FFmpeg  4.0
cafdec.c
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1 /*
2  * Core Audio Format demuxer
3  * Copyright (c) 2007 Justin Ruggles
4  * Copyright (c) 2009 Peter Ross
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 /**
24  * @file
25  * Core Audio Format demuxer
26  */
27 
28 #include <inttypes.h>
29 
30 #include "avformat.h"
31 #include "internal.h"
32 #include "isom.h"
33 #include "mov_chan.h"
34 #include "libavutil/intreadwrite.h"
35 #include "libavutil/intfloat.h"
36 #include "libavutil/dict.h"
37 #include "caf.h"
38 
39 typedef struct CafContext {
40  int bytes_per_packet; ///< bytes in a packet, or 0 if variable
41  int frames_per_packet; ///< frames in a packet, or 0 if variable
42  int64_t num_bytes; ///< total number of bytes in stream
43 
44  int64_t packet_cnt; ///< packet counter
45  int64_t frame_cnt; ///< frame counter
46 
47  int64_t data_start; ///< data start position, in bytes
48  int64_t data_size; ///< raw data size, in bytes
49 } CafContext;
50 
51 static int probe(AVProbeData *p)
52 {
53  if (AV_RB32(p->buf) == MKBETAG('c','a','f','f') && AV_RB16(&p->buf[4]) == 1)
54  return AVPROBE_SCORE_MAX;
55  return 0;
56 }
57 
58 /** Read audio description chunk */
60 {
61  AVIOContext *pb = s->pb;
62  CafContext *caf = s->priv_data;
63  AVStream *st;
64  int flags;
65 
66  /* new audio stream */
67  st = avformat_new_stream(s, NULL);
68  if (!st)
69  return AVERROR(ENOMEM);
70 
71  /* parse format description */
74  st->codecpar->codec_tag = avio_rl32(pb);
75  flags = avio_rb32(pb);
76  caf->bytes_per_packet = avio_rb32(pb);
78  caf->frames_per_packet = avio_rb32(pb);
79  st->codecpar->channels = avio_rb32(pb);
81 
82  /* calculate bit rate for constant size packets */
83  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
84  st->codecpar->bit_rate = (uint64_t)st->codecpar->sample_rate * (uint64_t)caf->bytes_per_packet * 8
85  / (uint64_t)caf->frames_per_packet;
86  } else {
87  st->codecpar->bit_rate = 0;
88  }
89 
90  /* determine codec */
91  if (st->codecpar->codec_tag == MKTAG('l','p','c','m'))
93  else
95  return 0;
96 }
97 
98 /** Read magic cookie chunk */
99 static int read_kuki_chunk(AVFormatContext *s, int64_t size)
100 {
101  AVIOContext *pb = s->pb;
102  AVStream *st = s->streams[0];
103 
104  if (size < 0 || size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
105  return -1;
106 
107  if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
108  /* The magic cookie format for AAC is an mp4 esds atom.
109  The lavc AAC decoder requires the data from the codec specific
110  description as extradata input. */
111  int strt, skip;
112 
113  strt = avio_tell(pb);
114  ff_mov_read_esds(s, pb);
115  skip = size - (avio_tell(pb) - strt);
116  if (skip < 0 || !st->codecpar->extradata ||
118  av_log(s, AV_LOG_ERROR, "invalid AAC magic cookie\n");
119  return AVERROR_INVALIDDATA;
120  }
121  avio_skip(pb, skip);
122  } else if (st->codecpar->codec_id == AV_CODEC_ID_ALAC) {
123 #define ALAC_PREAMBLE 12
124 #define ALAC_HEADER 36
125 #define ALAC_NEW_KUKI 24
126  uint8_t preamble[12];
127  if (size < ALAC_NEW_KUKI) {
128  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
129  avio_skip(pb, size);
130  return AVERROR_INVALIDDATA;
131  }
132  if (avio_read(pb, preamble, ALAC_PREAMBLE) != ALAC_PREAMBLE) {
133  av_log(s, AV_LOG_ERROR, "failed to read preamble\n");
134  return AVERROR_INVALIDDATA;
135  }
136 
137  av_freep(&st->codecpar->extradata);
139  return AVERROR(ENOMEM);
140 
141  /* For the old style cookie, we skip 12 bytes, then read 36 bytes.
