Libav
ape.c
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1 /*
2  * Monkey's Audio APE demuxer
3  * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org>
4  * based upon libdemac from Dave Chapman.
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <stdio.h>
24 
25 #include "libavutil/intreadwrite.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "apetag.h"
29 
30 /* The earliest and latest file formats supported by this library */
31 #define APE_MIN_VERSION 3800
32 #define APE_MAX_VERSION 3990
33 
34 #define MAC_FORMAT_FLAG_8_BIT 1 // is 8-bit [OBSOLETE]
35 #define MAC_FORMAT_FLAG_CRC 2 // uses the new CRC32 error detection [OBSOLETE]
36 #define MAC_FORMAT_FLAG_HAS_PEAK_LEVEL 4 // uint32 nPeakLevel after the header [OBSOLETE]
37 #define MAC_FORMAT_FLAG_24_BIT 8 // is 24-bit [OBSOLETE]
38 #define MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS 16 // has the number of seek elements after the peak level
39 #define MAC_FORMAT_FLAG_CREATE_WAV_HEADER 32 // create the wave header on decompression (not stored)
40 
41 #define MAC_SUBFRAME_SIZE 4608
42 
43 #define APE_EXTRADATA_SIZE 6
44 
45 typedef struct {
46  int64_t pos;
47  int nblocks;
48  int size;
49  int skip;
50  int64_t pts;
51 } APEFrame;
52 
53 typedef struct {
54  /* Derived fields */
55  uint32_t junklength;
56  uint32_t firstframe;
57  uint32_t totalsamples;
60 
61  /* Info from Descriptor Block */
62  char magic[4];
63  int16_t fileversion;
64  int16_t padding1;
65  uint32_t descriptorlength;
66  uint32_t headerlength;
67  uint32_t seektablelength;
68  uint32_t wavheaderlength;
69  uint32_t audiodatalength;
71  uint32_t wavtaillength;
72  uint8_t md5[16];
73 
74  /* Info from Header Block */
75  uint16_t compressiontype;
76  uint16_t formatflags;
77  uint32_t blocksperframe;
78  uint32_t finalframeblocks;
79  uint32_t totalframes;
80  uint16_t bps;
81  uint16_t channels;
82  uint32_t samplerate;
83 
84  /* Seektable */
85  uint32_t *seektable;
87 } APEContext;
88 
89 static int ape_probe(AVProbeData * p)
90 {
91  if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
92  return AVPROBE_SCORE_MAX;
93 
94  return 0;
95 }
96 
97 static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
98 {
99 #ifdef DEBUG
100  int i;
101 
102  av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
103  av_log(s, AV_LOG_DEBUG, "magic = \"%c%c%c%c\"\n", ape_ctx->magic[0], ape_ctx->magic[1], ape_ctx->magic[2], ape_ctx->magic[3]);
104  av_log(s, AV_LOG_DEBUG, "fileversion = %"PRId16"\n", ape_ctx->fileversion);
105  av_log(s, AV_LOG_DEBUG, "descriptorlength = %"PRIu32"\n", ape_ctx->descriptorlength);
106  av_log(s, AV_LOG_DEBUG, "headerlength = %"PRIu32"\n", ape_ctx->headerlength);
107  av_log(s, AV_LOG_DEBUG, "seektablelength = %"PRIu32"\n", ape_ctx->seektablelength);
108  av_log(s, AV_LOG_DEBUG, "wavheaderlength = %"PRIu32"\n", ape_ctx->wavheaderlength);
109  av_log(s, AV_LOG_DEBUG, "audiodatalength = %"PRIu32"\n", ape_ctx->audiodatalength);
110  av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %"PRIu32"\n", ape_ctx->audiodatalength_high);
111  av_log(s, AV_LOG_DEBUG, "wavtaillength = %"PRIu32"\n", ape_ctx->wavtaillength);
112  av_log(s, AV_LOG_DEBUG, "md5 = ");
113  for (i = 0; i < 16; i++)
