FFmpeg
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 "demux.h"
32 #include "internal.h"
33 #include "isom.h"
34 #include "mov_chan.h"
35 #include "libavcodec/flac.h"
36 #include "libavutil/intreadwrite.h"
37 #include "libavutil/intfloat.h"
38 #include "libavutil/dict.h"
39 #include "caf.h"
40 
41 typedef struct CafContext {
42  int bytes_per_packet; ///< bytes in a packet, or 0 if variable
43  int frames_per_packet; ///< frames in a packet, or 0 if variable
44  int64_t num_bytes; ///< total number of bytes in stream
45 
46  int64_t packet_cnt; ///< packet counter
47  int64_t frame_cnt; ///< frame counter
48 
49  int64_t data_start; ///< data start position, in bytes
50  int64_t data_size; ///< raw data size, in bytes
51 } CafContext;
52 
53 static int probe(const AVProbeData *p)
54 {
55  if (AV_RB32(p->buf) != MKBETAG('c','a','f','f'))
56  return 0;
57  if (AV_RB16(&p->buf[4]) != 1)
58  return 0;
59  if (AV_RB32(p->buf + 8) != MKBETAG('d','e','s','c'))
60  return 0;
61  if (AV_RB64(p->buf + 12) != 32)
62  return 0;
63  return AVPROBE_SCORE_MAX;
64 }
65 
66 /** Read audio description chunk */
68 {
69  AVIOContext *pb = s->pb;
70  CafContext *caf = s->priv_data;
71  AVStream *st;
72  int flags;
73 
74  /* new audio stream */
75  st = avformat_new_stream(s, NULL);
76  if (!st)
77  return AVERROR(ENOMEM);
78 
79  /* parse format description */
81  st->codecpar->sample_rate = av_clipd(av_int2double(avio_rb64(pb)), 0, INT_MAX);
82  st->codecpar->codec_tag = avio_rl32(pb);
83  flags = avio_rb32(pb);
84  caf->bytes_per_packet = avio_rb32(pb);
86  caf->frames_per_packet = avio_rb32(pb);
89 
90  if (caf->bytes_per_packet < 0 || caf->frames_per_packet < 0 || st->codecpar->ch_layout.nb_channels < 0)
91  return AVERROR_INVALIDDATA;
92 
93  /* calculate bit rate for constant size packets */
94  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
95  st->codecpar->bit_rate = (uint64_t)st->codecpar->sample_rate * (uint64_t)caf->bytes_per_packet * 8
96  / (uint64_t)caf->frames_per_packet;
97  } else {
98  st->codecpar->bit_rate = 0;
99  }
100 
101  /* determine codec */
102  if (st->codecpar->codec_tag == MKTAG('l','p','c','m'))
104  else
106  return 0;
107 }
108 
109 /** Read magic cookie chunk */
110 static int read_kuki_chunk(AVFormatContext *s, int64_t size)
111 {
112  AVIOContext *pb = s->pb;
113  AVStream *st = s->streams[0];
114  int ret;
115 
116  if (size < 0 || size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
117  return -1;
118 
119  if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
120  /* The magic cookie format for AAC is an mp4 esds atom.
121  The lavc AAC decoder requires the data from the codec specific
122  description as extradata input. */
123  int strt, skip;
124 
125  strt = avio_tell(pb);
126  ff_mov_read_esds(s, pb);
127  skip = size - (avio_tell(pb) - strt);
128  if (skip < 0 || !st->codecpar->extradata ||
130  av_log(s, AV_LOG_ERROR, "invalid AAC magic cookie\n");
131  return AVERROR_INVALIDDATA;
132  }
133  avio_skip(pb, skip);
134  } else if (st->codecpar->codec_id == AV_CODEC_ID_ALAC) {
135 #define ALAC_PREAMBLE 12
136 #define ALAC_HEADER 36
137 #define ALAC_NEW_KUKI 24
138  uint8_t preamble[12];
139  if (size < ALAC_NEW_KUKI) {
140  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
141  avio_skip(pb, size);
142  return AVERROR_INVALIDDATA;
143  }
144  if (avio_read(pb, preamble, ALAC_PREAMBLE) != ALAC_PREAMBLE) {
145  av_log(s, AV_LOG_ERROR, "failed to read preamble\n");
146  return AVERROR_INVALIDDATA;
147  }
148 
149  if ((ret = ff_alloc_extradata(st->codecpar, ALAC_HEADER)) < 0)
150  return ret;
151 
152  /* For the old style cookie, we skip 12 bytes, then read 36 bytes.
