FFmpeg  4.4
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(const 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 */
73  st->codecpar->sample_rate = av_clipd(av_int2double(avio_rb64(pb)), 0, INT_MAX);
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  if (caf->bytes_per_packet < 0 || caf->frames_per_packet < 0)
83  return AVERROR_INVALIDDATA;
84 
85  /* calculate bit rate for constant size packets */
86  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
87  st->codecpar->bit_rate = (uint64_t)st->codecpar->sample_rate * (uint64_t)caf->bytes_per_packet * 8
88  / (uint64_t)caf->frames_per_packet;
89  } else {
90  st->codecpar->bit_rate = 0;
91  }
92 
93  /* determine codec */
94  if (st->codecpar->codec_tag == MKTAG('l','p','c','m'))
96  else
98  return 0;
99 }
100 
101 /** Read magic cookie chunk */
102 static int read_kuki_chunk(AVFormatContext *s, int64_t size)
103 {
104  AVIOContext *pb = s->pb;
105  AVStream *st = s->streams[0];
106  int ret;
107 
108  if (size < 0 || size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
109  return -1;
110 
111  if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
112  /* The magic cookie format for AAC is an mp4 esds atom.
113  The lavc AAC decoder requires the data from the codec specific
114  description as extradata input. */
115  int strt, skip;
116 
117  strt = avio_tell(pb);
118  ff_mov_read_esds(s, pb);
119  skip = size - (avio_tell(pb) - strt);
120  if (skip < 0 || !st->codecpar->extradata ||
122  av_log(s, AV_LOG_ERROR, "invalid AAC magic cookie\n");
123  return AVERROR_INVALIDDATA;
124  }
125  avio_skip(pb, skip);
126  } else if (st->codecpar->codec_id == AV_CODEC_ID_ALAC) {
127 #define ALAC_PREAMBLE 12
128 #define ALAC_HEADER 36
129 #define ALAC_NEW_KUKI 24
130  uint8_t preamble[12];
131  if (size < ALAC_NEW_KUKI) {
132  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
133  avio_skip(pb, size);
134  return AVERROR_INVALIDDATA;
135  }
136  if (avio_read(pb, preamble, ALAC_PREAMBLE) != ALAC_PREAMBLE) {
137  av_log(s, AV_LOG_ERROR, "failed to read preamble\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  if ((ret = ff_alloc_extradata(st->codecpar, ALAC_HEADER)) < 0)
142  return ret;
143 
144  /* For the old style cookie, we skip 12 bytes, then read 36 bytes.
145  * The new style cookie only contains the last 24 bytes of what was
146  * 36 bytes in the old style cookie, so we fabricate the first 12 bytes
147  * in that case to maintain compatibility. */
148  if (!memcmp(&preamble[4], "frmaalac", 8)) {
149  if (size < ALAC_PREAMBLE + ALAC_HEADER) {
150  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
151  av_freep(&st->codecpar->extradata);
152  return AVERROR_INVALIDDATA;
153  }
154  if (avio_read(pb, st->codecpar->extradata, ALAC_HEADER) != ALAC_HEADER) {
155  av_log(s, AV_LOG_ERROR, "failed to read kuki header\n");
156  av_freep(&st->codecpar->extradata);
157  return AVERROR_INVALIDDATA;
158  }
160  } else {
161  AV_WB32(st->codecpar->extradata, 36);
162  memcpy(&st->codecpar->extradata[4], "alac", 4);
163  AV_WB32(&st->codecpar->extradata[8], 0);
164  memcpy(&st->codecpar->extradata[12], preamble, 12);
165  if (avio_read(pb, &st->codecpar->extradata[24], ALAC_NEW_KUKI - 12) != ALAC_NEW_KUKI - 12) {
166  av_log(s, AV_LOG_ERROR, "failed to read new kuki header\n");
167  av_freep(&st->codecpar->extradata);
168  return AVERROR_INVALIDDATA;
169  }
171  }
172  } else if (st->codecpar->codec_id == AV_CODEC_ID_OPUS) {
173  // The data layout for Opus is currently unknown, so we do not export
174  // extradata at all. Multichannel streams are not supported.