142  * The new style cookie only contains the last 24 bytes of what was
143  * 36 bytes in the old style cookie, so we fabricate the first 12 bytes
144  * in that case to maintain compatibility. */
145  if (!memcmp(&preamble[4], "frmaalac", 8)) {
146  if (size < ALAC_PREAMBLE + ALAC_HEADER) {
147  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
148  av_freep(&st->codecpar->extradata);
149  return AVERROR_INVALIDDATA;
150  }
151  if (avio_read(pb, st->codecpar->extradata, ALAC_HEADER) != ALAC_HEADER) {
152  av_log(s, AV_LOG_ERROR, "failed to read kuki header\n");
153  av_freep(&st->codecpar->extradata);
154  return AVERROR_INVALIDDATA;
155  }
156  avio_skip(pb, size - ALAC_PREAMBLE - ALAC_HEADER);
157  } else {
158  AV_WB32(st->codecpar->extradata, 36);
159  memcpy(&st->codecpar->extradata[4], "alac", 4);
160  AV_WB32(&st->codecpar->extradata[8], 0);
161  memcpy(&st->codecpar->extradata[12], preamble, 12);
162  if (avio_read(pb, &st->codecpar->extradata[24], ALAC_NEW_KUKI - 12) != ALAC_NEW_KUKI - 12) {
163  av_log(s, AV_LOG_ERROR, "failed to read new kuki header\n");
164  av_freep(&st->codecpar->extradata);
165  return AVERROR_INVALIDDATA;
166  }
167  avio_skip(pb, size - ALAC_NEW_KUKI);
168  }
169  } else if (st->codecpar->codec_id == AV_CODEC_ID_OPUS) {
170  // The data layout for Opus is currently unknown, so we do not export
171  // extradata at all. Multichannel streams are not supported.
172  if (st->codecpar->channels > 2) {
173  avpriv_request_sample(s, "multichannel Opus in CAF");
174  return AVERROR_PATCHWELCOME;
175  }
176  avio_skip(pb, size);
177  } else {
178  av_freep(&st->codecpar->extradata);
179  if (ff_get_extradata(s, st->codecpar, pb, size) < 0)
180  return AVERROR(ENOMEM);
181  }
182 
183  return 0;
184 }
185 
186 /** Read packet table chunk */
187 static int read_pakt_chunk(AVFormatContext *s, int64_t size)
188 {
189  AVIOContext *pb = s->pb;
190  AVStream *st = s->streams[0];
191  CafContext *caf = s->priv_data;
192  int64_t pos = 0, ccount, num_packets;
193  int i;
194 
195  ccount = avio_tell(pb);
196 
197  num_packets = avio_rb64(pb);
198  if (num_packets < 0 || INT32_MAX / sizeof(AVIndexEntry) < num_packets)
199  return AVERROR_INVALIDDATA;
200 
201  st->nb_frames = avio_rb64(pb); /* valid frames */
202  st->nb_frames += avio_rb32(pb); /* priming frames */
203  st->nb_frames += avio_rb32(pb); /* remainder frames */
204 
205  st->duration = 0;
206  for (i = 0; i < num_packets; i++) {
207  av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME);
210  }
211 
212  if (avio_tell(pb) - ccount > size) {
213  av_log(s, AV_LOG_ERROR, "error reading packet table\n");
214  return AVERROR_INVALIDDATA;
215  }
216  avio_skip(pb, ccount + size - avio_tell(pb));
217 
218  caf->num_bytes = pos;
219  return 0;
220 }
221 
222 /** Read information chunk */
223 static void read_info_chunk(AVFormatContext *s, int64_t size)
224 {
225  AVIOContext *pb = s->pb;
226  unsigned int i;
227  unsigned int nb_entries = avio_rb32(pb);
228  for (i = 0; i < nb_entries && !avio_feof(pb); i++) {
229  char key[32];
230  char value[1024];
231  avio_get_str(pb, INT_MAX, key, sizeof(key));
232  avio_get_str(pb, INT_MAX, value, sizeof(value));
233  av_dict_set(&s->metadata, key, value, 0);
234  }
235 }
236 
238 {
239  AVIOContext *pb = s->pb;
240  CafContext *caf = s->priv_data;
241  AVStream *st;
242  uint32_t tag = 0;
243  int found_data, ret;
244  int64_t size, pos;
245 
