FFmpeg: libavformat/mvdec.c Source File

FFmpeg
mvdec.c
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1 /*
2  * Silicon Graphics Movie demuxer
3  * Copyright (c) 2012 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Silicon Graphics Movie demuxer
25  */
26 
27 #include "libavutil/channel_layout.h"
28 #include "libavutil/eval.h"
29 #include "libavutil/intfloat.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/mem.h"
32 #include "libavutil/rational.h"
33 
34 #include "avformat.h"
35 #include "demux.h"
36 #include "internal.h"
37 
38  typedef struct MvContext {
39   int nb_video_tracks;
40   int nb_audio_tracks;
41 
42   int eof_count; ///< number of streams that have finished
43   int stream_index; ///< current stream index
44   int frame[2]; ///< frame nb for current stream
45 
46   int acompression; ///< compression level for audio stream
47   int aformat; ///< audio format
48 } MvContext;
49 
50 /* these magic numbers are defined in moviefile.h on Silicon Graphics IRIX */
51  #define MOVIE_SOUND 1
52  #define MOVIE_SILENT 2
53 
54  #define AUDIO_FORMAT_SIGNED 401
55 
56  static int mv_probe(const AVProbeData *p)
57 {
58  if (AV_RB32(p->buf) == MKBETAG('M', 'O', 'V', 'I') &&
59  AV_RB16(p->buf + 4) < 3)
60  return AVPROBE_SCORE_MAX;
61  return 0;
62 }
63 
64  static char *var_read_string(AVIOContext *pb, int size)
65 {
66  int n;
67  char *str;
68 
69  if (size < 0 || size == INT_MAX)
70  return NULL;
71 
72  str = av_malloc(size + 1);
73  if (!str)
74  return NULL;
75  n = avio_get_str(pb, size, str, size + 1);
76  if (n < size)
77  avio_skip(pb, size - n);
78  return str;
79 }
80 
81  static int var_read_int(AVIOContext *pb, int size)
82 {
83  int v;
84  char *s = var_read_string(pb, size);
85  if (!s)
86  return 0;
87  v = strtol(s, NULL, 10);
88  av_free(s);
89  return v;
90 }
91 
92  static AVRational var_read_float(AVIOContext *pb, int size)
93 {
94  AVRational v;
95  char *s = var_read_string(pb, size);
96  if (!s)
97  return (AVRational) { 0, 0 };
98  v = av_d2q(av_strtod(s, NULL), INT_MAX);
99  av_free(s);
100  return v;
101 }
102 
103  static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
104 {
105  char *value = var_read_string(avctx->pb, size);
106  if (value)
107  av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
108 }
109 
110  static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
111 {
112  if (channels <= 0) {
113  av_log(avctx, AV_LOG_ERROR, "Channel count %d invalid.\n", channels);
114  return AVERROR_INVALIDDATA;
115  }
116  av_channel_layout_default(&st->codecpar->ch_layout, channels);
117  return 0;
118 }
119 
120 /**
121  * Parse global variable
122  * @return < 0 if unknown
123  */
124  static int parse_global_var(AVFormatContext *avctx, AVStream *st,
125  const char *name, int size)
126 {
127  MvContext *mv = avctx->priv_data;
128  AVIOContext *pb = avctx->pb;
129  if (!strcmp(name, "__NUM_I_TRACKS")) {
130  mv->nb_video_tracks = var_read_int(pb, size);
131  } else if (!strcmp(name, "__NUM_A_TRACKS")) {
132  mv->nb_audio_tracks = var_read_int(pb, size);
133  } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
134  var_read_metadata(avctx, name, size);
135  } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") ||
136  !strcmp(name, "OPTIMIZED")) {
137  avio_skip(pb, size); // ignore
138  } else
139  return AVERROR_INVALIDDATA;
140 
141  return 0;
142 }
143 
144 /**
145  * Parse audio variable
146  * @return < 0 if unknown
147  */
148  static int parse_audio_var(AVFormatContext *avctx, AVStream *st,
149  const char *name, int size)
150 {
151  MvContext *mv = avctx->priv_data;
152  AVIOContext *pb = avctx->pb;
153  if (!strcmp(name, "__DIR_COUNT")) {
154  st->nb_frames = var_read_int(pb, size);
155  } else if (!strcmp(name, "AUDIO_FORMAT")) {
