rlm@3: <?php
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | PHP version 5                                                        |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | Copyright (c) 2002-2006 James Heinrich, Allan Hansen                 |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | This source file is subject to version 2 of the GPL license,         |
rlm@3: // | that is bundled with this package in the file license.txt and is     |
rlm@3: // | available through the world-wide-web at the following url:           |
rlm@3: // | http://www.gnu.org/copyleft/gpl.html                                 |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | getID3() - http://getid3.sourceforge.net or http://www.getid3.org    |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | Authors: James Heinrich <infoØgetid3*org>                            |
rlm@3: // |          Allan Hansen <ahØartemis*dk>                                |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: // | module.audio.mpc.php                                                 |
rlm@3: // | Module for analyzing Musepack/MPEG+ Audio files                      |
rlm@3: // | dependencies: NONE                                                   |
rlm@3: // +----------------------------------------------------------------------+
rlm@3: //
rlm@3: // $Id: module.audio.mpc.php,v 1.3 2006/11/02 10:48:01 ah Exp $
rlm@3: 
rlm@3:         
rlm@3:         
rlm@3: class getid3_mpc extends getid3_handler
rlm@3: {
rlm@3: 
rlm@3:     public function Analyze() {
rlm@3: 
rlm@3:         $getid3 = $this->getid3;
rlm@3:         
rlm@3:         // http://www.uni-jena.de/~pfk/mpp/sv8/header.html
rlm@3: 
rlm@3:         $getid3->info['fileformat']            = 'mpc';
rlm@3:         $getid3->info['audio']['dataformat']   = 'mpc';
rlm@3:         $getid3->info['audio']['bitrate_mode'] = 'vbr';
rlm@3:         $getid3->info['audio']['channels']     = 2;  // the format appears to be hardcoded for stereo only
rlm@3:         $getid3->info['audio']['lossless']     = false;
rlm@3:         
rlm@3:         $getid3->info['mpc']['header'] = array ();
rlm@3:         $info_mpc_header = &$getid3->info['mpc']['header'];
rlm@3:         $info_mpc_header['size'] = 28;
rlm@3:         $info_mpc_header['raw']['preamble'] = 'MP+';    // Magic bytes
rlm@3:         
rlm@3:         fseek($getid3->fp, $getid3->info['avdataoffset'], SEEK_SET);
rlm@3:         $mpc_header_data = fread($getid3->fp, 28);
rlm@3:         
rlm@3:         $stream_version_byte = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 3, 1));
rlm@3:         $info_mpc_header['stream_major_version'] = ($stream_version_byte & 0x0F);
rlm@3:         $info_mpc_header['stream_minor_version'] = ($stream_version_byte & 0xF0) >> 4;
rlm@3:         if ($info_mpc_header['stream_major_version'] != 7) {
rlm@3:             throw new getid3_exception('Only Musepack SV7 supported');
rlm@3:         }
rlm@3:             
rlm@3:         $info_mpc_header['frame_count'] = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 4, 4));
rlm@3:         
rlm@3:         $info_mpc_header['raw']['title_peak']      = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 12, 2));
rlm@3:         $info_mpc_header['raw']['title_gain']      = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 14, 2), true);
rlm@3:         $info_mpc_header['raw']['album_peak']      = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 16, 2));
rlm@3:         $info_mpc_header['raw']['album_gain']      = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 18, 2), true);
rlm@3:         
rlm@3:         $info_mpc_header['raw']['not_sure_what']   = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 24, 3));
