FFmpeg: libavformat/ape.c Source File

FFmpeg
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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 APE_EXTRADATA_SIZE 6
42 
43  typedef struct {
44   int64_t pos;
45   int nblocks;
46   int size;
47   int skip;
48   int64_t pts;
49 } APEFrame;
50 
51 typedef struct {
52  /* Derived fields */
53   uint32_t junklength;
54   uint32_t firstframe;
55   uint32_t totalsamples;
56   int currentframe;
57   APEFrame *frames;
58 
59  /* Info from Descriptor Block */
60   char magic[4];
61   int16_t fileversion;
62   int16_t padding1;
63   uint32_t descriptorlength;
64   uint32_t headerlength;
65   uint32_t seektablelength;
66   uint32_t wavheaderlength;
67   uint32_t audiodatalength;
68   uint32_t audiodatalength_high;
69   uint32_t wavtaillength;
70   uint8_t md5[16];
71 
72  /* Info from Header Block */
73   uint16_t compressiontype;
74   uint16_t formatflags;
75   uint32_t blocksperframe;
76   uint32_t finalframeblocks;
77   uint32_t totalframes;
78   uint16_t bps;
79   uint16_t channels;
80   uint32_t samplerate;
81 
82  /* Seektable */
83   uint32_t *seektable;
84   uint8_t *bittable;
85 } APEContext;
86 
87  static int ape_probe(AVProbeData * p)
88 {
89  if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
90  return AVPROBE_SCORE_MAX;
91 
92  return 0;
93 }
94 
95  static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
96 {
97 #ifdef DEBUG
98  int i;
99 
100  av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
101  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]);
102  av_log(s, AV_LOG_DEBUG, "fileversion = %"PRId16"\n", ape_ctx->fileversion);
103  av_log(s, AV_LOG_DEBUG, "descriptorlength = %"PRIu32"\n", ape_ctx->descriptorlength);
104  av_log(s, AV_LOG_DEBUG, "headerlength = %"PRIu32"\n", ape_ctx->headerlength);
105  av_log(s, AV_LOG_DEBUG, "seektablelength = %"PRIu32"\n", ape_ctx->seektablelength);
106  av_log(s, AV_LOG_DEBUG, "wavheaderlength = %"PRIu32"\n", ape_ctx->wavheaderlength);
107  av_log(s, AV_LOG_DEBUG, "audiodatalength = %"PRIu32"\n", ape_ctx->audiodatalength);
108  av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %"PRIu32"\n", ape_ctx->audiodatalength_high);
109  av_log(s, AV_LOG_DEBUG, "wavtaillength = %"PRIu32"\n", ape_ctx->wavtaillength);
110  av_log(s, AV_LOG_DEBUG, "md5 = ");
111  for (i = 0; i < 16; i++)
112  av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
113  av_log(s, AV_LOG_DEBUG, "\n");
114 
115  av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
116 
117  av_log(s, AV_LOG_DEBUG, "compressiontype = %"PRIu16"\n", ape_ctx->compressiontype);
118  av_log(s, AV_LOG_DEBUG, "formatflags = %"PRIu16"\n", ape_ctx->formatflags);
119  av_log(s, AV_LOG_DEBUG, "blocksperframe = %"PRIu32"\n", ape_ctx->blocksperframe);
120  av_log(s, AV_LOG_DEBUG, "finalframeblocks = %"PRIu32"\n", ape_ctx->finalframeblocks);
121  av_log(s, AV_LOG_DEBUG, "totalframes = %"PRIu32"\n", ape_ctx->totalframes);
122  av_log(s, AV_LOG_DEBUG, "bps = %"PRIu16"\n", ape_ctx->bps);
123  av_log(s, AV_LOG_DEBUG, "channels = %"PRIu16"\n", ape_ctx->channels);
124  av_log(s, AV_LOG_DEBUG, "samplerate = %"PRIu32"\n", ape_ctx->samplerate);
125 
126  av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
127  if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
128  av_log(s, AV_LOG_DEBUG, "No seektable\n");
129  } else {
130  for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
131  if (i < ape_ctx->totalframes - 1) {
132  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32" (%"PRIu32" bytes)",
133  i, ape_ctx->seektable[i],
134  ape_ctx->seektable[i + 1] - ape_ctx->seektable[i]);
135  if (ape_ctx->bittable)
136  av_log(s, AV_LOG_DEBUG, " + %2d bits\n",