156  mv->aformat = var_read_int(pb, size);
157  } else if (!strcmp(name, "COMPRESSION")) {
158  mv->acompression = var_read_int(pb, size);
159  } else if (!strcmp(name, "DEFAULT_VOL")) {
160  var_read_metadata(avctx, name, size);
161  } else if (!strcmp(name, "NUM_CHANNELS")) {
162  return set_channels(avctx, st, var_read_int(pb, size));
163  } else if (!strcmp(name, "SAMPLE_RATE")) {
164  int sample_rate = var_read_int(pb, size);
165  if (sample_rate <= 0)
166  return AVERROR_INVALIDDATA;
167  st->codecpar->sample_rate = sample_rate;
168  avpriv_set_pts_info(st, 33, 1, st->codecpar->sample_rate);
169  } else if (!strcmp(name, "SAMPLE_WIDTH")) {
170  uint64_t bpc = var_read_int(pb, size) * (uint64_t)8;
171  if (bpc > 16)
172  return AVERROR_INVALIDDATA;
173  st->codecpar->bits_per_coded_sample = bpc;
174  } else
175  return AVERROR_INVALIDDATA;
176 
177  return 0;
178 }
179 
180 /**
181  * Parse video variable
182  * @return < 0 if unknown
183  */
184  static int parse_video_var(AVFormatContext *avctx, AVStream *st,
185  const char *name, int size)
186 {
187  AVIOContext *pb = avctx->pb;
188  if (!strcmp(name, "__DIR_COUNT")) {
189  st->nb_frames = st->duration = var_read_int(pb, size);
190  } else if (!strcmp(name, "COMPRESSION")) {
191  char *str = var_read_string(pb, size);
192  if (!str)
193  return AVERROR_INVALIDDATA;
194  if (!strcmp(str, "1")) {
195  st->codecpar->codec_id = AV_CODEC_ID_MVC1;
196  } else if (!strcmp(str, "2")) {
197  st->codecpar->format = AV_PIX_FMT_ABGR;
198  st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
199  } else if (!strcmp(str, "3")) {
200  st->codecpar->codec_id = AV_CODEC_ID_SGIRLE;
201  } else if (!strcmp(str, "10")) {
202  st->codecpar->codec_id = AV_CODEC_ID_MJPEG;
203  } else if (!strcmp(str, "MVC2")) {
204  st->codecpar->codec_id = AV_CODEC_ID_MVC2;
205  } else {
206  avpriv_request_sample(avctx, "Video compression %s", str);
207  }
208  av_free(str);
209  } else if (!strcmp(name, "FPS")) {
210  AVRational fps = var_read_float(pb, size);
211  avpriv_set_pts_info(st, 64, fps.den, fps.num);
212  st->avg_frame_rate = fps;
213  } else if (!strcmp(name, "HEIGHT")) {
214  st->codecpar->height = var_read_int(pb, size);
215  } else if (!strcmp(name, "PIXEL_ASPECT")) {
216  st->sample_aspect_ratio = var_read_float(pb, size);
217  av_reduce(&st->sample_aspect_ratio.num, &st->sample_aspect_ratio.den,
218  st->sample_aspect_ratio.num, st->sample_aspect_ratio.den,
219  INT_MAX);
220  } else if (!strcmp(name, "WIDTH")) {
221  st->codecpar->width = var_read_int(pb, size);
222  } else if (!strcmp(name, "ORIENTATION")) {
223  if (var_read_int(pb, size) == 1101) {
224  if (!st->codecpar->extradata) {
225  st->codecpar->extradata = av_strdup("BottomUp");
226  if (!st->codecpar->extradata)
227  return AVERROR(ENOMEM);
228  st->codecpar->extradata_size = 9;
229  }
230  }
231  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
232  var_read_metadata(avctx, name, size);
233  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
234  avio_skip(pb, size); // ignore
235  } else
236  return AVERROR_INVALIDDATA;
237 
238  return 0;
239 }
240 
241  static int read_table(AVFormatContext *avctx, AVStream *st,
242  int (*parse)(AVFormatContext *avctx, AVStream *st,
243  const char *name, int size))
244 {
245  unsigned count;
246  int i;
247 
248  AVIOContext *pb = avctx->pb;
249  avio_skip(pb, 4);
250  count = avio_rb32(pb);
251  avio_skip(pb, 4);
252  for (i = 0; i < count; i++) {
253  char name[17];
254  int size;
255 
256  if (avio_feof(pb))
257  return AVERROR_EOF;
258 
259  if (avio_read(pb, name, 16) != 16)
260  return AVERROR_INVALIDDATA;
261  name[sizeof(name) - 1] = 0;
262  size = avio_rb32(pb);
263  if (size < 0) {
