ILIAS  release_5-1 Revision 5.0.0-5477-g43f3e3fab5f
module.audio.tta.php
Go to the documentation of this file.
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.tta.php //
11// module for analyzing TTA Audio files //
12// dependencies: NONE //
13// ///
15
16
18{
19
20 function getid3_tta(&$fd, &$ThisFileInfo) {
21
22 $ThisFileInfo['fileformat'] = 'tta';
23 $ThisFileInfo['audio']['dataformat'] = 'tta';
24 $ThisFileInfo['audio']['lossless'] = true;
25 $ThisFileInfo['audio']['bitrate_mode'] = 'vbr';
26
27 fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);
28 $ttaheader = fread($fd, 26);
29
30 $ThisFileInfo['tta']['magic'] = substr($ttaheader, 0, 3);
31 if ($ThisFileInfo['tta']['magic'] != 'TTA') {
32 $ThisFileInfo['error'][] = 'Expecting "TTA" at offset '.$ThisFileInfo['avdataoffset'].', found "'.$ThisFileInfo['tta']['magic'].'"';
33 unset($ThisFileInfo['fileformat']);
34 unset($ThisFileInfo['audio']);
35 unset($ThisFileInfo['tta']);
36 return false;
37 }
38
39 switch ($ttaheader{3}) {
40 case "\x01": // TTA v1.x
41 case "\x02": // TTA v1.x
42 case "\x03": // TTA v1.x
43 // "It was the demo-version of the TTA encoder. There is no released format with such header. TTA encoder v1 is not supported about a year."
44 $ThisFileInfo['tta']['major_version'] = 1;
45 $ThisFileInfo['avdataoffset'] += 16;
46
47 $ThisFileInfo['tta']['compression_level'] = ord($ttaheader{3});
48 $ThisFileInfo['tta']['channels'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 4, 2));
49 $ThisFileInfo['tta']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 6, 2));
50 $ThisFileInfo['tta']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 8, 4));
51 $ThisFileInfo['tta']['samples_per_channel'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 12, 4));
52
53 $ThisFileInfo['audio']['encoder_options'] = '-e'.$ThisFileInfo['tta']['compression_level'];
54 $ThisFileInfo['playtime_seconds'] = $ThisFileInfo['tta']['samples_per_channel'] / $ThisFileInfo['tta']['sample_rate'];
55 break;
56
57 case '2': // TTA v2.x
58 // "I have hurried to release the TTA 2.0 encoder. Format documentation is removed from our site. This format still in development. Please wait the TTA2 format, encoder v4."
59 $ThisFileInfo['tta']['major_version'] = 2;
60 $ThisFileInfo['avdataoffset'] += 20;
61
62 $ThisFileInfo['tta']['compression_level'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 4, 2));
63 $ThisFileInfo['tta']['audio_format'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 6, 2));
64 $ThisFileInfo['tta']['channels'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 8, 2));
65 $ThisFileInfo['tta']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 10, 2));
66 $ThisFileInfo['tta']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 12, 4));
67 $ThisFileInfo['tta']['data_length'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 16, 4));
68
69 $ThisFileInfo['audio']['encoder_options'] = '-e'.$ThisFileInfo['tta']['compression_level'];
70 $ThisFileInfo['playtime_seconds'] = $ThisFileInfo['tta']['data_length'] / $ThisFileInfo['tta']['sample_rate'];
71 break;
72
73 case '1': // TTA v3.x
74 // "This is a first stable release of the TTA format. It will be supported by the encoders v3 or higher."
75 $ThisFileInfo['tta']['major_version'] = 3;
76 $ThisFileInfo['avdataoffset'] += 26;
77
78 $ThisFileInfo['tta']['audio_format'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 4, 2)); // getid3_riff::RIFFwFormatTagLookup()
79 $ThisFileInfo['tta']['channels'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 6, 2));
80 $ThisFileInfo['tta']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 8, 2));
81 $ThisFileInfo['tta']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 10, 4));
82 $ThisFileInfo['tta']['data_length'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 14, 4));
83 $ThisFileInfo['tta']['crc32_footer'] = substr($ttaheader, 18, 4);
84 $ThisFileInfo['tta']['seek_point'] = getid3_lib::LittleEndian2Int(substr($ttaheader, 22, 4));
85
86 $ThisFileInfo['playtime_seconds'] = $ThisFileInfo['tta']['data_length'] / $ThisFileInfo['tta']['sample_rate'];
87 break;
88
89 default:
90 $ThisFileInfo['error'][] = 'This version of getID3() only knows how to handle TTA v1 and v2 - it may not work correctly with this file which appears to be TTA v'.$ttaheader{3};
91 return false;
92 break;
93 }
94
95 $ThisFileInfo['audio']['encoder'] = 'TTA v'.$ThisFileInfo['tta']['major_version'];
96 $ThisFileInfo['audio']['bits_per_sample'] = $ThisFileInfo['tta']['bits_per_sample'];
97 $ThisFileInfo['audio']['sample_rate'] = $ThisFileInfo['tta']['sample_rate'];
98 $ThisFileInfo['audio']['channels'] = $ThisFileInfo['tta']['channels'];
99 $ThisFileInfo['audio']['bitrate'] = (($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) * 8) / $ThisFileInfo['playtime_seconds'];
100
101 return true;
102 }
103
104}
105
106
107?>
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1697
fread($bytes)
Definition: getid3.php:1685
LittleEndian2Int($byteword, $signed=false)
Definition: getid3.lib.php:266
getID3() by James Heinrich info@getid3.org //
getid3_tta(&$fd, &$ThisFileInfo)