www/plugins-dist/medias/lib/getid3/module.audio.avr.php

   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.avr.php                                        //
  12 // module for analyzing AVR Audio files                        //
  13 // dependencies: NONE                                          //
  14 //                                                            ///
  15 /////////////////////////////////////////////////////////////////
  16
  17
  18 class getid3_avr extends getid3_handler
  19 {
  20         /**
  21          * @return bool
  22          */
  23         public function Analyze() {
  24                 $info = &$this->getid3->info;
  25
  26                 // http://cui.unige.ch/OSG/info/AudioFormats/ap11.html
  27                 // http://www.btinternet.com/~AnthonyJ/Atari/programming/avr_format.html
  28                 // offset    type    length    name        comments
  29                 // ---------------------------------------------------------------------
  30                 // 0    char    4    ID        format ID == "2BIT"
  31                 // 4    char    8    name        sample name (unused space filled with 0)
  32                 // 12    short    1    mono/stereo    0=mono, -1 (0xFFFF)=stereo
  33                 //                     With stereo, samples are alternated,
  34                 //                     the first voice is the left :
  35                 //                     (LRLRLRLRLRLRLRLRLR...)
  36                 // 14    short    1    resolution    8, 12 or 16 (bits)
  37                 // 16    short    1    signed or not    0=unsigned, -1 (0xFFFF)=signed
  38                 // 18    short    1    loop or not    0=no loop, -1 (0xFFFF)=loop on
  39                 // 20    short    1    MIDI note    0xFFnn, where 0 <= nn <= 127
  40                 //                     0xFFFF means "no MIDI note defined"
  41                 // 22    byte    1    Replay speed    Frequence in the Replay software
  42                 //                     0=5.485 Khz, 1=8.084 Khz, 2=10.971 Khz,
  43                 //                     3=16.168 Khz, 4=21.942 Khz, 5=32.336 Khz
  44                 //                     6=43.885 Khz, 7=47.261 Khz
  45                 //                     -1 (0xFF)=no defined Frequence
  46                 // 23    byte    3    sample rate    in Hertz
  47                 // 26    long    1    size in bytes (2 * bytes in stereo)
  48                 // 30    long    1    loop begin    0 for no loop
  49                 // 34    long    1    loop size    equal to 'size' for no loop
  50                 // 38  short   2   Reserved, MIDI keyboard split */
  51                 // 40  short   2   Reserved, sample compression */
  52                 // 42  short   2   Reserved */
  53                 // 44  char   20;  Additional filename space, used if (name[7] != 0)
  54                 // 64    byte    64    user data
  55                 // 128    bytes    ?    sample data    (12 bits samples are coded on 16 bits:
  56                 //                     0000 xxxx xxxx xxxx)
  57                 // ---------------------------------------------------------------------
  58
  59                 // Note that all values are in motorola (big-endian) format, and that long is
  60                 // assumed to be 4 bytes, and short 2 bytes.
  61                 // When reading the samples, you should handle both signed and unsigned data,
  62                 // and be prepared to convert 16->8 bit, or mono->stereo if needed. To convert
  63                 // 8-bit data between signed/unsigned just add 127 to the sample values.
