Libav
gxf.c
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1 /*
2  * GXF demuxer.
3  * Copyright (c) 2006 Reimar Doeffinger
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <inttypes.h>
23 
25 #include "libavutil/common.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "gxf.h"
29 #include "libavcodec/mpeg12data.h"
30 
32  int64_t first_field;
33  int64_t last_field;
36 };
37 
45 static int parse_packet_header(AVIOContext *pb, GXFPktType *type, int *length) {
46  if (avio_rb32(pb))
47  return 0;
48  if (avio_r8(pb) != 1)
49  return 0;
50  *type = avio_r8(pb);
51  *length = avio_rb32(pb);
52  if ((*length >> 24) || *length < 16)
53  return 0;
54  *length -= 16;
55  if (avio_rb32(pb))
56  return 0;
57  if (avio_r8(pb) != 0xe1)
58  return 0;
59  if (avio_r8(pb) != 0xe2)
60  return 0;
61  return 1;
62 }
63 
67 static int gxf_probe(AVProbeData *p) {
68  static const uint8_t startcode[] = {0, 0, 0, 0, 1, 0xbc}; // start with map packet
69  static const uint8_t endcode[] = {0, 0, 0, 0, 0xe1, 0xe2};
70  if (!memcmp(p->buf, startcode, sizeof(startcode)) &&
71  !memcmp(&p->buf[16 - sizeof(endcode)], endcode, sizeof(endcode)))
72  return AVPROBE_SCORE_MAX;
73  return 0;
74 }
75 
82 static int get_sindex(AVFormatContext *s, int id, int format) {
83  int i;
84  AVStream *st = NULL;
85  i = ff_find_stream_index(s, id);
86  if (i >= 0)
87  return i;
88  st = avformat_new_stream(s, NULL);
89  if (!st)
90  return AVERROR(ENOMEM);
91  st->id = id;
92  switch (format) {
93  case 3:
94  case 4:
97  break;
98  case 13:
99  case 15:
102  break;
103  case 14:
104  case 16:
107  break;
108  case 11:
109  case 12:
110  case 20:
113  st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
114  break;
115  case 22:
116  case 23:
119  st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
120  break;
121  case 9:
124  st->codec->channels = 1;
126  st->codec->sample_rate = 48000;
127  st->codec->bit_rate = 3 * 1 * 48000 * 8;
128  st->codec->block_align = 3 * 1;
129  st->codec->bits_per_coded_sample = 24;
130  break;
131  case 10:
134  st->codec->channels = 1;
136  st->codec->sample_rate = 48000;
137  st->codec->bit_rate = 2 * 1 * 48000 * 8;
138  st->codec->block_align = 2 * 1;
139  st->codec->bits_per_coded_sample = 16;
140  break;
141  case 17:
144  st->codec->channels = 2;
146  st->codec->sample_rate = 48000;
147  break;
148  // timecode tracks:
149  case 7:
150  case 8:
151  case 24:
154  break;
155  default:
158  break;
159  }
160  return s->nb_streams - 1;
161 }
162 
168 static void gxf_material_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) {
171  while (*len >= 2) {
172  GXFMatTag tag = avio_r8(pb);
173  int tlen = avio_r8(pb);
174  *len -= 2;
175  if (tlen > *len)
176  return;
177  *len -= tlen;
178  if (tlen == 4) {
179  uint32_t value = avio_rb32(pb);
180  if (tag == MAT_FIRST_FIELD)
181  si->first_field = value;
182  else if (tag == MAT_LAST_FIELD)
183  si->last_field = value;
184  } else
185  avio_skip(pb, tlen);
186  }
187 }
188 
189 static const AVRational frame_rate_tab[] = {
190  { 60, 1},
191  {60000, 1001},
192  { 50, 1},
193  { 30, 1},
194  {30000, 1001},
195  { 25, 1},
196  { 24, 1},
197  {24000, 1001},
198  { 0, 0},
199 };
200 
207  if (fps < 1 || fps > 9) fps = 9;
208  return frame_rate_tab[fps - 1];
209 }
210 
216 static AVRational fps_umf2avr(uint32_t flags) {
217  static const AVRational map[] = {{50, 1}, {60000, 1001}, {24, 1},
218  {25, 1}, {30000, 1001}};
219  int idx = av_log2((flags & 0x7c0) >> 6);
