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
17getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);
18
19class 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}
php
An exception for terminatinating execution or to throw for unit testing.
getid3_handler
Definition: getid3.php:1616
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1711
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1683
getid3_handler\warning
warning($text)
Definition: getid3.php:1758
getid3_handler\error
error($text)
Definition: getid3.php:1752
getid3_la
Definition: module.audio.la.php:20
getid3_la\Analyze
Analyze()
Definition: module.audio.la.php:22
getid3_lib\PrintHexBytes
static PrintHexBytes($string, $hex=true, $spaces=true, $htmlencoding='UTF-8')
Definition: getid3.lib.php:18
getid3_lib\LittleEndian2Int
static LittleEndian2Int($byteword, $signed=false)
Definition: getid3.lib.php:292
getid3_lib\IncludeDependency
static IncludeDependency($filename, $sourcefile, $DieOnFailure=false)
Definition: getid3.lib.php:1373
getid3_riff
Definition: module.audio-video.riff.php:30
$i
$i
Definition: disco.tpl.php:19
$info
$info
Definition: index.php:5