137  ape_ctx->bittable[i]);
138  av_log(s, AV_LOG_DEBUG, "\n");
139  } else {
140  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32"\n", i, ape_ctx->seektable[i]);
141  }
142  }
143  }
144 
145  av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
146  for (i = 0; i < ape_ctx->totalframes; i++)
147  av_log(s, AV_LOG_DEBUG, "%8d %8"PRId64" %8d (%d samples)\n", i,
148  ape_ctx->frames[i].pos, ape_ctx->frames[i].size,
149  ape_ctx->frames[i].nblocks);
150 
151  av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
152  av_log(s, AV_LOG_DEBUG, "junklength = %"PRIu32"\n", ape_ctx->junklength);
153  av_log(s, AV_LOG_DEBUG, "firstframe = %"PRIu32"\n", ape_ctx->firstframe);
154  av_log(s, AV_LOG_DEBUG, "totalsamples = %"PRIu32"\n", ape_ctx->totalsamples);
155 #endif
156 }
157 
158  static int ape_read_header(AVFormatContext * s)
159 {
160  AVIOContext *pb = s->pb;
161  APEContext *ape = s->priv_data;
162  AVStream *st;
163  uint32_t tag;
164  int i;
165  int total_blocks, final_size = 0;
166  int64_t pts, file_size;
167 
168  /* Skip any leading junk such as id3v2 tags */
169  ape->junklength = avio_tell(pb);
170 
171  tag = avio_rl32(pb);
172  if (tag != MKTAG('M', 'A', 'C', ' '))
173  return AVERROR_INVALIDDATA;
174 
175  ape->fileversion = avio_rl16(pb);
176 
177  if (ape->fileversion < APE_MIN_VERSION || ape->fileversion > APE_MAX_VERSION) {
178  av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n",
179  ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
180  return AVERROR_PATCHWELCOME;
181  }
182 
183  if (ape->fileversion >= 3980) {
184  ape->padding1 = avio_rl16(pb);
185  ape->descriptorlength = avio_rl32(pb);
186  ape->headerlength = avio_rl32(pb);
187  ape->seektablelength = avio_rl32(pb);
188  ape->wavheaderlength = avio_rl32(pb);
189  ape->audiodatalength = avio_rl32(pb);
190  ape->audiodatalength_high = avio_rl32(pb);
191  ape->wavtaillength = avio_rl32(pb);
192  avio_read(pb, ape->md5, 16);
193 
194  /* Skip any unknown bytes at the end of the descriptor.
195  This is for future compatibility */
196  if (ape->descriptorlength > 52)
197  avio_skip(pb, ape->descriptorlength - 52);
198 
199  /* Read header data */
200  ape->compressiontype = avio_rl16(pb);
201  ape->formatflags = avio_rl16(pb);
202  ape->blocksperframe = avio_rl32(pb);
203  ape->finalframeblocks = avio_rl32(pb);
204  ape->totalframes = avio_rl32(pb);
205  ape->bps = avio_rl16(pb);
206  ape->channels = avio_rl16(pb);
207  ape->samplerate = avio_rl32(pb);
208  } else {
209  ape->descriptorlength = 0;
210  ape->headerlength = 32;
211 
212  ape->compressiontype = avio_rl16(pb);
213  ape->formatflags = avio_rl16(pb);
214  ape->channels = avio_rl16(pb);
215  ape->samplerate = avio_rl32(pb);
216  ape->wavheaderlength = avio_rl32(pb);
217  ape->wavtaillength = avio_rl32(pb);
218  ape->totalframes = avio_rl32(pb);
219  ape->finalframeblocks = avio_rl32(pb);
220 
221  if (ape->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL) {
222  avio_skip(pb, 4); /* Skip the peak level */
223  ape->headerlength += 4;
224  }
225 
226  if (ape->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS) {
227  ape->seektablelength = avio_rl32(pb);
228  ape->headerlength += 4;
229  ape->seektablelength *= sizeof(int32_t);
230  } else
231  ape->seektablelength = ape->totalframes * sizeof(int32_t);
232 
233  if (ape->formatflags & MAC_FORMAT_FLAG_8_BIT)
234  ape->bps = 8;
235  else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
236  ape->bps = 24;
237  else
238  ape->bps = 16;
239 
240  if (ape->fileversion >= 3950)
241  ape->blocksperframe = 73728 * 4;
242  else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800 && ape->compressiontype >= 4000))
