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1
7
8 package org.jboss.media.format.audio.oggvorbis;
9
10 import java.io.BufferedInputStream  ;
11 import java.io.FileInputStream ;
12 import java.io.IOException ;
13 import java.io.InputStream ;
14 import java.util.Arrays ;
15 import java.util.Hashtable ;
16 import java.util.Iterator ;
17 import java.util.Set ;
18 import java.util.Vector ;
19
20
30 class VorbisInfo
31 {
32 private int channels;
34 private long rate = 0;
35 private long bitrate_upper;
36 private long bitrate_nominal;
37 private long bitrate_lower;
38
39 String vendor;
41 int comments = 0;
42 Hashtable comment;
43
44 private long[] crc_lookup = new long[256];
46 private int crc_ready = 0;
47
48 private byte[] header;
50 private byte[] packet;
51
52
56 public VorbisInfo(InputStream s) throws IOException
57 {
58
59 for (int i = 0; i < 256; i++)
60 crc_lookup[i] = _ogg_crc_entry(i);
61
62 fetch_header_and_packet(s);
63 interpret_header_packet();
64
65 fetch_header_and_packet(s);
66 interpret_header_packet();
67 }
68
69
73 public int getChannels()
74 {
75 return channels;
76 }
77
78
82 public long getRate()
83 {
84 return rate;
85 }
86
87
91 public long getBitrate()
92 {
93 return bitrate_nominal;
94 }
95
96
113 public Vector getComments(String field)
114 {
115 return (Vector ) comment.get(field.toLowerCase());
116 }
117
118
122 public Set getFields()
123 {
124 return comment.keySet();
125 }
126
127 private void fetch_header_and_packet(InputStream s) throws IOException
128 {
129 byte[] head = new byte[27];
131 int bytes = s.read(head);
132 if (bytes < 27)
134 throw new IOException ("Not enough bytes in header");
135
136 if (!"OggS".equals(new String (head, 0, 4)))
137 throw new IOException ("Not a valid Ogg Vorbis file");
138
139 int headerbytes = (touint(head[26])) + 27;
140
142 byte[] head_rest = new byte[touint(head[26])]; bytes += s.read(head_rest);
145 header = new byte[headerbytes];
147 Arrays.fill(header, (byte) 0);
148
149 System.arraycopy(head, 0, header, 0, 27);
151 System.arraycopy(head_rest, 0, header, 27, headerbytes - 27);
152
153 if (bytes < headerbytes)
154 {
155 String error =
156 "Error reading vorbis file: "
157 + "Not enough bytes for header + seg table";
158 throw new IOException (error);
159 }
160
161 int bodybytes = 0;
162 for (int i = 0; i < header[26]; i++)
163 bodybytes += touint(header[27 + i]);
164
166 packet = new byte[bodybytes];
167 Arrays.fill(packet, (byte) 0);
168 bytes += s.read(packet);
169
171 if (bytes < headerbytes + bodybytes)
172 {
173 String error =
174 "Error reading vorbis file: "
175 + "Not enough bytes for header + body";
176 throw new IOException (error);
177 }
178
179 byte[] oldsum = new byte[4];
180 System.arraycopy(header, 22, oldsum, 0, 4); Arrays.fill(header, 22, 22 + 4, (byte) 0);
182
184 byte[] newsum = checksum();
185 if (!(new String (oldsum)).equals(new String (newsum)))
186 {
187 System.err.println("checksum failed");
188 System.err.println(
189 "old checksum: "
190 + oldsum[0]
191 + "|"
192 + oldsum[1]
193 + "|"
194 + oldsum[2]
195 + "|"
196 + oldsum[3]);
197 System.err.println(
198 "new checksum: "
199 + newsum[0]
200 + "|"
201 + newsum[1]
202 + "|"
203 + newsum[2]
204 + "|"
205 + newsum[3]);
206 }
207 }
208
209 private void interpret_header_packet() throws IOException
210 {
211 byte packet_type = packet[0];
212 switch (packet_type)
213 {
214 case 1 :
215 if (rate != 0)
217 throw new IOException ("Invalid vorbis file: info already fetched");
218 fetch_info_info();
219 break;
220 case 3 :
221 if (rate == 0)
223 throw new IOException ("Invalid vorbis file: header not complete");
224 fetch_comment_info();
225 break;
226 case 5 :
227 throw new IOException ("Invalid vorbis file: header not complete");
228 default :
229 throw new IOException ("Invalid vorbis file: bad packet header");
230 }
231 }
232
233
236 private void fetch_info_info() throws IOException
237 {
238 int dataptr = 1;
241 String str = new String (packet, dataptr, 6);
242 dataptr += 6;
243 if (!"vorbis".equals(str))
244 throw new IOException ("Not a vorbis header");
245 dataptr += 4;
