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/rational.h"
32 
33 #include "avformat.h"
34 #include "internal.h"
35 
36  typedef struct MvContext {
37   int nb_video_tracks;
38   int nb_audio_tracks;
39 
40   int eof_count; ///< number of streams that have finished
41   int stream_index; ///< current stream index
42   int frame[2]; ///< frame nb for current stream
43 
44   int acompression; ///< compression level for audio stream
45   int aformat; ///< audio format
46 } MvContext;
47 
48 /* these magic numbers are defined in moviefile.h on Silicon Grahpics IRIX */
49  #define MOVIE_SOUND 1
50  #define MOVIE_SILENT 2
51 
52  #define AUDIO_FORMAT_SIGNED 401
53 
54  static int mv_probe(const AVProbeData *p)
55 {
56  if (AV_RB32(p->buf) == MKBETAG('M', 'O', 'V', 'I') &&
57  AV_RB16(p->buf + 4) < 3)
58  return AVPROBE_SCORE_MAX;
59  return 0;
60 }
61 
62  static char *var_read_string(AVIOContext *pb, int size)
63 {
64  int n;
65  char *str;
66 
67  if (size < 0 || size == INT_MAX)
68  return NULL;
69 
70  str = av_malloc(size + 1);
71  if (!str)
72  return NULL;
73  n = avio_get_str(pb, size, str, size + 1);
74  if (n < size)
75  avio_skip(pb, size - n);
76  return str;
77 }
78 
79  static int var_read_int(AVIOContext *pb, int size)
80 {
81  int v;
82  char *s = var_read_string(pb, size);
83  if (!s)
84  return 0;
85  v = strtol(s, NULL, 10);
86  av_free(s);
87  return v;
88 }
89 
90  static AVRational var_read_float(AVIOContext *pb, int size)
91 {
92  AVRational v;
93  char *s = var_read_string(pb, size);
94  if (!s)
95  return (AVRational) { 0, 0 };
96  v = av_d2q(av_strtod(s, NULL), INT_MAX);
97  av_free(s);
98  return v;
99 }
100 
101  static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
102 {
103  char *value = var_read_string(avctx->pb, size);
104  if (value)
105  av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
106 }
107 
108  static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
109 {
110  if (channels <= 0) {
111  av_log(avctx, AV_LOG_ERROR, "Channel count %d invalid.\n", channels);
112  return AVERROR_INVALIDDATA;
113  }
114  av_channel_layout_default(&st->codecpar->ch_layout, channels);
115  return 0;
116 }
117 
118 /**
119  * Parse global variable
120  * @return < 0 if unknown
121  */
122  static int parse_global_var(AVFormatContext *avctx, AVStream *st,
123  const char *name, int size)
124 {
125  MvContext *mv = avctx->priv_data;
126  AVIOContext *pb = avctx->pb;
127  if (!strcmp(name, "__NUM_I_TRACKS")) {
128  mv->nb_video_tracks = var_read_int(pb, size);
129  } else if (!strcmp(name, "__NUM_A_TRACKS")) {
130  mv->nb_audio_tracks = var_read_int(pb, size);
131  } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
132  var_read_metadata(avctx, name, size);
133  } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") ||
134  !strcmp(name, "OPTIMIZED")) {
135  avio_skip(pb, size); // ignore
136  } else
137  return AVERROR_INVALIDDATA;
138 
139  return 0;
140 }
141 
142 /**
143  * Parse audio variable
144  * @return < 0 if unknown
145  */
146  static int parse_audio_var(AVFormatContext *avctx, AVStream *st,
147  const char *name, int size)
148 {
149  MvContext *mv = avctx->priv_data;
150  AVIOContext *pb = avctx->pb;
151  if (!strcmp(name, "__DIR_COUNT")) {
152  st->nb_frames = var_read_int(pb, size);
153  } else if (!strcmp(name, "AUDIO_FORMAT")) {
154  mv->aformat = var_read_int(pb, size);
155  } else if (!strcmp(name, "COMPRESSION")) {
156  mv->acompression = var_read_int(pb, size);
157  } else if (!strcmp(name, "DEFAULT_VOL")) {
158  var_read_metadata(avctx, name, size);
159  } else if (!strcmp(name, "NUM_CHANNELS")) {
160  return set_channels(avctx, st, var_read_int(pb, size));
161  } else if (!strcmp(name, "SAMPLE_RATE")) {
162  int sample_rate = var_read_int(pb, size);
163  if (sample_rate <= 0)
164  return AVERROR_INVALIDDATA;
165  st->codecpar->sample_rate = sample_rate;
166  avpriv_set_pts_info(st, 33, 1, st->codecpar->sample_rate);
167  } else if (!strcmp(name, "SAMPLE_WIDTH")) {
168  uint64_t bpc = var_read_int(pb, size) * (uint64_t)8;
169  if (bpc > 16)
170  return AVERROR_INVALIDDATA;
171  st->codecpar->bits_per_coded_sample = bpc;
172  } else
173  return AVERROR_INVALIDDATA;
174 
175  return 0;
176 }
177 
178 /**
179  * Parse video variable
180  * @return < 0 if unknown
181  */
182  static int parse_video_var(AVFormatContext *avctx, AVStream *st,
183  const char *name, int size)
184 {
