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 
28 #include "libavutil/eval.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/rational.h"
31 
32 #include "avformat.h"
33 #include "internal.h"
34 
35 typedef struct MvContext {
38 
39  int eof_count; ///< number of streams that have finished
40  int stream_index; ///< current stream index
41  int frame[2]; ///< frame nb for current stream
42 
43  int acompression; ///< compression level for audio stream
44  int aformat; ///< audio format
45 } MvContext;
46 
47 #define AUDIO_FORMAT_SIGNED 401
48 
49 static int mv_probe(const AVProbeData *p)
50 {
51  if (AV_RB32(p->buf) == MKBETAG('M', 'O', 'V', 'I') &&
52  AV_RB16(p->buf + 4) < 3)
53  return AVPROBE_SCORE_MAX;
54  return 0;
55 }
56 
57 static char *var_read_string(AVIOContext *pb, int size)
58 {
59  int n;
60  char *str;
61 
62  if (size < 0 || size == INT_MAX)
63  return NULL;
64 
65  str = av_malloc(size + 1);
66  if (!str)
67  return NULL;
68  n = avio_get_str(pb, size, str, size + 1);
69  if (n < size)
70  avio_skip(pb, size - n);
71  return str;
72 }
73 
74 static int var_read_int(AVIOContext *pb, int size)
75 {
76  int v;
77  char *s = var_read_string(pb, size);
78  if (!s)
79  return 0;
80  v = strtol(s, NULL, 10);
81  av_free(s);
82  return v;
83 }
84 
86 {
87  AVRational v;
88  char *s = var_read_string(pb, size);
89  if (!s)
90  return (AVRational) { 0, 0 };
91  v = av_d2q(av_strtod(s, NULL), INT_MAX);
92  av_free(s);
93  return v;
94 }
95 
96 static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
97 {
98  char *value = var_read_string(avctx->pb, size);
99  if (value)
100  av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
101 }
102 
103 static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
104 {
105  if (channels <= 0) {
106  av_log(avctx, AV_LOG_ERROR, "Channel count %d invalid.\n", channels);
107  return AVERROR_INVALIDDATA;
108  }
109  st->codecpar->channels = channels;
112  return 0;
113 }
114 
115 /**
116  * Parse global variable
117  * @return < 0 if unknown
118  */
120  const char *name, int size)
121 {
122  MvContext *mv = avctx->priv_data;
123  AVIOContext *pb = avctx->pb;
124  if (!strcmp(name, "__NUM_I_TRACKS")) {
125  mv->nb_video_tracks = var_read_int(pb, size);
126  } else if (!strcmp(name, "__NUM_A_TRACKS")) {
127  mv->nb_audio_tracks = var_read_int(pb, size);
128  } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
129  var_read_metadata(avctx, name, size);
130  } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") ||
131  !strcmp(name, "OPTIMIZED")) {
132  avio_skip(pb, size); // ignore
133  } else
134  return AVERROR_INVALIDDATA;
135 
136  return 0;
137 }
138 
139 /**
140  * Parse audio variable
141  * @return < 0 if unknown
142  */
143 static int parse_audio_var(AVFormatContext *avctx, AVStream *st,
144  const char *name, int size)
145 {
146  MvContext *mv = avctx->priv_data;
147  AVIOContext *pb = avctx->pb;
148  if (!strcmp(name, "__DIR_COUNT")) {
149  st->nb_frames = var_read_int(pb, size);
150  } else if (!strcmp(name, "AUDIO_FORMAT")) {
151  mv->aformat = var_read_int(pb, size);
152  } else if (!strcmp(name, "COMPRESSION")) {
153  mv->acompression = var_read_int(pb, size);
154  } else if (!strcmp(name, "DEFAULT_VOL")) {
155  var_read_metadata(avctx, name, size);
156  } else if (!strcmp(name, "NUM_CHANNELS")) {
157  return set_channels(avctx, st, var_read_int(pb, size));