175  if (st->codecpar->channels > 2) {
176  avpriv_request_sample(s, "multichannel Opus in CAF");
177  return AVERROR_PATCHWELCOME;
178  }
179  avio_skip(pb, size);
180  } else if ((ret = ff_get_extradata(s, st->codecpar, pb, size)) < 0) {
181  return ret;
182  }
183 
184  return 0;
185 }
186 
187 /** Read packet table chunk */
188 static int read_pakt_chunk(AVFormatContext *s, int64_t size)
189 {
190  AVIOContext *pb = s->pb;
191  AVStream *st = s->streams[0];
192  CafContext *caf = s->priv_data;
193  int64_t pos = 0, ccount, num_packets;
194  int i;
195  int ret;
196 
197  ccount = avio_tell(pb);
198 
199  num_packets = avio_rb64(pb);
200  if (num_packets < 0 || INT32_MAX / sizeof(AVIndexEntry) < num_packets)
201  return AVERROR_INVALIDDATA;
202 
203  st->nb_frames = avio_rb64(pb); /* valid frames */
204  st->nb_frames += avio_rb32(pb); /* priming frames */
205  st->nb_frames += avio_rb32(pb); /* remainder frames */
206 
207  if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) {
208  st->duration = caf->frames_per_packet * num_packets;
209  pos = caf-> bytes_per_packet * num_packets;
210  } else {
211  st->duration = 0;
212  for (i = 0; i < num_packets; i++) {
213  if (avio_feof(pb))
214  return AVERROR_INVALIDDATA;
215  ret = av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME);
216  if (ret < 0)
217  return ret;
220  }
221  }
222 
223  if (avio_tell(pb) - ccount > size) {
224  av_log(s, AV_LOG_ERROR, "error reading packet table\n");
225  return AVERROR_INVALIDDATA;
226  }
227  avio_skip(pb, ccount + size - avio_tell(pb));
228 
229  caf->num_bytes = pos;
230  return 0;
231 }
232 
233 /** Read information chunk */
234 static void read_info_chunk(AVFormatContext *s, int64_t size)
235 {
236  AVIOContext *pb = s->pb;
237  unsigned int i;
238  unsigned int nb_entries = avio_rb32(pb);
239  for (i = 0; i < nb_entries && !avio_feof(pb); i++) {
240  char key[32];
241  char value[1024];
242  avio_get_str(pb, INT_MAX, key, sizeof(key));
243  avio_get_str(pb, INT_MAX, value, sizeof(value));
244  av_dict_set(&s->metadata, key, value, 0);
245  }
246 }
247 
249 {
250  AVIOContext *pb = s->pb;
251  CafContext *caf = s->priv_data;
252  AVStream *st;
253  uint32_t tag = 0;
254  int found_data, ret;
255  int64_t size, pos;
256 
257  avio_skip(pb, 8); /* magic, version, file flags */
258 
259  /* audio description chunk */
260  if (avio_rb32(pb) != MKBETAG('d','e','s','c')) {
261  av_log(s, AV_LOG_ERROR, "desc chunk not present\n");
262  return AVERROR_INVALIDDATA;
263  }
264  size = avio_rb64(pb);
265  if (size != 32)
266  return AVERROR_INVALIDDATA;
267 
268  ret = read_desc_chunk(s);
269  if (ret)
270  return ret;
271  st = s->streams[0];
272 
273  /* parse each chunk */
274  found_data = 0;
275  while (!avio_feof(pb)) {
276 
277  /* stop at data chunk if seeking is not supported or
278  data chunk size is unknown */
279  if (found_data && (caf->data_size < 0 || !(pb->seekable & AVIO_SEEKABLE_NORMAL)))
280  break;
281 
282  tag = avio_rb32(pb);
283  size = avio_rb64(pb);
284  pos = avio_tell(pb);
285  if (avio_feof(pb))
286  break;
287 
288  switch (tag) {
289  case MKBETAG('d','a','t','a'):
290  avio_skip(pb, 4); /* edit count */
291  caf->data_start = avio_tell(pb);
292  caf->data_size = size < 0 ? -1 : size - 4;
293  if (caf->data_size > 0 && (pb->seekable & AVIO_SEEKABLE_NORMAL))
294  avio_skip(pb, caf->data_size);
295  found_data = 1;
296  break;
297 
298  case MKBETAG('c','h','a','n'):
299  if ((ret = ff_mov_read_chan(s, s->pb, st, size)) < 0)
300  return ret;
301  break;
302 
303  /* magic cookie chunk */
304  case MKBETAG('k','u','k','i'):
305  if (read_kuki_chunk(s, size))
306  return AVERROR_INVALIDDATA;
307  break;
308 
309  /* packet table chunk */
310  case MKBETAG('p','a','k','t'):
311  if (read_pakt_chunk(s, size))
312  return AVERROR_INVALIDDATA;
313  break;
314 
315  case MKBETAG('i','n','f','o'):
317  break;
318 
319  default:
321  "skipping CAF chunk: %08"PRIX32" (%s), size %"PRId64"\n",
323  case MKBETAG('f','r','e','e'):
324  if (size < 0 && found_data)
325  goto found_data;
326  if (size < 0)
327  return AVERROR_INVALIDDATA;
328  break;
329  }
330 
331  if (size > 0) {
332  if (pos > INT64_MAX - size)
333  return AVERROR_INVALIDDATA;
334  avio_skip(pb, FFMAX(0, pos + size - avio_tell(pb)));
