ILIAS  release_5-1 Revision 5.0.0-5477-g43f3e3fab5f
module.audio.flac.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.flac.php //
11// module for analyzing FLAC and OggFLAC audio files //
12// dependencies: module.audio.ogg.php //
13// ///
15
16
17getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.ogg.php', __FILE__, true);
18
19class getid3_flac
20{
21
22 function getid3_flac(&$fd, &$ThisFileInfo) {
23 // http://flac.sourceforge.net/format.html
24
25 fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);
26 $StreamMarker = fread($fd, 4);
27 if ($StreamMarker != 'fLaC') {
28 $ThisFileInfo['error'][] = 'Expecting "fLaC" at offset '.$ThisFileInfo['avdataoffset'].', found "'.$StreamMarker.'"';
29 return false;
30 }
31 $ThisFileInfo['fileformat'] = 'flac';
32 $ThisFileInfo['audio']['dataformat'] = 'flac';
33 $ThisFileInfo['audio']['bitrate_mode'] = 'vbr';
34 $ThisFileInfo['audio']['lossless'] = true;
35
36 return getid3_flac::FLACparseMETAdata($fd, $ThisFileInfo);
37 }
38
39
40 function FLACparseMETAdata(&$fd, &$ThisFileInfo) {
41
42 do {
43 $METAdataBlockOffset = ftell($fd);
44 $METAdataBlockHeader = fread($fd, 4);
45 $METAdataLastBlockFlag = (bool) (getid3_lib::BigEndian2Int(substr($METAdataBlockHeader, 0, 1)) & 0x80);
46 $METAdataBlockType = getid3_lib::BigEndian2Int(substr($METAdataBlockHeader, 0, 1)) & 0x7F;
47 $METAdataBlockLength = getid3_lib::BigEndian2Int(substr($METAdataBlockHeader, 1, 3));
48 $METAdataBlockTypeText = getid3_flac::FLACmetaBlockTypeLookup($METAdataBlockType);
49
50 if ($METAdataBlockLength < 0) {
51 $ThisFileInfo['error'][] = 'corrupt or invalid METADATA_BLOCK_HEADER.BLOCK_TYPE ('.$METAdataBlockType.') at offset '.$METAdataBlockOffset;
52 break;
53 }
54
55 $ThisFileInfo['flac'][$METAdataBlockTypeText]['raw'] = array();
56 $ThisFileInfo_flac_METAdataBlockTypeText_raw = &$ThisFileInfo['flac'][$METAdataBlockTypeText]['raw'];
57
58 $ThisFileInfo_flac_METAdataBlockTypeText_raw['offset'] = $METAdataBlockOffset;
59 $ThisFileInfo_flac_METAdataBlockTypeText_raw['last_meta_block'] = $METAdataLastBlockFlag;
60 $ThisFileInfo_flac_METAdataBlockTypeText_raw['block_type'] = $METAdataBlockType;
61 $ThisFileInfo_flac_METAdataBlockTypeText_raw['block_type_text'] = $METAdataBlockTypeText;
62 $ThisFileInfo_flac_METAdataBlockTypeText_raw['block_length'] = $METAdataBlockLength;
63 $ThisFileInfo_flac_METAdataBlockTypeText_raw['block_data'] = @fread($fd, $METAdataBlockLength);
64 $ThisFileInfo['avdataoffset'] = ftell($fd);
65
66 switch ($METAdataBlockTypeText) {
67
68 case 'STREAMINFO':
69 if (!getid3_flac::FLACparseSTREAMINFO($ThisFileInfo_flac_METAdataBlockTypeText_raw['block_data'], $ThisFileInfo)) {
70 return false;
71 }
72 break;
73
74 case 'PADDING':
75 // ignore
76 break;
77
78 case 'APPLICATION':
79 if (!getid3_flac::FLACparseAPPLICATION($ThisFileInfo_flac_METAdataBlockTypeText_raw['block_data'], $ThisFileInfo)) {
80 return false;
81 }
82 break;
83
84 case 'SEEKTABLE':
85 if (!getid3_flac::FLACparseSEEKTABLE($ThisFileInfo_flac_METAdataBlockTypeText_raw['block_data'], $ThisFileInfo)) {
86 return false;
87 }
88 break;
89
90 case 'VORBIS_COMMENT':
91 $OldOffset = ftell($fd);
92 fseek($fd, 0 - $METAdataBlockLength, SEEK_CUR);
93 getid3_ogg::ParseVorbisCommentsFilepointer($fd, $ThisFileInfo);
94 fseek($fd, $OldOffset, SEEK_SET);
95 break;
96
97 case 'CUESHEET':
98 if (!getid3_flac::FLACparseCUESHEET($ThisFileInfo_flac_METAdataBlockTypeText_raw['block_data'], $ThisFileInfo)) {
99 return false;
100 }
101 break;
102
103 default:
104 $ThisFileInfo['warning'][] = 'Unhandled METADATA_BLOCK_HEADER.BLOCK_TYPE ('.$METAdataBlockType.') at offset '.$METAdataBlockOffset;