246  avio_skip(pb, 8); /* magic, version, file flags */
247 
248  /* audio description chunk */
249  if (avio_rb32(pb) != MKBETAG('d','e','s','c')) {
250  av_log(s, AV_LOG_ERROR, "desc chunk not present\n");
251  return AVERROR_INVALIDDATA;
252  }
253  size = avio_rb64(pb);
254  if (size != 32)
255  return AVERROR_INVALIDDATA;
256 
257  ret = read_desc_chunk(s);
258  if (ret)
259  return ret;
260  st = s->streams[0];
261 
262  /* parse each chunk */
263  found_data = 0;
264  while (!avio_feof(pb)) {
265 
266  /* stop at data chunk if seeking is not supported or
267  data chunk size is unknown */
268  if (found_data && (caf->data_size < 0 || !(pb->seekable & AVIO_SEEKABLE_NORMAL)))
269  break;
270 
271  tag = avio_rb32(pb);
272  size = avio_rb64(pb);
273  pos = avio_tell(pb);
274  if (avio_feof(pb))
275  break;
276 
277  switch (tag) {
278  case MKBETAG('d','a','t','a'):
279  avio_skip(pb, 4); /* edit count */
280  caf->data_start = avio_tell(pb);
281  caf->data_size = size < 0 ? -1 : size - 4;
282  if (caf->data_size > 0 && (pb->seekable & AVIO_SEEKABLE_NORMAL))
283  avio_skip(pb, caf->data_size);
284  found_data = 1;
285  break;
286 
287  case MKBETAG('c','h','a','n'):
288  if ((ret = ff_mov_read_chan(s, s->pb, st, size)) < 0)
289  return ret;
290  break;
291 
292  /* magic cookie chunk */
293  case MKBETAG('k','u','k','i'):
294  if (read_kuki_chunk(s, size))
295  return AVERROR_INVALIDDATA;
296  break;
297 
298  /* packet table chunk */
299  case MKBETAG('p','a','k','t'):
300  if (read_pakt_chunk(s, size))
301  return AVERROR_INVALIDDATA;
302  break;
303 
304  case MKBETAG('i','n','f','o'):
305  read_info_chunk(s, size);
306  break;
307 
308  default:
310  "skipping CAF chunk: %08"PRIX32" (%s), size %"PRId64"\n",
311  tag, av_fourcc2str(av_bswap32(tag)), size);
312  case MKBETAG('f','r','e','e'):
313  if (size < 0)
314  return AVERROR_INVALIDDATA;
315  break;
316  }
317 
318  if (size > 0) {
319  if (pos > INT64_MAX - size)
320  return AVERROR_INVALIDDATA;
321  avio_skip(pb, FFMAX(0, pos + size - avio_tell(pb)));
322  }
323  }
324 
325  if (!found_data)
326  return AVERROR_INVALIDDATA;
327 
328  if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) {
329  if (caf->data_size > 0)
330  st->nb_frames = (caf->data_size / caf->bytes_per_packet) * caf->frames_per_packet;
331  } else if (st->nb_index_entries && st->duration > 0) {
332  if (st->codecpar->sample_rate && caf->data_size / st->duration > INT64_MAX / st->codecpar->sample_rate / 8) {
333  av_log(s, AV_LOG_ERROR, "Overflow during bit rate calculation %d * 8 * %"PRId64"\n",
334  st->codecpar->sample_rate, caf->data_size / st->duration);
335  return AVERROR_INVALIDDATA;
336  }
337  st->codecpar->bit_rate = st->codecpar->sample_rate * 8LL *
338  (caf->data_size / st->duration);
339  } else {
340  av_log(s, AV_LOG_ERROR, "Missing packet table. It is required when "
341  "block size or frame size are variable.\n");
342  return AVERROR_INVALIDDATA;
343  }
344 
345  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
346  st->start_time = 0;
347 
348  /* position the stream at the start of data */
349  if (caf->data_size >= 0)
350  avio_seek(pb, caf->data_start, SEEK_SET);
351 
352  return 0;
353 }
354 
355 #define CAF_MAX_PKT_SIZE 4096
356 
358 {
359  AVIOContext *pb = s->pb;
360  AVStream *st = s->streams[0];
361  CafContext *caf = s->priv_data;
362  int res, pkt_size = 0, pkt_frames = 0;
363  int64_t left = CAF_MAX_PKT_SIZE;