rlm@3:         $info_mpc_header['raw']['encoder_version'] = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 27, 1));
rlm@3:         
rlm@3:         $flags_dword1                              = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 8, 4));
rlm@3:         $flags_dword2                              = getid3_lib::LittleEndian2Int(substr($mpc_header_data, 20, 4));
rlm@3:         
rlm@3:         $info_mpc_header['intensity_stereo']   = (bool)(($flags_dword1 & 0x80000000) >> 31);
rlm@3:         $info_mpc_header['mid_side_stereo']    = (bool)(($flags_dword1 & 0x40000000) >> 30);
rlm@3:         $info_mpc_header['max_subband']        =         ($flags_dword1 & 0x3F000000) >> 24;
rlm@3:         $info_mpc_header['raw']['profile']     =         ($flags_dword1 & 0x00F00000) >> 20;
rlm@3:         $info_mpc_header['begin_loud']         = (bool)(($flags_dword1 & 0x00080000) >> 19);
rlm@3:         $info_mpc_header['end_loud']           = (bool)(($flags_dword1 & 0x00040000) >> 18);
rlm@3:         $info_mpc_header['raw']['sample_rate'] =         ($flags_dword1 & 0x00030000) >> 16;
rlm@3:         $info_mpc_header['max_level']          =         ($flags_dword1 & 0x0000FFFF);
rlm@3:         
rlm@3:         $info_mpc_header['true_gapless']       = (bool)(($flags_dword2 & 0x80000000) >> 31);
rlm@3:         $info_mpc_header['last_frame_length']  =         ($flags_dword2 & 0x7FF00000) >> 20;
rlm@3:         
rlm@3:         $info_mpc_header['profile']            = getid3_mpc::MPCprofileNameLookup($info_mpc_header['raw']['profile']);
rlm@3:         $info_mpc_header['sample_rate']        = getid3_mpc::MPCfrequencyLookup($info_mpc_header['raw']['sample_rate']);
rlm@3:         $getid3->info['audio']['sample_rate']  = $info_mpc_header['sample_rate'];
rlm@3:         $info_mpc_header['samples']            = ((($info_mpc_header['frame_count'] - 1) * 1152) + $info_mpc_header['last_frame_length']) * $getid3->info['audio']['channels'];
rlm@3: 
rlm@3:         $getid3->info['playtime_seconds'] = ($info_mpc_header['samples'] / $getid3->info['audio']['channels']) / $getid3->info['audio']['sample_rate'];
rlm@3: 
rlm@3:         $getid3->info['avdataoffset'] += $info_mpc_header['size'];
rlm@3:         
rlm@3:         $getid3->info['audio']['bitrate'] = (($getid3->info['avdataend'] - $getid3->info['avdataoffset']) * 8) / $getid3->info['playtime_seconds'];
rlm@3: 
rlm@3:         $info_mpc_header['title_peak']    = $info_mpc_header['raw']['title_peak'];
rlm@3:         $info_mpc_header['title_peak_db'] = getid3_mpc::MPCpeakDBLookup($info_mpc_header['title_peak']);
rlm@3:         if ($info_mpc_header['raw']['title_gain'] < 0) {
rlm@3:             $info_mpc_header['title_gain_db'] = (float)(32768 + $info_mpc_header['raw']['title_gain']) / -100;
rlm@3:         } 
rlm@3:         else {
rlm@3:             $info_mpc_header['title_gain_db'] = (float)$info_mpc_header['raw']['title_gain'] / 100;
rlm@3:         }
rlm@3: 
rlm@3:         $info_mpc_header['album_peak']    = $info_mpc_header['raw']['album_peak'];
rlm@3:         $info_mpc_header['album_peak_db'] = getid3_mpc::MPCpeakDBLookup($info_mpc_header['album_peak']);
rlm@3:         if ($info_mpc_header['raw']['album_gain'] < 0) {
rlm@3:             $info_mpc_header['album_gain_db'] = (float)(32768 + $info_mpc_header['raw']['album_gain']) / -100;
rlm@3:         } 
rlm@3:         else {
rlm@3:             $info_mpc_header['album_gain_db'] = (float)$info_mpc_header['raw']['album_gain'] / 100;;
rlm@3:         }
rlm@3:         $info_mpc_header['encoder_version'] = getid3_mpc::MPCencoderVersionLookup($info_mpc_header['raw']['encoder_version']);
rlm@3: 
rlm@3:         $getid3->info['replay_gain']['track']['adjustment'] = $info_mpc_header['title_gain_db'];
