1<?php
2
3/////////////////////////////////////////////////////////////////
4/// getID3() by James Heinrich <info@getid3.org> //
5// available at https://github.com/JamesHeinrich/getID3 //
6// or https://www.getid3.org //
7// or http://getid3.sourceforge.net //
8// see readme.txt for more details //
9/////////////////////////////////////////////////////////////////
10// //
11// module.audio.dts.php //
12// module for analyzing DTS Audio files //
13// dependencies: NONE //
14// //
15/////////////////////////////////////////////////////////////////
16
17if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
18 exit;
19}
20
21/**
22* @tutorial http://wiki.multimedia.cx/index.php?title=DTS
23*/
24class getid3_dts extends getid3_handler
25{
26 /**
27 * Default DTS syncword used in native .cpt or .dts formats.
28 */
29 const syncword = "\x7F\xFE\x80\x01";
30
31 /**
32 * @var int
33 */
34 private $readBinDataOffset = 0;
35
36 /**
37 * Possible syncwords indicating bitstream encoding.
38 */
39 public static $syncwords = array(
40 0 => "\x7F\xFE\x80\x01", // raw big-endian
41 1 => "\xFE\x7F\x01\x80", // raw little-endian
42 2 => "\x1F\xFF\xE8\x00", // 14-bit big-endian
43 3 => "\xFF\x1F\x00\xE8"); // 14-bit little-endian
44
45 /**
46 * @return bool
47 */
48 public function Analyze() {
49 $info = &$this->getid3->info;
50 $info['fileformat'] = 'dts';
51
52 $this->fseek($info['avdataoffset']);
53 $DTSheader = $this->fread(20); // we only need 2 words magic + 6 words frame header, but these words may be normal 16-bit words OR 14-bit words with 2 highest bits set to zero, so 8 words can be either 8*16/8 = 16 bytes OR 8*16*(16/14)/8 = 18.3 bytes
54
55 // check syncword
56 $sync = substr($DTSheader, 0, 4);
57 if (($encoding = array_search($sync, self::$syncwords)) !== false) {
58
59 $info['dts']['raw']['magic'] = $sync;
60 $this->readBinDataOffset = 32;
61
62 } elseif ($this->isDependencyFor('matroska')) {
63
64 // Matroska contains DTS without syncword encoded as raw big-endian format
65 $encoding = 0;
66 $this->readBinDataOffset = 0;
67
68 } else {
69
70 unset($info['fileformat']);
71 return $this->error('Expecting "'.implode('| ', array_map('getid3_lib::PrintHexBytes', self::$syncwords)).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($sync).'"');
72
73 }
74
75 // decode header
76 $fhBS = '';
77 for ($word_offset = 0; $word_offset <= strlen($DTSheader); $word_offset += 2) {
78 switch ($encoding) {
79 case 0: // raw big-endian
80 $fhBS .= getid3_lib::BigEndian2Bin( substr($DTSheader, $word_offset, 2) );
81 break;
82 case 1: // raw little-endian
83 $fhBS .= getid3_lib::BigEndian2Bin(strrev(substr($DTSheader, $word_offset, 2)));
84 break;
85 case 2: // 14-bit big-endian
86 $fhBS .= substr(getid3_lib::BigEndian2Bin( substr($DTSheader, $word_offset, 2) ), 2, 14);
87 break;
88 case 3: // 14-bit little-endian
89 $fhBS .= substr(getid3_lib::BigEndian2Bin(strrev(substr($DTSheader, $word_offset, 2))), 2, 14);
90 break;
91 }
92 }
93
94 $info['dts']['raw']['frame_type'] = $this->readBinData($fhBS, 1);
95 $info['dts']['raw']['deficit_samples'] = $this->readBinData($fhBS, 5);
96 $info['dts']['flags']['crc_present'] = (bool) $this->readBinData($fhBS, 1);
97 $info['dts']['raw']['pcm_sample_blocks'] = $this->readBinData($fhBS, 7);
98 $info['dts']['raw']['frame_byte_size'] = $this->readBinData($fhBS, 14);
99 $info['dts']['raw']['channel_arrangement'] = $this->readBinData($fhBS, 6);
100 $info['dts']['raw']['sample_frequency'] = $this->readBinData($fhBS, 4);