220  return map[idx];
221 }
222 
228 static void gxf_track_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) {
229  si->frames_per_second = (AVRational){0, 0};
230  si->fields_per_frame = 0;
231  while (*len >= 2) {
232  GXFTrackTag tag = avio_r8(pb);
233  int tlen = avio_r8(pb);
234  *len -= 2;
235  if (tlen > *len)
236  return;
237  *len -= tlen;
238  if (tlen == 4) {
239  uint32_t value = avio_rb32(pb);
240  if (tag == TRACK_FPS)
241  si->frames_per_second = fps_tag2avr(value);
242  else if (tag == TRACK_FPF && (value == 1 || value == 2))
243  si->fields_per_frame = value;
244  } else
245  avio_skip(pb, tlen);
246  }
247 }
248 
252 static void gxf_read_index(AVFormatContext *s, int pkt_len) {
253  AVIOContext *pb = s->pb;
254  AVStream *st = s->streams[0];
255  uint32_t fields_per_map = avio_rl32(pb);
256  uint32_t map_cnt = avio_rl32(pb);
257  int i;
258  pkt_len -= 8;
259  if (s->flags & AVFMT_FLAG_IGNIDX) {
260  avio_skip(pb, pkt_len);
261  return;
262  }
263  if (map_cnt > 1000) {
264  av_log(s, AV_LOG_ERROR,
265  "too many index entries %"PRIu32" (%"PRIx32")\n",
266  map_cnt, map_cnt);
267  map_cnt = 1000;
268  }
269  if (pkt_len < 4 * map_cnt) {
270  av_log(s, AV_LOG_ERROR, "invalid index length\n");
271  avio_skip(pb, pkt_len);
272  return;
273  }
274  pkt_len -= 4 * map_cnt;
275  av_add_index_entry(st, 0, 0, 0, 0, 0);
276  for (i = 0; i < map_cnt; i++)
277  av_add_index_entry(st, (uint64_t)avio_rl32(pb) * 1024,
278  i * (uint64_t)fields_per_map + 1, 0, 0, 0);
279  avio_skip(pb, pkt_len);
280 }
281 
282 static int gxf_header(AVFormatContext *s) {
283  AVIOContext *pb = s->pb;
284  GXFPktType pkt_type;
285  int map_len;
286  int len;
287  AVRational main_timebase = {0, 0};
288  struct gxf_stream_info *si = s->priv_data;
289  int i;
290  if (!parse_packet_header(pb, &pkt_type, &map_len) || pkt_type != PKT_MAP) {
291  av_log(s, AV_LOG_ERROR, "map packet not found\n");
292  return 0;
293  }
294  map_len -= 2;
295  if (avio_r8(pb) != 0x0e0 || avio_r8(pb) != 0xff) {
296  av_log(s, AV_LOG_ERROR, "unknown version or invalid map preamble\n");
297  return 0;
298  }
299  map_len -= 2;
300  len = avio_rb16(pb); // length of material data section
301  if (len > map_len) {
302  av_log(s, AV_LOG_ERROR, "material data longer than map data\n");
303  return 0;
304  }
305  map_len -= len;
306  gxf_material_tags(pb, &len, si);
307  avio_skip(pb, len);
308  map_len -= 2;
309  len = avio_rb16(pb); // length of track description
310  if (len > map_len) {
311  av_log(s, AV_LOG_ERROR, "track description longer than map data\n");
312  return 0;
313  }
314  map_len -= len;
315  while (len > 0) {
316  int track_type, track_id, track_len;
317  AVStream *st;
318  int idx;
319  len -= 4;
320  track_type = avio_r8(pb);
321  track_id = avio_r8(pb);
322  track_len = avio_rb16(pb);
323  len -= track_len;
324  gxf_track_tags(pb, &track_len, si);
325  avio_skip(pb, track_len);
326  if (!(track_type & 0x80)) {
327  av_log(s, AV_LOG_ERROR, "invalid track type %x\n", track_type);
328  continue;
329  }
330  track_type &= 0x7f;
331  if ((track_id & 0xc0) != 0xc0) {
332  av_log(s, AV_LOG_ERROR, "invalid track id %x\n", track_id);
333  continue;
334  }
335  track_id &= 0x3f;
336  idx = get_sindex(s, track_id, track_type);
337  if (idx < 0) continue;
338  st = s->streams[idx];
339  if (!main_timebase.num || !main_timebase.den) {
340  main_timebase.num = si->frames_per_second.den;
341  main_timebase.den = si->frames_per_second.num * 2;