264  av_log(avctx, AV_LOG_ERROR, "entry size %d is invalid\n", size);
265  return AVERROR_INVALIDDATA;
266  }
267  if (parse(avctx, st, name, size) < 0) {
268  avpriv_request_sample(avctx, "Variable %s", name);
269  avio_skip(pb, size);
270  }
271  }
272  return 0;
273 }
274 
275  static void read_index(AVIOContext *pb, AVStream *st)
276 {
277  uint64_t timestamp = 0;
278  int i;
279  for (i = 0; i < st->nb_frames; i++) {
280  uint32_t pos = avio_rb32(pb);
281  uint32_t size = avio_rb32(pb);
282  avio_skip(pb, 8);
283  if (avio_feof(pb))
284  return ;
285  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
286  if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
287  timestamp += size / (st->codecpar->ch_layout.nb_channels * 2LL);
288  } else {
289  timestamp++;
290  }
291  }
292 }
293 
294  static int mv_read_header(AVFormatContext *avctx)
295 {
296  MvContext *mv = avctx->priv_data;
297  AVIOContext *pb = avctx->pb;
298  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
299  int version, i;
300  int ret;
301 
302  avio_skip(pb, 4);
303 
304  version = avio_rb16(pb);
305  if (version == 2) {
306  uint64_t timestamp;
307  int v;
308  uint32_t bytes_per_sample;
309  AVRational fps;
310 
311  avio_skip(pb, 10);
312 
313  fps = av_d2q(av_int2double(avio_rb64(pb)), INT_MAX);
314 
315  /* allocate audio track first to prevent unnecessary seeking
316  * (audio packet always precede video packet for a given frame) */
317  v = avio_rb16(pb);
318  if (v == MOVIE_SOUND) {
319  /* movie has sound so allocate an audio stream */
320  ast = avformat_new_stream(avctx, NULL);
321  if (!ast)
322  return AVERROR(ENOMEM);
323  } else if (v != MOVIE_SILENT)
324  return AVERROR_INVALIDDATA;
325 
326  avio_skip(pb, 2);
327 
328  vst = avformat_new_stream(avctx, NULL);
329  if (!vst)
330  return AVERROR(ENOMEM);
331  avpriv_set_pts_info(vst, 64, fps.den, fps.num);
332  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
333  vst->avg_frame_rate = fps;
334  vst->duration = vst->nb_frames = avio_rb32(pb);
335  v = avio_rb32(pb);
336  switch (v) {
337  case 1:
338  vst->codecpar->codec_id = AV_CODEC_ID_MVC1;
339  break;
340  case 2:
341  vst->codecpar->format = AV_PIX_FMT_ARGB;
342  vst->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
343  break;
344  default:
345  avpriv_request_sample(avctx, "Video compression %i", v);
346  break;
347  }
348  vst->codecpar->codec_tag = 0;
349  vst->codecpar->width = avio_rb32(pb);
350  vst->codecpar->height = avio_rb32(pb);
351  avio_skip(pb, 12);
352 
353  if (ast) {
354  ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
355  ast->nb_frames = vst->nb_frames;
356  ast->codecpar->sample_rate = avio_rb32(pb);
357  if (ast->codecpar->sample_rate <= 0) {
358  av_log(avctx, AV_LOG_ERROR, "Invalid sample rate %d\n", ast->codecpar->sample_rate);
359  return AVERROR_INVALIDDATA;
360  }
361  avpriv_set_pts_info(ast, 33, 1, ast->codecpar->sample_rate);
362 
363  bytes_per_sample = avio_rb32(pb);
364 
365  v = avio_rb32(pb);
366  if (v == AUDIO_FORMAT_SIGNED) {
367  switch (bytes_per_sample) {
368  case 1:
369  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S8;
370  break;
371  case 2:
372  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S16BE;
373  break;
374  default:
375  avpriv_request_sample(avctx, "Audio sample size %i bytes", bytes_per_sample);
376  break;
377  }
378  } else {
379  avpriv_request_sample(avctx, "Audio compression (format %i)", v);
380  }
381 
382  if (bytes_per_sample == 0)
383  return AVERROR_INVALIDDATA;
384 
385  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
386  return AVERROR_INVALIDDATA;
387 
388  avio_skip(pb, 8);
389  } else
390  avio_skip(pb, 24); /* skip meaningless audio metadata */
391 
392  var_read_metadata(avctx, "title", 0x80);
