Mercurial > judyates

     1 <?php

     2 // +----------------------------------------------------------------------+

     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.la.php                                                  |

    18 // | Module for analyzing LA udio files                                   |

    19 // | dependencies: module.audio-video.riff.php                            |

    20 // +----------------------------------------------------------------------+

    21 //

    22 // $Id: module.audio.la.php,v 1.2 2006/11/02 10:48:01 ah Exp $

    23 

    24         

    25         

    26 class getid3_la extends getid3_handler

    27 {

    28 

    29     public function Analyze() {

    30         

    31         $getid3 = $this->getid3;

    32         

    33         $getid3->include_module('audio-video.riff');

    34         

    35         fseek($getid3->fp, $getid3->info['avdataoffset'], SEEK_SET);

    36         $raw_data = fread($getid3->fp, getid3::FREAD_BUFFER_SIZE);

    37     

    38         $getid3->info['fileformat']          = 'la';

    39         $getid3->info['audio']['dataformat'] = 'la';

    40         $getid3->info['audio']['lossless']   = true;

    41 

    42         $getid3->info['la']['version_major'] = (int)$raw_data{2};

    43         $getid3->info['la']['version_minor'] = (int)$raw_data{3};

    44         $getid3->info['la']['version']       = (float)$getid3->info['la']['version_major'] + ($getid3->info['la']['version_minor'] / 10);

    45 

    46         $getid3->info['la']['uncompressed_size'] = getid3_lib::LittleEndian2Int(substr($raw_data, 4, 4));

    47         

    48         $wave_chunk = substr($raw_data, 8, 4);

    49         if ($wave_chunk !== 'WAVE') {

    50             throw new getid3_exception('Expected "WAVE" ('.getid3_lib::PrintHexBytes('WAVE').') at offset 8, found "'.$wave_chunk.'" ('.getid3_lib::PrintHexBytes($wave_chunk).') instead.');

    51         }

    52         

    53         $offset = 12;

    54 

    55         $getid3->info['la']['fmt_size'] = 24;

    56         if ($getid3->info['la']['version'] >= 0.3) {

    57 

    58             $getid3->info['la']['fmt_size']    = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 4));

    59             $getid3->info['la']['header_size'] = 49 + $getid3->info['la']['fmt_size'] - 24;

    60             $offset += 4;

    61 

    62         } else {

    63 

    64             // version 0.2 didn't support additional data blocks

    65             $getid3->info['la']['header_size'] = 41;

    66         }

    67 

    68         $fmt_chunk = substr($raw_data, $offset, 4);

    69         if ($fmt_chunk !== 'fmt ') {

    70             throw new getid3_exception('Expected "fmt " ('.getid3_lib::PrintHexBytes('fmt ').') at offset '.$offset.', found "'.$fmt_chunk.'" ('.getid3_lib::PrintHexBytes($fmt_chunk).') instead.');

    71         }

    72         $offset += 4;

    73         

    74         $fmt_size = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 4));

    75         $offset += 4;

    76 

    77         $getid3->info['la']['raw']['format'] = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 2));

    78         $offset += 2;

    79         

    80         getid3_lib::ReadSequence('LittleEndian2Int', $getid3->info['la'], $raw_data, $offset,

    81             array (

    82                 'channels'         => 2,

    83                 'sample_rate'      => 4,

    84                 'bytes_per_second' => 4,

    85                 'bytes_per_sample' => 2,

    86                 'bits_per_sample'  => 2,

    87                 'samples'          => 4

    88             )

    89         );

    90         $offset += 18;

    91         

    92         $getid3->info['la']['raw']['flags'] = getid3_lib::LittleEndian2Int($raw_data{$offset++});

    93         

    94         $getid3->info['la']['flags']['seekable']             = (bool)($getid3->info['la']['raw']['flags'] & 0x01);

    95         if ($getid3->info['la']['version'] >= 0.4) {

    96             $getid3->info['la']['flags']['high_compression'] = (bool)($getid3->info['la']['raw']['flags'] & 0x02);

    97         }

    98 

    99         $getid3->info['la']['original_crc'] = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 4));

   100         $offset += 4;

   101 

   102         // mikeØbevin*de

   103         // Basically, the blocksize/seekevery are 61440/19 in La0.4 and 73728/16

   104         // in earlier versions. A seekpoint is added every blocksize * seekevery

   105         // samples, so 4 * int(totalSamples / (blockSize * seekEvery)) should

   106         // give the number of bytes used for the seekpoints. Of course, if seeking

   107         // is disabled, there are no seekpoints stored.