105 break;
106 }
107
108 } while ($METAdataLastBlockFlag === false);
109
110
111 if (isset($ThisFileInfo['flac']['STREAMINFO'])) {
112 $ThisFileInfo['flac']['compressed_audio_bytes'] = $ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset'];
113 $ThisFileInfo['flac']['uncompressed_audio_bytes'] = $ThisFileInfo['flac']['STREAMINFO']['samples_stream'] * $ThisFileInfo['flac']['STREAMINFO']['channels'] * ($ThisFileInfo['flac']['STREAMINFO']['bits_per_sample'] / 8);
114 if ($ThisFileInfo['flac']['uncompressed_audio_bytes'] == 0) {
115 $ThisFileInfo['error'][] = 'Corrupt FLAC file: uncompressed_audio_bytes == zero';
116 return false;
117 }
118 $ThisFileInfo['flac']['compression_ratio'] = $ThisFileInfo['flac']['compressed_audio_bytes'] / $ThisFileInfo['flac']['uncompressed_audio_bytes'];
119 }
120
121 // set md5_data_source - built into flac 0.5+
122 if (isset($ThisFileInfo['flac']['STREAMINFO']['audio_signature'])) {
123
124 if ($ThisFileInfo['flac']['STREAMINFO']['audio_signature'] === str_repeat("\x00", 16)) {
125
126 $ThisFileInfo['warning'][] = 'FLAC STREAMINFO.audio_signature is null (known issue with libOggFLAC)';
127
128 } else {
129
130 $ThisFileInfo['md5_data_source'] = '';
131 $md5 = $ThisFileInfo['flac']['STREAMINFO']['audio_signature'];
132 for ($i = 0; $i < strlen($md5); $i++) {
133 $ThisFileInfo['md5_data_source'] .= str_pad(dechex(ord($md5{$i})), 2, '00', STR_PAD_LEFT);
134 }
135 if (!preg_match('/^[0-9a-f]{32}$/', $ThisFileInfo['md5_data_source'])) {
136 unset($ThisFileInfo['md5_data_source']);
137 }
138
139 }
140
141 }
142
143 $ThisFileInfo['audio']['bits_per_sample'] = $ThisFileInfo['flac']['STREAMINFO']['bits_per_sample'];
144 if ($ThisFileInfo['audio']['bits_per_sample'] == 8) {
145 // special case
146 // must invert sign bit on all data bytes before MD5'ing to match FLAC's calculated value
147 // MD5sum calculates on unsigned bytes, but FLAC calculated MD5 on 8-bit audio data as signed
148 $ThisFileInfo['warning'][] = 'FLAC calculates MD5 data strangely on 8-bit audio, so the stored md5_data_source value will not match the decoded WAV file';
149 }
150 if (!empty($ThisFileInfo['ogg']['vendor'])) {
151 $ThisFileInfo['audio']['encoder'] = $ThisFileInfo['ogg']['vendor'];
152 }
153
154 return true;
155 }
156
157 function FLACmetaBlockTypeLookup($blocktype) {
158 static $FLACmetaBlockTypeLookup = array();
159 if (empty($FLACmetaBlockTypeLookup)) {
160 $FLACmetaBlockTypeLookup[0] = 'STREAMINFO';
161 $FLACmetaBlockTypeLookup[1] = 'PADDING';
162 $FLACmetaBlockTypeLookup[2] = 'APPLICATION';
163 $FLACmetaBlockTypeLookup[3] = 'SEEKTABLE';
164 $FLACmetaBlockTypeLookup[4] = 'VORBIS_COMMENT';
165 $FLACmetaBlockTypeLookup[5] = 'CUESHEET';
166 }
167 return (isset($FLACmetaBlockTypeLookup[$blocktype]) ? $FLACmetaBlockTypeLookup[$blocktype] : 'reserved');
168 }
169
170 function FLACapplicationIDLookup($applicationid) {
171 static $FLACapplicationIDLookup = array();
172 if (empty($FLACapplicationIDLookup)) {
173 // http://flac.sourceforge.net/id.html
174 $FLACapplicationIDLookup[0x46746F6C] = 'flac-tools'; // 'Ftol'
175 $FLACapplicationIDLookup[0x46746F6C] = 'Sound Font FLAC'; // 'SFFL'
176 }
177 return (isset($FLACapplicationIDLookup[$applicationid]) ? $FLACapplicationIDLookup[$applicationid] : 'reserved');
178 }
179
180 function FLACparseSTREAMINFO($METAdataBlockData, &$ThisFileInfo) {
181 $offset = 0;
182 $ThisFileInfo['flac']['STREAMINFO']['min_block_size'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 2));
183 $offset += 2;
184 $ThisFileInfo['flac']['STREAMINFO']['max_block_size'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 2));
185 $offset += 2;