153  * The new style cookie only contains the last 24 bytes of what was
154  * 36 bytes in the old style cookie, so we fabricate the first 12 bytes
155  * in that case to maintain compatibility. */
156  if (!memcmp(&preamble[4], "frmaalac", 8)) {
157  if (size < ALAC_PREAMBLE + ALAC_HEADER) {
158  av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n");
159  av_freep(&st->codecpar->extradata);
160  return AVERROR_INVALIDDATA;
161  }
162  if (avio_read(pb, st->codecpar->extradata, ALAC_HEADER) != ALAC_HEADER) {
163  av_log(s, AV_LOG_ERROR, "failed to read kuki header\n");
164  av_freep(&st->codecpar->extradata);
165  return AVERROR_INVALIDDATA;
166  }
168  } else {
169  AV_WB32(st->codecpar->extradata, 36);
170  memcpy(&st->codecpar->extradata[4], "alac", 4);
171  AV_WB32(&st->codecpar->extradata[8], 0);
172  memcpy(&st->codecpar->extradata[12], preamble, 12);
173  if (avio_read(pb, &st->codecpar->extradata[24], ALAC_NEW_KUKI - 12) != ALAC_NEW_KUKI - 12) {
174  av_log(s, AV_LOG_ERROR, "failed to read new kuki header\n");
175  av_freep(&st->codecpar->extradata);
176  return AVERROR_INVALIDDATA;
177  }
179  }
180  } else if (st->codecpar->codec_id == AV_CODEC_ID_FLAC) {
181  int last, type, flac_metadata_size;
182  uint8_t buf[4];
183  /* The magic cookie format for FLAC consists mostly of an mp4 dfLa atom. */
184  if (size < (16 + FLAC_STREAMINFO_SIZE)) {
185  av_log(s, AV_LOG_ERROR, "invalid FLAC magic cookie\n");
186  return AVERROR_INVALIDDATA;
187  }
188  /* Check cookie version. */
189  if (avio_r8(pb) != 0) {
190  av_log(s, AV_LOG_ERROR, "unknown FLAC magic cookie\n");
191  return AVERROR_INVALIDDATA;
192  }
193  avio_rb24(pb); /* Flags */
194  /* read dfLa fourcc */
195  if (avio_read(pb, buf, 4) != 4) {
196  av_log(s, AV_LOG_ERROR, "failed to read FLAC magic cookie\n");
197  return pb->error < 0 ? pb->error : AVERROR_INVALIDDATA;
198  }
199  if (memcmp(buf, "dfLa", 4)) {
200  av_log(s, AV_LOG_ERROR, "invalid FLAC magic cookie\n");
201  return AVERROR_INVALIDDATA;
202  }
203  /* Check dfLa version. */
204  if (avio_r8(pb) != 0) {
205  av_log(s, AV_LOG_ERROR, "unknown dfLa version\n");
206  return AVERROR_INVALIDDATA;
207  }
208  avio_rb24(pb); /* Flags */
209  if (avio_read(pb, buf, sizeof(buf)) != sizeof(buf)) {
210  av_log(s, AV_LOG_ERROR, "failed to read FLAC metadata block header\n");
211  return pb->error < 0 ? pb->error : AVERROR_INVALIDDATA;
212  }
213  flac_parse_block_header(buf, &last, &type, &flac_metadata_size);
214  if (type != FLAC_METADATA_TYPE_STREAMINFO || flac_metadata_size != FLAC_STREAMINFO_SIZE) {
215  av_log(s, AV_LOG_ERROR, "STREAMINFO must be first FLACMetadataBlock\n");
216  return AVERROR_INVALIDDATA;
217  }
219  if (ret < 0)
220  return ret;
221  if (!last)
222  av_log(s, AV_LOG_WARNING, "non-STREAMINFO FLACMetadataBlock(s) ignored\n");
223  } else if (st->codecpar->codec_id == AV_CODEC_ID_OPUS) {
224  // The data layout for Opus is currently unknown, so we do not export
225  // extradata at all. Multichannel streams are not supported.
