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   1  <?php
   2  /////////////////////////////////////////////////////////////////
   3  /// getID3() by James Heinrich <info@getid3.org>               //
   4  //  available at http://getid3.sourceforge.net                 //
   5  //            or http://www.getid3.org                         //
   6  /////////////////////////////////////////////////////////////////
   7  // See readme.txt for more details                             //
   8  /////////////////////////////////////////////////////////////////
   9  //                                                             //
  10  // module.audio.tta.php                                        //
  11  // module for analyzing TTA Audio files                        //
  12  // dependencies: NONE                                          //
  13  //                                                            ///
  14  /////////////////////////////////////////////////////////////////
  15  
  16  
  17  class getid3_tta
  18  {
  19  
  20  	function getid3_tta(&$fd, &$ThisFileInfo) {
  21  
  22          $ThisFileInfo['fileformat']            = 'tta';
  23          $ThisFileInfo['audio']['dataformat']   = 'tta';
  24          $ThisFileInfo['audio']['lossless']     = true;
  25          $ThisFileInfo['audio']['bitrate_mode'] = 'vbr';
  26  
  27          fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);
  28          $ttaheader = fread($fd, 26);
  29  
  30          $ThisFileInfo['tta']['magic'] = substr($ttaheader,  0,  3);
  31          if ($ThisFileInfo['tta']['magic'] != 'TTA') {
  32              $ThisFileInfo['error'][] = 'Expecting "TTA" at offset '.$ThisFileInfo['avdataoffset'].', found "'.$ThisFileInfo['tta']['magic'].'"';
  33              unset($ThisFileInfo['fileformat']);
  34              unset($ThisFileInfo['audio']);
  35              unset($ThisFileInfo['tta']);
  36              return false;
  37          }
  38  
  39          switch ($ttaheader{3}) {
  40              case "\x01": // TTA v1.x
  41              case "\x02": // TTA v1.x
  42              case "\x03": // TTA v1.x
  43                  // "It was the demo-version of the TTA encoder. There is no released format with such header. TTA encoder v1 is not supported about a year."
  44                  $ThisFileInfo['tta']['major_version'] = 1;
  45                  $ThisFileInfo['avdataoffset'] += 16;
  46  
  47                  $ThisFileInfo['tta']['compression_level']   = ord($ttaheader{3});
  48                  $ThisFileInfo['tta']['channels']            = getid3_lib::LittleEndian2Int(substr($ttaheader,  4,  2));
  49                  $ThisFileInfo['tta']['bits_per_sample']     = getid3_lib::LittleEndian2Int(substr($ttaheader,  6,  2));
  50                  $ThisFileInfo['tta']['sample_rate']         = getid3_lib::LittleEndian2Int(substr($ttaheader,  8,  4));
  51                  $ThisFileInfo['tta']['samples_per_channel'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 12,  4));
  52  
  53                  $ThisFileInfo['audio']['encoder_options']   = '-e'.$ThisFileInfo['tta']['compression_level'];
  54                  $ThisFileInfo['playtime_seconds']           = $ThisFileInfo['tta']['samples_per_channel'] / $ThisFileInfo['tta']['sample_rate'];
  55                  break;
  56  
  57              case '2': // TTA v2.x
  58                  // "I have hurried to release the TTA 2.0 encoder. Format documentation is removed from our site. This format still in development. Please wait the TTA2 format, encoder v4."
  59                  $ThisFileInfo['tta']['major_version'] = 2;
  60                  $ThisFileInfo['avdataoffset'] += 20;
  61  
  62                  $ThisFileInfo['tta']['compression_level']   = getid3_lib::LittleEndian2Int(substr($ttaheader,  4,  2));
  63                  $ThisFileInfo['tta']['audio_format']        = getid3_lib::LittleEndian2Int(substr($ttaheader,  6,  2));
  64                  $ThisFileInfo['tta']['channels']            = getid3_lib::LittleEndian2Int(substr($ttaheader,  8,  2));
  65                  $ThisFileInfo['tta']['bits_per_sample']     = getid3_lib::LittleEndian2Int(substr($ttaheader, 10,  2));
  66                  $ThisFileInfo['tta']['sample_rate']         = getid3_lib::LittleEndian2Int(substr($ttaheader, 12,  4));
  67                  $ThisFileInfo['tta']['data_length']         = getid3_lib::LittleEndian2Int(substr($ttaheader, 16,  4));
  68  
  69                  $ThisFileInfo['audio']['encoder_options']   = '-e'.$ThisFileInfo['tta']['compression_level'];
  70                  $ThisFileInfo['playtime_seconds']           = $ThisFileInfo['tta']['data_length'] / $ThisFileInfo['tta']['sample_rate'];
  71                  break;
  72  
  73              case '1': // TTA v3.x
  74                  // "This is a first stable release of the TTA format. It will be supported by the encoders v3 or higher."
  75                  $ThisFileInfo['tta']['major_version'] = 3;
  76                  $ThisFileInfo['avdataoffset'] += 26;
  77  
  78                  $ThisFileInfo['tta']['audio_format']        = getid3_lib::LittleEndian2Int(substr($ttaheader,  4,  2)); // getid3_riff::RIFFwFormatTagLookup()
  79                  $ThisFileInfo['tta']['channels']            = getid3_lib::LittleEndian2Int(substr($ttaheader,  6,  2));
  80                  $ThisFileInfo['tta']['bits_per_sample']     = getid3_lib::LittleEndian2Int(substr($ttaheader,  8,  2));
  81                  $ThisFileInfo['tta']['sample_rate']         = getid3_lib::LittleEndian2Int(substr($ttaheader, 10,  4));
  82                  $ThisFileInfo['tta']['data_length']         = getid3_lib::LittleEndian2Int(substr($ttaheader, 14,  4));
  83                  $ThisFileInfo['tta']['crc32_footer']        =                              substr($ttaheader, 18,  4);
  84                  $ThisFileInfo['tta']['seek_point']          = getid3_lib::LittleEndian2Int(substr($ttaheader, 22,  4));
  85  
  86                  $ThisFileInfo['playtime_seconds']           = $ThisFileInfo['tta']['data_length'] / $ThisFileInfo['tta']['sample_rate'];
  87                  break;
  88  
  89              default:
  90                  $ThisFileInfo['error'][] = 'This version of getID3() only knows how to handle TTA v1 and v2 - it may not work correctly with this file which appears to be TTA v'.$ttaheader{3};
  91                  return false;
  92                  break;
  93          }
  94  
  95          $ThisFileInfo['audio']['encoder']         = 'TTA v'.$ThisFileInfo['tta']['major_version'];
  96          $ThisFileInfo['audio']['bits_per_sample'] = $ThisFileInfo['tta']['bits_per_sample'];
  97          $ThisFileInfo['audio']['sample_rate']     = $ThisFileInfo['tta']['sample_rate'];
  98          $ThisFileInfo['audio']['channels']        = $ThisFileInfo['tta']['channels'];
  99          $ThisFileInfo['audio']['bitrate']         = (($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) * 8) / $ThisFileInfo['playtime_seconds'];
 100  
 101          return true;
 102      }
 103  
 104  }
 105  
 106  
 107  ?>