342  }
343  st->start_time = si->first_field;
345  st->duration = si->last_field - si->first_field;
346  }
347  if (len < 0)
348  av_log(s, AV_LOG_ERROR, "invalid track description length specified\n");
349  if (map_len)
350  avio_skip(pb, map_len);
351  if (!parse_packet_header(pb, &pkt_type, &len)) {
352  av_log(s, AV_LOG_ERROR, "sync lost in header\n");
353  return -1;
354  }
355  if (pkt_type == PKT_FLT) {
356  gxf_read_index(s, len);
357  if (!parse_packet_header(pb, &pkt_type, &len)) {
358  av_log(s, AV_LOG_ERROR, "sync lost in header\n");
359  return -1;
360  }
361  }
362  if (pkt_type == PKT_UMF) {
363  if (len >= 0x39) {
364  AVRational fps;
365  len -= 0x39;
366  avio_skip(pb, 5); // preamble
367  avio_skip(pb, 0x30); // payload description
368  fps = fps_umf2avr(avio_rl32(pb));
369  if (!main_timebase.num || !main_timebase.den) {
370  // this may not always be correct, but simply the best we can get
371  main_timebase.num = fps.den;
372  main_timebase.den = fps.num * 2;
373  }
374  } else
375  av_log(s, AV_LOG_INFO, "UMF packet too short\n");
376  } else
377  av_log(s, AV_LOG_INFO, "UMF packet missing\n");
378  avio_skip(pb, len);
379  // set a fallback value, 60000/1001 is specified for audio-only files
380  // so use that regardless of why we do not know the video frame rate.
381  if (!main_timebase.num || !main_timebase.den)
382  main_timebase = (AVRational){1001, 60000};
383  for (i = 0; i < s->nb_streams; i++) {
384  AVStream *st = s->streams[i];
385  avpriv_set_pts_info(st, 32, main_timebase.num, main_timebase.den);
386  }
387  return 0;
388 }
389 
390 #define READ_ONE() \
391  { \
392  if (!max_interval-- || pb->eof_reached) \
393  goto out; \
394  tmp = tmp << 8 | avio_r8(pb); \
395  }
396 
404 static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp) {
405  uint32_t tmp;
406  uint64_t last_pos;
407  uint64_t last_found_pos = 0;
408  int cur_track;
409  int64_t cur_timestamp = AV_NOPTS_VALUE;
410  int len;
411  AVIOContext *pb = s->pb;
412  GXFPktType type;
413  tmp = avio_rb32(pb);
414 start:
415  while (tmp)
416  READ_ONE();
417  READ_ONE();
418  if (tmp != 1)
419  goto start;
420  last_pos = avio_tell(pb);
421  if (avio_seek(pb, -5, SEEK_CUR) < 0)
422  goto out;
423  if (!parse_packet_header(pb, &type, &len) || type != PKT_MEDIA) {
424  if (avio_seek(pb, last_pos, SEEK_SET) < 0)
425  goto out;
426  goto start;
427  }
428  avio_r8(pb);
429  cur_track = avio_r8(pb);
430  cur_timestamp = avio_rb32(pb);
431  last_found_pos = avio_tell(pb) - 16 - 6;
432  if ((track >= 0 && track != cur_track) || (timestamp >= 0 && timestamp > cur_timestamp)) {
433  if (avio_seek(pb, last_pos, SEEK_SET) >= 0)
434  goto start;
435  }
436 out:
437  if (last_found_pos)
438  avio_seek(pb, last_found_pos, SEEK_SET);
439  return cur_timestamp;
440 }
441 
442 static int gxf_packet(AVFormatContext *s, AVPacket *pkt) {
443  AVIOContext *pb = s->pb;
444  GXFPktType pkt_type;
445  int pkt_len;
446  struct gxf_stream_info *si = s->priv_data;
447 
448  while (!pb->eof_reached) {
449  AVStream *st;
450  int track_type, track_id, ret;
451  int field_nr, field_info, skip = 0;
452  int stream_index;
453  if (!parse_packet_header(pb, &pkt_type, &pkt_len)) {
454  if (!pb->eof_reached)
455  av_log(s, AV_LOG_ERROR, "sync lost\n");
456  return -1;
457  }
458  if (pkt_type == PKT_FLT) {
459  gxf_read_index(s, pkt_len);
460  continue;
461  }
462  if (pkt_type != PKT_MEDIA) {
463  avio_skip(pb, pkt_len);