  64                 // Simularly for 16-bit data you should add 32769
  65
  66                 $info['fileformat'] = 'avr';
  67
  68                 $this->fseek($info['avdataoffset']);
  69                 $AVRheader = $this->fread(128);
  70
  71                 $info['avr']['raw']['magic'] = substr($AVRheader,  0,  4);
  72                 $magic = '2BIT';
  73                 if ($info['avr']['raw']['magic'] != $magic) {
  74                         $this->error('Expecting "'.getid3_lib::PrintHexBytes($magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($info['avr']['raw']['magic']).'"');
  75                         unset($info['fileformat']);
  76                         unset($info['avr']);
  77                         return false;
  78                 }
  79                 $info['avdataoffset'] += 128;
  80
  81                 $info['avr']['sample_name']        =         rtrim(substr($AVRheader,  4,  8));
  82                 $info['avr']['raw']['mono']        = getid3_lib::BigEndian2Int(substr($AVRheader, 12,  2));
  83                 $info['avr']['bits_per_sample']    = getid3_lib::BigEndian2Int(substr($AVRheader, 14,  2));
  84                 $info['avr']['raw']['signed']      = getid3_lib::BigEndian2Int(substr($AVRheader, 16,  2));
  85                 $info['avr']['raw']['loop']        = getid3_lib::BigEndian2Int(substr($AVRheader, 18,  2));
  86                 $info['avr']['raw']['midi']        = getid3_lib::BigEndian2Int(substr($AVRheader, 20,  2));
  87                 $info['avr']['raw']['replay_freq'] = getid3_lib::BigEndian2Int(substr($AVRheader, 22,  1));
  88                 $info['avr']['sample_rate']        = getid3_lib::BigEndian2Int(substr($AVRheader, 23,  3));
  89                 $info['avr']['sample_length']      = getid3_lib::BigEndian2Int(substr($AVRheader, 26,  4));
  90                 $info['avr']['loop_start']         = getid3_lib::BigEndian2Int(substr($AVRheader, 30,  4));
  91                 $info['avr']['loop_end']           = getid3_lib::BigEndian2Int(substr($AVRheader, 34,  4));
  92                 $info['avr']['midi_split']         = getid3_lib::BigEndian2Int(substr($AVRheader, 38,  2));
  93                 $info['avr']['sample_compression'] = getid3_lib::BigEndian2Int(substr($AVRheader, 40,  2));
  94                 $info['avr']['reserved']           = getid3_lib::BigEndian2Int(substr($AVRheader, 42,  2));
  95                 $info['avr']['sample_name_extra']  =         rtrim(substr($AVRheader, 44, 20));
  96                 $info['avr']['comment']            =         rtrim(substr($AVRheader, 64, 64));
  97
  98                 $info['avr']['flags']['stereo'] = (($info['avr']['raw']['mono']   == 0) ? false : true);
  99                 $info['avr']['flags']['signed'] = (($info['avr']['raw']['signed'] == 0) ? false : true);
 100                 $info['avr']['flags']['loop']   = (($info['avr']['raw']['loop']   == 0) ? false : true);
 101
 102                 $info['avr']['midi_notes'] = array();
 103                 if (($info['avr']['raw']['midi'] & 0xFF00) != 0xFF00) {
 104                         $info['avr']['midi_notes'][] = ($info['avr']['raw']['midi'] & 0xFF00) >> 8;
 105                 }
 106                 if (($info['avr']['raw']['midi'] & 0x00FF) != 0x00FF) {
 107                         $info['avr']['midi_notes'][] = ($info['avr']['raw']['midi'] & 0x00FF);
 108                 }
 109
 110                 if (($info['avdataend'] - $info['avdataoffset']) != ($info['avr']['sample_length'] * (($info['avr']['bits_per_sample'] == 8) ? 1 : 2))) {
 111                         $this->warning('Probable truncated file: expecting '.($info['avr']['sample_length'] * (($info['avr']['bits_per_sample'] == 8) ? 1 : 2)).' bytes of audio data, found '.($info['avdataend'] - $info['avdataoffset']));
 112                 }
 113
 114                 $info['audio']['dataformat']      = 'avr';
 115                 $info['audio']['lossless']        = true;
 116                 $info['audio']['bitrate_mode']    = 'cbr';
 117                 $info['audio']['bits_per_sample'] = $info['avr']['bits_per_sample'];
 118                 $info['audio']['sample_rate']     = $info['avr']['sample_rate'];
 119                 $info['audio']['channels']        = ($info['avr']['flags']['stereo'] ? 2 : 1);
 120                 $info['playtime_seconds']         = ($info['avr']['sample_length'] / $info['audio']['channels']) / $info['avr']['sample_rate'];
 121                 $info['audio']['bitrate']         = ($info['avr']['sample_length'] * (($info['avr']['bits_per_sample'] == 8) ? 8 : 16)) / $info['playtime_seconds'];
 122
 123
 124                 return true;
 125         }
 126
 127 }