393  var_read_metadata(avctx, "comment", 0x100);
394  avio_skip(pb, 0x80);
395 
396  timestamp = 0;
397  for (i = 0; i < vst->nb_frames; i++) {
398  uint32_t pos = avio_rb32(pb);
399  uint32_t asize = avio_rb32(pb);
400  uint32_t vsize = avio_rb32(pb);
401  if (avio_feof(pb))
402  return AVERROR_INVALIDDATA;
403  avio_skip(pb, 8);
404  if (ast) {
405  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
406  timestamp += asize / (ast->codecpar->ch_layout.nb_channels * (uint64_t)bytes_per_sample);
407  }
408  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
409  }
410  } else if (!version && avio_rb16(pb) == 3) {
411  avio_skip(pb, 4);
412 
413  if ((ret = read_table(avctx, NULL, parse_global_var)) < 0)
414  return ret;
415 
416  if (mv->nb_audio_tracks < 0 || mv->nb_video_tracks < 0 ||
417  (mv->nb_audio_tracks == 0 && mv->nb_video_tracks == 0)) {
418  av_log(avctx, AV_LOG_ERROR, "Stream count is invalid.\n");
419  return AVERROR_INVALIDDATA;
420  }
421 
422  if (mv->nb_audio_tracks > 1) {
423  avpriv_request_sample(avctx, "Multiple audio streams support");
424  return AVERROR_PATCHWELCOME;
425  } else if (mv->nb_audio_tracks) {
426  ast = avformat_new_stream(avctx, NULL);
427  if (!ast)
428  return AVERROR(ENOMEM);
429  ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
430  if ((ret = read_table(avctx, ast, parse_audio_var)) < 0)
431  return ret;
432  if (mv->acompression == 100 &&
433  mv->aformat == AUDIO_FORMAT_SIGNED &&
434  ast->codecpar->bits_per_coded_sample == 16) {
435  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S16BE;
436  } else {
437  avpriv_request_sample(avctx,
438  "Audio compression %i (format %i, sr %i)",
439  mv->acompression, mv->aformat,
440  ast->codecpar->bits_per_coded_sample);
441  ast->codecpar->codec_id = AV_CODEC_ID_NONE;
442  }
443  if (ast->codecpar->ch_layout.nb_channels <= 0) {
444  av_log(avctx, AV_LOG_ERROR, "No valid channel count found.\n");
445  return AVERROR_INVALIDDATA;
446  }
447  }
448 
449  if (mv->nb_video_tracks > 1) {
450  avpriv_request_sample(avctx, "Multiple video streams support");
451  return AVERROR_PATCHWELCOME;
452  } else if (mv->nb_video_tracks) {
453  vst = avformat_new_stream(avctx, NULL);
454  if (!vst)
455  return AVERROR(ENOMEM);
456  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
457  if ((ret = read_table(avctx, vst, parse_video_var))<0)
458  return ret;
459  }
460 
461  if (mv->nb_audio_tracks)
462  read_index(pb, ast);
463 
464  if (mv->nb_video_tracks)
465  read_index(pb, vst);
466  } else {
467  avpriv_request_sample(avctx, "Version %i", version);
468  return AVERROR_PATCHWELCOME;
469  }
470 
471  return 0;
472 }
473 
474  static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
475 {
476  MvContext *mv = avctx->priv_data;
477  AVIOContext *pb = avctx->pb;
478  AVStream *st = avctx->streams[mv->stream_index];
479  FFStream *const sti = ffstream(st);
480  const AVIndexEntry *index;
481  int frame = mv->frame[mv->stream_index];
482  int64_t ret;
483  uint64_t pos;
484 
485  if (frame < sti->nb_index_entries) {
486  index = &sti->index_entries[frame];
487  pos = avio_tell(pb);
488  if (index->pos > pos)
489  avio_skip(pb, index->pos - pos);
490  else if (index->pos < pos) {
491  if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
492  return AVERROR(EIO);
493  ret = avio_seek(pb, index->pos, SEEK_SET);
494  if (ret < 0)
495  return ret;
496  }
497  ret = av_get_packet(pb, pkt, index->size);
498  if (ret < 0)
499  return ret;
500 
501  pkt->stream_index = mv->stream_index;
502  pkt->pts = index->timestamp;
503  pkt->flags |= AV_PKT_FLAG_KEY;
504 
505  mv->frame[mv->stream_index]++;
506  mv->eof_count = 0;
507  } else {
508  mv->eof_count++;
509  if (mv->eof_count >= avctx->nb_streams)
510  return AVERROR_EOF;
