ILIAS  release_5-4 Revision v5.4.26-12-gabc799a52e6
module.audio.la.php
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1 <?php
4 // available at http://getid3.sourceforge.net //
5 // or http://www.getid3.org //
6 // also https://github.com/JamesHeinrich/getID3 //
8 // See readme.txt for more details //
10 // //
11 // module.audio.la.php //
12 // module for analyzing LA (LosslessAudio) audio files //
13 // dependencies: module.audio.riff.php //
14 // ///
16 
17 getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);
18 
19 class getid3_la extends getid3_handler
20 {
21 
22  public function Analyze() {
23  $info = &$this->getid3->info;
24 
25  $offset = 0;
26  $this->fseek($info['avdataoffset']);
27  $rawdata = $this->fread($this->getid3->fread_buffer_size());
28 
29  switch (substr($rawdata, $offset, 4)) {
30  case 'LA02':
31  case 'LA03':
32  case 'LA04':
33  $info['fileformat'] = 'la';
34  $info['audio']['dataformat'] = 'la';
35  $info['audio']['lossless'] = true;
36 
37  $info['la']['version_major'] = (int) substr($rawdata, $offset + 2, 1);
38  $info['la']['version_minor'] = (int) substr($rawdata, $offset + 3, 1);
39  $info['la']['version'] = (float) $info['la']['version_major'] + ($info['la']['version_minor'] / 10);
40  $offset += 4;
41 
42  $info['la']['uncompressed_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
43  $offset += 4;
44  if ($info['la']['uncompressed_size'] == 0) {
45  $this->error('Corrupt LA file: uncompressed_size == zero');
46  return false;
47  }
48 
49  $WAVEchunk = substr($rawdata, $offset, 4);
50  if ($WAVEchunk !== 'WAVE') {
51  $this->error('Expected "WAVE" ('.getid3_lib::PrintHexBytes('WAVE').') at offset '.$offset.', found "'.$WAVEchunk.'" ('.getid3_lib::PrintHexBytes($WAVEchunk).') instead.');
52  return false;
53  }
54  $offset += 4;
55 
56  $info['la']['fmt_size'] = 24;
57  if ($info['la']['version'] >= 0.3) {
58 
59  $info['la']['fmt_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
60  $info['la']['header_size'] = 49 + $info['la']['fmt_size'] - 24;
61  $offset += 4;
62 
63  } else {
64 
65  // version 0.2 didn't support additional data blocks
66  $info['la']['header_size'] = 41;
67 
68  }
69 
70  $fmt_chunk = substr($rawdata, $offset, 4);
71  if ($fmt_chunk !== 'fmt ') {
72  $this->error('Expected "fmt " ('.getid3_lib::PrintHexBytes('fmt ').') at offset '.$offset.', found "'.$fmt_chunk.'" ('.getid3_lib::PrintHexBytes($fmt_chunk).') instead.');
73  return false;
74  }
75  $offset += 4;
76  $fmt_size = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
77  $offset += 4;
78 
79  $info['la']['raw']['format'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
80  $offset += 2;
81 
82  $info['la']['channels'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
83  $offset += 2;
84  if ($info['la']['channels'] == 0) {
85  $this->error('Corrupt LA file: channels == zero');
86  return false;
87  }
88 
89  $info['la']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
90  $offset += 4;
91  if ($info['la']['sample_rate'] == 0) {
92  $this->error('Corrupt LA file: sample_rate == zero');
93  return false;
94  }
95 
96  $info['la']['bytes_per_second'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
97  $offset += 4;
98  $info['la']['bytes_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
99  $offset += 2;
100  $info['la']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
101  $offset += 2;
102 
103  $info['la']['samples'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
104  $offset += 4;
105 
106  $info['la']['raw']['flags'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 1));
107  $offset += 1;
108  $info['la']['flags']['seekable'] = (bool) ($info['la']['raw']['flags'] & 0x01);
109  if ($info['la']['version'] >= 0.4) {
110  $info['la']['flags']['high_compression'] = (bool) ($info['la']['raw']['flags'] & 0x02);
111  }
112 
113  $info['la']['original_crc'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
114  $offset += 4;
115 
116  // mikeØbevin*de
117  // Basically, the blocksize/seekevery are 61440/19 in La0.4 and 73728/16
118  // in earlier versions. A seekpoint is added every blocksize * seekevery
119  // samples, so 4 * int(totalSamples / (blockSize * seekEvery)) should
120  // give the number of bytes used for the seekpoints. Of course, if seeking
121  // is disabled, there are no seekpoints stored.
122  if ($info['la']['version'] >= 0.4) {
123  $info['la']['blocksize'] = 61440;
124  $info['la']['seekevery'] = 19;
125  } else {
126  $info['la']['blocksize'] = 73728;
127  $info['la']['seekevery'] = 16;
128  }
129 
130  $info['la']['seekpoint_count'] = 0;
131  if ($info['la']['flags']['seekable']) {
132  $info['la']['seekpoint_count'] = floor($info['la']['samples'] / ($info['la']['blocksize'] * $info['la']['seekevery']));
133 
134  for ($i = 0; $i < $info['la']['seekpoint_count']; $i++) {
135  $info['la']['seekpoints'][] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
136  $offset += 4;
137  }
138  }
139 
140  if ($info['la']['version'] >= 0.3) {
141 
142  // Following the main header information, the program outputs all of the
143  // seekpoints. Following these is what I called the 'footer start',
144  // i.e. the position immediately after the La audio data is finished.