186 $ThisFileInfo['flac']['STREAMINFO']['min_frame_size'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 3));
187 $offset += 3;
188 $ThisFileInfo['flac']['STREAMINFO']['max_frame_size'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 3));
189 $offset += 3;
190
191 $SampleRateChannelsSampleBitsStreamSamples = getid3_lib::BigEndian2Bin(substr($METAdataBlockData, $offset, 8));
192 $ThisFileInfo['flac']['STREAMINFO']['sample_rate'] = getid3_lib::Bin2Dec(substr($SampleRateChannelsSampleBitsStreamSamples, 0, 20));
193 $ThisFileInfo['flac']['STREAMINFO']['channels'] = getid3_lib::Bin2Dec(substr($SampleRateChannelsSampleBitsStreamSamples, 20, 3)) + 1;
194 $ThisFileInfo['flac']['STREAMINFO']['bits_per_sample'] = getid3_lib::Bin2Dec(substr($SampleRateChannelsSampleBitsStreamSamples, 23, 5)) + 1;
195 $ThisFileInfo['flac']['STREAMINFO']['samples_stream'] = getid3_lib::Bin2Dec(substr($SampleRateChannelsSampleBitsStreamSamples, 28, 36));
196 $offset += 8;
197
198 $ThisFileInfo['flac']['STREAMINFO']['audio_signature'] = substr($METAdataBlockData, $offset, 16);
199 $offset += 16;
200
201 if (!empty($ThisFileInfo['flac']['STREAMINFO']['sample_rate'])) {
202
203 $ThisFileInfo['audio']['bitrate_mode'] = 'vbr';
204 $ThisFileInfo['audio']['sample_rate'] = $ThisFileInfo['flac']['STREAMINFO']['sample_rate'];
205 $ThisFileInfo['audio']['channels'] = $ThisFileInfo['flac']['STREAMINFO']['channels'];
206 $ThisFileInfo['audio']['bits_per_sample'] = $ThisFileInfo['flac']['STREAMINFO']['bits_per_sample'];
207 $ThisFileInfo['playtime_seconds'] = $ThisFileInfo['flac']['STREAMINFO']['samples_stream'] / $ThisFileInfo['flac']['STREAMINFO']['sample_rate'];
208 $ThisFileInfo['audio']['bitrate'] = (($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) * 8) / $ThisFileInfo['playtime_seconds'];
209
210 } else {
211
212 $ThisFileInfo['error'][] = 'Corrupt METAdata block: STREAMINFO';
213 return false;
214
215 }
216 return true;
217 }
218
219
220 function FLACparseAPPLICATION($METAdataBlockData, &$ThisFileInfo) {
221 $offset = 0;
222 $ApplicationID = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 4));
223 $offset += 4;
224 $ThisFileInfo['flac']['APPLICATION'][$ApplicationID]['name'] = getid3_flac::FLACapplicationIDLookup($ApplicationID);
225 $ThisFileInfo['flac']['APPLICATION'][$ApplicationID]['data'] = substr($METAdataBlockData, $offset);
226 $offset = $METAdataBlockLength;
227
228 return true;
229 }
230
231
232 function FLACparseSEEKTABLE($METAdataBlockData, &$ThisFileInfo) {
233 $offset = 0;
234 $METAdataBlockLength = strlen($METAdataBlockData);
235 $placeholderpattern = str_repeat("\xFF", 8);
236 while ($offset < $METAdataBlockLength) {
237 $SampleNumberString = substr($METAdataBlockData, $offset, 8);
238 $offset += 8;
239 if ($SampleNumberString == $placeholderpattern) {
240
241 // placeholder point
242 @$ThisFileInfo['flac']['SEEKTABLE']['placeholders']++;
243 $offset += 10;
244
245 } else {
246
247 $SampleNumber = getid3_lib::BigEndian2Int($SampleNumberString);
248 $ThisFileInfo['flac']['SEEKTABLE'][$SampleNumber]['offset'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 8));
249 $offset += 8;
250 $ThisFileInfo['flac']['SEEKTABLE'][$SampleNumber]['samples'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 2));
251 $offset += 2;
252
253 }
254 }
255 return true;
256 }
257
258 function FLACparseCUESHEET($METAdataBlockData, &$ThisFileInfo) {
259 $offset = 0;
260 $ThisFileInfo['flac']['CUESHEET']['media_catalog_number'] = trim(substr($METAdataBlockData, $offset, 128), "\0");
261 $offset += 128;
262 $ThisFileInfo['flac']['CUESHEET']['lead_in_samples'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 8));