247 channels = packet[dataptr++];
249 rate = toulong(read32(packet, dataptr));
250 dataptr += 4;
252 bitrate_upper = toulong(read32(packet, dataptr));
253 dataptr += 4;
255 bitrate_nominal = toulong(read32(packet, dataptr));
256 dataptr += 4;
258 bitrate_lower = toulong(read32(packet, dataptr));
259 dataptr += 4;
261 dataptr++;
263 byte eop = packet[dataptr++];
264 if (eop != 1)
265 throw new IOException ("End of packet expected but not found");
266 }
267
268 private void fetch_comment_info() throws IOException
269 {
270 int dataptr = 1;
271
272 String str = new String (packet, dataptr, 6);
273 dataptr += 6;
274 if (!"vorbis".equals(str))
275 throw new IOException ("Not a vorbis header");
276
277 comment = new Hashtable ();
278
279 long len = toulong(read32(packet, dataptr));
280 dataptr += 4;
282
283
292 vendor = new String (packet, dataptr, (int) len);
293 dataptr += len;
294
295 comments = (int) toulong(read32(packet, dataptr));
297 dataptr += 4;
298
299 for (int i = 0; i < comments; i++)
300 {
301
302 len = toulong(read32(packet, dataptr));
304 dataptr += 4;
305 String cmnt = new String (packet, dataptr, (int) len);
307 dataptr += len;
308
309 String name = cmnt.substring(0, cmnt.indexOf('='));
311 String value = cmnt.substring(cmnt.indexOf('=') + 1);
312 if (comment.containsKey(name))
313 {
314 Vector tmp = (Vector ) comment.get(name.toLowerCase());
315 tmp.add(value);
316 }
317 else
318 {
319 Vector tmp = new Vector ();
320 tmp.add(value);
321 comment.put(name.toLowerCase(), tmp);
322 }
323 }
324 }
325
326 private int read32(byte[] data, int ptr)
327 {
328 int val = 0;
329 val = (touint(data[ptr]) & 0x000000ff);
330 val |= ((touint(data[ptr + 1]) << 8) & 0x0000ff00);
331 val |= ((touint(data[ptr + 2]) << 16) & 0x00ff0000);
332 val |= ((touint(data[ptr + 3]) << 24) & 0xff000000);
333 return val;
334 }
335
336 private byte[] checksum()
337 {
338 long crc_reg = 0;
339
340 for (int i = 0; i < header.length; i++)
341 {
342 int tmp = (int) (((crc_reg >>> 24) & 0xff) ^ touint(header[i]));
343 crc_reg = (crc_reg << 8) ^ crc_lookup[tmp];
344 crc_reg &= 0xffffffff;
345 }
346 for (int i = 0; i < packet.length; i++)
347 {
348 int tmp = (int) (((crc_reg >>> 24) & 0xff) ^ touint(packet[i]));
349 crc_reg = (crc_reg << 8) ^ crc_lookup[tmp];
350 crc_reg &= 0xffffffff;
351 }
352
353 byte[] sum = new byte[4];
354 sum[0] = (byte) (crc_reg & 0xffL);
355 sum[1] = (byte) ((crc_reg >>> 8) & 0xffL);
356 sum[2] = (byte) ((crc_reg >>> 16) & 0xffL);
357 sum[3] = (byte) ((crc_reg >>> 24) & 0xffL);
358
359 return sum;
360 }
361
362 private long _ogg_crc_entry(long index)
363 {
364 long r;
365
366 r = index << 24;
367 for (int i = 0; i < 8; i++)
368 {
369 if ((r & 0x80000000L) != 0)
370 {
371 r = (r << 1) ^ 0x04c11db7L;
372 }
373 else
374 {
375 r <<= 1;
376 }
377 }
378 return (r & 0xffffffff);
379 }
380
381 private long toulong(int n)
382 {
383 return (n & 0xffffffffL);
384 }
385
386 private int touint(byte n)
387 {
388 return (n & 0xff);
389 }
390
391
395 public String toString()
396 {
397
398 String str = "";
399
400 str += channels + " channels at " + rate + "Hz\n";
401 str += bitrate_nominal / 1000 + "kbps (average bitrate)\n";
402
403 Iterator fields = comment.keySet().iterator();
404 while (fields.hasNext())
405 {
406 String name = (String ) fields.next();
407 Vector values = (Vector ) comment.get(name);
408 Iterator vi = values.iterator();
409 str += name + "=";
410 boolean dumb = false;
411 while (vi.hasNext())
412 {
413 if (dumb)
414 str += ", ";
415 str += vi.next();
416 dumb = true;
417 }
418 str += "\n";
419 }
420
421 return str;
422 }
423
424 static void main(String [] args) throws Exception
426 {
427 if (args.length != 1)
428 {
429 System.err.println("usage:\tjava VorbisInfo <ogg vorbis file>");
430 System.exit(1);
431 }
432 BufferedInputStream b =
433 new BufferedInputStream (new FileInputStream (args[0]));
434 VorbisInfo vi = new VorbisInfo(b);
435 System.out.println("\n" + vi);
436
437 b.close();
438 }
439
440 public Hashtable getComments() {
442 return comment;
443 }
444 } |
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