511 
512  // avoid returning 0 without a packet
513  return AVERROR(EAGAIN);
514  }
515 
516  mv->stream_index++;
517  if (mv->stream_index >= avctx->nb_streams)
518  mv->stream_index = 0;
519 
520  return 0;
521 }
522 
523  static int mv_read_seek(AVFormatContext *avctx, int stream_index,
524  int64_t timestamp, int flags)
525 {
526  MvContext *mv = avctx->priv_data;
527  AVStream *st = avctx->streams[stream_index];
528  int frame, i;
529 
530  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
531  return AVERROR(ENOSYS);
532 
533  if (!(avctx->pb->seekable & AVIO_SEEKABLE_NORMAL))
534  return AVERROR(EIO);
535 
536  frame = av_index_search_timestamp(st, timestamp, flags);
537  if (frame < 0)
538  return AVERROR_INVALIDDATA;
539 
540  for (i = 0; i < avctx->nb_streams; i++)
541  mv->frame[i] = frame;
542  return 0;
543 }
544 
545  const FFInputFormat ff_mv_demuxer = {
546  .p.name = "mv",
547  .p.long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
548  .priv_data_size = sizeof(MvContext),
549  .read_probe = mv_probe,
550  .read_header = mv_read_header,
551  .read_packet = mv_read_packet,
552  .read_seek = mv_read_seek,
553 };
flags
const SwsFlags flags[]
Definition: swscale.c:61
MvContext::nb_video_tracks
int nb_video_tracks
Definition: mvdec.c:39
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
name
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 minimum maximum flags name is the option name
Definition: writing_filters.txt:88
MvContext::eof_count
int eof_count
number of streams that have finished
Definition: mvdec.c:42
MvContext::frame
int frame[2]
frame nb for current stream
Definition: mvdec.c:44
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
AVSEEK_FLAG_FRAME
#define AVSEEK_FLAG_FRAME
seeking based on frame number
Definition: avformat.h:2377
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
var_read_string
static char * var_read_string(AVIOContext *pb, int size)
Definition: mvdec.c:64
av_int2double
static av_always_inline double av_int2double(uint64_t i)
Reinterpret a 64-bit integer as a double.
Definition: intfloat.h:60
set_channels
static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
Definition: mvdec.c:110
rational.h
int64_t
long long int64_t
Definition: coverity.c:34
mv
static const int8_t mv[256][2]
Definition: 4xm.c:81
AV_CODEC_ID_RAWVIDEO
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:65
AV_CODEC_ID_MVC2
@ AV_CODEC_ID_MVC2
Definition: codec_id.h:239
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1332
AVStream::avg_frame_rate
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:833
AVSEEK_FLAG_BYTE
#define AVSEEK_FLAG_BYTE
seeking based on position in bytes
Definition: avformat.h:2375
MOVIE_SILENT
#define MOVIE_SILENT
Definition: mvdec.c:52
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:329
intfloat.h
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:643
AVIndexEntry
Definition: avformat.h:598
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:606
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
return
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a it should return
Definition: filter_design.txt:265
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:777
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:347
AV_CODEC_ID_PCM_S16BE
@ AV_CODEC_ID_PCM_S16BE
Definition: codec_id.h:338
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
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:122
AUDIO_FORMAT_SIGNED
#define AUDIO_FORMAT_SIGNED
Definition: mvdec.c:54
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:803
var_read_int
static int var_read_int(AVIOContext *pb, int size)
Definition: mvdec.c:81
av_reduce
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
AVRational::num
int num
Numerator.