   108         

   109         if ($getid3->info['la']['version'] >= 0.4) {

   110             $getid3->info['la']['blocksize'] = 61440;

   111             $getid3->info['la']['seekevery'] = 19;

   112         } else {

   113             $getid3->info['la']['blocksize'] = 73728;

   114             $getid3->info['la']['seekevery'] = 16;

   115         }

   116 

   117         $getid3->info['la']['seekpoint_count'] = 0;

   118         if ($getid3->info['la']['flags']['seekable']) {

   119             $getid3->info['la']['seekpoint_count'] = floor($getid3->info['la']['samples'] / ($getid3->info['la']['blocksize'] * $getid3->info['la']['seekevery']));

   120 

   121             for ($i = 0; $i < $getid3->info['la']['seekpoint_count']; $i++) {

   122                 $getid3->info['la']['seekpoints'][] = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 4));

   123                 $offset += 4;

   124             }

   125         }

   126 

   127         if ($getid3->info['la']['version'] >= 0.3) {

   128 

   129             // Following the main header information, the program outputs all of the

   130             // seekpoints. Following these is what I called the 'footer start',

   131             // i.e. the position immediately after the La audio data is finished.

   132         

   133             $getid3->info['la']['footerstart'] = getid3_lib::LittleEndian2Int(substr($raw_data, $offset, 4));

   134             $offset += 4;

   135 

   136             if ($getid3->info['la']['footerstart'] > $getid3->info['filesize']) {

   137                 $getid3->warning('FooterStart value points to offset '.$getid3->info['la']['footerstart'].' which is beyond end-of-file ('.$getid3->info['filesize'].')');

   138                 $getid3->info['la']['footerstart'] = $getid3->info['filesize'];

   139             }

   140 

   141         } else {

   142 

   143             // La v0.2 didn't have FooterStart value

   144             $getid3->info['la']['footerstart'] = $getid3->info['avdataend'];

   145 

   146         }

   147 

   148         if ($getid3->info['la']['footerstart'] < $getid3->info['avdataend']) {

   149         

   150             // Create riff header

   151             $riff_data = 'WAVE';

   152             if ($getid3->info['la']['version'] == 0.2) {

   153                 $riff_data .= substr($raw_data, 12, 24);

   154             } else {

   155                 $riff_data .= substr($raw_data, 16, 24);

   156             }

   157             if ($getid3->info['la']['footerstart'] < $getid3->info['avdataend']) {

   158                 fseek($getid3->fp, $getid3->info['la']['footerstart'], SEEK_SET);

   159                 $riff_data .= fread($getid3->fp, $getid3->info['avdataend'] - $getid3->info['la']['footerstart']);

   160             }

   161             $riff_data = 'RIFF'.getid3_lib::LittleEndian2String(strlen($riff_data), 4, false).$riff_data;

   162             

   163             // Clone getid3 - messing with offsets - better safe than sorry

   164             $clone = clone $getid3;

   165             

   166             // Analyze clone by string

   167             $riff = new getid3_riff($clone);

   168             $riff->AnalyzeString($riff_data);

   169             

   170             // Import from clone and destroy

   171             $getid3->info['riff']   = $clone->info['riff'];

   172             $getid3->warnings($clone->warnings());

   173             unset($clone);

   174         }

   175 

   176         // $getid3->info['avdataoffset'] should be zero to begin with, but just in case it's not, include the addition anyway

   177         $getid3->info['avdataend']    = $getid3->info['avdataoffset'] + $getid3->info['la']['footerstart'];

   178         $getid3->info['avdataoffset'] = $getid3->info['avdataoffset'] + $offset;

   179 

   180         $getid3->info['la']['compression_ratio']  = (float)(($getid3->info['avdataend'] - $getid3->info['avdataoffset']) / $getid3->info['la']['uncompressed_size']);

   181         $getid3->info['playtime_seconds']         = (float)($getid3->info['la']['samples'] / $getid3->info['la']['sample_rate']) / $getid3->info['la']['channels'];

   182 

   183         $getid3->info['audio']['bitrate']         = ($getid3->info['avdataend'] - $getid3->info['avdataoffset']) * 8 / $getid3->info['playtime_seconds'];

   184         $getid3->info['audio']['bits_per_sample'] = $getid3->info['la']['bits_per_sample'];

   185 

   186         $getid3->info['audio']['channels']        = $getid3->info['la']['channels'];

   187         $getid3->info['audio']['sample_rate']     = (int)$getid3->info['la']['sample_rate'];

   188         $getid3->info['audio']['encoder']         = 'LA v'.$getid3->info['la']['version'];

   189 

   190         return true;

   191     }

   192 

   193 }

   194 

   195 

   196 ?>