101 $info['dts']['raw']['bitrate'] = $this->readBinData($fhBS, 5);
102 $info['dts']['flags']['embedded_downmix'] = (bool) $this->readBinData($fhBS, 1);
103 $info['dts']['flags']['dynamicrange'] = (bool) $this->readBinData($fhBS, 1);
104 $info['dts']['flags']['timestamp'] = (bool) $this->readBinData($fhBS, 1);
105 $info['dts']['flags']['auxdata'] = (bool) $this->readBinData($fhBS, 1);
106 $info['dts']['flags']['hdcd'] = (bool) $this->readBinData($fhBS, 1);
107 $info['dts']['raw']['extension_audio'] = $this->readBinData($fhBS, 3);
108 $info['dts']['flags']['extended_coding'] = (bool) $this->readBinData($fhBS, 1);
109 $info['dts']['flags']['audio_sync_insertion'] = (bool) $this->readBinData($fhBS, 1);
110 $info['dts']['raw']['lfe_effects'] = $this->readBinData($fhBS, 2);
111 $info['dts']['flags']['predictor_history'] = (bool) $this->readBinData($fhBS, 1);
112 if ($info['dts']['flags']['crc_present']) {
113 $info['dts']['raw']['crc16'] = $this->readBinData($fhBS, 16);
114 }
115 $info['dts']['flags']['mri_perfect_reconst'] = (bool) $this->readBinData($fhBS, 1);
116 $info['dts']['raw']['encoder_soft_version'] = $this->readBinData($fhBS, 4);
117 $info['dts']['raw']['copy_history'] = $this->readBinData($fhBS, 2);
118 $info['dts']['raw']['bits_per_sample'] = $this->readBinData($fhBS, 2);
119 $info['dts']['flags']['surround_es'] = (bool) $this->readBinData($fhBS, 1);
120 $info['dts']['flags']['front_sum_diff'] = (bool) $this->readBinData($fhBS, 1);
121 $info['dts']['flags']['surround_sum_diff'] = (bool) $this->readBinData($fhBS, 1);
122 $info['dts']['raw']['dialog_normalization'] = $this->readBinData($fhBS, 4);
123
124
125 $info['dts']['bitrate'] = self::bitrateLookup($info['dts']['raw']['bitrate']);
126 $info['dts']['bits_per_sample'] = self::bitPerSampleLookup($info['dts']['raw']['bits_per_sample']);
127 $info['dts']['sample_rate'] = self::sampleRateLookup($info['dts']['raw']['sample_frequency']);
128 $info['dts']['dialog_normalization'] = self::dialogNormalization($info['dts']['raw']['dialog_normalization'], $info['dts']['raw']['encoder_soft_version']);
129 $info['dts']['flags']['lossless'] = (($info['dts']['raw']['bitrate'] == 31) ? true : false);
130 $info['dts']['bitrate_mode'] = (($info['dts']['raw']['bitrate'] == 30) ? 'vbr' : 'cbr');
131 $info['dts']['channels'] = self::numChannelsLookup($info['dts']['raw']['channel_arrangement']);
132 $info['dts']['channel_arrangement'] = self::channelArrangementLookup($info['dts']['raw']['channel_arrangement']);
133
134 $info['audio']['dataformat'] = 'dts';
135 $info['audio']['lossless'] = $info['dts']['flags']['lossless'];
136 $info['audio']['bitrate_mode'] = $info['dts']['bitrate_mode'];
137 $info['audio']['bits_per_sample'] = $info['dts']['bits_per_sample'];
138 $info['audio']['sample_rate'] = $info['dts']['sample_rate'];
139 $info['audio']['channels'] = $info['dts']['channels'];
140 $info['audio']['bitrate'] = $info['dts']['bitrate'];
141 if (isset($info['avdataend']) && !empty($info['dts']['bitrate']) && is_numeric($info['dts']['bitrate'])) {
142 $info['playtime_seconds'] = ($info['avdataend'] - $info['avdataoffset']) / ($info['dts']['bitrate'] / 8);
143 if (($encoding == 2) || ($encoding == 3)) {
144 // 14-bit data packed into 16-bit words, so the playtime is wrong because only (14/16) of the bytes in the data portion of the file are used at the specified bitrate
145 $info['playtime_seconds'] *= (14 / 16);
146 }
147 }
148 return true;
149 }
150
151 /**