335  }
336  }
337 
338  if (!found_data)
339  return AVERROR_INVALIDDATA;
340 
341 found_data:
342  if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) {
343  if (caf->data_size > 0)
344  st->nb_frames = (caf->data_size / caf->bytes_per_packet) * caf->frames_per_packet;
345  } else if (st->nb_index_entries && st->duration > 0) {
346  if (st->codecpar->sample_rate && caf->data_size / st->duration > INT64_MAX / st->codecpar->sample_rate / 8) {
347  av_log(s, AV_LOG_ERROR, "Overflow during bit rate calculation %d * 8 * %"PRId64"\n",
348  st->codecpar->sample_rate, caf->data_size / st->duration);
349  return AVERROR_INVALIDDATA;
350  }
351  st->codecpar->bit_rate = st->codecpar->sample_rate * 8LL *
352  (caf->data_size / st->duration);
353  } else {
354  av_log(s, AV_LOG_ERROR, "Missing packet table. It is required when "
355  "block size or frame size are variable.\n");
356  return AVERROR_INVALIDDATA;
357  }
358 
359  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
360  st->start_time = 0;
361 
362  /* position the stream at the start of data */
363  if (caf->data_size >= 0)
364  avio_seek(pb, caf->data_start, SEEK_SET);
365 
366  return 0;
367 }
368 
369 #define CAF_MAX_PKT_SIZE 4096
370 
372 {
373  AVIOContext *pb = s->pb;
374  AVStream *st = s->streams[0];
375  CafContext *caf = s->priv_data;
376  int res, pkt_size = 0, pkt_frames = 0;
377  int64_t left = CAF_MAX_PKT_SIZE;
378 
379  if (avio_feof(pb))
380  return AVERROR_EOF;
381 
382  /* don't read past end of data chunk */
383  if (caf->data_size > 0) {
384  left = (caf->data_start + caf->data_size) - avio_tell(pb);
385  if (!left)
386  return AVERROR_EOF;
387  if (left < 0)
388  return AVERROR(EIO);
389  }
390 
391  pkt_frames = caf->frames_per_packet;
392  pkt_size = caf->bytes_per_packet;
393 
394  if (pkt_size > 0 && pkt_frames == 1) {
395  pkt_size = (CAF_MAX_PKT_SIZE / pkt_size) * pkt_size;
396  pkt_size = FFMIN(pkt_size, left);
397  pkt_frames = pkt_size / caf->bytes_per_packet;
398  } else if (st->nb_index_entries) {
399  if (caf->packet_cnt < st->nb_index_entries - 1) {
400  pkt_size = st->index_entries[caf->packet_cnt + 1].pos - st->index_entries[caf->packet_cnt].pos;
401  pkt_frames = st->index_entries[caf->packet_cnt + 1].timestamp - st->index_entries[caf->packet_cnt].timestamp;
402  } else if (caf->packet_cnt == st->nb_index_entries - 1) {
403  pkt_size = caf->num_bytes - st->index_entries[caf->packet_cnt].pos;
404  pkt_frames = st->duration - st->index_entries[caf->packet_cnt].timestamp;
405  } else {
406  return AVERROR(EIO);
407  }
408  }
409 
410  if (pkt_size == 0 || pkt_frames == 0 || pkt_size > left)
411  return AVERROR(EIO);
412 
413  res = av_get_packet(pb, pkt, pkt_size);
414  if (res < 0)
415  return res;
416 
417  pkt->size = res;
418  pkt->stream_index = 0;
419  pkt->dts = pkt->pts = caf->frame_cnt;
420 
421  caf->packet_cnt++;
422  caf->frame_cnt += pkt_frames;
423 
424  return 0;
425 }
426 
427 static int read_seek(AVFormatContext *s, int stream_index,
428  int64_t timestamp, int flags)
429 {
430  AVStream *st = s->streams[0];
431  CafContext *caf = s->priv_data;
432  int64_t pos, packet_cnt, frame_cnt;
433 
434  timestamp = FFMAX(timestamp, 0);
435 
436  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
437  /* calculate new byte position based on target frame position */
438  pos = caf->bytes_per_packet * (timestamp / caf->frames_per_packet);
439  if (caf->data_size > 0)
440  pos = FFMIN(pos, caf->data_size);
441  packet_cnt = pos / caf->bytes_per_packet;
442  frame_cnt = caf->frames_per_packet * packet_cnt;
443  } else if (st->nb_index_entries) {
444  packet_cnt = av_index_search_timestamp(st, timestamp, flags);
445  frame_cnt = st->index_entries[packet_cnt].timestamp;
446  pos = st->index_entries[packet_cnt].pos;
447  } else {
448  return -1;
449  }
450 
451  if (avio_seek(s->pb, pos + caf->data_start, SEEK_SET) < 0)
452  return -1;
453 
454  caf->packet_cnt = packet_cnt;
455  caf->frame_cnt = frame_cnt;
456 
457  return 0;
458 }
459 
461  .name = "caf",
462  .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"),
463  .priv_data_size = sizeof(CafContext),
464  .read_probe = probe,
467  .read_seek = read_seek,
468  .codec_tag = ff_caf_codec_tags_list,
469 };
uint8_t
Main libavformat public API header.
