File indexing completed on 2024-12-22 05:33:12

0001 <?php
0002 /////////////////////////////////////////////////////////////////
0003 /// getID3() by James Heinrich <info@getid3.org>               //
0004 //  available at http://getid3.sourceforge.net                 //
0005 //            or http://www.getid3.org                         //
0006 //          also https://github.com/JamesHeinrich/getID3       //
0007 /////////////////////////////////////////////////////////////////
0008 // See readme.txt for more details                             //
0009 /////////////////////////////////////////////////////////////////
0010 //                                                             //
0011 // module.audio.dts.php                                        //
0012 // module for analyzing DTS Audio files                        //
0013 // dependencies: NONE                                          //
0014 //                                                             //
0015 /////////////////////////////////////////////////////////////////
0016 
0017 
0018 /**
0019 * @tutorial http://wiki.multimedia.cx/index.php?title=DTS
0020 */
0021 class getid3_dts extends getid3_handler
0022 {
0023   /**
0024   * Default DTS syncword used in native .cpt or .dts formats
0025   */
0026     const syncword = "\x7F\xFE\x80\x01";
0027 
0028   private $readBinDataOffset = 0;
0029 
0030     /**
0031     * Possible syncwords indicating bitstream encoding
0032     */
0033     public static $syncwords = array(
0034       0 => "\x7F\xFE\x80\x01",  // raw big-endian
0035       1 => "\xFE\x7F\x01\x80",  // raw little-endian
0036       2 => "\x1F\xFF\xE8\x00",  // 14-bit big-endian
0037       3 => "\xFF\x1F\x00\xE8"); // 14-bit little-endian
0038 
0039   public function Analyze() {
0040     $info = &$this->getid3->info;
0041     $info['fileformat'] = 'dts';
0042 
0043     $this->fseek($info['avdataoffset']);
0044     $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
0045 
0046     // check syncword
0047     $sync = substr($DTSheader, 0, 4);
0048         if (($encoding = array_search($sync, self::$syncwords)) !== false) {
0049 
0050           $info['dts']['raw']['magic'] = $sync;
0051       $this->readBinDataOffset = 32;
0052 
0053         } elseif ($this->isDependencyFor('matroska')) {
0054 
0055       // Matroska contains DTS without syncword encoded as raw big-endian format
0056       $encoding = 0;
0057       $this->readBinDataOffset = 0;
0058 
0059         } else {
0060 
0061       unset($info['fileformat']);
0062       return $this->error('Expecting "'.implode('| ', array_map('getid3_lib::PrintHexBytes', self::$syncwords)).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($sync).'"');
0063 
0064     }
0065 
0066     // decode header
0067     $fhBS = '';
0068     for ($word_offset = 0; $word_offset <= strlen($DTSheader); $word_offset += 2) {
0069       switch ($encoding) {
0070         case 0: // raw big-endian
0071           $fhBS .=        getid3_lib::BigEndian2Bin(       substr($DTSheader, $word_offset, 2) );
0072           break;
0073         case 1: // raw little-endian
0074           $fhBS .=        getid3_lib::BigEndian2Bin(strrev(substr($DTSheader, $word_offset, 2)));
0075           break;
0076         case 2: // 14-bit big-endian
0077           $fhBS .= substr(getid3_lib::BigEndian2Bin(       substr($DTSheader, $word_offset, 2) ), 2, 14);
0078           break;
0079         case 3: // 14-bit little-endian
0080           $fhBS .= substr(getid3_lib::BigEndian2Bin(strrev(substr($DTSheader, $word_offset, 2))), 2, 14);
0081           break;
0082       }
0083     }
0084 
0085     $info['dts']['raw']['frame_type']             =        $this->readBinData($fhBS,  1);
0086     $info['dts']['raw']['deficit_samples']        =        $this->readBinData($fhBS,  5);
0087     $info['dts']['flags']['crc_present']          = (bool) $this->readBinData($fhBS,  1);
0088     $info['dts']['raw']['pcm_sample_blocks']      =        $this->readBinData($fhBS,  7);
0089     $info['dts']['raw']['frame_byte_size']        =        $this->readBinData($fhBS, 14);