185  AVIOContext *pb = avctx->pb;
186  if (!strcmp(name, "__DIR_COUNT")) {
187  st->nb_frames = st->duration = var_read_int(pb, size);
188  } else if (!strcmp(name, "COMPRESSION")) {
189  char *str = var_read_string(pb, size);
190  if (!str)
191  return AVERROR_INVALIDDATA;
192  if (!strcmp(str, "1")) {
193  st->codecpar->codec_id = AV_CODEC_ID_MVC1;
194  } else if (!strcmp(str, "2")) {
195  st->codecpar->format = AV_PIX_FMT_ABGR;
196  st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
197  } else if (!strcmp(str, "3")) {
198  st->codecpar->codec_id = AV_CODEC_ID_SGIRLE;
199  } else if (!strcmp(str, "10")) {
200  st->codecpar->codec_id = AV_CODEC_ID_MJPEG;
201  } else if (!strcmp(str, "MVC2")) {
202  st->codecpar->codec_id = AV_CODEC_ID_MVC2;
203  } else {
204  avpriv_request_sample(avctx, "Video compression %s", str);
205  }
206  av_free(str);
207  } else if (!strcmp(name, "FPS")) {
208  AVRational fps = var_read_float(pb, size);
209  avpriv_set_pts_info(st, 64, fps.den, fps.num);
210  st->avg_frame_rate = fps;
211  } else if (!strcmp(name, "HEIGHT")) {
212  st->codecpar->height = var_read_int(pb, size);
213  } else if (!strcmp(name, "PIXEL_ASPECT")) {
214  st->sample_aspect_ratio = var_read_float(pb, size);
215  av_reduce(&st->sample_aspect_ratio.num, &st->sample_aspect_ratio.den,
216  st->sample_aspect_ratio.num, st->sample_aspect_ratio.den,
217  INT_MAX);
218  } else if (!strcmp(name, "WIDTH")) {
219  st->codecpar->width = var_read_int(pb, size);
220  } else if (!strcmp(name, "ORIENTATION")) {
221  if (var_read_int(pb, size) == 1101) {
222  if (!st->codecpar->extradata) {
223  st->codecpar->extradata = av_strdup("BottomUp");
224  if (!st->codecpar->extradata)
225  return AVERROR(ENOMEM);
226  st->codecpar->extradata_size = 9;
227  }
228  }
229  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
230  var_read_metadata(avctx, name, size);
231  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
232  avio_skip(pb, size); // ignore
233  } else
234  return AVERROR_INVALIDDATA;
235 
236  return 0;
237 }
238 
239  static int read_table(AVFormatContext *avctx, AVStream *st,
240  int (*parse)(AVFormatContext *avctx, AVStream *st,
241  const char *name, int size))
242 {
243  unsigned count;
244  int i;
245 
246  AVIOContext *pb = avctx->pb;
247  avio_skip(pb, 4);
248  count = avio_rb32(pb);
249  avio_skip(pb, 4);
250  for (i = 0; i < count; i++) {
251  char name[17];
252  int size;
253 
254  if (avio_feof(pb))
255  return AVERROR_EOF;
256 
257  avio_read(pb, name, 16);
258  name[sizeof(name) - 1] = 0;
259  size = avio_rb32(pb);
260  if (size < 0) {
261  av_log(avctx, AV_LOG_ERROR, "entry size %d is invalid\n", size);
262  return AVERROR_INVALIDDATA;
263  }
264  if (parse(avctx, st, name, size) < 0) {
265  avpriv_request_sample(avctx, "Variable %s", name);
266  avio_skip(pb, size);
267  }
268  }
269  return 0;
270 }
271 
272  static void read_index(AVIOContext *pb, AVStream *st)
273 {
274  uint64_t timestamp = 0;
275  int i;
276  for (i = 0; i < st->nb_frames; i++) {
277  uint32_t pos = avio_rb32(pb);
278  uint32_t size = avio_rb32(pb);
279  avio_skip(pb, 8);
280  if (avio_feof(pb))
281  return ;
282  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
283  if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
284  timestamp += size / (st->codecpar->ch_layout.nb_channels * 2LL);
285  } else {
286  timestamp++;
287  }
288  }
289 }
290 
291  static int mv_read_header(AVFormatContext *avctx)
292 {
293  MvContext *mv = avctx->priv_data;
294  AVIOContext *pb = avctx->pb;
295  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
296  int version, i;
297  int ret;
298 
299  avio_skip(pb, 4);
300 
301  version = avio_rb16(pb);
302  if (version == 2) {
303  uint64_t timestamp;
304  int v;
305  uint32_t bytes_per_sample;
306  AVRational fps;
307 
308  avio_skip(pb, 10);
309 
310  fps = av_d2q(av_int2double(avio_rb64(pb)), INT_MAX);
311 
312  /* allocate audio track first to prevent unnecessary seeking
313  * (audio packet always precede video packet for a given frame) */
314  v = avio_rb16(pb);
315  if (v == MOVIE_SOUND) {
316  /* movie has sound so allocate an audio stream */
317  ast = avformat_new_stream(avctx, NULL);
318  if (!ast)
319  return AVERROR(ENOMEM);
320  } else if (v != MOVIE_SILENT)
321  return AVERROR_INVALIDDATA;
322 
323  avio_skip(pb, 2);
324 
325  vst = avformat_new_stream(avctx, NULL);
326  if (!vst)
327  return AVERROR(ENOMEM);