Definition: rational.h:59
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:79
AV_CODEC_ID_PCM_S8
@ AV_CODEC_ID_PCM_S8
Definition: codec_id.h:341
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:764
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:210
AVFormatContext::metadata
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1496
MvContext::aformat
int aformat
audio format
Definition: mvdec.c:47
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
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:549
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:201
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
channels
channels
Definition: aptx.h:31
AVFormatContext
Format I/O context.
Definition: avformat.h:1264
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:767
parse_audio_var
static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse audio variable.
Definition: mvdec.c:148
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
var_read_metadata
static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
Definition: mvdec.c:103
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
mv_read_packet
static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: mvdec.c:474
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:911
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1306
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
parse_video_var
static int parse_video_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse video variable.
Definition: mvdec.c:184
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
parse_global_var
static int parse_global_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse global variable.
Definition: mvdec.c:124
parse
static int parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: apv_parser.c:46
AV_PIX_FMT_ABGR
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:101
MvContext::stream_index
int stream_index
current stream index
Definition: mvdec.c:43
index
int index
Definition: gxfenc.c:90
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:805
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1320
MOVIE_SOUND
#define MOVIE_SOUND
Definition: mvdec.c:51
eval.h
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
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:94
AVIOContext::seekable
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:261
FFStream
Definition: internal.h:128
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:869
size
int size
Definition: twinvq_data.h:10344
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
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:822
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:51
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:594
read_header
static int read_header(FFV1Context *f, RangeCoder *c)
Definition: ffv1dec.c:498
mv_probe
static int mv_probe(const AVProbeData *p)
Definition: mvdec.c:56
version
version
Definition: libkvazaar.c:313
AV_PIX_FMT_ARGB
@ AV_PIX_FMT_ARGB
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:99
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:839
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:59
mv_read_seek
static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t timestamp, int flags)
Definition: mvdec.c:523
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:581
AVCodecParameters::height
int height
Definition: codec_par.h:135
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
av_d2q
AVRational av_d2q(double d, int max)
Convert a double precision floating point number to a rational.
Definition: rational.c:106
demux.h
MvContext
Definition: mvdec.c:38
AV_CODEC_ID_MVC1
@ AV_CODEC_ID_MVC1
Definition: codec_id.h:238
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:98
read_index
static void read_index(AVIOContext *pb, AVStream *st)
Definition: mvdec.c:275
tag
uint32_t tag
Definition: movenc.c:1995
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:744
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:236
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:265
av_strtod
double av_strtod(const char *numstr, char **tail)
Parse the string in numstr and return its value as a double.
Definition: eval.c:107
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:749
pos
unsigned int pos
Definition: spdifenc.c:414
avformat.h
mv_read_header
static int mv_read_header(AVFormatContext *avctx)
Definition: mvdec.c:294
channel_layout.h
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
AVRational::den
int den
Denominator.
Definition: rational.h:60
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:615
Windows::Graphics::DirectX::Direct3D11::p
IDirect3DDxgiInterfaceAccess _COM_Outptr_ void ** p
Definition: vsrc_gfxcapture_winrt.hpp:53
AVPacket::stream_index
int stream_index
Definition: packet.h:590
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:321
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:184
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:272
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:200
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
mem.h
MvContext::nb_audio_tracks
int nb_audio_tracks
Definition: mvdec.c:40
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
AVCodecParameters::format
int format
Definition: codec_par.h:92
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
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:565
MvContext::acompression
int acompression
compression level for audio stream
Definition: mvdec.c:46
AV_CODEC_ID_SGIRLE
@ AV_CODEC_ID_SGIRLE
Definition: codec_id.h:237
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:86
FFInputFormat
Definition: demux.h:47
read_table
static int read_table(AVFormatContext *avctx, AVStream *st, int(*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
Definition: mvdec.c:241
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
var_read_float
static AVRational var_read_float(AVIOContext *pb, int size)
Definition: mvdec.c:92
ff_mv_demuxer
const FFInputFormat ff_mv_demuxer
Definition: mvdec.c:545
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1292
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_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:245
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:349
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