0090     $info['dts']['raw']['channel_arrangement']    =        $this->readBinData($fhBS,  6);
0091     $info['dts']['raw']['sample_frequency']       =        $this->readBinData($fhBS,  4);
0092     $info['dts']['raw']['bitrate']                =        $this->readBinData($fhBS,  5);
0093     $info['dts']['flags']['embedded_downmix']     = (bool) $this->readBinData($fhBS,  1);
0094     $info['dts']['flags']['dynamicrange']         = (bool) $this->readBinData($fhBS,  1);
0095     $info['dts']['flags']['timestamp']            = (bool) $this->readBinData($fhBS,  1);
0096     $info['dts']['flags']['auxdata']              = (bool) $this->readBinData($fhBS,  1);
0097     $info['dts']['flags']['hdcd']                 = (bool) $this->readBinData($fhBS,  1);
0098     $info['dts']['raw']['extension_audio']        =        $this->readBinData($fhBS,  3);
0099     $info['dts']['flags']['extended_coding']      = (bool) $this->readBinData($fhBS,  1);
0100     $info['dts']['flags']['audio_sync_insertion'] = (bool) $this->readBinData($fhBS,  1);
0101     $info['dts']['raw']['lfe_effects']            =        $this->readBinData($fhBS,  2);
0102     $info['dts']['flags']['predictor_history']    = (bool) $this->readBinData($fhBS,  1);
0103     if ($info['dts']['flags']['crc_present']) {
0104       $info['dts']['raw']['crc16']              =        $this->readBinData($fhBS, 16);
0105     }
0106     $info['dts']['flags']['mri_perfect_reconst']  = (bool) $this->readBinData($fhBS,  1);
0107     $info['dts']['raw']['encoder_soft_version']   =        $this->readBinData($fhBS,  4);
0108     $info['dts']['raw']['copy_history']           =        $this->readBinData($fhBS,  2);
0109     $info['dts']['raw']['bits_per_sample']        =        $this->readBinData($fhBS,  2);
0110     $info['dts']['flags']['surround_es']          = (bool) $this->readBinData($fhBS,  1);
0111     $info['dts']['flags']['front_sum_diff']       = (bool) $this->readBinData($fhBS,  1);
0112     $info['dts']['flags']['surround_sum_diff']    = (bool) $this->readBinData($fhBS,  1);
0113     $info['dts']['raw']['dialog_normalization']   =        $this->readBinData($fhBS,  4);
0114 
0115 
0116     $info['dts']['bitrate']              = self::bitrateLookup($info['dts']['raw']['bitrate']);
0117     $info['dts']['bits_per_sample']      = self::bitPerSampleLookup($info['dts']['raw']['bits_per_sample']);
0118     $info['dts']['sample_rate']          = self::sampleRateLookup($info['dts']['raw']['sample_frequency']);
0119     $info['dts']['dialog_normalization'] = self::dialogNormalization($info['dts']['raw']['dialog_normalization'], $info['dts']['raw']['encoder_soft_version']);
0120     $info['dts']['flags']['lossless']    = (($info['dts']['raw']['bitrate'] == 31) ? true  : false);
0121     $info['dts']['bitrate_mode']         = (($info['dts']['raw']['bitrate'] == 30) ? 'vbr' : 'cbr');
0122     $info['dts']['channels']             = self::numChannelsLookup($info['dts']['raw']['channel_arrangement']);
0123     $info['dts']['channel_arrangement']  = self::channelArrangementLookup($info['dts']['raw']['channel_arrangement']);
0124 
0125     $info['audio']['dataformat']          = 'dts';
0126     $info['audio']['lossless']            = $info['dts']['flags']['lossless'];
0127     $info['audio']['bitrate_mode']        = $info['dts']['bitrate_mode'];
0128     $info['audio']['bits_per_sample']     = $info['dts']['bits_per_sample'];
0129     $info['audio']['sample_rate']         = $info['dts']['sample_rate'];
0130     $info['audio']['channels']            = $info['dts']['channels'];
0131     $info['audio']['bitrate']             = $info['dts']['bitrate'];
0132     if (isset($info['avdataend']) && !empty($info['dts']['bitrate']) && is_numeric($info['dts']['bitrate'])) {
0133       $info['playtime_seconds']         = ($info['avdataend'] - $info['avdataoffset']) / ($info['dts']['bitrate'] / 8);
0134       if (($encoding == 2) || ($encoding == 3)) {
0135         // 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
0136         $info['playtime_seconds'] *= (14 / 16);
0137       }
