ILIAS  release_5-1 Revision 5.0.0-5477-g43f3e3fab5f
module.audio.la.php
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1<?php
4// available at http://getid3.sourceforge.net //
5// or http://www.getid3.org //
7// See readme.txt for more details //
9// //
10// module.audio.la.php //
11// module for analyzing LA audio files //
12// dependencies: module.audio.riff.php //
13// ///
15
16getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);
17
18class getid3_la
19{
20
21 function getid3_la(&$fd, &$ThisFileInfo) {
22 $offset = 0;
23 fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);
24 $rawdata = fread($fd, GETID3_FREAD_BUFFER_SIZE);
25
26 switch (substr($rawdata, $offset, 4)) {
27 case 'LA02':
28 case 'LA03':
29 case 'LA04':
30 $ThisFileInfo['fileformat'] = 'la';
31 $ThisFileInfo['audio']['dataformat'] = 'la';
32 $ThisFileInfo['audio']['lossless'] = true;
33
34 $ThisFileInfo['la']['version_major'] = (int) substr($rawdata, $offset + 2, 1);
35 $ThisFileInfo['la']['version_minor'] = (int) substr($rawdata, $offset + 3, 1);
36 $ThisFileInfo['la']['version'] = (float) $ThisFileInfo['la']['version_major'] + ($ThisFileInfo['la']['version_minor'] / 10);
37 $offset += 4;
38
39 $ThisFileInfo['la']['uncompressed_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
40 $offset += 4;
41 if ($ThisFileInfo['la']['uncompressed_size'] == 0) {
42 $ThisFileInfo['error'][] = 'Corrupt LA file: uncompressed_size == zero';
43 return false;
44 }
45
46 $WAVEchunk = substr($rawdata, $offset, 4);
47 if ($WAVEchunk !== 'WAVE') {
48 $ThisFileInfo['error'][] = 'Expected "WAVE" ('.getid3_lib::PrintHexBytes('WAVE').') at offset '.$offset.', found "'.$WAVEchunk.'" ('.getid3_lib::PrintHexBytes($WAVEchunk).') instead.';
49 return false;
50 }
51 $offset += 4;
52
53 $ThisFileInfo['la']['fmt_size'] = 24;
54 if ($ThisFileInfo['la']['version'] >= 0.3) {
55
56 $ThisFileInfo['la']['fmt_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
57 $ThisFileInfo['la']['header_size'] = 49 + $ThisFileInfo['la']['fmt_size'] - 24;
58 $offset += 4;
59
60 } else {
61
62 // version 0.2 didn't support additional data blocks
63 $ThisFileInfo['la']['header_size'] = 41;
64
65 }
66
67 $fmt_chunk = substr($rawdata, $offset, 4);
68 if ($fmt_chunk !== 'fmt ') {
69 $ThisFileInfo['error'][] = 'Expected "fmt " ('.getid3_lib::PrintHexBytes('fmt ').') at offset '.$offset.', found "'.$fmt_chunk.'" ('.getid3_lib::PrintHexBytes($fmt_chunk).') instead.';
70 return false;
71 }
72 $offset += 4;
73 $fmt_size = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
74 $offset += 4;
75
76 $ThisFileInfo['la']['raw']['format'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
77 $offset += 2;
78
79 $ThisFileInfo['la']['channels'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
80 $offset += 2;
81 if ($ThisFileInfo['la']['channels'] == 0) {
82 $ThisFileInfo['error'][] = 'Corrupt LA file: channels == zero';
83 return false;
84 }
85
86 $ThisFileInfo['la']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
87 $offset += 4;
88 if ($ThisFileInfo['la']['sample_rate'] == 0) {
89 $ThisFileInfo['error'][] = 'Corrupt LA file: sample_rate == zero';
90 return false;
91 }
92
93 $ThisFileInfo['la']['bytes_per_second'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
94 $offset += 4;
95 $ThisFileInfo['la']['bytes_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
96 $offset += 2;
97 $ThisFileInfo['la']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
98 $offset += 2;
99
100 $ThisFileInfo['la']['samples'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
101 $offset += 4;
102
103 $ThisFileInfo['la']['raw']['flags'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 1));
104 $offset += 1;
105 $ThisFileInfo['la']['flags']['seekable'] = (bool) ($ThisFileInfo['la']['raw']['flags'] & 0x01);
106 if ($ThisFileInfo['la']['version'] >= 0.4) {
107 $ThisFileInfo['la']['flags']['high_compression'] = (bool) ($ThisFileInfo['la']['raw']['flags'] & 0x02);
108 }
109
110 $ThisFileInfo['la']['original_crc'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
111 $offset += 4;
112
113 // mikeØbevin*de
114 // Basically, the blocksize/seekevery are 61440/19 in La0.4 and 73728/16
115 // in earlier versions. A seekpoint is added every blocksize * seekevery
116 // samples, so 4 * int(totalSamples / (blockSize * seekEvery)) should
117 // give the number of bytes used for the seekpoints. Of course, if seeking
118 // is disabled, there are no seekpoints stored.