263 $offset += 8;
264 $ThisFileInfo['flac']['CUESHEET']['flags']['is_cd'] = (bool) (getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1)) & 0x80);
265 $offset += 1;
266
267 $offset += 258; // reserved
268
269 $ThisFileInfo['flac']['CUESHEET']['number_tracks'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1));
270 $offset += 1;
271
272 for ($track = 0; $track < $ThisFileInfo['flac']['CUESHEET']['number_tracks']; $track++) {
273 $TrackSampleOffset = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 8));
274 $offset += 8;
275 $TrackNumber = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1));
276 $offset += 1;
277
278 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['sample_offset'] = $TrackSampleOffset;
279
280 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['isrc'] = substr($METAdataBlockData, $offset, 12);
281 $offset += 12;
282
283 $TrackFlagsRaw = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1));
284 $offset += 1;
285 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['flags']['is_audio'] = (bool) ($TrackFlagsRaw & 0x80);
286 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['flags']['pre_emphasis'] = (bool) ($TrackFlagsRaw & 0x40);
287
288 $offset += 13; // reserved
289
290 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['index_points'] = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1));
291 $offset += 1;
292
293 for ($index = 0; $index < $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['index_points']; $index++) {
294 $IndexSampleOffset = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 8));
295 $offset += 8;
296 $IndexNumber = getid3_lib::BigEndian2Int(substr($METAdataBlockData, $offset, 1));
297 $offset += 1;
298
299 $offset += 3; // reserved
300
301 $ThisFileInfo['flac']['CUESHEET']['tracks'][$TrackNumber]['indexes'][$IndexNumber] = $IndexSampleOffset;
302 }
303 }
304 return true;
305 }
306
307}
308
309?>
getid3_flac
@tutorial http://flac.sourceforge.net/format.html
Definition: module.audio.flac.php:20
getid3_flac\FLACparseSTREAMINFO
FLACparseSTREAMINFO($METAdataBlockData, &$ThisFileInfo)
Definition: module.audio.flac.php:180
getid3_flac\FLACparseCUESHEET
FLACparseCUESHEET($METAdataBlockData, &$ThisFileInfo)
Definition: module.audio.flac.php:258
getid3_flac\FLACparseMETAdata
FLACparseMETAdata(&$fd, &$ThisFileInfo)
Definition: module.audio.flac.php:40
getid3_flac\FLACparseAPPLICATION
FLACparseAPPLICATION($METAdataBlockData, &$ThisFileInfo)
Definition: module.audio.flac.php:220
getid3_flac\FLACmetaBlockTypeLookup
FLACmetaBlockTypeLookup($blocktype)
Definition: module.audio.flac.php:157
getid3_flac\FLACparseSEEKTABLE
FLACparseSEEKTABLE($METAdataBlockData, &$ThisFileInfo)
Definition: module.audio.flac.php:232
getid3_flac\getid3_flac
getid3_flac(&$fd, &$ThisFileInfo)
Definition: module.audio.flac.php:22
getid3_flac\FLACapplicationIDLookup
FLACapplicationIDLookup($applicationid)
Definition: module.audio.flac.php:170
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1697
getid3_handler\ftell
ftell()
Definition: getid3.php:1678
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1685
getid3_lib\BigEndian2Bin
BigEndian2Bin($byteword)
Definition: getid3.lib.php:271
getid3_lib\IncludeDependency
IncludeDependency($filename, $sourcefile, $DieOnFailure=false)
Definition: getid3.lib.php:1301
getid3_lib\BigEndian2Int
BigEndian2Int($byteword, $synchsafe=false, $signed=false)
Definition: getid3.lib.php:234
getid3_lib\Bin2Dec
Bin2Dec($binstring, $signed=false)
Definition: getid3.lib.php:316
getid3_ogg\ParseVorbisCommentsFilepointer
ParseVorbisCommentsFilepointer(&$fd, &$ThisFileInfo)
Definition: module.audio.ogg.php:313