152 * @param string $bin
153 * @param int $length
154 *
155 * @return int
156 */
157 private function readBinData($bin, $length) {
158 $data = substr($bin, $this->readBinDataOffset, $length);
159 $this->readBinDataOffset += $length;
160
161 return bindec($data);
162 }
163
164 /**
165 * @param int $index
166 *
167 * @return int|string|false
168 */
169 public static function bitrateLookup($index) {
170 static $lookup = array(
171 0 => 32000,
172 1 => 56000,
173 2 => 64000,
174 3 => 96000,
175 4 => 112000,
176 5 => 128000,
177 6 => 192000,
178 7 => 224000,
179 8 => 256000,
180 9 => 320000,
181 10 => 384000,
182 11 => 448000,
183 12 => 512000,
184 13 => 576000,
185 14 => 640000,
186 15 => 768000,
187 16 => 960000,
188 17 => 1024000,
189 18 => 1152000,
190 19 => 1280000,
191 20 => 1344000,
192 21 => 1408000,
193 22 => 1411200,
194 23 => 1472000,
195 24 => 1536000,
196 25 => 1920000,
197 26 => 2048000,
198 27 => 3072000,
199 28 => 3840000,
200 29 => 'open',
201 30 => 'variable',
202 31 => 'lossless',
203 );
204 return (isset($lookup[$index]) ? $lookup[$index] : false);
205 }
206
207 /**
208 * @param int $index
209 *
210 * @return int|string|false
211 */
212 public static function sampleRateLookup($index) {
213 static $lookup = array(
214 0 => 'invalid',
215 1 => 8000,
216 2 => 16000,
217 3 => 32000,
218 4 => 'invalid',
219 5 => 'invalid',
220 6 => 11025,
221 7 => 22050,
222 8 => 44100,
223 9 => 'invalid',
224 10 => 'invalid',
225 11 => 12000,
226 12 => 24000,
227 13 => 48000,
228 14 => 'invalid',
229 15 => 'invalid',
230 );
231 return (isset($lookup[$index]) ? $lookup[$index] : false);
232 }
233
234 /**
235 * @param int $index
236 *
237 * @return int|false
238 */
239 public static function bitPerSampleLookup($index) {
240 static $lookup = array(
241 0 => 16,
242 1 => 20,
243 2 => 24,
244 3 => 24,
245 );
246 return (isset($lookup[$index]) ? $lookup[$index] : false);
247 }
248
249 /**
250 * @param int $index
251 *
252 * @return int|false
253 */
254 public static function numChannelsLookup($index) {
255 switch ($index) {
256 case 0:
257 return 1;
258 case 1:
259 case 2:
260 case 3:
261 case 4:
262 return 2;
263 case 5:
264 case 6:
265 return 3;
266 case 7:
267 case 8:
268 return 4;
269 case 9:
270 return 5;
271 case 10:
272 case 11:
273 case 12:
274 return 6;
275 case 13:
276 return 7;
277 case 14:
278 case 15:
279 return 8;
280 }
281 return false;
282 }
283
284 /**
285 * @param int $index
286 *
287 * @return string
288 */
289 public static function channelArrangementLookup($index) {
290 static $lookup = array(
291 0 => 'A',
292 1 => 'A + B (dual mono)',
293 2 => 'L + R (stereo)',
294 3 => '(L+R) + (L-R) (sum-difference)',
295 4 => 'LT + RT (left and right total)',
296 5 => 'C + L + R',
297 6 => 'L + R + S',
298 7 => 'C + L + R + S',
299 8 => 'L + R + SL + SR',
300 9 => 'C + L + R + SL + SR',
301 10 => 'CL + CR + L + R + SL + SR',
302 11 => 'C + L + R+ LR + RR + OV',
303 12 => 'CF + CR + LF + RF + LR + RR',
304 13 => 'CL + C + CR + L + R + SL + SR',
305 14 => 'CL + CR + L + R + SL1 + SL2 + SR1 + SR2',
306 15 => 'CL + C+ CR + L + R + SL + S + SR',
307 );
308 return (isset($lookup[$index]) ? $lookup[$index] : 'user-defined');
309 }
310
311 /**
312 * @param int $index
313 * @param int $version
314 *
315 * @return int|false
316 */
317 public static function dialogNormalization($index, $version) {
318 switch ($version) {
319 case 7:
320 return 0 - $index;
321 case 6:
322 return 0 - 16 - $index;
323 }
324 return false;
325 }
326
327}
328