#define AVINDEX_KEYFRAME
Definition: avformat.h:811
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:902
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:860
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
#define AV_RB32
Definition: intreadwrite.h:130
#define AV_RB16
Definition: intreadwrite.h:53
#define av_bswap32
Definition: bswap.h:33
const AVCodecTag *const ff_caf_codec_tags_list[]
Definition: caf.c:81
const AVCodecTag ff_codec_caf_tags[]
Known codec tags for CAF.
Definition: caf.c:34
CAF common code.
static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: cafdec.c:427
AVInputFormat ff_caf_demuxer
Definition: cafdec.c:460
static int read_kuki_chunk(AVFormatContext *s, int64_t size)
Read magic cookie chunk.
Definition: cafdec.c:102
#define CAF_MAX_PKT_SIZE
Definition: cafdec.c:369
static void read_info_chunk(AVFormatContext *s, int64_t size)
Read information chunk.
Definition: cafdec.c:234
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: cafdec.c:371
#define ALAC_PREAMBLE
#define ALAC_HEADER
#define ALAC_NEW_KUKI
static int read_header(AVFormatContext *s)
Definition: cafdec.c:248
static int read_desc_chunk(AVFormatContext *s)
Read audio description chunk.
Definition: cafdec.c:59
static int read_pakt_chunk(AVFormatContext *s, int64_t size)
Read packet table chunk.
Definition: cafdec.c:188
static int probe(const AVProbeData *p)
Definition: cafdec.c:51
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define FFMIN(a, b)
Definition: common.h:105
#define MKTAG(a, b, c, d)
Definition: common.h:478
#define MKBETAG(a, b, c, d)
Definition: common.h:479
#define av_clipd
Definition: common.h:173
#define FFMAX(a, b)
Definition: common.h:103
#define NULL
Definition: coverity.c:32
Public dictionary API.
double value
Definition: eval.c:98
@ AV_CODEC_ID_ALAC
Definition: codec_id.h:440
@ AV_CODEC_ID_AAC
Definition: codec_id.h:426
@ AV_CODEC_ID_OPUS
Definition: codec_id.h:484
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding.
Definition: avcodec.h:215
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4505
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:2011
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2128
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
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
#define av_fourcc2str(fourcc)
Definition: avutil.h:348
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
const char * key
int i
Definition: input.c:407
static av_always_inline double av_int2double(uint64_t i)
Reinterpret a 64-bit integer as a double.
Definition: intfloat.h:60
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
int ff_mp4_read_descr_len(AVIOContext *pb)
Definition: isom.c:282
int ff_mov_read_esds(AVFormatContext *fc, AVIOContext *pb)
Definition: mov_esds.c:23
static enum AVCodecID ff_mov_get_lpcm_codec_id(int bps, int flags)
Compute codec id for 'lpcm' tag.
Definition: isom.h:379
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:4941
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:3312
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:3330
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3129
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
int ff_mov_read_chan(AVFormatContext *s, AVIOContext *pb, AVStream *st, int64_t size)
Read 'chan' tag from the input stream.
Definition: mov_chan.c:547
uint32_t tag
Definition: movenc.c:1600
unsigned int pos
Definition: spdifenc.c:412
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
int channels
Audio only.
Definition: codec_par.h:166
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
int64_t pos
Definition: avformat.h:804
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:805
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int size
Definition: packet.h:370
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:368
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:924
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
int nb_index_entries
Definition: avformat.h:1092
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1090
int bytes_per_packet
bytes in a packet, or 0 if variable
Definition: cafdec.c:40
int64_t data_start
data start position, in bytes
Definition: cafdec.c:47
int64_t num_bytes
total number of bytes in stream
Definition: cafdec.c:42
int64_t packet_cnt
packet counter
Definition: cafdec.c:44
int frames_per_packet
frames in a packet, or 0 if variable
Definition: cafdec.c:41
int64_t data_size
raw data size, in bytes
Definition: cafdec.c:48
int64_t frame_cnt
frame counter
Definition: cafdec.c:45
#define avpriv_request_sample(...)
#define av_freep(p)
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59
int size