226  if (st->codecpar->ch_layout.nb_channels > 2) {
227  avpriv_request_sample(s, "multichannel Opus in CAF");
228  return AVERROR_PATCHWELCOME;
229  }
230  avio_skip(pb, size);
231  } else if ((ret = ff_get_extradata(s, st->codecpar, pb, size)) < 0) {
232  return ret;
233  }
234 
235  return 0;
236 }
237 
238 /** Read packet table chunk */
239 static int read_pakt_chunk(AVFormatContext *s, int64_t size)
240 {
241  AVIOContext *pb = s->pb;
242  AVStream *st = s->streams[0];
243  CafContext *caf = s->priv_data;
244  int64_t pos = 0, ccount, num_packets;
245  int i;
246  int ret;
247 
248  ccount = avio_tell(pb);
249 
250  num_packets = avio_rb64(pb);
251  if (num_packets < 0 || INT32_MAX / sizeof(AVIndexEntry) < num_packets)
252  return AVERROR_INVALIDDATA;
253 
254  st->nb_frames = avio_rb64(pb); /* valid frames */
255  st->nb_frames += avio_rb32(pb); /* priming frames */
256  st->nb_frames += avio_rb32(pb); /* remainder frames */
257 
258  if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) {
259  st->duration = caf->frames_per_packet * num_packets;
260  pos = caf-> bytes_per_packet * num_packets;
261  } else {
262  st->duration = 0;
263  for (i = 0; i < num_packets; i++) {
264  if (avio_feof(pb))
265  return AVERROR_INVALIDDATA;
266  ret = av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME);
267  if (ret < 0)
268  return ret;
271  }
272  }
273 
274  if (avio_tell(pb) - ccount > size) {
275  av_log(s, AV_LOG_ERROR, "error reading packet table\n");
276  return AVERROR_INVALIDDATA;
277  }
278  avio_seek(pb, ccount + size, SEEK_SET);
279 
280  caf->num_bytes = pos;
281  return 0;
282 }
283 
284 /** Read information chunk */
285 static void read_info_chunk(AVFormatContext *s, int64_t size)
286 {
287  AVIOContext *pb = s->pb;
288  unsigned int i;
289  unsigned int nb_entries = avio_rb32(pb);
290  for (i = 0; i < nb_entries && !avio_feof(pb); i++) {
291  char key[32];
292  char value[1024];
293  avio_get_str(pb, INT_MAX, key, sizeof(key));
294  avio_get_str(pb, INT_MAX, value, sizeof(value));
295  if (!*key)
296  continue;
297  av_dict_set(&s->metadata, key, value, 0);
298  }
299 }
300 
302 {
303  AVIOContext *pb = s->pb;
304  CafContext *caf = s->priv_data;
305  AVStream *st;
306  uint32_t tag = 0;
307  int found_data, ret;
308  int64_t size, pos;
309 
310  avio_skip(pb, 8); /* magic, version, file flags */
311 
312  /* audio description chunk */
313  if (avio_rb32(pb) != MKBETAG('d','e','s','c')) {
314  av_log(s, AV_LOG_ERROR, "desc chunk not present\n");
315  return AVERROR_INVALIDDATA;
316  }
317  size = avio_rb64(pb);
318  if (size != 32)
319  return AVERROR_INVALIDDATA;
320 
321  ret = read_desc_chunk(s);
322  if (ret)
323  return ret;
324  st = s->streams[0];
325 
326  /* parse each chunk */
327  found_data = 0;
328  while (!avio_feof(pb)) {
329 
330  /* stop at data chunk if seeking is not supported or
331  data chunk size is unknown */
332  if (found_data && (caf->data_size < 0 || !(pb->seekable & AVIO_SEEKABLE_NORMAL)))
333  break;
334 
335  tag = avio_rb32(pb);
336  size = avio_rb64(pb);
337  pos = avio_tell(pb);
338  if (avio_feof(pb))
339  break;
340 
341  switch (tag) {
342  case MKBETAG('d','a','t','a'):
343  avio_skip(pb, 4); /* edit count */
344  caf->data_start = avio_tell(pb);
345  caf->data_size = size < 0 ? -1 : size - 4;
346  if (caf->data_size > 0 && (pb->seekable & AVIO_SEEKABLE_NORMAL))
347  avio_skip(pb, caf->data_size);
348  found_data = 1;
349  break;
350 
351  case MKBETAG('c','h','a','n'):
352  if ((ret = ff_mov_read_chan(s, s->pb, st, size)) < 0)