158  } else if (!strcmp(name, "SAMPLE_RATE")) {
159  st->codecpar->sample_rate = var_read_int(pb, size);
160  avpriv_set_pts_info(st, 33, 1, st->codecpar->sample_rate);
161  } else if (!strcmp(name, "SAMPLE_WIDTH")) {
162  uint64_t bpc = var_read_int(pb, size) * (uint64_t)8;
163  if (bpc > 16)
164  return AVERROR_INVALIDDATA;
165  st->codecpar->bits_per_coded_sample = bpc;
166  } else
167  return AVERROR_INVALIDDATA;
168 
169  return 0;
170 }
171 
172 /**
173  * Parse video variable
174  * @return < 0 if unknown
175  */
176 static int parse_video_var(AVFormatContext *avctx, AVStream *st,
177  const char *name, int size)
178 {
179  AVIOContext *pb = avctx->pb;
180  if (!strcmp(name, "__DIR_COUNT")) {
181  st->nb_frames = st->duration = var_read_int(pb, size);
182  } else if (!strcmp(name, "COMPRESSION")) {
183  char *str = var_read_string(pb, size);
184  if (!str)
185  return AVERROR_INVALIDDATA;
186  if (!strcmp(str, "1")) {
188  } else if (!strcmp(str, "2")) {
191  } else if (!strcmp(str, "3")) {
193  } else if (!strcmp(str, "10")) {
195  } else if (!strcmp(str, "MVC2")) {
197  } else {
198  avpriv_request_sample(avctx, "Video compression %s", str);
199  }
200  av_free(str);
201  } else if (!strcmp(name, "FPS")) {
202  AVRational fps = var_read_float(pb, size);
203  avpriv_set_pts_info(st, 64, fps.den, fps.num);
204  st->avg_frame_rate = fps;
205  } else if (!strcmp(name, "HEIGHT")) {
206  st->codecpar->height = var_read_int(pb, size);
207  } else if (!strcmp(name, "PIXEL_ASPECT")) {
208  st->sample_aspect_ratio = var_read_float(pb, size);
211  INT_MAX);
212  } else if (!strcmp(name, "WIDTH")) {
213  st->codecpar->width = var_read_int(pb, size);
214  } else if (!strcmp(name, "ORIENTATION")) {
215  if (var_read_int(pb, size) == 1101) {
216  if (!st->codecpar->extradata) {
217  st->codecpar->extradata = av_strdup("BottomUp");
218  if (!st->codecpar->extradata)
219  return AVERROR(ENOMEM);
220  st->codecpar->extradata_size = 9;
221  }
222  }
223  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
224  var_read_metadata(avctx, name, size);
225  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
226  avio_skip(pb, size); // ignore
227  } else
228  return AVERROR_INVALIDDATA;
229 
230  return 0;
231 }
232 
233 static int read_table(AVFormatContext *avctx, AVStream *st,
234  int (*parse)(AVFormatContext *avctx, AVStream *st,
235  const char *name, int size))
236 {
237  unsigned count;
238  int i;
239 
240  AVIOContext *pb = avctx->pb;
241  avio_skip(pb, 4);
242  count = avio_rb32(pb);
243  avio_skip(pb, 4);
244  for (i = 0; i < count; i++) {
245  char name[17];
246  int size;
247 
248  if (avio_feof(pb))
249  return AVERROR_EOF;
250 
251  avio_read(pb, name, 16);
252  name[sizeof(name) - 1] = 0;
253  size = avio_rb32(pb);
254  if (size < 0) {
255  av_log(avctx, AV_LOG_ERROR, "entry size %d is invalid\n", size);
256  return AVERROR_INVALIDDATA;
257  }
258  if (parse(avctx, st, name, size) < 0) {
259  avpriv_request_sample(avctx, "Variable %s", name);
260  avio_skip(pb, size);
261  }
262  }
263  return 0;
264 }
265 
266 static void read_index(AVIOContext *pb, AVStream *st)
267 {
268  uint64_t timestamp = 0;
269  int i;
270  for (i = 0; i < st->nb_frames; i++) {
271  uint32_t pos = avio_rb32(pb);
272  uint32_t size = avio_rb32(pb);
273  avio_skip(pb, 8);
274  if (avio_feof(pb))
275  return ;
276  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