243  ape->blocksperframe = 73728;
244  else
245  ape->blocksperframe = 9216;
246 
247  /* Skip any stored wav header */
248  if (!(ape->formatflags & MAC_FORMAT_FLAG_CREATE_WAV_HEADER))
249  avio_skip(pb, ape->wavheaderlength);
250  }
251 
252  if(!ape->totalframes){
253  av_log(s, AV_LOG_ERROR, "No frames in the file!\n");
254  return AVERROR(EINVAL);
255  }
256  if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
257  av_log(s, AV_LOG_ERROR, "Too many frames: %"PRIu32"\n",
258  ape->totalframes);
259  return AVERROR_INVALIDDATA;
260  }
261  if (ape->seektablelength / sizeof(*ape->seektable) < ape->totalframes) {
262  av_log(s, AV_LOG_ERROR,
263  "Number of seek entries is less than number of frames: %zu vs. %"PRIu32"\n",
264  ape->seektablelength / sizeof(*ape->seektable), ape->totalframes);
265  return AVERROR_INVALIDDATA;
266  }
267  ape->frames = av_malloc(ape->totalframes * sizeof(APEFrame));
268  if(!ape->frames)
269  return AVERROR(ENOMEM);
270  ape->firstframe = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
271  if (ape->fileversion < 3810)
272  ape->firstframe += ape->totalframes;
273  ape->currentframe = 0;
274 
275 
276  ape->totalsamples = ape->finalframeblocks;
277  if (ape->totalframes > 1)
278  ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
279 
280  if (ape->seektablelength > 0) {
281  ape->seektable = av_malloc(ape->seektablelength);
282  if (!ape->seektable)
283  return AVERROR(ENOMEM);
284  for (i = 0; i < ape->seektablelength / sizeof(uint32_t) && !pb->eof_reached; i++)
285  ape->seektable[i] = avio_rl32(pb);
286  if (ape->fileversion < 3810) {
287  ape->bittable = av_malloc(ape->totalframes);
288  if (!ape->bittable)
289  return AVERROR(ENOMEM);
290  for (i = 0; i < ape->totalframes && !pb->eof_reached; i++)
291  ape->bittable[i] = avio_r8(pb);
292  }
293  }
294 
295  ape->frames[0].pos = ape->firstframe;
296  ape->frames[0].nblocks = ape->blocksperframe;
297  ape->frames[0].skip = 0;
298  for (i = 1; i < ape->totalframes; i++) {
299  ape->frames[i].pos = ape->seektable[i] + ape->junklength;
300  ape->frames[i].nblocks = ape->blocksperframe;
301  ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
302  ape->frames[i].skip = (ape->frames[i].pos - ape->frames[0].pos) & 3;
303  }
304  ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
305  /* calculate final packet size from total file size, if available */
306  file_size = avio_size(pb);
307  if (file_size > 0) {
308  final_size = file_size - ape->frames[ape->totalframes - 1].pos -
309  ape->wavtaillength;
310  final_size -= final_size & 3;
311  }
312  if (file_size <= 0 || final_size <= 0)
313  final_size = ape->finalframeblocks * 8;
314  ape->frames[ape->totalframes - 1].size = final_size;
315 
316  for (i = 0; i < ape->totalframes; i++) {
317  if(ape->frames[i].skip){
318  ape->frames[i].pos -= ape->frames[i].skip;
319  ape->frames[i].size += ape->frames[i].skip;
320  }
321  ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
322  }
323  if (ape->fileversion < 3810) {
324  for (i = 0; i < ape->totalframes; i++) {
325  if (i < ape->totalframes - 1 && ape->bittable[i + 1])
326  ape->frames[i].size += 4;
327  ape->frames[i].skip <<= 3;
328  ape->frames[i].skip += ape->bittable[i];
329  }
330  }
331 
332  ape_dumpinfo(s, ape);
333 
334  av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %"PRIu16"\n",
335  ape->fileversion / 1000, (ape->fileversion % 1000) / 10,
336  ape->compressiontype);
337 
338  /* now we are ready: build format streams */
339  st = avformat_new_stream(s, NULL);
340  if (!st)
341  return AVERROR(ENOMEM);
342 
343  total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