114  av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
115  av_log(s, AV_LOG_DEBUG, "\n");
116 
117  av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
118 
119  av_log(s, AV_LOG_DEBUG, "compressiontype = %"PRIu16"\n", ape_ctx->compressiontype);
120  av_log(s, AV_LOG_DEBUG, "formatflags = %"PRIu16"\n", ape_ctx->formatflags);
121  av_log(s, AV_LOG_DEBUG, "blocksperframe = %"PRIu32"\n", ape_ctx->blocksperframe);
122  av_log(s, AV_LOG_DEBUG, "finalframeblocks = %"PRIu32"\n", ape_ctx->finalframeblocks);
123  av_log(s, AV_LOG_DEBUG, "totalframes = %"PRIu32"\n", ape_ctx->totalframes);
124  av_log(s, AV_LOG_DEBUG, "bps = %"PRIu16"\n", ape_ctx->bps);
125  av_log(s, AV_LOG_DEBUG, "channels = %"PRIu16"\n", ape_ctx->channels);
126  av_log(s, AV_LOG_DEBUG, "samplerate = %"PRIu32"\n", ape_ctx->samplerate);
127 
128  av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
129  if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
130  av_log(s, AV_LOG_DEBUG, "No seektable\n");
131  } else {
132  for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
133  if (i < ape_ctx->totalframes - 1) {
134  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32" (%"PRIu32" bytes)",
135  i, ape_ctx->seektable[i],
136  ape_ctx->seektable[i + 1] - ape_ctx->seektable[i]);
137  if (ape_ctx->bittable)
138  av_log(s, AV_LOG_DEBUG, " + %2d bits\n",
139  ape_ctx->bittable[i]);
140  av_log(s, AV_LOG_DEBUG, "\n");
141  } else {
142  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32"\n", i, ape_ctx->seektable[i]);
143  }
144  }
145  }
146 
147  av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
148  for (i = 0; i < ape_ctx->totalframes; i++)
149  av_log(s, AV_LOG_DEBUG, "%8d %8"PRId64" %8d (%d samples)\n", i,
150  ape_ctx->frames[i].pos, ape_ctx->frames[i].size,
151  ape_ctx->frames[i].nblocks);
152 
153  av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
154  av_log(s, AV_LOG_DEBUG, "junklength = %"PRIu32"\n", ape_ctx->junklength);
155  av_log(s, AV_LOG_DEBUG, "firstframe = %"PRIu32"\n", ape_ctx->firstframe);
156  av_log(s, AV_LOG_DEBUG, "totalsamples = %"PRIu32"\n", ape_ctx->totalsamples);
157 #endif
158 }
159 
161 {
162  AVIOContext *pb = s->pb;
163  APEContext *ape = s->priv_data;
164  AVStream *st;
165  uint32_t tag;
166  int i;
167  int total_blocks, final_size = 0;
168  int64_t pts, file_size;
169 
170  /* Skip any leading junk such as id3v2 tags */
171  ape->junklength = avio_tell(pb);
172 
173  tag = avio_rl32(pb);
174  if (tag != MKTAG('M', 'A', 'C', ' '))
175  return -1;
176 
177  ape->fileversion = avio_rl16(pb);
178 
180  av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n",
181  ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
182  return -1;
183  }
184 
185  if (ape->fileversion >= 3980) {
186  ape->padding1 = avio_rl16(pb);
187  ape->descriptorlength = avio_rl32(pb);
188  ape->headerlength = avio_rl32(pb);
189  ape->seektablelength = avio_rl32(pb);
190  ape->wavheaderlength = avio_rl32(pb);
191  ape->audiodatalength = avio_rl32(pb);
192  ape->audiodatalength_high = avio_rl32(pb);
193  ape->wavtaillength = avio_rl32(pb);
194  avio_read(pb, ape->md5, 16);
195 
196  /* Skip any unknown bytes at the end of the descriptor.