353  return ret;
354  break;
355 
356  /* magic cookie chunk */
357  case MKBETAG('k','u','k','i'):
358  if (read_kuki_chunk(s, size))
359  return AVERROR_INVALIDDATA;
360  break;
361 
362  /* packet table chunk */
363  case MKBETAG('p','a','k','t'):
364  if (read_pakt_chunk(s, size))
365  return AVERROR_INVALIDDATA;
366  break;
367 
368  case MKBETAG('i','n','f','o'):
370  break;
371 
372  default:
374  "skipping CAF chunk: %08"PRIX32" (%s), size %"PRId64"\n",
376  case MKBETAG('f','r','e','e'):
377  if (size < 0 && found_data)
378  goto found_data;
379  if (size < 0)
380  return AVERROR_INVALIDDATA;
381  break;
382  }
383 
384  if (size > 0 && (pb->seekable & AVIO_SEEKABLE_NORMAL)) {
385  if (pos > INT64_MAX - size)
386  return AVERROR_INVALIDDATA;
387  avio_seek(pb, pos + size, SEEK_SET);
388  }
389  }
390 
391  if (!found_data)
392  return AVERROR_INVALIDDATA;
393 
394 found_data:
395  if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) {
396  if (caf->data_size > 0 && caf->data_size / caf->bytes_per_packet < INT64_MAX / caf->frames_per_packet)
397  st->nb_frames = (caf->data_size / caf->bytes_per_packet) * caf->frames_per_packet;
398  } else if (ffstream(st)->nb_index_entries && st->duration > 0) {
399  if (st->codecpar->sample_rate && caf->data_size / st->duration > INT64_MAX / st->codecpar->sample_rate / 8) {
400  av_log(s, AV_LOG_ERROR, "Overflow during bit rate calculation %d * 8 * %"PRId64"\n",
401  st->codecpar->sample_rate, caf->data_size / st->duration);
402  return AVERROR_INVALIDDATA;
403  }
404  st->codecpar->bit_rate = st->codecpar->sample_rate * 8LL *
405  (caf->data_size / st->duration);
406  } else {
407  av_log(s, AV_LOG_ERROR, "Missing packet table. It is required when "
408  "block size or frame size are variable.\n");
409  return AVERROR_INVALIDDATA;
410  }
411 
412  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
413  st->start_time = 0;
414 
415  /* position the stream at the start of data */
416  if (caf->data_size >= 0)
417  avio_seek(pb, caf->data_start, SEEK_SET);
418 
419  return 0;
420 }
421 
422 #define CAF_MAX_PKT_SIZE 4096
423 
425 {
426  AVIOContext *pb = s->pb;
427  AVStream *st = s->streams[0];
428  FFStream *const sti = ffstream(st);
429  CafContext *caf = s->priv_data;
430  int res, pkt_size = 0, pkt_frames = 0;
431  int64_t left = CAF_MAX_PKT_SIZE;
432 
433  if (avio_feof(pb))
434  return AVERROR_EOF;
435 
436  /* don't read past end of data chunk */
437  if (caf->data_size > 0) {
438  left = (caf->data_start + caf->data_size) - avio_tell(pb);
439  if (!left)
440  return AVERROR_EOF;
441  if (left < 0)
442  return AVERROR(EIO);
443  }
444 
445  pkt_frames = caf->frames_per_packet;
446  pkt_size = caf->bytes_per_packet;
447 
448  if (pkt_size > 0 && pkt_frames == 1) {
449  pkt_size = (CAF_MAX_PKT_SIZE / pkt_size) * pkt_size;
450  pkt_size = FFMIN(pkt_size, left);
451  pkt_frames = pkt_size / caf->bytes_per_packet;
452  } else if (sti->nb_index_entries) {
453  if (caf->packet_cnt < sti->nb_index_entries - 1) {
454  pkt_size = sti->index_entries[caf->packet_cnt + 1].pos - sti->index_entries[caf->packet_cnt].pos;
455  pkt_frames = sti->index_entries[caf->packet_cnt + 1].timestamp - sti->index_entries[caf->packet_cnt].timestamp;
456  } else if (caf->packet_cnt == sti->nb_index_entries - 1) {
457  pkt_size = caf->num_bytes - sti->index_entries[caf->packet_cnt].pos;
458  pkt_frames = st->duration - sti->index_entries[caf->packet_cnt].timestamp;
459  } else {
460  return AVERROR(EIO);