119 if ($ThisFileInfo['la']['version'] >= 0.4) {
120 $ThisFileInfo['la']['blocksize'] = 61440;
121 $ThisFileInfo['la']['seekevery'] = 19;
122 } else {
123 $ThisFileInfo['la']['blocksize'] = 73728;
124 $ThisFileInfo['la']['seekevery'] = 16;
125 }
126
127 $ThisFileInfo['la']['seekpoint_count'] = 0;
128 if ($ThisFileInfo['la']['flags']['seekable']) {
129 $ThisFileInfo['la']['seekpoint_count'] = floor($ThisFileInfo['la']['samples'] / ($ThisFileInfo['la']['blocksize'] * $ThisFileInfo['la']['seekevery']));
130
131 for ($i = 0; $i < $ThisFileInfo['la']['seekpoint_count']; $i++) {
132 $ThisFileInfo['la']['seekpoints'][] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
133 $offset += 4;
134 }
135 }
136
137 if ($ThisFileInfo['la']['version'] >= 0.3) {
138
139 // Following the main header information, the program outputs all of the
140 // seekpoints. Following these is what I called the 'footer start',
141 // i.e. the position immediately after the La audio data is finished.
142 $ThisFileInfo['la']['footerstart'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
143 $offset += 4;
144
145 if ($ThisFileInfo['la']['footerstart'] > $ThisFileInfo['filesize']) {
146 $ThisFileInfo['warning'][] = 'FooterStart value points to offset '.$ThisFileInfo['la']['footerstart'].' which is beyond end-of-file ('.$ThisFileInfo['filesize'].')';
147 $ThisFileInfo['la']['footerstart'] = $ThisFileInfo['filesize'];
148 }
149
150 } else {
151
152 // La v0.2 didn't have FooterStart value
153 $ThisFileInfo['la']['footerstart'] = $ThisFileInfo['avdataend'];
154
155 }
156
157 if ($ThisFileInfo['la']['footerstart'] < $ThisFileInfo['avdataend']) {
158 if ($RIFFtempfilename = tempnam('*', 'id3')) {
159 if ($RIFF_fp = fopen($RIFFtempfilename, 'w+b')) {
160 $RIFFdata = 'WAVE';
161 if ($ThisFileInfo['la']['version'] == 0.2) {
162 $RIFFdata .= substr($rawdata, 12, 24);
163 } else {
164 $RIFFdata .= substr($rawdata, 16, 24);
165 }
166 if ($ThisFileInfo['la']['footerstart'] < $ThisFileInfo['avdataend']) {
167 fseek($fd, $ThisFileInfo['la']['footerstart'], SEEK_SET);
168 $RIFFdata .= fread($fd, $ThisFileInfo['avdataend'] - $ThisFileInfo['la']['footerstart']);
169 }
170 $RIFFdata = 'RIFF'.getid3_lib::LittleEndian2String(strlen($RIFFdata), 4, false).$RIFFdata;
171 fwrite($RIFF_fp, $RIFFdata, strlen($RIFFdata));
172 $dummy = $ThisFileInfo;
173 $dummy['filesize'] = strlen($RIFFdata);
174 $dummy['avdataoffset'] = 0;
175 $dummy['avdataend'] = $dummy['filesize'];
176
177 $riff = new getid3_riff($RIFF_fp, $dummy);
178 if (empty($dummy['error'])) {
179 $ThisFileInfo['riff'] = $dummy['riff'];
180 } else {
181 $ThisFileInfo['warning'][] = 'Error parsing RIFF portion of La file: '.implode($dummy['error']);
182 }
183 unset($dummy);