364 
365  if (avio_feof(pb))
366  return AVERROR_EOF;
367 
368  /* don't read past end of data chunk */
369  if (caf->data_size > 0) {
370  left = (caf->data_start + caf->data_size) - avio_tell(pb);
371  if (!left)
372  return AVERROR_EOF;
373  if (left < 0)
374  return AVERROR(EIO);
375  }
376 
377  pkt_frames = caf->frames_per_packet;
378  pkt_size = caf->bytes_per_packet;
379 
380  if (pkt_size > 0 && pkt_frames == 1) {
381  pkt_size = (CAF_MAX_PKT_SIZE / pkt_size) * pkt_size;
382  pkt_size = FFMIN(pkt_size, left);
383  pkt_frames = pkt_size / caf->bytes_per_packet;
384  } else if (st->nb_index_entries) {
385  if (caf->packet_cnt < st->nb_index_entries - 1) {
386  pkt_size = st->index_entries[caf->packet_cnt + 1].pos - st->index_entries[caf->packet_cnt].pos;
387  pkt_frames = st->index_entries[caf->packet_cnt + 1].timestamp - st->index_entries[caf->packet_cnt].timestamp;
388  } else if (caf->packet_cnt == st->nb_index_entries - 1) {
389  pkt_size = caf->num_bytes - st->index_entries[caf->packet_cnt].pos;
390  pkt_frames = st->duration - st->index_entries[caf->packet_cnt].timestamp;
391  } else {
392  return AVERROR(EIO);
393  }
394  }
395 
396  if (pkt_size == 0 || pkt_frames == 0 || pkt_size > left)
397  return AVERROR(EIO);
398 
399  res = av_get_packet(pb, pkt, pkt_size);
400  if (res < 0)
401  return res;
402 
403  pkt->size = res;
404  pkt->stream_index = 0;
405  pkt->dts = pkt->pts = caf->frame_cnt;
406 
407  caf->packet_cnt++;
408  caf->frame_cnt += pkt_frames;
409 
410  return 0;
411 }
412 
413 static int read_seek(AVFormatContext *s, int stream_index,
414  int64_t timestamp, int flags)
415 {
416  AVStream *st = s->streams[0];
417  CafContext *caf = s->priv_data;
418  int64_t pos, packet_cnt, frame_cnt;
419 
420  timestamp = FFMAX(timestamp, 0);
421 
422  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
423  /* calculate new byte position based on target frame position */
424  pos = caf->bytes_per_packet * (timestamp / caf->frames_per_packet);
425  if (caf->data_size > 0)
426  pos = FFMIN(pos, caf->data_size);
427  packet_cnt = pos / caf->bytes_per_packet;
428  frame_cnt = caf->frames_per_packet * packet_cnt;
429  } else if (st->nb_index_entries) {
430  packet_cnt = av_index_search_timestamp(st, timestamp, flags);
431  frame_cnt = st->index_entries[packet_cnt].timestamp;
432  pos = st->index_entries[packet_cnt].pos;
433  } else {
434  return -1;
435  }
436 
437  if (avio_seek(s->pb, pos + caf->data_start, SEEK_SET) < 0)
438  return -1;
439 
440  caf->packet_cnt = packet_cnt;
441  caf->frame_cnt = frame_cnt;
442 
443  return 0;
444 }
445 
447  .name = "caf",
448  .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"),
449  .priv_data_size = sizeof(CafContext),
450  .read_probe = probe,
453  .read_seek = read_seek,
454  .codec_tag = (const AVCodecTag* const []){ ff_codec_caf_tags, 0 },
455 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: cafdec.c:357
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:2038
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3108
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int bytes_per_packet
bytes in a packet, or 0 if variable
Definition: cafdec.c:40
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4811
int64_t pos
Definition: avformat.h:803
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int size
Definition: avcodec.h:1431
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1102
CAF common code.