277  if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
278  timestamp += size / (st->codecpar->channels * 2LL);
279  } else {
280  timestamp++;
281  }
282  }
283 }
284 
285 static int mv_read_header(AVFormatContext *avctx)
286 {
287  MvContext *mv = avctx->priv_data;
288  AVIOContext *pb = avctx->pb;
289  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
290  int version, i;
291  int ret;
292 
293  avio_skip(pb, 4);
294 
295  version = avio_rb16(pb);
296  if (version == 2) {
297  uint64_t timestamp;
298  int v;
299  avio_skip(pb, 22);
300 
301  /* allocate audio track first to prevent unnecessary seeking
302  * (audio packet always precede video packet for a given frame) */
303  ast = avformat_new_stream(avctx, NULL);
304  if (!ast)
305  return AVERROR(ENOMEM);
306 
307  vst = avformat_new_stream(avctx, NULL);
308  if (!vst)
309  return AVERROR(ENOMEM);
310  avpriv_set_pts_info(vst, 64, 1, 15);
311  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
312  vst->avg_frame_rate = av_inv_q(vst->time_base);
313  vst->nb_frames = avio_rb32(pb);
314  v = avio_rb32(pb);
315  switch (v) {
316  case 1:
317  vst->codecpar->codec_id = AV_CODEC_ID_MVC1;
318  break;
319  case 2:
320  vst->codecpar->format = AV_PIX_FMT_ARGB;
321  vst->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
322  break;
323  default:
324  avpriv_request_sample(avctx, "Video compression %i", v);
325  break;
326  }
327  vst->codecpar->codec_tag = 0;
328  vst->codecpar->width = avio_rb32(pb);
329  vst->codecpar->height = avio_rb32(pb);
330  avio_skip(pb, 12);
331 
333  ast->nb_frames = vst->nb_frames;
334  ast->codecpar->sample_rate = avio_rb32(pb);
335  if (ast->codecpar->sample_rate <= 0) {
336  av_log(avctx, AV_LOG_ERROR, "Invalid sample rate %d\n", ast->codecpar->sample_rate);
337  return AVERROR_INVALIDDATA;
338  }
339  avpriv_set_pts_info(ast, 33, 1, ast->codecpar->sample_rate);
340  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
341  return AVERROR_INVALIDDATA;
342 
343  v = avio_rb32(pb);
344  if (v == AUDIO_FORMAT_SIGNED) {
346  } else {
347  avpriv_request_sample(avctx, "Audio compression (format %i)", v);
348  }
349 
350  avio_skip(pb, 12);
351  var_read_metadata(avctx, "title", 0x80);
352  var_read_metadata(avctx, "comment", 0x100);
353  avio_skip(pb, 0x80);
354 
355  timestamp = 0;
356  for (i = 0; i < vst->nb_frames; i++) {
357  uint32_t pos = avio_rb32(pb);
358  uint32_t asize = avio_rb32(pb);
359  uint32_t vsize = avio_rb32(pb);
360  if (avio_feof(pb))
361  return AVERROR_INVALIDDATA;
362  avio_skip(pb, 8);
363  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
364  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
365  timestamp += asize / (ast->codecpar->channels * 2LL);
366  }
367  } else if (!version && avio_rb16(pb) == 3) {
368  avio_skip(pb, 4);
369 
370  if ((ret = read_table(avctx, NULL, parse_global_var)) < 0)
371  return ret;
372 
373  if (mv->nb_audio_tracks < 0 || mv->nb_video_tracks < 0 ||
374  (mv->nb_audio_tracks == 0 && mv->nb_video_tracks == 0)) {
375  av_log(avctx, AV_LOG_ERROR, "Stream count is invalid.\n");
376  return AVERROR_INVALIDDATA;
377  }
378 
379  if (mv->nb_audio_tracks > 1) {
380  avpriv_request_sample(avctx, "Multiple audio streams support");
381  return AVERROR_PATCHWELCOME;
382  } else if (mv->nb_audio_tracks) {
383  ast = avformat_new_stream(avctx, NULL);
384  if (!ast)
385  return AVERROR(ENOMEM);