184 fclose($RIFF_fp);
185 }
186 unlink($RIFFtempfilename);
187 }
188 }
189
190 // $ThisFileInfo['avdataoffset'] should be zero to begin with, but just in case it's not, include the addition anyway
191 $ThisFileInfo['avdataend'] = $ThisFileInfo['avdataoffset'] + $ThisFileInfo['la']['footerstart'];
192 $ThisFileInfo['avdataoffset'] = $ThisFileInfo['avdataoffset'] + $offset;
193
194 //$ThisFileInfo['la']['codec'] = RIFFwFormatTagLookup($ThisFileInfo['la']['raw']['format']);
195 $ThisFileInfo['la']['compression_ratio'] = (float) (($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) / $ThisFileInfo['la']['uncompressed_size']);
196 $ThisFileInfo['playtime_seconds'] = (float) ($ThisFileInfo['la']['samples'] / $ThisFileInfo['la']['sample_rate']) / $ThisFileInfo['la']['channels'];
197 if ($ThisFileInfo['playtime_seconds'] == 0) {
198 $ThisFileInfo['error'][] = 'Corrupt LA file: playtime_seconds == zero';
199 return false;
200 }
201
202 $ThisFileInfo['audio']['bitrate'] = ($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) * 8 / $ThisFileInfo['playtime_seconds'];
203 //$ThisFileInfo['audio']['codec'] = $ThisFileInfo['la']['codec'];
204 $ThisFileInfo['audio']['bits_per_sample'] = $ThisFileInfo['la']['bits_per_sample'];
205 break;
206
207 default:
208 if (substr($rawdata, $offset, 2) == 'LA') {
209 $ThisFileInfo['error'][] = 'This version of getID3() (v'.GETID3_VERSION.') doesn\'t support LA version '.substr($rawdata, $offset + 2, 1).'.'.substr($rawdata, $offset + 3, 1).' which this appears to be - check http://getid3.sourceforge.net for updates.';
210 } else {
211 $ThisFileInfo['error'][] = 'Not a LA (Lossless-Audio) file';
212 }
213 return false;
214 break;
215 }
216
217 $ThisFileInfo['audio']['channels'] = $ThisFileInfo['la']['channels'];
218 $ThisFileInfo['audio']['sample_rate'] = (int) $ThisFileInfo['la']['sample_rate'];
219 $ThisFileInfo['audio']['encoder'] = 'LA v'.$ThisFileInfo['la']['version'];
220
221 return true;
222 }
223
224}
225
226
227?>
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1697
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1685
getid3_la
Definition: module.audio.la.php:19
getid3_la\getid3_la
getid3_la(&$fd, &$ThisFileInfo)
Definition: module.audio.la.php:21
getid3_lib\LittleEndian2Int
LittleEndian2Int($byteword, $signed=false)
Definition: getid3.lib.php:266
getid3_lib\IncludeDependency
IncludeDependency($filename, $sourcefile, $DieOnFailure=false)
Definition: getid3.lib.php:1301
getid3_lib\PrintHexBytes
PrintHexBytes($string, $hex=true, $spaces=true, $htmlsafe=true)
Definition: getid3.lib.php:17
getid3_riff
Definition: module.audio-video.riff.php:22
GETID3_FREAD_BUFFER_SIZE
const GETID3_FREAD_BUFFER_SIZE
Definition: getid3.php:14