197  This is for future compatibility */
198  if (ape->descriptorlength > 52)
199  avio_skip(pb, ape->descriptorlength - 52);
200 
201  /* Read header data */
202  ape->compressiontype = avio_rl16(pb);
203  ape->formatflags = avio_rl16(pb);
204  ape->blocksperframe = avio_rl32(pb);
205  ape->finalframeblocks = avio_rl32(pb);
206  ape->totalframes = avio_rl32(pb);
207  ape->bps = avio_rl16(pb);
208  ape->channels = avio_rl16(pb);
209  ape->samplerate = avio_rl32(pb);
210  } else {
211  ape->descriptorlength = 0;
212  ape->headerlength = 32;
213 
214  ape->compressiontype = avio_rl16(pb);
215  ape->formatflags = avio_rl16(pb);
216  ape->channels = avio_rl16(pb);
217  ape->samplerate = avio_rl32(pb);
218  ape->wavheaderlength = avio_rl32(pb);
219  ape->wavtaillength = avio_rl32(pb);
220  ape->totalframes = avio_rl32(pb);
221  ape->finalframeblocks = avio_rl32(pb);
222 
224  avio_skip(pb, 4); /* Skip the peak level */
225  ape->headerlength += 4;
226  }
227 
229  ape->seektablelength = avio_rl32(pb);
230  ape->headerlength += 4;
231  ape->seektablelength *= sizeof(int32_t);
232  } else
233  ape->seektablelength = ape->totalframes * sizeof(int32_t);
234 
236  ape->bps = 8;
237  else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
238  ape->bps = 24;
239  else
240  ape->bps = 16;
241 
242  if (ape->fileversion >= 3950)
243  ape->blocksperframe = 73728 * 4;
244  else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800 && ape->compressiontype >= 4000))
245  ape->blocksperframe = 73728;
246  else
247  ape->blocksperframe = 9216;
248 
249  /* Skip any stored wav header */
251  avio_skip(pb, ape->wavheaderlength);
252  }
253 
254  if(!ape->totalframes){
255  av_log(s, AV_LOG_ERROR, "No frames in the file!\n");
256  return AVERROR(EINVAL);
257  }
258  if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
259  av_log(s, AV_LOG_ERROR, "Too many frames: %"PRIu32"\n",
260  ape->totalframes);
261  return -1;
262  }
263  if (ape->seektablelength / sizeof(*ape->seektable) < ape->totalframes) {
264  av_log(s, AV_LOG_ERROR,
265  "Number of seek entries is less than number of frames: %zu vs. %"PRIu32"\n",
266  ape->seektablelength / sizeof(*ape->seektable), ape->totalframes);
267  return AVERROR_INVALIDDATA;
268  }
269  ape->frames = av_malloc(ape->totalframes * sizeof(APEFrame));
270  if(!ape->frames)
271  return AVERROR(ENOMEM);
272  ape->firstframe = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
273  if (ape->fileversion < 3810)
274  ape->firstframe += ape->totalframes;
275  ape->currentframe = 0;
276 
277 
278  ape->totalsamples = ape->finalframeblocks;
279  if (ape->totalframes > 1)
280  ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
281 
282  if (ape->seektablelength > 0) {
283  ape->seektable = av_malloc(ape->seektablelength);
284  if (!ape->seektable)
285  return AVERROR(ENOMEM);
286  for (i = 0; i < ape->seektablelength / sizeof(uint32_t) && !pb->eof_reached; i++)
287  ape->seektable[i] = avio_rl32(pb);
288  if (ape->fileversion < 3810) {
289  ape->bittable = av_malloc(ape->totalframes);
290  if (!ape->bittable)
291  return AVERROR(ENOMEM);
292  for (i = 0; i < ape->totalframes && !pb->eof_reached; i++)
293  ape->bittable[i] = avio_r8(pb);
294  }
295  }
296 
297  ape->frames[0].pos = ape->firstframe;
298  ape->frames[0].nblocks = ape->blocksperframe;
299  ape->frames[0].skip = 0;
300  for (i = 1; i < ape->totalframes; i++) {
301  ape->frames[i].pos = ape->seektable[i] + ape->junklength;
302  ape->frames[i].nblocks = ape->blocksperframe;
303  ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
304  ape->frames[i].skip = (ape->frames[i].pos - ape->frames[0].pos) & 3;
305  }
306  ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
307  /* calculate final packet size from total file size, if available */
308  file_size = avio_size(pb);
309  if (file_size > 0) {
310  final_size = file_size - ape->frames[ape->totalframes - 1].pos -
311  ape->wavtaillength;
312  final_size -= final_size & 3;
313  }
314  if (file_size <= 0 || final_size <= 0)
