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  st->codecpar->extradata = av_strdup("BottomUp");
217  if (!st->codecpar->extradata)
218  return AVERROR(ENOMEM);
219  st->codecpar->extradata_size = 9;
220  }
221  } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
222  var_read_metadata(avctx, name, size);
223  } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
224  avio_skip(pb, size); // ignore
225  } else
226  return AVERROR_INVALIDDATA;
227 
228  return 0;
229 }
230 
231 static int read_table(AVFormatContext *avctx, AVStream *st,
232  int (*parse)(AVFormatContext *avctx, AVStream *st,
233  const char *name, int size))
234 {
235  unsigned count;
236  int i;
237 
238  AVIOContext *pb = avctx->pb;
239  avio_skip(pb, 4);
240  count = avio_rb32(pb);
241  avio_skip(pb, 4);
242  for (i = 0; i < count; i++) {
243  char name[17];
244  int size;
245 
246  if (avio_feof(pb))
247  return AVERROR_EOF;
248 
249  avio_read(pb, name, 16);
250  name[sizeof(name) - 1] = 0;
251  size = avio_rb32(pb);
252  if (size < 0) {
253  av_log(avctx, AV_LOG_ERROR, "entry size %d is invalid\n", size);
254  return AVERROR_INVALIDDATA;
255  }
256  if (parse(avctx, st, name, size) < 0) {
257  avpriv_request_sample(avctx, "Variable %s", name);
258  avio_skip(pb, size);
259  }
260  }
261  return 0;
262 }
263 
264 static void read_index(AVIOContext *pb, AVStream *st)
265 {
266  uint64_t timestamp = 0;
267  int i;
268  for (i = 0; i < st->nb_frames; i++) {
269  uint32_t pos = avio_rb32(pb);
270  uint32_t size = avio_rb32(pb);
271  avio_skip(pb, 8);
272  if (avio_feof(pb))
273  return ;
274  av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
275  if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
276  timestamp += size / (st->codecpar->channels * 2LL);
277  } else {
278  timestamp++;
279  }
280  }
281 }
282 
283 static int mv_read_header(AVFormatContext *avctx)
284 {
285  MvContext *mv = avctx->priv_data;
286  AVIOContext *pb = avctx->pb;
287  AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning
288  int version, i;
289  int ret;
290 
291  avio_skip(pb, 4);
292 
293  version = avio_rb16(pb);
294  if (version == 2) {
295  uint64_t timestamp;
296  int v;
297  avio_skip(pb, 22);
298 
299  /* allocate audio track first to prevent unnecessary seeking
300  * (audio packet always precede video packet for a given frame) */
301  ast = avformat_new_stream(avctx, NULL);
302  if (!ast)
303  return AVERROR(ENOMEM);
304 
305  vst = avformat_new_stream(avctx, NULL);
306  if (!vst)
307  return AVERROR(ENOMEM);
308  avpriv_set_pts_info(vst, 64, 1, 15);
309  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
310  vst->avg_frame_rate = av_inv_q(vst->time_base);
311  vst->nb_frames = avio_rb32(pb);
312  v = avio_rb32(pb);
313  switch (v) {
314  case 1:
315  vst->codecpar->codec_id = AV_CODEC_ID_MVC1;
316  break;
317  case 2:
318  vst->codecpar->format = AV_PIX_FMT_ARGB;
319  vst->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
320  break;
321  default:
322  avpriv_request_sample(avctx, "Video compression %i", v);
323  break;
324  }
325  vst->codecpar->codec_tag = 0;
326  vst->codecpar->width = avio_rb32(pb);
327  vst->codecpar->height = avio_rb32(pb);
328  avio_skip(pb, 12);
329 
331  ast->nb_frames = vst->nb_frames;
332  ast->codecpar->sample_rate = avio_rb32(pb);
333  if (ast->codecpar->sample_rate <= 0) {
334  av_log(avctx, AV_LOG_ERROR, "Invalid sample rate %d\n", ast->codecpar->sample_rate);