387  if ((read_table(avctx, ast, parse_audio_var)) < 0)
388  return ret;
389  if (mv->acompression == 100 &&
390  mv->aformat == AUDIO_FORMAT_SIGNED &&
391  ast->codecpar->bits_per_coded_sample == 16) {
393  } else {
394  avpriv_request_sample(avctx,
395  "Audio compression %i (format %i, sr %i)",
396  mv->acompression, mv->aformat,
399  }
400  if (ast->codecpar->channels <= 0) {
401  av_log(avctx, AV_LOG_ERROR, "No valid channel count found.\n");
402  return AVERROR_INVALIDDATA;
403  }
404  }
405 
406  if (mv->nb_video_tracks > 1) {
407  avpriv_request_sample(avctx, "Multiple video streams support");
408  return AVERROR_PATCHWELCOME;
409  } else if (mv->nb_video_tracks) {
410  vst = avformat_new_stream(avctx, NULL);
411  if (!vst)
412  return AVERROR(ENOMEM);
413  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
414  if ((ret = read_table(avctx, vst, parse_video_var))<0)
415  return ret;
416  }
417 
418  if (mv->nb_audio_tracks)
419  read_index(pb, ast);
420 
421  if (mv->nb_video_tracks)
422  read_index(pb, vst);
423  } else {
424  avpriv_request_sample(avctx, "Version %i", version);
425  return AVERROR_PATCHWELCOME;
426  }
427 
428  return 0;
429 }
430 
432 {
433  MvContext *mv = avctx->priv_data;
434  AVIOContext *pb = avctx->pb;
435  AVStream *st = avctx->streams[mv->stream_index];
436  const AVIndexEntry *index;
437  int frame = mv->frame[mv->stream_index];
438  int64_t ret;
439  uint64_t pos;
440 
441  if (frame < st->internal->nb_index_entries) {
442  index = &st->internal->index_entries[frame];
443  pos = avio_tell(pb);
444  if (index->pos > pos)
445  avio_skip(pb, index->pos - pos);
446  else if (index->pos < pos) {
447  if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
448  return AVERROR(EIO);
449  ret = avio_seek(pb, index->pos, SEEK_SET);
450  if (ret < 0)
451  return ret;
452  }
453  ret = av_get_packet(pb, pkt, index->size);
454  if (ret < 0)
455  return ret;
456 
457  pkt->stream_index = mv->stream_index;
458  pkt->pts = index->timestamp;
459  pkt->flags |= AV_PKT_FLAG_KEY;
460 
461  mv->frame[mv->stream_index]++;
462  mv->eof_count = 0;
463  } else {
464  mv->eof_count++;
465  if (mv->eof_count >= avctx->nb_streams)
466  return AVERROR_EOF;
467 
468  // avoid returning 0 without a packet
469  return AVERROR(EAGAIN);
470  }
471 
472  mv->stream_index++;
473  if (mv->stream_index >= avctx->nb_streams)
474  mv->stream_index = 0;
475 
476  return 0;
477 }
478 
480  int64_t timestamp, int flags)
481 {
482  MvContext *mv = avctx->priv_data;
483  AVStream *st = avctx->streams[stream_index];
484  int frame, i;
485 
486  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
487  return AVERROR(ENOSYS);
488 
489  if (!(avctx->pb->seekable & AVIO_SEEKABLE_NORMAL))
490  return AVERROR(EIO);
491 
492  frame = av_index_search_timestamp(st, timestamp, flags);
493  if (frame < 0)
494  return AVERROR_INVALIDDATA;
495 
496  for (i = 0; i < avctx->nb_streams; i++)
497  mv->frame[i] = frame;
498  return 0;
499 }
500 
502  .name = "mv",
503  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
504  .priv_data_size = sizeof(MvContext),
505  .read_probe = mv_probe,
509 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
version
Definition: libkvazaar.c:320
static int mv_read_header(AVFormatContext *avctx)
Definition: mvdec.c:285
static int parse_video_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse video variable.