315  final_size = ape->finalframeblocks * 8;
316  ape->frames[ape->totalframes - 1].size = final_size;
317 
318  for (i = 0; i < ape->totalframes; i++) {
319  if(ape->frames[i].skip){
320  ape->frames[i].pos -= ape->frames[i].skip;
321  ape->frames[i].size += ape->frames[i].skip;
322  }
323  ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
324  }
325  if (ape->fileversion < 3810) {
326  for (i = 0; i < ape->totalframes; i++) {
327  if (i < ape->totalframes - 1 && ape->bittable[i + 1])
328  ape->frames[i].size += 4;
329  ape->frames[i].skip <<= 3;
330  ape->frames[i].skip += ape->bittable[i];
331  }
332  }
333 
334  ape_dumpinfo(s, ape);
335 
336  av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %"PRIu16"\n",
337  ape->fileversion / 1000, (ape->fileversion % 1000) / 10,
338  ape->compressiontype);
339 
340  /* now we are ready: build format streams */
341  st = avformat_new_stream(s, NULL);
342  if (!st)
343  return -1;
344 
345  total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
346 
349  st->codec->codec_tag = MKTAG('A', 'P', 'E', ' ');
350  st->codec->channels = ape->channels;
351  st->codec->sample_rate = ape->samplerate;
352  st->codec->bits_per_coded_sample = ape->bps;
353 
354  st->nb_frames = ape->totalframes;
355  st->start_time = 0;
356  st->duration = total_blocks / MAC_SUBFRAME_SIZE;
358 
361  AV_WL16(st->codec->extradata + 0, ape->fileversion);
362  AV_WL16(st->codec->extradata + 2, ape->compressiontype);
363  AV_WL16(st->codec->extradata + 4, ape->formatflags);
364 
365  pts = 0;
366  for (i = 0; i < ape->totalframes; i++) {
367  ape->frames[i].pts = pts;
368  av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
369  pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
370  }
371 
372  /* try to read APE tags */
373  if (pb->seekable) {
374  ff_ape_parse_tag(s);
375  avio_seek(pb, 0, SEEK_SET);
376  }
377 
378  return 0;
379 }
380 
382 {
383  int ret;
384  int nblocks;
385  APEContext *ape = s->priv_data;
386  uint32_t extra_size = 8;
387 
388  if (s->pb->eof_reached)
389  return AVERROR_EOF;
390  if (ape->currentframe >= ape->totalframes)
391  return AVERROR_EOF;
392 
393  if (avio_seek(s->pb, ape->frames[ape->currentframe].pos, SEEK_SET) < 0)
394  return AVERROR(EIO);
395 
396  /* Calculate how many blocks there are in this frame */
397  if (ape->currentframe == (ape->totalframes - 1))
398  nblocks = ape->finalframeblocks;
399  else
400  nblocks = ape->blocksperframe;
401 
402  if (ape->frames[ape->currentframe].size <= 0 ||
403  ape->frames[ape->currentframe].size > INT_MAX - extra_size) {
404  av_log(s, AV_LOG_ERROR, "invalid packet size: %d\n",
405  ape->frames[ape->currentframe].size);
406  ape->currentframe++;
407  return AVERROR(EIO);
408  }
409 
410  if (av_new_packet(pkt, ape->frames[ape->currentframe].size + extra_size) < 0)
411  return AVERROR(ENOMEM);
412 
413  AV_WL32(pkt->data , nblocks);
414  AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
415  ret = avio_read(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
416 
417  pkt->pts = ape->frames[ape->currentframe].pts;
418  pkt->stream_index = 0;
419 
420  /* note: we need to modify the packet size here to handle the last
421  packet */
422  pkt->size = ret + extra_size;
423 
424  ape->currentframe++;
425 
426  return 0;
427 }
428 
430 {
431  APEContext *ape = s->priv_data;
432 
433  av_freep(&ape->frames);
434  av_freep(&ape->seektable);
435  av_freep(&ape->bittable);
436  return 0;
437 }
438 
439 static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
440 {
441  AVStream *st = s->streams[stream_index];
442  APEContext *ape = s->priv_data;
443  int index = av_index_search_timestamp(st, timestamp, flags);
444 
445  if (index < 0)
446  return -1;
447 
448  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
449  return -1;
450  ape->currentframe = index;
451  return 0;
452 }
453 
455  .name = "ape",
456  .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
457  .priv_data_size = sizeof(APEContext),
463  .extensions = "ape,apl,mac",
464 };