0138     }
0139     return true;
0140   }
0141 
0142   private function readBinData($bin, $length) {
0143     $data = substr($bin, $this->readBinDataOffset, $length);
0144     $this->readBinDataOffset += $length;
0145 
0146     return bindec($data);
0147   }
0148 
0149   public static function bitrateLookup($index) {
0150     static $lookup = array(
0151       0  => 32000,
0152       1  => 56000,
0153       2  => 64000,
0154       3  => 96000,
0155       4  => 112000,
0156       5  => 128000,
0157       6  => 192000,
0158       7  => 224000,
0159       8  => 256000,
0160       9  => 320000,
0161       10 => 384000,
0162       11 => 448000,
0163       12 => 512000,
0164       13 => 576000,
0165       14 => 640000,
0166       15 => 768000,
0167       16 => 960000,
0168       17 => 1024000,
0169       18 => 1152000,
0170       19 => 1280000,
0171       20 => 1344000,
0172       21 => 1408000,
0173       22 => 1411200,
0174       23 => 1472000,
0175       24 => 1536000,
0176       25 => 1920000,
0177       26 => 2048000,
0178       27 => 3072000,
0179       28 => 3840000,
0180       29 => 'open',
0181       30 => 'variable',
0182       31 => 'lossless',
0183     );
0184     return (isset($lookup[$index]) ? $lookup[$index] : false);
0185   }
0186 
0187   public static function sampleRateLookup($index) {
0188     static $lookup = array(
0189       0  => 'invalid',
0190       1  => 8000,
0191       2  => 16000,
0192       3  => 32000,
0193       4  => 'invalid',
0194       5  => 'invalid',
0195       6  => 11025,
0196       7  => 22050,
0197       8  => 44100,
0198       9  => 'invalid',
0199       10 => 'invalid',
0200       11 => 12000,
0201       12 => 24000,
0202       13 => 48000,
0203       14 => 'invalid',
0204       15 => 'invalid',
0205     );
0206     return (isset($lookup[$index]) ? $lookup[$index] : false);
0207   }
0208 
0209   public static function bitPerSampleLookup($index) {
0210     static $lookup = array(
0211       0  => 16,
0212       1  => 20,
0213       2  => 24,
0214       3  => 24,
0215     );
0216     return (isset($lookup[$index]) ? $lookup[$index] : false);
0217   }
0218 
0219   public static function numChannelsLookup($index) {
0220     switch ($index) {
0221       case 0:
0222         return 1;
0223         break;
0224       case 1:
0225       case 2:
0226       case 3:
0227       case 4:
0228         return 2;
0229         break;
0230       case 5:
0231       case 6:
0232         return 3;
0233         break;
0234       case 7:
0235       case 8:
0236         return 4;
0237         break;
0238       case 9:
0239         return 5;
0240         break;
0241       case 10:
0242       case 11:
0243       case 12:
0244         return 6;
0245         break;
0246       case 13:
0247         return 7;
0248         break;
0249       case 14:
0250       case 15:
0251         return 8;
0252         break;
0253     }
0254     return false;
0255   }
0256 
0257   public static function channelArrangementLookup($index) {
0258     static $lookup = array(
0259       0  => 'A',
0260       1  => 'A + B (dual mono)',
0261       2  => 'L + R (stereo)',
0262       3  => '(L+R) + (L-R) (sum-difference)',
0263       4  => 'LT + RT (left and right total)',
0264       5  => 'C + L + R',
0265       6  => 'L + R + S',
0266       7  => 'C + L + R + S',
0267       8  => 'L + R + SL + SR',
0268       9  => 'C + L + R + SL + SR',
0269       10 => 'CL + CR + L + R + SL + SR',
0270       11 => 'C + L + R+ LR + RR + OV',
0271       12 => 'CF + CR + LF + RF + LR + RR',
0272       13 => 'CL + C + CR + L + R + SL + SR',
0273       14 => 'CL + CR + L + R + SL1 + SL2 + SR1 + SR2',
0274       15 => 'CL + C+ CR + L + R + SL + S + SR',
0275     );
0276     return (isset($lookup[$index]) ? $lookup[$index] : 'user-defined');
0277   }
0278 
0279   public static function dialogNormalization($index, $version) {
0280     switch ($version) {
0281       case 7:
0282         return 0 - $index;
0283         break;
0284       case 6:
0285         return 0 - 16 - $index;
0286         break;
0287     }
0288     return false;
0289   }
0290 
0291 }