461  }
462  }
463 
464  if (pkt_size == 0 || pkt_frames == 0 || pkt_size > left)
465  return AVERROR(EIO);
466 
467  res = av_get_packet(pb, pkt, pkt_size);
468  if (res < 0)
469  return res;
470 
471  pkt->size = res;
472  pkt->stream_index = 0;
473  pkt->dts = pkt->pts = caf->frame_cnt;
474 
475  caf->packet_cnt++;
476  caf->frame_cnt += pkt_frames;
477 
478  return 0;
479 }
480 
481 static int read_seek(AVFormatContext *s, int stream_index,
482  int64_t timestamp, int flags)
483 {
484  AVStream *st = s->streams[0];
485  FFStream *const sti = ffstream(st);
486  CafContext *caf = s->priv_data;
487  int64_t pos, packet_cnt, frame_cnt;
488 
489  timestamp = FFMAX(timestamp, 0);
490 
491  if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) {
492  /* calculate new byte position based on target frame position */
493  pos = caf->bytes_per_packet * (timestamp / caf->frames_per_packet);
494  if (caf->data_size > 0)
495  pos = FFMIN(pos, caf->data_size);
496  packet_cnt = pos / caf->bytes_per_packet;
497  frame_cnt = caf->frames_per_packet * packet_cnt;
498  } else if (sti->nb_index_entries) {
499  packet_cnt = av_index_search_timestamp(st, timestamp, flags);
500  frame_cnt = sti->index_entries[packet_cnt].timestamp;
501  pos = sti->index_entries[packet_cnt].pos;
502  } else {
503  return -1;
504  }
505 
506  if (avio_seek(s->pb, pos + caf->data_start, SEEK_SET) < 0)
507  return -1;
508 
509  caf->packet_cnt = packet_cnt;
510  caf->frame_cnt = frame_cnt;
511 
512  return 0;
513 }
514 
516  .name = "caf",
517  .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"),
518  .priv_data_size = sizeof(CafContext),
519  .read_probe = probe,
522  .read_seek = read_seek,
523  .codec_tag = ff_caf_codec_tags_list,
524 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
CafContext::packet_cnt
int64_t packet_cnt
packet counter
Definition: cafdec.c:46
read_info_chunk
static void read_info_chunk(AVFormatContext *s, int64_t size)
Read information chunk.
Definition: cafdec.c:285
caf.h
CAF_MAX_PKT_SIZE
#define CAF_MAX_PKT_SIZE
Definition: cafdec.c:422
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
av_int2double
static av_always_inline double av_int2double(uint64_t i)
Reinterpret a 64-bit integer as a double.
Definition: intfloat.h:60
AV_CODEC_ID_ALAC
@ AV_CODEC_ID_ALAC
Definition: codec_id.h:459
AVIOContext::error
int error
contains the error code or 0 if no error happened
Definition: avio.h:249
FLAC_METADATA_TYPE_STREAMINFO
@ FLAC_METADATA_TYPE_STREAMINFO
Definition: flac.h:46
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:59
AV_CODEC_ID_FLAC
@ AV_CODEC_ID_FLAC
Definition: codec_id.h:455
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:323
intfloat.h
AVIndexEntry
Definition: avformat.h:700
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:708
ff_get_extradata
int ff_get_extradata(void *logctx, 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: demux_utils.c:355
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:464
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:843
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:423
av_add_index_entry
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: seek.c:120
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:513
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
ff_caf_demuxer
const AVInputFormat ff_caf_demuxer
Definition: cafdec.c:515
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:900
read_desc_chunk
static int read_desc_chunk(AVFormatContext *s)
Read audio description chunk.
