File indexing completed on 2024-05-12 05:58:13
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.lpac.php // 0012 // module for analyzing LPAC Audio files // 0013 // dependencies: module.audio-video.riff.php // 0014 // /// 0015 ///////////////////////////////////////////////////////////////// 0016 0017 getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true); 0018 0019 class getid3_lpac extends getid3_handler 0020 { 0021 0022 public function Analyze() { 0023 $info = &$this->getid3->info; 0024 0025 $this->fseek($info['avdataoffset']); 0026 $LPACheader = $this->fread(14); 0027 if (substr($LPACheader, 0, 4) != 'LPAC') { 0028 $info['error'][] = 'Expected "LPAC" at offset '.$info['avdataoffset'].', found "'.$StreamMarker.'"'; 0029 return false; 0030 } 0031 $info['avdataoffset'] += 14; 0032 0033 $info['fileformat'] = 'lpac'; 0034 $info['audio']['dataformat'] = 'lpac'; 0035 $info['audio']['lossless'] = true; 0036 $info['audio']['bitrate_mode'] = 'vbr'; 0037 0038 $info['lpac']['file_version'] = getid3_lib::BigEndian2Int(substr($LPACheader, 4, 1)); 0039 $flags['audio_type'] = getid3_lib::BigEndian2Int(substr($LPACheader, 5, 1)); 0040 $info['lpac']['total_samples']= getid3_lib::BigEndian2Int(substr($LPACheader, 6, 4)); 0041 $flags['parameters'] = getid3_lib::BigEndian2Int(substr($LPACheader, 10, 4)); 0042 0043 $info['lpac']['flags']['is_wave'] = (bool) ($flags['audio_type'] & 0x40); 0044 $info['lpac']['flags']['stereo'] = (bool) ($flags['audio_type'] & 0x04); 0045 $info['lpac']['flags']['24_bit'] = (bool) ($flags['audio_type'] & 0x02); 0046 $info['lpac']['flags']['16_bit'] = (bool) ($flags['audio_type'] & 0x01); 0047 0048 if ($info['lpac']['flags']['24_bit'] && $info['lpac']['flags']['16_bit']) { 0049 $info['warning'][] = '24-bit and 16-bit flags cannot both be set'; 0050 } 0051 0052 $info['lpac']['flags']['fast_compress'] = (bool) ($flags['parameters'] & 0x40000000); 0053 $info['lpac']['flags']['random_access'] = (bool) ($flags['parameters'] & 0x08000000); 0054 $info['lpac']['block_length'] = pow(2, (($flags['parameters'] & 0x07000000) >> 24)) * 256; 0055 $info['lpac']['flags']['adaptive_prediction_order'] = (bool) ($flags['parameters'] & 0x00800000); 0056 $info['lpac']['flags']['adaptive_quantization'] = (bool) ($flags['parameters'] & 0x00400000); 0057 $info['lpac']['flags']['joint_stereo'] = (bool) ($flags['parameters'] & 0x00040000); 0058 $info['lpac']['quantization'] = ($flags['parameters'] & 0x00001F00) >> 8; 0059 $info['lpac']['max_prediction_order'] = ($flags['parameters'] & 0x0000003F); 0060 0061 if ($info['lpac']['flags']['fast_compress'] && ($info['lpac']['max_prediction_order'] != 3)) { 0062 $info['warning'][] = 'max_prediction_order expected to be "3" if fast_compress is true, actual value is "'.$info['lpac']['max_prediction_order'].'"'; 0063 } 0064 switch ($info['lpac']['file_version']) { 0065 case 6: 0066 if ($info['lpac']['flags']['adaptive_quantization']) { 0067 $info['warning'][] = 'adaptive_quantization expected to be false in LPAC file stucture v6, actually true'; 0068 } 0069 if ($info['lpac']['quantization'] != 20) { 0070 $info['warning'][] = 'Quantization expected to be 20 in LPAC file stucture v6, actually '.$info['lpac']['flags']['Q']; 0071 } 0072 break; 0073 0074 default: 0075 //$info['warning'][] = 'This version of getID3() ['.$this->getid3->version().'] only supports LPAC file format version 6, this file is version '.$info['lpac']['file_version'].' - please report to info@getid3.org'; 0076 break; 0077 } 0078 0079 $getid3_temp = new getID3(); 0080 $getid3_temp->openfile($this->getid3->filename); 0081 $getid3_temp->info = $info; 0082 $getid3_riff = new getid3_riff($getid3_temp); 0083 $getid3_riff->Analyze(); 0084 $info['avdataoffset'] = $getid3_temp->info['avdataoffset']; 0085 $info['riff'] = $getid3_temp->info['riff']; 0086 $info['error'] = $getid3_temp->info['error']; 0087 $info['warning'] = $getid3_temp->info['warning']; 0088 $info['lpac']['comments']['comment'] = $getid3_temp->info['comments']; 0089 $info['audio']['sample_rate'] = $getid3_temp->info['audio']['sample_rate']; 0090 unset($getid3_temp, $getid3_riff); 0091 0092 $info['audio']['channels'] = ($info['lpac']['flags']['stereo'] ? 2 : 1); 0093 0094 if ($info['lpac']['flags']['24_bit']) { 0095 $info['audio']['bits_per_sample'] = $info['riff']['audio'][0]['bits_per_sample']; 0096 } elseif ($info['lpac']['flags']['16_bit']) { 0097 $info['audio']['bits_per_sample'] = 16; 0098 } else { 0099 $info['audio']['bits_per_sample'] = 8; 0100 } 0101 0102 if ($info['lpac']['flags']['fast_compress']) { 0103 // fast 0104 $info['audio']['encoder_options'] = '-1'; 0105 } else { 0106 switch ($info['lpac']['max_prediction_order']) { 0107 case 20: // simple 0108 $info['audio']['encoder_options'] = '-2'; 0109 break; 0110 case 30: // medium 0111 $info['audio']['encoder_options'] = '-3'; 0112 break; 0113 case 40: // high 0114 $info['audio']['encoder_options'] = '-4'; 0115 break; 0116 case 60: // extrahigh 0117 $info['audio']['encoder_options'] = '-5'; 0118 break; 0119 } 0120 } 0121 0122 $info['playtime_seconds'] = $info['lpac']['total_samples'] / $info['audio']['sample_rate']; 0123 $info['audio']['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds']; 0124 0125 return true; 0126 } 0127 0128 }