344 
345  st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
346  st->codec->codec_id = AV_CODEC_ID_APE;
347  st->codec->codec_tag = MKTAG('A', 'P', 'E', ' ');
348  st->codec->channels = ape->channels;
349  st->codec->sample_rate = ape->samplerate;
350  st->codec->bits_per_coded_sample = ape->bps;
351 
352  st->nb_frames = ape->totalframes;
353  st->start_time = 0;
354  st->duration = total_blocks;
355  avpriv_set_pts_info(st, 64, 1, ape->samplerate);
356 
357  if (ff_alloc_extradata(st->codec, APE_EXTRADATA_SIZE))
358  return AVERROR(ENOMEM);
359  AV_WL16(st->codec->extradata + 0, ape->fileversion);
360  AV_WL16(st->codec->extradata + 2, ape->compressiontype);
361  AV_WL16(st->codec->extradata + 4, ape->formatflags);
362 
363  pts = 0;
364  for (i = 0; i < ape->totalframes; i++) {
365  ape->frames[i].pts = pts;
366  av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
367  pts += ape->blocksperframe;
368  }
369 
370  /* try to read APE tags */
371  if (pb->seekable) {
372  ff_ape_parse_tag(s);
373  avio_seek(pb, 0, SEEK_SET);
374  }
375 
376  return 0;
377 }
378 
379  static int ape_read_packet(AVFormatContext * s, AVPacket * pkt)
380 {
381  int ret;
382  int nblocks;
383  APEContext *ape = s->priv_data;
384  uint32_t extra_size = 8;
385 
386  if (url_feof(s->pb))
387  return AVERROR_EOF;
388  if (ape->currentframe >= ape->totalframes)
389  return AVERROR_EOF;
390 
391  if (avio_seek(s->pb, ape->frames[ape->currentframe].pos, SEEK_SET) < 0)
392  return AVERROR(EIO);
393 
394  /* Calculate how many blocks there are in this frame */
395  if (ape->currentframe == (ape->totalframes - 1))
396  nblocks = ape->finalframeblocks;
397  else
398  nblocks = ape->blocksperframe;
399 
400  if (ape->frames[ape->currentframe].size <= 0 ||
401  ape->frames[ape->currentframe].size > INT_MAX - extra_size) {
402  av_log(s, AV_LOG_ERROR, "invalid packet size: %d\n",
403  ape->frames[ape->currentframe].size);
404  ape->currentframe++;
405  return AVERROR(EIO);
406  }
407 
408  if (av_new_packet(pkt, ape->frames[ape->currentframe].size + extra_size) < 0)
409  return AVERROR(ENOMEM);
410 
411  AV_WL32(pkt->data , nblocks);
412  AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
413  ret = avio_read(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
414  if (ret < 0) {
415  av_free_packet(pkt);
416  return ret;
417  }
418 
419  pkt->pts = ape->frames[ape->currentframe].pts;
420  pkt->stream_index = 0;
421 
422  /* note: we need to modify the packet size here to handle the last
423  packet */
424  pkt->size = ret + extra_size;
425 
426  ape->currentframe++;
427 
428  return 0;
429 }
430 
431  static int ape_read_close(AVFormatContext * s)
432 {
433  APEContext *ape = s->priv_data;
434 
435  av_freep(&ape->frames);
436  av_freep(&ape->seektable);
437  av_freep(&ape->bittable);
438  return 0;
439 }
440 
441  static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
442 {
443  AVStream *st = s->streams[stream_index];
444  APEContext *ape = s->priv_data;
445  int index = av_index_search_timestamp(st, timestamp, flags);
446 
447  if (index < 0)
448  return -1;
449 
450  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
451  return -1;
452  ape->currentframe = index;
453  return 0;
454 }
455 
456  AVInputFormat ff_ape_demuxer = {
457  .name = "ape",
458  .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
459  .priv_data_size = sizeof(APEContext),
460  .read_probe = ape_probe,
461  .read_header = ape_read_header,
462  .read_packet = ape_read_packet,
463  .read_close = ape_read_close,
464  .read_seek = ape_read_seek,
465  .extensions = "ape,apl,mac",
466 };
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