rlm@3:         $getid3->info['replay_gain']['album']['adjustment'] = $info_mpc_header['album_gain_db'];
rlm@3: 
rlm@3:         if ($info_mpc_header['title_peak'] > 0) {
rlm@3:             $getid3->info['replay_gain']['track']['peak'] = $info_mpc_header['title_peak'];
rlm@3:         } 
rlm@3:         elseif (round($info_mpc_header['max_level'] * 1.18) > 0) {
rlm@3:             $getid3->info['replay_gain']['track']['peak'] = (int)(round($info_mpc_header['max_level'] * 1.18)); // why? I don't know - see mppdec.c
rlm@3:         }
rlm@3:         if ($info_mpc_header['album_peak'] > 0) {
rlm@3:             $getid3->info['replay_gain']['album']['peak'] = $info_mpc_header['album_peak'];
rlm@3:         }
rlm@3: 
rlm@3:         $getid3->info['audio']['encoder']         = $info_mpc_header['encoder_version'];
rlm@3:         $getid3->info['audio']['encoder_options'] = $info_mpc_header['profile'];
rlm@3:         
rlm@3:         return true;
rlm@3:     }
rlm@3: 
rlm@3: 
rlm@3: 
rlm@3:     public static function MPCprofileNameLookup($profileid) {
rlm@3:         
rlm@3:         static $lookup = array (
rlm@3:             0  => 'no profile',
rlm@3:             1  => 'Experimental',
rlm@3:             2  => 'unused',
rlm@3:             3  => 'unused',
rlm@3:             4  => 'unused',
rlm@3:             5  => 'below Telephone (q = 0.0)',
rlm@3:             6  => 'below Telephone (q = 1.0)',
rlm@3:             7  => 'Telephone (q = 2.0)',
rlm@3:             8  => 'Thumb (q = 3.0)',
rlm@3:             9  => 'Radio (q = 4.0)',
rlm@3:             10 => 'Standard (q = 5.0)',
rlm@3:             11 => 'Extreme (q = 6.0)',
rlm@3:             12 => 'Insane (q = 7.0)',
rlm@3:             13 => 'BrainDead (q = 8.0)',
rlm@3:             14 => 'above BrainDead (q = 9.0)',
rlm@3:             15 => 'above BrainDead (q = 10.0)'
rlm@3:         );
rlm@3:         return (isset($lookup[$profileid]) ? $lookup[$profileid] : 'invalid');
rlm@3:     }
rlm@3: 
rlm@3: 
rlm@3: 
rlm@3:     public static function MPCfrequencyLookup($frequencyid) {
rlm@3:         
rlm@3:         static $lookup = array (
rlm@3:             0 => 44100,
rlm@3:             1 => 48000,
rlm@3:             2 => 37800,
rlm@3:             3 => 32000
rlm@3:         );
rlm@3:         return (isset($lookup[$frequencyid]) ? $lookup[$frequencyid] : 'invalid');
rlm@3:     }
rlm@3: 
rlm@3: 
rlm@3: 
rlm@3:     public static function MPCpeakDBLookup($int_value) {
rlm@3:         
rlm@3:         if ($int_value > 0) {
rlm@3:             return ((log10($int_value) / log10(2)) - 15) * 6;
rlm@3:         }
rlm@3:         return false;
rlm@3:     }
rlm@3: 
rlm@3: 
rlm@3: 
rlm@3:     public static function MPCencoderVersionLookup($encoder_version) {
rlm@3:     
rlm@3:         //Encoder version * 100  (106 = 1.06)
rlm@3:         //EncoderVersion % 10 == 0        Release (1.0)
rlm@3:         //EncoderVersion %  2 == 0        Beta (1.06)
rlm@3:         //EncoderVersion %  2 == 1        Alpha (1.05a...z)
rlm@3: 
rlm@3:         if ($encoder_version == 0) {
rlm@3:             // very old version, not known exactly which
rlm@3:             return 'Buschmann v1.7.0-v1.7.9 or Klemm v0.90-v1.05';
rlm@3:         }
rlm@3: 
rlm@3:         if (($encoder_version % 10) == 0) {
rlm@3: 
rlm@3:             // release version
rlm@3:             return number_format($encoder_version / 100, 2);
rlm@3: 
rlm@3:         } elseif (($encoder_version % 2) == 0) {
rlm@3: 
rlm@3:             // beta version
rlm@3:             return number_format($encoder_version / 100, 2).' beta';
rlm@3: 
rlm@3:         }
rlm@3: 
rlm@3:         // alpha version
rlm@3:         return number_format($encoder_version / 100, 2).' alpha';
rlm@3:     }
rlm@3: 
rlm@3: }
rlm@3: 
rlm@3: 
rlm@3: ?>