328  avpriv_set_pts_info(vst, 64, fps.den, fps.num);
329  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
330  vst->avg_frame_rate = fps;
331  vst->duration = vst->nb_frames = avio_rb32(pb);
332  v = avio_rb32(pb);
333  switch (v) {
334  case 1:
335  vst->codecpar->codec_id = AV_CODEC_ID_MVC1;
336  break;
337  case 2:
338  vst->codecpar->format = AV_PIX_FMT_ARGB;
339  vst->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
340  break;
341  default:
342  avpriv_request_sample(avctx, "Video compression %i", v);
343  break;
344  }
345  vst->codecpar->codec_tag = 0;
346  vst->codecpar->width = avio_rb32(pb);
347  vst->codecpar->height = avio_rb32(pb);
348  avio_skip(pb, 12);
349 
350  if (ast) {
351  ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
352  ast->nb_frames = vst->nb_frames;
353  ast->codecpar->sample_rate = avio_rb32(pb);
354  if (ast->codecpar->sample_rate <= 0) {
355  av_log(avctx, AV_LOG_ERROR, "Invalid sample rate %d\n", ast->codecpar->sample_rate);
356  return AVERROR_INVALIDDATA;
357  }
358  avpriv_set_pts_info(ast, 33, 1, ast->codecpar->sample_rate);
359 
360  bytes_per_sample = avio_rb32(pb);
361 
362  v = avio_rb32(pb);
363  if (v == AUDIO_FORMAT_SIGNED) {
364  switch (bytes_per_sample) {
365  case 1:
366  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S8;
367  break;
368  case 2:
369  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S16BE;
370  break;
371  default:
372  avpriv_request_sample(avctx, "Audio sample size %i bytes", bytes_per_sample);
373  break;
374  }
375  } else {
376  avpriv_request_sample(avctx, "Audio compression (format %i)", v);
377  }
378 
379  if (bytes_per_sample == 0)
380  return AVERROR_INVALIDDATA;
381 
382  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
383  return AVERROR_INVALIDDATA;
384 
385  avio_skip(pb, 8);
386  } else
387  avio_skip(pb, 24); /* skip meaningless audio metadata */
388 
389  var_read_metadata(avctx, "title", 0x80);
390  var_read_metadata(avctx, "comment", 0x100);
391  avio_skip(pb, 0x80);
392 
393  timestamp = 0;
394  for (i = 0; i < vst->nb_frames; i++) {
395  uint32_t pos = avio_rb32(pb);
396  uint32_t asize = avio_rb32(pb);
397  uint32_t vsize = avio_rb32(pb);
398  if (avio_feof(pb))
399  return AVERROR_INVALIDDATA;
400  avio_skip(pb, 8);
401  if (ast) {
402  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
403  timestamp += asize / (ast->codecpar->ch_layout.nb_channels * (uint64_t)bytes_per_sample);
404  }
405  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
406  }
407  } else if (!version && avio_rb16(pb) == 3) {
408  avio_skip(pb, 4);
409 
410  if ((ret = read_table(avctx, NULL, parse_global_var)) < 0)
411  return ret;
412 
413  if (mv->nb_audio_tracks < 0 || mv->nb_video_tracks < 0 ||
414  (mv->nb_audio_tracks == 0 && mv->nb_video_tracks == 0)) {
415  av_log(avctx, AV_LOG_ERROR, "Stream count is invalid.\n");
416  return AVERROR_INVALIDDATA;
417  }
418 
419  if (mv->nb_audio_tracks > 1) {
420  avpriv_request_sample(avctx, "Multiple audio streams support");
421  return AVERROR_PATCHWELCOME;
422  } else if (mv->nb_audio_tracks) {
423  ast = avformat_new_stream(avctx, NULL);
424  if (!ast)
425  return AVERROR(ENOMEM);
426  ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
427  if ((ret = read_table(avctx, ast, parse_audio_var)) < 0)
428  return ret;
429  if (mv->acompression == 100 &&
430  mv->aformat == AUDIO_FORMAT_SIGNED &&
431  ast->codecpar->bits_per_coded_sample == 16) {
432  ast->codecpar->codec_id = AV_CODEC_ID_PCM_S16BE;
433  } else {
434  avpriv_request_sample(avctx,
435  "Audio compression %i (format %i, sr %i)",
436  mv->acompression, mv->aformat,
437  ast->codecpar->bits_per_coded_sample);
438  ast->codecpar->codec_id = AV_CODEC_ID_NONE;
439  }
440  if (ast->codecpar->ch_layout.nb_channels <= 0) {
441  av_log(avctx, AV_LOG_ERROR, "No valid channel count found.\n");
442  return AVERROR_INVALIDDATA;
443  }
444  }
445 
446  if (mv->nb_video_tracks > 1) {
447  avpriv_request_sample(avctx, "Multiple video streams support");
448  return AVERROR_PATCHWELCOME;
449  } else if (mv->nb_video_tracks) {
450  vst = avformat_new_stream(avctx, NULL);
451  if (!vst)
452  return AVERROR(ENOMEM);
453  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
454  if ((ret = read_table(avctx, vst, parse_video_var))<0)
455  return ret;
456  }
457 
458  if (mv->nb_audio_tracks)
459  read_index(pb, ast);
460 
461  if (mv->nb_video_tracks)
