reserved'
653  );
654  return (isset($roomTypeLookup[$roomtyp]) ? $roomTypeLookup[$roomtyp] : false);
655  }
656 
657  public static function frameSizeLookup($frmsizecod, $fscod) {
658  // LSB is whether padding is used or not
659  $padding = (bool) ($frmsizecod & 0x01);
660  $framesizeid = ($frmsizecod & 0x3E) >> 1;
661 
662  static $frameSizeLookup = array();
663  if (empty($frameSizeLookup)) {
664  $frameSizeLookup = array (
665  0 => array( 128, 138, 192), // 32 kbps
666  1 => array( 160, 174, 240), // 40 kbps
667  2 => array( 192, 208, 288), // 48 kbps
668  3 => array( 224, 242, 336), // 56 kbps
669  4 => array( 256, 278, 384), // 64 kbps
670  5 => array( 320, 348, 480), // 80 kbps
671  6 => array( 384, 416, 576), // 96 kbps
672  7 => array( 448, 486, 672), // 112 kbps
673  8 => array( 512, 556, 768), // 128 kbps
674  9 => array( 640, 696, 960), // 160 kbps
675  10 => array( 768, 834, 1152), // 192 kbps
676  11 => array( 896, 974, 1344), // 224 kbps
677  12 => array(1024, 1114, 1536), // 256 kbps
678  13 => array(1280, 1392, 1920), // 320 kbps
679  14 => array(1536, 1670, 2304), // 384 kbps
680  15 => array(1792, 1950, 2688), // 448 kbps
681  16 => array(2048, 2228, 3072), // 512 kbps
682  17 => array(2304, 2506, 3456), // 576 kbps
683  18 => array(2560, 2786, 3840) // 640 kbps
684  );
685  }
686  if (($fscod == 1) && $padding) {
687  // frame lengths are padded by 1 word (16 bits) at 44100
688  $frameSizeLookup[$frmsizecod] += 2;
689  }
690  return (isset($frameSizeLookup[$framesizeid][$fscod]) ? $frameSizeLookup[$framesizeid][$fscod] : false);
691  }
692 
693  public static function bitrateLookup($frmsizecod) {
694  // LSB is whether padding is used or not
695  $padding = (bool) ($frmsizecod & 0x01);
696  $framesizeid = ($frmsizecod & 0x3E) >> 1;
697 
698  static $bitrateLookup = array(
699  0 => 32000,
700  1 => 40000,
701  2 => 48000,
702  3 => 56000,
703  4 => 64000,
704  5 => 80000,
705  6 => 96000,
706  7 => 112000,
707  8 => 128000,
708  9 => 160000,
709  10 => 192000,
710  11 => 224000,
711  12 => 256000,
712  13 => 320000,
713  14 => 384000,
714  15 => 448000,
715  16 => 512000,
716  17 => 576000,
717  18 => 640000,
718  );
719  return (isset($bitrateLookup[$framesizeid]) ? $bitrateLookup[$framesizeid] : false);
720  }
721 
722  public static function blocksPerSyncFrame($numblkscod) {
723  static $blocksPerSyncFrameLookup = array(
724  0 => 1,
725  1 => 2,
726  2 => 3,
727  3 => 6,
728  );
729  return (isset($blocksPerSyncFrameLookup[$numblkscod]) ? $blocksPerSyncFrameLookup[$numblkscod] : false);
730  }
731 
732 
733 }
getid3_ac3\sampleRateCodeLookup
static sampleRateCodeLookup($fscod)
Definition: module.audio.ac3.php:480
getid3_ac3\surroundMixLevelLookup
static surroundMixLevelLookup($surmixlev)
Definition: module.audio.ac3.php:549
getid3_ac3\$BSIoffset
$BSIoffset
Definition: module.audio.ac3.php:21
getid3_ac3\$AC3header
$AC3header
Definition: module.audio.ac3.php:20
getid3_handler\isDependencyFor
isDependencyFor($module)
Definition: getid3.php:1748
getid3_handler\error
error($text)
Definition: getid3.php:1752
getid3_ac3\serviceTypeLookup
static serviceTypeLookup($bsmod, $acmod)
Definition: module.audio.ac3.php:500
getid3_ac3\readHeaderBSI
readHeaderBSI($length)
Definition: module.audio.ac3.php:473
getid3_ac3\centerMixLevelLookup
static centerMixLevelLookup($cmixlev)
Definition: module.audio.ac3.php:536
getid3_handler\warning
warning($text)
Definition: getid3.php:1758
getid3_ac3\Analyze
Analyze()
Definition: module.audio.ac3.php:25
getid3_lib\Bin2Dec
static Bin2Dec($binstring, $signed=false)
Definition: getid3.lib.php:342
getid3_lib\BigEndian2Bin
static BigEndian2Bin($byteword)
Definition: getid3.lib.php:297
getid3_lib\LittleEndian2Int
static LittleEndian2Int($byteword, $signed=false)
Definition: getid3.lib.php:292
getid3_ac3\roomTypeLookup
static roomTypeLookup($roomtyp)
Definition: module.audio.ac3.php:647
getid3_lib\RGADamplitude2dB
static RGADamplitude2dB($amplitude)
Definition: getid3.lib.php:1174
getid3_ac3\audioCodingModeLookup
static audioCodingModeLookup($acmod)
Definition: module.audio.ac3.php:521
getid3_handler
Definition: getid3.php:1616
getid3_ac3\heavyCompression
static heavyCompression($compre)
Definition: module.audio.ac3.php:597
getid3_ac3\frameSizeLookup
static frameSizeLookup($frmsizecod, $fscod)
Definition: module.audio.ac3.php:657
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1683
getid3_ac3\blocksPerSyncFrame
static blocksPerSyncFrame($numblkscod)
Definition: module.audio.ac3.php:722
getid3_ac3\sampleRateCodeLookup2
static sampleRateCodeLookup2($fscod2)
Definition: module.audio.ac3.php:490
getid3_ac3\bitrateLookup
static bitrateLookup($frmsizecod)
Definition: module.audio.ac3.php:693
$i
$i
Definition: disco.tpl.php:19
getid3_ac3\channelsEnabledLookup
static channelsEnabledLookup($acmod, $lfeon)
Definition: module.audio.ac3.php:572
getid3_ac3\dolbySurroundModeLookup
static dolbySurroundModeLookup($dsurmod)
Definition: module.audio.ac3.php:562
getid3_ac3\syncword
const syncword
Definition: module.audio.ac3.php:23
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1711
$info
$info
Definition: index.php:5
$key
$key
Definition: croninfo.php:18
getid3_lib\BigEndian2Int
static BigEndian2Int($byteword, $synchsafe=false, $signed=false)
Definition: getid3.lib.php:263
getid3_ac3
getID3() by James Heinrich info@getid3.org //
Definition: module.audio.ac3.php:18
$data
$data
Definition: bench.php:6