Mercurial > judyates
view e2gallerypro/e2upload/Backend/Assets/getid3/module.audio.lpac.php @ 13:f16185fe9ed9 judyates
[svn r14]
| author | rlm |
|---|---|
| date | Mon, 12 Apr 2010 03:30:00 -0400 |
| parents | 3f6b44aa6b35 |
| children |
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1 <?php2 // +----------------------------------------------------------------------+3 // | PHP version 5 |4 // +----------------------------------------------------------------------+5 // | Copyright (c) 2002-2006 James Heinrich, Allan Hansen |6 // +----------------------------------------------------------------------+7 // | This source file is subject to version 2 of the GPL license, |8 // | that is bundled with this package in the file license.txt and is |9 // | available through the world-wide-web at the following url: |10 // | http://www.gnu.org/copyleft/gpl.html |11 // +----------------------------------------------------------------------+12 // | getID3() - http://getid3.sourceforge.net or http://www.getid3.org |13 // +----------------------------------------------------------------------+14 // | Authors: James Heinrich <infoØgetid3*org> |15 // | Allan Hansen <ahØartemis*dk> |16 // +----------------------------------------------------------------------+17 // | module.audio.lpac.php |18 // | Module for analyzing LPAC Audio files |19 // | dependencies: module.audio-video.riff.php |20 // +----------------------------------------------------------------------+21 //22 // $Id: module.audio.lpac.php,v 1.2 2006/11/02 10:48:01 ah Exp $26 class getid3_lpac extends getid3_handler27 {29 public function Analyze() {31 $getid3 = $this->getid3;33 $getid3->include_module('audio-video.riff');35 // Magic bytes - 'LPAC'37 fseek($getid3->fp, $getid3->info['avdataoffset'], SEEK_SET);38 $lpac_header = fread($getid3->fp, 14);40 $getid3->info['avdataoffset'] += 14;42 $getid3->info['lpac'] = array ();43 $info_lpac = &$getid3->info['lpac'];45 $getid3->info['fileformat'] = 'lpac';46 $getid3->info['audio']['dataformat'] = 'lpac';47 $getid3->info['audio']['lossless'] = true;48 $getid3->info['audio']['bitrate_mode'] = 'vbr';50 $info_lpac['file_version'] = getid3_lib::BigEndian2Int($lpac_header{4});51 $flags['audio_type'] = getid3_lib::BigEndian2Int($lpac_header{5});52 $info_lpac['total_samples'] = getid3_lib::BigEndian2Int(substr($lpac_header, 6, 4));53 $flags['parameters'] = getid3_lib::BigEndian2Int(substr($lpac_header, 10, 4));55 $info_lpac['flags']['is_wave'] = (bool)($flags['audio_type'] & 0x40);56 $info_lpac['flags']['stereo'] = (bool)($flags['audio_type'] & 0x04);57 $info_lpac['flags']['24_bit'] = (bool)($flags['audio_type'] & 0x02);58 $info_lpac['flags']['16_bit'] = (bool)($flags['audio_type'] & 0x01);60 if ($info_lpac['flags']['24_bit'] && $info_lpac['flags']['16_bit']) {61 $getid3->warning('24-bit and 16-bit flags cannot both be set');62 }64 $info_lpac['flags']['fast_compress'] = (bool)($flags['parameters'] & 0x40000000);65 $info_lpac['flags']['random_access'] = (bool)($flags['parameters'] & 0x08000000);66 $info_lpac['block_length'] = pow(2, (($flags['parameters'] & 0x07000000) >> 24)) * 256;67 $info_lpac['flags']['adaptive_prediction_order'] = (bool)($flags['parameters'] & 0x00800000);68 $info_lpac['flags']['adaptive_quantization'] = (bool)($flags['parameters'] & 0x00400000);69 $info_lpac['flags']['joint_stereo'] = (bool)($flags['parameters'] & 0x00040000);70 $info_lpac['quantization'] = ($flags['parameters'] & 0x00001F00) >> 8;71 $info_lpac['max_prediction_order'] = ($flags['parameters'] & 0x0000003F);73 if ($info_lpac['flags']['fast_compress'] && ($info_lpac['max_prediction_order'] != 3)) {74 $getid3->warning('max_prediction_order expected to be "3" if fast_compress is true, actual value is "'.$info_lpac['max_prediction_order'].'"');75 }77 switch ($info_lpac['file_version']) {79 case 6:80 if ($info_lpac['flags']['adaptive_quantization']) {81 $getid3->warning('adaptive_quantization expected to be false in LPAC file stucture v6, actually true');82 }83 if ($info_lpac['quantization'] != 20) {84 $getid3->warning('Quantization expected to be 20 in LPAC file stucture v6, actually '.$info_lpac['flags']['Q']);85 }86 break;89 default:90 //$getid3->warning('This version of getID3() only supports LPAC file format version 6, this file is version '.$info_lpac['file_version'].' - please report to info@getid3.org');91 break;92 }94 // Clone getid3 - messing with something - better safe than sorry95 $clone = clone $getid3;97 // Analyze clone by fp98 $riff = new getid3_riff($clone);99 $riff->Analyze();101 // Import from clone and destroy102 $getid3->info['avdataoffset'] = $clone->info['avdataoffset'];103 $getid3->info['riff'] = $clone->info['riff'];104 //$info_lpac['comments']['comment'] = $clone->info['comments'];105 $getid3->info['audio']['sample_rate'] = $clone->info['audio']['sample_rate'];106 $getid3->warnings($clone->warnings());107 unset($clone);109 $getid3->info['audio']['channels'] = ($info_lpac['flags']['stereo'] ? 2 : 1);111 if ($info_lpac['flags']['24_bit']) {112 $getid3->info['audio']['bits_per_sample'] = $getid3->info['riff']['audio'][0]['bits_per_sample'];113 } elseif ($info_lpac['flags']['16_bit']) {114 $getid3->info['audio']['bits_per_sample'] = 16;115 } else {116 $getid3->info['audio']['bits_per_sample'] = 8;117 }119 if ($info_lpac['flags']['fast_compress']) {120 // fast121 $getid3->info['audio']['encoder_options'] = '-1';122 } else {123 switch ($info_lpac['max_prediction_order']) {124 case 20: // simple125 $getid3->info['audio']['encoder_options'] = '-2';126 break;127 case 30: // medium128 $getid3->info['audio']['encoder_options'] = '-3';129 break;130 case 40: // high131 $getid3->info['audio']['encoder_options'] = '-4';132 break;133 case 60: // extrahigh134 $getid3->info['audio']['encoder_options'] = '-5';135 break;136 }137 }139 $getid3->info['playtime_seconds'] = $info_lpac['total_samples'] / $getid3->info['audio']['sample_rate'];140 $getid3->info['audio']['bitrate'] = (($getid3->info['avdataend'] - $getid3->info['avdataoffset']) * 8) / $getid3->info['playtime_seconds'];142 return true;143 }145 }148 ?>