name : module.audio.avr.php <?php ///////////////////////////////////////////////////////////////// /// getID3() by James Heinrich <info@getid3.org> // // available at https://github.com/JamesHeinrich/getID3 // // or https://www.getid3.org // // or http://getid3.sourceforge.net // // see readme.txt for more details // ///////////////////////////////////////////////////////////////// // // // module.audio.avr.php // // module for analyzing AVR Audio files // // dependencies: NONE // // /// ///////////////////////////////////////////////////////////////// if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers exit; } class getid3_avr extends getid3_handler { /** * @return bool */ public function Analyze() { $info = &$this->getid3->info; // http://cui.unige.ch/OSG/info/AudioFormats/ap11.html // http://www.btinternet.com/~AnthonyJ/Atari/programming/avr_format.html // offset type length name comments // --------------------------------------------------------------------- // 0 char 4 ID format ID == "2BIT" // 4 char 8 name sample name (unused space filled with 0) // 12 short 1 mono/stereo 0=mono, -1 (0xFFFF)=stereo // With stereo, samples are alternated, // the first voice is the left : // (LRLRLRLRLRLRLRLRLR...) // 14 short 1 resolution 8, 12 or 16 (bits) // 16 short 1 signed or not 0=unsigned, -1 (0xFFFF)=signed // 18 short 1 loop or not 0=no loop, -1 (0xFFFF)=loop on // 20 short 1 MIDI note 0xFFnn, where 0 <= nn <= 127 // 0xFFFF means "no MIDI note defined" // 22 byte 1 Replay speed Frequence in the Replay software // 0=5.485 Khz, 1=8.084 Khz, 2=10.971 Khz, // 3=16.168 Khz, 4=21.942 Khz, 5=32.336 Khz // 6=43.885 Khz, 7=47.261 Khz // -1 (0xFF)=no defined Frequence // 23 byte 3 sample rate in Hertz // 26 long 1 size in bytes (2 * bytes in stereo) // 30 long 1 loop begin 0 for no loop // 34 long 1 loop size equal to 'size' for no loop // 38 short 2 Reserved, MIDI keyboard split */ // 40 short 2 Reserved, sample compression */ // 42 short 2 Reserved */ // 44 char 20; Additional filename space, used if (name[7] != 0) // 64 byte 64 user data // 128 bytes ? sample data (12 bits samples are coded on 16 bits: // 0000 xxxx xxxx xxxx) // --------------------------------------------------------------------- // Note that all values are in motorola (big-endian) format, and that long is // assumed to be 4 bytes, and short 2 bytes. // When reading the samples, you should handle both signed and unsigned data, // and be prepared to convert 16->8 bit, or mono->stereo if needed. To convert // 8-bit data between signed/unsigned just add 127 to the sample values. // Simularly for 16-bit data you should add 32769 $info['fileformat'] = 'avr'; $this->fseek($info['avdataoffset']); $AVRheader = $this->fread(128); $info['avr']['raw']['magic'] = substr($AVRheader, 0, 4); $magic = '2BIT'; if ($info['avr']['raw']['magic'] != $magic) { $this->error('Expecting "'.getid3_lib::PrintHexBytes($magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($info['avr']['raw']['magic']).'"'); unset($info['fileformat']); unset($info['avr']); return false; } $info['avdataoffset'] += 128; $info['avr']['sample_name'] = rtrim(substr($AVRheader, 4, 8)); $info['avr']['raw']['mono'] = getid3_lib::BigEndian2Int(substr($AVRheader, 12, 2)); $info['avr']['bits_per_sample'] = getid3_lib::BigEndian2Int(substr($AVRheader, 14, 2)); $info['avr']['raw']['signed'] = getid3_lib::BigEndian2Int(substr($AVRheader, 16, 2)); $info['avr']['raw']['loop'] = getid3_lib::BigEndian2Int(substr($AVRheader, 18, 2)); $info['avr']['raw']['midi'] = getid3_lib::BigEndian2Int(substr($AVRheader, 20, 2)); $info['avr']['raw']['replay_freq'] = getid3_lib::BigEndian2Int(substr($AVRheader, 22, 1)); $info['avr']['sample_rate'] = getid3_lib::BigEndian2Int(substr($AVRheader, 23, 3)); $info['avr']['sample_length'] = getid3_lib::BigEndian2Int(substr($AVRheader, 26, 4)); $info['avr']['loop_start'] = getid3_lib::BigEndian2Int(substr($AVRheader, 30, 4)); $info['avr']['loop_end'] = getid3_lib::BigEndian2Int(substr($AVRheader, 34, 4)); $info['avr']['midi_split'] = getid3_lib::BigEndian2Int(substr($AVRheader, 38, 2)); $info['avr']['sample_compression'] = getid3_lib::BigEndian2Int(substr($AVRheader, 40, 2)); $info['avr']['reserved'] = getid3_lib::BigEndian2Int(substr($AVRheader, 42, 2)); $info['avr']['sample_name_extra'] = rtrim(substr($AVRheader, 44, 20)); $info['avr']['comment'] = rtrim(substr($AVRheader, 64, 64)); $info['avr']['flags']['stereo'] = (($info['avr']['raw']['mono'] == 0) ? false : true); $info['avr']['flags']['signed'] = (($info['avr']['raw']['signed'] == 0) ? false : true); $info['avr']['flags']['loop'] = (($info['avr']['raw']['loop'] == 0) ? false : true); $info['avr']['midi_notes'] = array(); if (($info['avr']['raw']['midi'] & 0xFF00) != 0xFF00) { $info['avr']['midi_notes'][] = ($info['avr']['raw']['midi'] & 0xFF00) >> 8; } if (($info['avr']['raw']['midi'] & 0x00FF) != 0x00FF) { $info['avr']['midi_notes'][] = ($info['avr']['raw']['midi'] & 0x00FF); } if (($info['avdataend'] - $info['avdataoffset']) != ($info['avr']['sample_length'] * (($info['avr']['bits_per_sample'] == 8) ? 1 : 2))) { $this->warning('Probable truncated file: expecting '.($info['avr']['sample_length'] * (($info['avr']['bits_per_sample'] == 8) ? 1 : 2)).' bytes of audio data, found '.($info['avdataend'] - $info['avdataoffset'])); } $info['audio']['dataformat'] = 'avr'; $info['audio']['lossless'] = true; $info['audio']['bitrate_mode'] = 'cbr'; $info['audio']['bits_per_sample'] = $info['avr']['bits_per_sample']; $info['audio']['sample_rate'] = $info['avr']['sample_rate']; $info['audio']['channels'] = ($info['avr']['flags']['stereo'] ? 2 : 1); $bits_per_sample = ($info['avr']['bits_per_sample'] == 8) ? 8 : 16; $info['audio']['bitrate'] = $bits_per_sample * $info['audio']['channels'] * $info['avr']['sample_rate']; $info['playtime_seconds'] = getid3_lib::SafeDiv($info['avr']['sample_length'] * $bits_per_sample, $info['audio']['bitrate']); return true; } }