464  continue;
465  }
466  if (pkt_len < 16) {
467  av_log(s, AV_LOG_ERROR, "invalid media packet length\n");
468  continue;
469  }
470  pkt_len -= 16;
471  track_type = avio_r8(pb);
472  track_id = avio_r8(pb);
473  stream_index = get_sindex(s, track_id, track_type);
474  if (stream_index < 0)
475  return stream_index;
476  st = s->streams[stream_index];
477  field_nr = avio_rb32(pb);
478  field_info = avio_rb32(pb);
479  avio_rb32(pb); // "timeline" field number
480  avio_r8(pb); // flags
481  avio_r8(pb); // reserved
482  if (st->codec->codec_id == AV_CODEC_ID_PCM_S24LE ||
484  int first = field_info >> 16;
485  int last = field_info & 0xffff; // last is exclusive
486  int bps = av_get_bits_per_sample(st->codec->codec_id)>>3;
487  if (first <= last && last*bps <= pkt_len) {
488  avio_skip(pb, first*bps);
489  skip = pkt_len - last*bps;
490  pkt_len = (last-first)*bps;
491  } else
492  av_log(s, AV_LOG_ERROR, "invalid first and last sample values\n");
493  }
494  ret = av_get_packet(pb, pkt, pkt_len);
495  if (skip)
496  avio_skip(pb, skip);
497  pkt->stream_index = stream_index;
498  pkt->dts = field_nr;
499 
500  //set duration manually for DV or else lavf misdetects the frame rate
501  if (st->codec->codec_id == AV_CODEC_ID_DVVIDEO)
502  pkt->duration = si->fields_per_frame;
503 
504  return ret;
505  }
506  return AVERROR(EIO);
507 }
508 
509 static int gxf_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) {
510  int res = 0;
511  uint64_t pos;
512  uint64_t maxlen = 100 * 1024 * 1024;
513  AVStream *st = s->streams[0];
514  int64_t start_time = s->streams[stream_index]->start_time;
515  int64_t found;
516  int idx;
517  if (timestamp < start_time) timestamp = start_time;
518  idx = av_index_search_timestamp(st, timestamp - start_time,
520  if (idx < 0)
521  return -1;
522  pos = st->index_entries[idx].pos;
523  if (idx < st->nb_index_entries - 2)
524  maxlen = st->index_entries[idx + 2].pos - pos;
525  maxlen = FFMAX(maxlen, 200 * 1024);
526  res = avio_seek(s->pb, pos, SEEK_SET);
527  if (res < 0)
528  return res;
529  found = gxf_resync_media(s, maxlen, -1, timestamp);
530  if (FFABS(found - timestamp) > 4)
531  return -1;
532  return 0;
533 }
534 
535 static int64_t gxf_read_timestamp(AVFormatContext *s, int stream_index,
536  int64_t *pos, int64_t pos_limit) {
537  AVIOContext *pb = s->pb;
538  int64_t res;
539  if (avio_seek(pb, *pos, SEEK_SET) < 0)
540  return AV_NOPTS_VALUE;
541  res = gxf_resync_media(s, pos_limit - *pos, -1, -1);
542  *pos = avio_tell(pb);
543  return res;
544 }
545 
547  .name = "gxf",
548  .long_name = NULL_IF_CONFIG_SMALL("GXF (General eXchange Format)"),
549  .priv_data_size = sizeof(struct gxf_stream_info),
550  .read_probe = gxf_probe,
551  .read_header = gxf_header,
552  .read_packet = gxf_packet,
553  .read_seek = gxf_seek,
554  .read_timestamp = gxf_read_timestamp,
555 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:1609
GXFPktType
Definition: gxf.h:25
static int gxf_packet(AVFormatContext *s, AVPacket *pkt)
Definition: gxf.c:442
Bytestream IO Context.
Definition: avio.h:68
static void gxf_track_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si)
filters out interesting tags from track information.
Definition: gxf.c:228
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:1181
enum AVCodecID id
Definition: mxfenc.c:84
static void gxf_material_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si)
filters out interesting tags from material information.
