3 /////////////////////////////////////////////////////////////////
4 /// getID3() by James Heinrich <info@getid3.org> //
5 // available at https://github.com/JamesHeinrich/getID3 //
6 // or https://www.getid3.org //
7 // or http://getid3.sourceforge.net //
8 // see readme.txt for more details //
9 /////////////////////////////////////////////////////////////////
11 // module.audio.lpac.php //
12 // module for analyzing LPAC Audio files //
13 // dependencies: module.audio-video.riff.php //
15 /////////////////////////////////////////////////////////////////
17 if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
20 getid3_lib
::IncludeDependency(GETID3_INCLUDEPATH
.'module.audio-video.riff.php', __FILE__
, true);
22 class getid3_lpac
extends getid3_handler
27 public function Analyze() {
28 $info = &$this->getid3
->info
;
30 $this->fseek($info['avdataoffset']);
31 $LPACheader = $this->fread(14);
32 $StreamMarker = substr($LPACheader, 0, 4);
33 if ($StreamMarker != 'LPAC') {
34 $this->error('Expected "LPAC" at offset '.$info['avdataoffset'].', found "'.$StreamMarker.'"');
37 $info['avdataoffset'] +
= 14;
39 $info['fileformat'] = 'lpac';
40 $info['audio']['dataformat'] = 'lpac';
41 $info['audio']['lossless'] = true;
42 $info['audio']['bitrate_mode'] = 'vbr';
44 $info['lpac']['file_version'] = getid3_lib
::BigEndian2Int(substr($LPACheader, 4, 1));
45 $flags['audio_type'] = getid3_lib
::BigEndian2Int(substr($LPACheader, 5, 1));
46 $info['lpac']['total_samples']= getid3_lib
::BigEndian2Int(substr($LPACheader, 6, 4));
47 $flags['parameters'] = getid3_lib
::BigEndian2Int(substr($LPACheader, 10, 4));
49 $info['lpac']['flags']['is_wave'] = (bool) ($flags['audio_type'] & 0x40);
50 $info['lpac']['flags']['stereo'] = (bool) ($flags['audio_type'] & 0x04);
51 $info['lpac']['flags']['24_bit'] = (bool) ($flags['audio_type'] & 0x02);
52 $info['lpac']['flags']['16_bit'] = (bool) ($flags['audio_type'] & 0x01);
54 if ($info['lpac']['flags']['24_bit'] && $info['lpac']['flags']['16_bit']) {
55 $this->warning('24-bit and 16-bit flags cannot both be set');
58 $info['lpac']['flags']['fast_compress'] = (bool) ($flags['parameters'] & 0x40000000);
59 $info['lpac']['flags']['random_access'] = (bool) ($flags['parameters'] & 0x08000000);
60 $info['lpac']['block_length'] = pow(2, (($flags['parameters'] & 0x07000000) >> 24)) * 256;
61 $info['lpac']['flags']['adaptive_prediction_order'] = (bool) ($flags['parameters'] & 0x00800000);
62 $info['lpac']['flags']['adaptive_quantization'] = (bool) ($flags['parameters'] & 0x00400000);
63 $info['lpac']['flags']['joint_stereo'] = (bool) ($flags['parameters'] & 0x00040000);
64 $info['lpac']['quantization'] = ($flags['parameters'] & 0x00001F00) >> 8;
65 $info['lpac']['max_prediction_order'] = ($flags['parameters'] & 0x0000003F);
67 if ($info['lpac']['flags']['fast_compress'] && ($info['lpac']['max_prediction_order'] != 3)) {
68 $this->warning('max_prediction_order expected to be "3" if fast_compress is true, actual value is "'.$info['lpac']['max_prediction_order'].'"');
70 switch ($info['lpac']['file_version']) {
72 if ($info['lpac']['flags']['adaptive_quantization']) {
73 $this->warning('adaptive_quantization expected to be false in LPAC file stucture v6, actually true');
75 if ($info['lpac']['quantization'] != 20) {
76 $this->warning('Quantization expected to be 20 in LPAC file stucture v6, actually '.$info['lpac']['flags']['Q']);
81 //$this->warning('This version of getID3() ['.$this->getid3->version().'] only supports LPAC file format version 6, this file is version '.$info['lpac']['file_version'].' - please report to info@getid3.org');
85 $getid3_temp = new getID3();
86 $getid3_temp->openfile($this->getid3
->filename
, $this->getid3
->info
['filesize'], $this->getid3
->fp
);
87 $getid3_temp->info
= $info;
88 $getid3_riff = new getid3_riff($getid3_temp);
89 $getid3_riff->Analyze();
90 $info['avdataoffset'] = $getid3_temp->info
['avdataoffset'];
91 $info['riff'] = $getid3_temp->info
['riff'];
92 $info['error'] = $getid3_temp->info
['error'];
93 $info['warning'] = $getid3_temp->info
['warning'];
94 $info['lpac']['comments']['comment'] = $getid3_temp->info
['comments'];
95 $info['audio']['sample_rate'] = $getid3_temp->info
['audio']['sample_rate'];
96 unset($getid3_temp, $getid3_riff);
98 $info['audio']['channels'] = ($info['lpac']['flags']['stereo'] ?
2 : 1);
100 if ($info['lpac']['flags']['24_bit']) {
101 $info['audio']['bits_per_sample'] = $info['riff']['audio'][0]['bits_per_sample'];
102 } elseif ($info['lpac']['flags']['16_bit']) {
103 $info['audio']['bits_per_sample'] = 16;
105 $info['audio']['bits_per_sample'] = 8;
108 if ($info['lpac']['flags']['fast_compress']) {
110 $info['audio']['encoder_options'] = '-1';
112 switch ($info['lpac']['max_prediction_order']) {
114 $info['audio']['encoder_options'] = '-2';
117 $info['audio']['encoder_options'] = '-3';
120 $info['audio']['encoder_options'] = '-4';
122 case 60: // extrahigh
123 $info['audio']['encoder_options'] = '-5';
128 $info['playtime_seconds'] = $info['lpac']['total_samples'] / $info['audio']['sample_rate'];
129 $info['audio']['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds'];