Definition: mvdec.c:176
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:2044
static char * var_read_string(AVIOContext *pb, int size)
Definition: mvdec.c:57
int stream_index
current stream index
Definition: mvdec.c:40
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:4999
int64_t pos
Definition: avformat.h:813
#define avpriv_request_sample(...)
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:946
int num
Numerator.
Definition: rational.h:59
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
static AVRational var_read_float(AVIOContext *pb, int size)
Definition: mvdec.c:85
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
#define AV_CH_LAYOUT_STEREO
AVPacket * pkt
Definition: movenc.c:59
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
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:91
fg index
static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: mvdec.c:431
Format I/O context.
Definition: avformat.h:1247
static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
Definition: mvdec.c:96
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
#define av_malloc(s)
int width
Video only.
Definition: codec_par.h:126
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4553
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:91
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1315
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:94
uint32_t tag
Definition: movenc.c:1611
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
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
channels
Definition: aptx.h:33
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
#define AVINDEX_KEYFRAME
Definition: avformat.h:820
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1489
int eof_count
number of streams that have finished
Definition: mvdec.c:39
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2161
static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t timestamp, int flags)
Definition: mvdec.c:479
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:814
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
unsigned int pos
Definition: spdifenc.c:412
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int nb_audio_tracks
Definition: mvdec.c:37
GLsizei count
Definition: opengl_enc.c:108
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:957
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:92
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
static int read_table(AVFormatContext *avctx, AVStream *st, int(*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
Definition: mvdec.c:233
static void read_index(AVIOContext *pb, AVStream *st)
Definition: mvdec.c:266
int frame[2]
frame nb for current stream
Definition: mvdec.c:41
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:250
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1303
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
audio channel layout utility functions
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that&#39;s been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:76
#define AUDIO_FORMAT_SIGNED
Definition: mvdec.c:47
static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse audio variable.
Definition: mvdec.c:143
int nb_video_tracks
Definition: mvdec.c:36
#define s(width, name)
Definition: cbs_vp9.c:257
int acompression
compression level for audio stream
Definition: mvdec.c:43
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
Stream structure.
Definition: avformat.h:884
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
double av_strtod(const char *numstr, char **tail)
Parse the string in numstr and return its value as a double.
Definition: eval.c:106
static const int8_t mv[256][2]
Definition: 4xm.c:78
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:253
AVStreamInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1123
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
static int mv_probe(const AVProbeData *p)
Definition: mvdec.c:49
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define AVSEEK_FLAG_BYTE
seeking based on position in bytes
Definition: avformat.h:2431
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
AVInputFormat ff_mv_demuxer
Definition: mvdec.c:501
static int var_read_int(AVIOContext *pb, int size)
Definition: mvdec.c:74
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int parse_global_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
Parse global variable.
Definition: mvdec.c:119
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVRational av_d2q(double d, int max)
Convert a double precision floating point number to a rational.
Definition: rational.c:106
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:933
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
int sample_rate
Audio only.
Definition: codec_par.h:170
int aformat
audio format
Definition: mvdec.c:44
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
Main libavformat public API header.
Utilties for rational number calculation.
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:935
int den
Denominator.
Definition: rational.h:60
#define MKBETAG(a, b, c, d)
Definition: common.h:479
#define av_free(p)
void * priv_data
Format private data.
Definition: avformat.h:1275
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
#define AVSEEK_FLAG_FRAME
seeking based on frame number
Definition: avformat.h:2433
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
int channels
Audio only.
Definition: codec_par.h:166
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
static int set_channels(AVFormatContext *avctx, AVStream *st, int channels)
Definition: mvdec.c:103
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:860
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
int stream_index
Definition: packet.h:371
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
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: packet.h:346
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
int i
Definition: input.c:407
simple arithmetic expression evaluator
const char * name
Definition: opengl_enc.c:102