145  $info['la']['footerstart'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
146  $offset += 4;
147 
148  if ($info['la']['footerstart'] > $info['filesize']) {
149  $this->warning('FooterStart value points to offset '.$info['la']['footerstart'].' which is beyond end-of-file ('.$info['filesize'].')');
150  $info['la']['footerstart'] = $info['filesize'];
151  }
152 
153  } else {
154 
155  // La v0.2 didn't have FooterStart value
156  $info['la']['footerstart'] = $info['avdataend'];
157 
158  }
159 
160  if ($info['la']['footerstart'] < $info['avdataend']) {
161  if ($RIFFtempfilename = tempnam(GETID3_TEMP_DIR, 'id3')) {
162  if ($RIFF_fp = fopen($RIFFtempfilename, 'w+b')) {
163  $RIFFdata = 'WAVE';
164  if ($info['la']['version'] == 0.2) {
165  $RIFFdata .= substr($rawdata, 12, 24);
166  } else {
167  $RIFFdata .= substr($rawdata, 16, 24);
168  }
169  if ($info['la']['footerstart'] < $info['avdataend']) {
170  $this->fseek($info['la']['footerstart']);
171  $RIFFdata .= $this->fread($info['avdataend'] - $info['la']['footerstart']);
172  }
173  $RIFFdata = 'RIFF'.getid3_lib::LittleEndian2String(strlen($RIFFdata), 4, false).$RIFFdata;
174  fwrite($RIFF_fp, $RIFFdata, strlen($RIFFdata));
175  fclose($RIFF_fp);
176 
177  $getid3_temp = new getID3();
178  $getid3_temp->openfile($RIFFtempfilename);
179  $getid3_riff = new getid3_riff($getid3_temp);
180  $getid3_riff->Analyze();
181 
182  if (empty($getid3_temp->info['error'])) {
183  $info['riff'] = $getid3_temp->info['riff'];
184  } else {
185  $this->warning('Error parsing RIFF portion of La file: '.implode($getid3_temp->info['error']));
186  }
187  unset($getid3_temp, $getid3_riff);
188  }
189  unlink($RIFFtempfilename);
190  }
191  }
192 
193  // $info['avdataoffset'] should be zero to begin with, but just in case it's not, include the addition anyway
194  $info['avdataend'] = $info['avdataoffset'] + $info['la']['footerstart'];
195  $info['avdataoffset'] = $info['avdataoffset'] + $offset;
196 
197  $info['la']['compression_ratio'] = (float) (($info['avdataend'] - $info['avdataoffset']) / $info['la']['uncompressed_size']);
198  $info['playtime_seconds'] = (float) ($info['la']['samples'] / $info['la']['sample_rate']) / $info['la']['channels'];
199  if ($info['playtime_seconds'] == 0) {
200  $this->error('Corrupt LA file: playtime_seconds == zero');
201  return false;
202  }
203 
204  $info['audio']['bitrate'] = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['playtime_seconds'];
205  //$info['audio']['codec'] = $info['la']['codec'];
206  $info['audio']['bits_per_sample'] = $info['la']['bits_per_sample'];
207  break;
208 
209  default:
210  if (substr($rawdata, $offset, 2) == 'LA') {
211  $this->error('This version of getID3() ['.$this->getid3->version().'] does not support LA version '.substr($rawdata, $offset + 2, 1).'.'.substr($rawdata, $offset + 3, 1).' which this appears to be - check http://getid3.sourceforge.net for updates.');
212  } else {
213  $this->error('Not a LA (Lossless-Audio) file');
214  }
215  return false;
216  break;
217  }
218 
219  $info['audio']['channels'] = $info['la']['channels'];
220  $info['audio']['sample_rate'] = (int) $info['la']['sample_rate'];
221  $info['audio']['encoder'] = 'LA v'.$info['la']['version'];
222 
223  return true;
224  }
225 
226 }
getid3_handler\error
error($text)
Definition: getid3.php:1752
getid3_handler\warning
warning($text)
Definition: getid3.php:1758
getid3_lib\LittleEndian2Int
static LittleEndian2Int($byteword, $signed=false)
Definition: getid3.lib.php:292
getid3_lib\IncludeDependency
static IncludeDependency($filename, $sourcefile, $DieOnFailure=false)
Definition: getid3.lib.php:1373
getid3_handler
Definition: getid3.php:1616
getid3_lib\PrintHexBytes
static PrintHexBytes($string, $hex=true, $spaces=true, $htmlencoding='UTF-8')
Definition: getid3.lib.php:18
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1683
getid3_la
Definition: module.audio.la.php:19
getid3_la\Analyze
Analyze()
Definition: module.audio.la.php:22
getid3_riff
Definition: module.audio-video.riff.php:30
$i
$i
Definition: disco.tpl.php:19
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1711
$info
$info
Definition: index.php:5