Definition: cafdec.c:67
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:808
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:549
ff_mov_read_esds
int ff_mov_read_esds(AVFormatContext *fc, AVIOContext *pb)
Definition: mov_esds.c:23
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:554
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:702
key
const char * key
Definition: hwcontext_opencl.c:179
CafContext::data_size
int64_t data_size
raw data size, in bytes
Definition: cafdec.c:50
ff_mov_get_lpcm_codec_id
static enum AVCodecID ff_mov_get_lpcm_codec_id(int bps, int flags)
Compute codec id for 'lpcm' tag.
Definition: isom.h:438
AVFormatContext
Format I/O context.
Definition: avformat.h:1363
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_header
static int read_header(AVFormatContext *s)
Definition: cafdec.c:301
isom.h
flac_parse_block_header
static av_always_inline void flac_parse_block_header(const uint8_t *block_header, int *last, int *type, int *size)
Parse the metadata block parameters from the header.
Definition: flac.h:63
ALAC_PREAMBLE
#define ALAC_PREAMBLE
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:955
CafContext::data_start
int64_t data_start
data start position, in bytes
Definition: cafdec.c:49
FFStream::nb_index_entries
int nb_index_entries
Definition: internal.h:257
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
FLAC_STREAMINFO_SIZE
#define FLAC_STREAMINFO_SIZE
Definition: flac.h:32
read_kuki_chunk
static int read_kuki_chunk(AVFormatContext *s, int64_t size)
Read magic cookie chunk.
Definition: cafdec.c:110
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:206
CafContext::num_bytes
int64_t num_bytes
total number of bytes in stream
Definition: cafdec.c:44
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:171
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:902
AV_WB32
#define AV_WB32(p, v)
Definition: intreadwrite.h:417
AV_CODEC_ID_AAC
@ AV_CODEC_ID_AAC
Definition: codec_id.h:445
read_seek
static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: cafdec.c:481
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:777
ALAC_NEW_KUKI
#define ALAC_NEW_KUKI
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:801
AVPacket::size
int size
Definition: packet.h:523
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:106
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:145
AVIOContext::seekable
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:271
FFStream
Definition: internal.h:199
av_bswap32
#define av_bswap32
Definition: bswap.h:28
CafContext::bytes_per_packet
int bytes_per_packet
bytes in a packet, or 0 if variable
Definition: cafdec.c:42
avio_get_str
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:913
size
int size
Definition: twinvq_data.h:10344
CafContext::frames_per_packet
int frames_per_packet
frames in a packet, or 0 if variable
Definition: cafdec.c:43
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: macros.h:56
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
AV_CODEC_ID_OPUS
@ AV_CODEC_ID_OPUS
Definition: codec_id.h:503
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:521
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:650
ff_mp4_read_descr_len
int ff_mp4_read_descr_len(AVIOContext *pb)
Definition: isom.c:282
CafContext
Definition: cafdec.c:41
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:515
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:178
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
ff_codec_caf_tags
const AVCodecTag ff_codec_caf_tags[]
Known codec tags for CAF.
Definition: caf.c:34
demux.h
av_get_packet
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:103
mov_chan.h
tag
uint32_t tag
Definition: movenc.c:1786
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:841
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:278
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
dict.h
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
ff_caf_codec_tags_list
const AVCodecTag *const ff_caf_codec_tags_list[]
Definition: caf.c:82
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:659
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:701
AVPacket::stream_index
int stream_index
Definition: packet.h:524
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:365
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:255
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:97
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
av_dict_set
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:88
CafContext::frame_cnt
int64_t frame_cnt
frame counter
Definition: cafdec.c:47
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: cafdec.c:424
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:84
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:890
probe
static int probe(const AVProbeData *p)
Definition: cafdec.c:53
flac.h
ALAC_HEADER
#define ALAC_HEADER
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
AV_RB64
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_RB64
Definition: bytestream.h:95
av_clipd
av_clipd
Definition: af_crystalizer.c:131
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98
av_fourcc2str
#define av_fourcc2str(fourcc)
Definition: avutil.h:358
ff_mov_read_chan
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:496
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:243
ff_alloc_extradata
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:239
read_pakt_chunk
static int read_pakt_chunk(AVFormatContext *s, int64_t size)
Read packet table chunk.
Definition: cafdec.c:239
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:393