Definition: gxf.c:168
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:2829
int64_t pos
Definition: avformat.h:660
#define AVSEEK_FLAG_ANY
seek to any frame, even non-keyframes
Definition: avformat.h:1611
int num
numerator
Definition: rational.h:44
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:878
Definition: gxf.h:29
#define AV_CH_LAYOUT_STEREO
static void gxf_read_index(AVFormatContext *s, int pkt_len)
read index from FLT packet into stream 0 av_index
Definition: gxf.c:252
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:580
static int gxf_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: gxf.c:509
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1828
Format I/O context.
Definition: avformat.h:922
#define AVFMT_FLAG_IGNIDX
Ignore index.
Definition: avformat.h:1035
uint8_t
Opaque data information usually continuous.
Definition: avutil.h:189
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:595
enum AVStreamParseType need_parsing
Definition: avformat.h:867
int id
Format-specific stream ID.
Definition: avformat.h:706
Definition: gxf.h:49
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2521
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
int64_t first_field
Definition: gxf.c:32
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1033
static int flags
Definition: log.c:44
uint32_t tag
Definition: movenc.c:844
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:117
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2507
int duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:991
static int parse_packet_header(AVIOContext *pb, GXFPktType *type, int *length)
parses a packet header, extracting type and length
Definition: gxf.c:45
static AVRational fps_umf2avr(uint32_t flags)
convert UMF attributes flags to AVRational fps
Definition: gxf.c:216
#define READ_ONE()
Definition: gxf.c:390
static int64_t start_time
Definition: avplay.c:245
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:2043
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1222
int64_t last_field
Definition: gxf.c:33
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:564
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
AVInputFormat ff_gxf_demuxer
Definition: gxf.c:546
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
Definition: gxf.h:27
#define FFMAX(a, b)
Definition: common.h:55
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1852
Only parse headers, do not repack.
Definition: avformat.h:654
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:443
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:397
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:978
int ff_find_stream_index(AVFormatContext *s, int id)
Find stream index based on format-specific stream ID.
Definition: utils.c:2906
int bit_rate
the average bitrate
Definition: avcodec.h:1114
audio channel layout utility functions
static AVRational fps_tag2avr(int32_t fps)
convert fps tag value to AVRational fps
Definition: gxf.c:206
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
int32_t
static int get_sindex(AVFormatContext *s, int id, int format)
gets the stream index for the track with the specified id, creates new stream if not found ...
Definition: gxf.c:82
#define FFABS(a)
Definition: common.h:52
GXFTrackTag
Definition: gxf.h:42
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:186
int32_t fields_per_frame
Definition: gxf.c:35
preferred ID for MPEG-1/2 video decoding
Definition: avcodec.h:110
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
#define AV_LOG_INFO
Standard information.
Definition: log.h:134
enum AVMediaType codec_type
Definition: avcodec.h:1058
enum AVCodecID codec_id
Definition: avcodec.h:1067
int sample_rate
samples per second
Definition: avcodec.h:1791
AVIOContext * pb
I/O context.
Definition: avformat.h:964
GXFMatTag
Definition: gxf.h:33
MPEG1/2 tables.
rational number numerator/denominator
Definition: rational.h:43
Definition: gxf.h:26
This structure contains the data a format has to probe a file.
Definition: avformat.h:395
static int gxf_header(AVFormatContext *s)
Definition: gxf.c:282
static const AVRational frame_rate_tab[]
Definition: gxf.c:189
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:756
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> out
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:404
Main libavformat public API header.
AVRational frames_per_second
Definition: gxf.c:34
common internal and external API header
static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp)
resync the stream on the next media packet with specified properties
Definition: gxf.c:404
int64_t start_time
Decoding: pts of the first frame of the stream, in stream time base.
Definition: avformat.h:749
int den
denominator
Definition: rational.h:45
unsigned bps
Definition: movenc.c:845
static int64_t gxf_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos, int64_t pos_limit)
Definition: gxf.c:535
static int gxf_probe(AVProbeData *p)
check if file starts with a PKT_MAP header
Definition: gxf.c:67
Definition: gxf.h:30
int eof_reached
true if eof reached
Definition: avio.h:96
int len
int channels
number of audio channels
Definition: avcodec.h:1792
#define av_log2
Definition: intmath.h:85
void * priv_data
Format private data.
Definition: avformat.h:950
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:972
Definition: gxf.h:47
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:525
int stream_index
Definition: avcodec.h:975
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:950
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:228