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
const char * key
static AVPacket pkt
#define CAF_MAX_PKT_SIZE
Definition: cafdec.c:355
static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: cafdec.c:413
static int read_header(AVFormatContext *s)
Definition: cafdec.c:237
Format I/O context.
Definition: avformat.h:1342
#define ALAC_PREAMBLE
Public dictionary API.
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static av_always_inline double av_int2double(uint64_t i)
Reinterpret a 64-bit integer as a double.
Definition: intfloat.h:60
uint8_t
static int read_kuki_chunk(AVFormatContext *s, int64_t size)
Read magic cookie chunk.
Definition: cafdec.c:99
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:801
#define AV_RB32
Definition: intreadwrite.h:130
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
static int flags
Definition: log.c:55
uint32_t tag
Definition: movenc.c:1455
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:922
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3913
#define AVINDEX_KEYFRAME
Definition: avformat.h:810
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1580
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2147
int ff_mp4_read_descr_len(AVIOContext *pb)
Definition: isom.c:451
#define AV_RB16
Definition: intreadwrite.h:53
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define AVERROR(e)
Definition: error.h:43
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:804
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define av_fourcc2str(fourcc)
Definition: avutil.h:348
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
int64_t num_bytes
total number of bytes in stream
Definition: cafdec.c:42
#define FFMAX(a, b)
Definition: common.h:94
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
int block_align
Audio only.
Definition: avcodec.h:4001
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3271
#define FFMIN(a, b)
Definition: common.h:96
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int64_t data_start
data start position, in bytes
Definition: cafdec.c:47
int64_t data_size
raw data size, in bytes
Definition: cafdec.c:48
AVInputFormat ff_caf_demuxer
Definition: cafdec.c:446
#define ALAC_NEW_KUKI
int ff_mov_read_chan(AVFormatContext *s, AVIOContext *pb, AVStream *st, int64_t size)
Read &#39;chan&#39; tag from the input stream.
Definition: mov_chan.c:547
int ff_mov_read_esds(AVFormatContext *fc, AVIOContext *pb)
Definition: mov_esds.c:23
Stream structure.
Definition: avformat.h:873
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
#define av_bswap32
Definition: bswap.h:33
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
int nb_index_entries
Definition: avformat.h:1104
double value
Definition: eval.c:98
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
int frames_per_packet
frames in a packet, or 0 if variable
Definition: cafdec.c:41
static void read_info_chunk(AVFormatContext *s, int64_t size)
Read information chunk.
Definition: cafdec.c:223
static enum AVCodecID ff_mov_get_lpcm_codec_id(int bps, int flags)
Compute codec id for &#39;lpcm&#39; tag.
Definition: isom.h:357
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static int read_pakt_chunk(AVFormatContext *s, int64_t size)
Read packet table chunk.
Definition: cafdec.c:187
static int probe(AVProbeData *p)
Definition: cafdec.c:51
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
int sample_rate
Audio only.
Definition: avcodec.h:3994
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:912
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3289
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:924
#define ALAC_HEADER
#define MKBETAG(a, b, c, d)
Definition: common.h:367
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:773
void * priv_data
Format private data.
Definition: avformat.h:1370
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3926
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3898
int channels
Audio only.
Definition: avcodec.h:3990
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1429
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:880
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:358
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3888
static int read_desc_chunk(AVFormatContext *s)
Read audio description chunk.
Definition: cafdec.c:59
int stream_index
Definition: avcodec.h:1432
const AVCodecTag ff_codec_caf_tags[]
Known codec tags for CAF.
Definition: caf.c:34
#define MKTAG(a, b, c, d)
Definition: common.h:366
This structure stores compressed data.
Definition: avcodec.h:1407
int64_t packet_cnt
packet counter
Definition: cafdec.c:44
int64_t frame_cnt
frame counter
Definition: cafdec.c:45
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1423