462  read_index(pb, vst);
463  } else {
464  avpriv_request_sample(avctx, "Version %i", version);
465  return AVERROR_PATCHWELCOME;
466  }
467 
468  return 0;
469 }
470 
471  static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
472 {
473  MvContext *mv = avctx->priv_data;
474  AVIOContext *pb = avctx->pb;
475  AVStream *st = avctx->streams[mv->stream_index];
476  FFStream *const sti = ffstream(st);
477  const AVIndexEntry *index;
478  int frame = mv->frame[mv->stream_index];
479  int64_t ret;
480  uint64_t pos;
481 
482  if (frame < sti->nb_index_entries) {
483  index = &sti->index_entries[frame];
484  pos = avio_tell(pb);
485  if (index->pos > pos)
486  avio_skip(pb, index->pos - pos);
487  else if (index->pos < pos) {
488  if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
489  return AVERROR(EIO);
490  ret = avio_seek(pb, index->pos, SEEK_SET);
491  if (ret < 0)
492  return ret;
493  }
494  ret = av_get_packet(pb, pkt, index->size);
495  if (ret < 0)
496  return ret;
497 
498  pkt->stream_index = mv->stream_index;
499  pkt->pts = index->timestamp;
500  pkt->flags |= AV_PKT_FLAG_KEY;
501 
502  mv->frame[mv->stream_index]++;
503  mv->eof_count = 0;
504  } else {
505  mv->eof_count++;
506  if (mv->eof_count >= avctx->nb_streams)
507  return AVERROR_EOF;
508 
509  // avoid returning 0 without a packet
510  return AVERROR(EAGAIN);
511  }
512 
513  mv->stream_index++;
514  if (mv->stream_index >= avctx->nb_streams)
515  mv->stream_index = 0;
516 
517  return 0;
518 }
519 
520  static int mv_read_seek(AVFormatContext *avctx, int stream_index,
521  int64_t timestamp, int flags)
522 {
523  MvContext *mv = avctx->priv_data;
524  AVStream *st = avctx->streams[stream_index];
525  int frame, i;
526 
527  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
528  return AVERROR(ENOSYS);
529 
530  if (!(avctx->pb->seekable & AVIO_SEEKABLE_NORMAL))
531  return AVERROR(EIO);
532 
533  frame = av_index_search_timestamp(st, timestamp, flags);
534  if (frame < 0)
535  return AVERROR_INVALIDDATA;
536 
537  for (i = 0; i < avctx->nb_streams; i++)
538  mv->frame[i] = frame;
539  return 0;
540 }
541 
542  const AVInputFormat ff_mv_demuxer = {
543  .name = "mv",
544  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
545  .priv_data_size = sizeof(MvContext),
546  .read_probe = mv_probe,
547  .read_header = mv_read_header,
548  .read_packet = mv_read_packet,
549  .read_seek = mv_read_seek,
550 };
MvContext::nb_video_tracks
int nb_video_tracks
Definition: mvdec.c:37
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:76
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:40
MvContext::frame
int frame[2]
frame nb for current stream
Definition: mvdec.c:42
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:243
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AVSEEK_FLAG_FRAME
#define AVSEEK_FLAG_FRAME
seeking based on frame number
Definition: avformat.h:2197
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:62
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:108
rational.h
mv
static const int8_t mv[256][2]
Definition: 4xm.c:80
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:237
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1172
parse
static int parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: vp3_parser.c:23
AVStream::avg_frame_rate
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:927
AVSEEK_FLAG_BYTE
#define AVSEEK_FLAG_BYTE
seeking based on position in bytes
Definition: avformat.h:2195
MOVIE_SILENT
#define MOVIE_SILENT
Definition: mvdec.c:50
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
intfloat.h
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
AVIndexEntry
Definition: avformat.h:697
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:705
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:264
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:771
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
AV_CODEC_ID_PCM_S16BE
@ AV_CODEC_ID_PCM_S16BE
Definition: codec_id.h:327
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:120
AUDIO_FORMAT_SIGNED
#define AUDIO_FORMAT_SIGNED
Definition: mvdec.c:52
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:500
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:897
var_read_int
static int var_read_int(AVIOContext *pb, int size)
Definition: mvdec.c:79
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:330
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:782
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
AVFormatContext::metadata
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1330
AVInputFormat
Definition: avformat.h:546
MvContext::aformat
int aformat
audio format
Definition: mvdec.c:45
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
channels
channels
Definition: aptx.h:31
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
parse_audio_var
static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse audio variable.
Definition: mvdec.c:146
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:101
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:471
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:929
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1146
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:182
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
parse_global_var
static int parse_global_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse global variable.
Definition: mvdec.c:122
AV_PIX_FMT_ABGR
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:94
MvContext::stream_index
int stream_index
current stream index
Definition: mvdec.c:41
index
int index
Definition: gxfenc.c:89
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:899
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:80
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1160
MOVIE_SOUND
#define MOVIE_SOUND
Definition: mvdec.c:49
eval.h
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
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:115
AVIOContext::seekable
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:267
FFStream
Definition: internal.h:196
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:887
size
int size
Definition: twinvq_data.h:10344
ff_mv_demuxer
const AVInputFormat ff_mv_demuxer
Definition: mvdec.c:542
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:916
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
mv_probe
static int mv_probe(const AVProbeData *p)
Definition: mvdec.c:54
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:92
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:962
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:520
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:269
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
AVCodecParameters::height
int height
Definition: codec_par.h:129
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
MvContext
Definition: mvdec.c:36
AV_CODEC_ID_MVC1
@ AV_CODEC_ID_MVC1
Definition: codec_id.h:236
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:102
read_index
static void read_index(AVIOContext *pb, AVStream *st)
Definition: mvdec.c:272
tag
uint32_t tag
Definition: movenc.c:1641
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:252
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:264
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:106
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:767
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
mv_read_header
static int mv_read_header(AVFormatContext *avctx)
Definition: mvdec.c:291
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:633
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:251
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:270
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
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:104
MvContext::nb_audio_tracks
int nb_audio_tracks
Definition: mvdec.c:38
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecParameters::format
int format
Definition: codec_par.h:86
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
MvContext::acompression
int acompression
compression level for audio stream
Definition: mvdec.c:44
AV_CODEC_ID_SGIRLE
@ AV_CODEC_ID_SGIRLE
Definition: codec_id.h:235
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
read_table
static int read_table(AVFormatContext *avctx, AVStream *st, int(*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
Definition: mvdec.c:239
convert_header.str
string str
Definition: convert_header.py:20
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
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:90
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1132
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:240
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:367
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