335  return AVERROR_INVALIDDATA;
336  }
337  avpriv_set_pts_info(ast, 33, 1, ast->codecpar->sample_rate);
338  if (set_channels(avctx, ast, avio_rb32(pb)) < 0)
339  return AVERROR_INVALIDDATA;
340 
341  v = avio_rb32(pb);
342  if (v == AUDIO_FORMAT_SIGNED) {
344  } else {
345  avpriv_request_sample(avctx, "Audio compression (format %i)", v);
346  }
347 
348  avio_skip(pb, 12);
349  var_read_metadata(avctx, "title", 0x80);
350  var_read_metadata(avctx, "comment", 0x100);
351  avio_skip(pb, 0x80);
352 
353  timestamp = 0;
354  for (i = 0; i < vst->nb_frames; i++) {
355  uint32_t pos = avio_rb32(pb);
356  uint32_t asize = avio_rb32(pb);
357  uint32_t vsize = avio_rb32(pb);
358  if (avio_feof(pb))
359  return AVERROR_INVALIDDATA;
360  avio_skip(pb, 8);
361  av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
362  av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
363  timestamp += asize / (ast->codecpar->channels * 2LL);
364  }
365  } else if (!version && avio_rb16(pb) == 3) {
366  avio_skip(pb, 4);
367 
368  if ((ret = read_table(avctx, NULL, parse_global_var)) < 0)
369  return ret;
370 
371  if (mv->nb_audio_tracks < 0 || mv->nb_video_tracks < 0 ||
372  (mv->nb_audio_tracks == 0 && mv->nb_video_tracks == 0)) {
373  av_log(avctx, AV_LOG_ERROR, "Stream count is invalid.\n");
374  return AVERROR_INVALIDDATA;
375  }
376 
377  if (mv->nb_audio_tracks > 1) {
378  avpriv_request_sample(avctx, "Multiple audio streams support");
379  return AVERROR_PATCHWELCOME;
380  } else if (mv->nb_audio_tracks) {
381  ast = avformat_new_stream(avctx, NULL);
382  if (!ast)
383  return AVERROR(ENOMEM);
385  if ((read_table(avctx, ast, parse_audio_var)) < 0)
386  return ret;
387  if (mv->acompression == 100 &&
388  mv->aformat == AUDIO_FORMAT_SIGNED &&
389  ast->codecpar->bits_per_coded_sample == 16) {
391  } else {
392  avpriv_request_sample(avctx,
393  "Audio compression %i (format %i, sr %i)",
394  mv->acompression, mv->aformat,
397  }
398  if (ast->codecpar->channels <= 0) {
399  av_log(avctx, AV_LOG_ERROR, "No valid channel count found.\n");
400  return AVERROR_INVALIDDATA;
401  }
402  }
403 
404  if (mv->nb_video_tracks > 1) {
405  avpriv_request_sample(avctx, "Multiple video streams support");
406  return AVERROR_PATCHWELCOME;
407  } else if (mv->nb_video_tracks) {
408  vst = avformat_new_stream(avctx, NULL);
409  if (!vst)
410  return AVERROR(ENOMEM);
411  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
412  if ((ret = read_table(avctx, vst, parse_video_var))<0)
413  return ret;
414  }
415 
416  if (mv->nb_audio_tracks)
417  read_index(pb, ast);
418 
419  if (mv->nb_video_tracks)
420  read_index(pb, vst);
421  } else {
422  avpriv_request_sample(avctx, "Version %i", version);
423  return AVERROR_PATCHWELCOME;
424  }
425 
426  return 0;
427 }
428 
430 {
431  MvContext *mv = avctx->priv_data;
432  AVIOContext *pb = avctx->pb;
433  AVStream *st = avctx->streams[mv->stream_index];
434  const AVIndexEntry *index;
435  int frame = mv->frame[mv->stream_index];
436  int64_t ret;
437  uint64_t pos;
438 
439  if (frame < st->internal->nb_index_entries) {
440  index = &st->internal->index_entries[frame];
441  pos = avio_tell(pb);
442  if (index->pos > pos)
443  avio_skip(pb, index->pos - pos);
444  else if (index->pos < pos) {
445  if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
446  return AVERROR(EIO);
447  ret = avio_seek(pb, index->pos, SEEK_SET);
448  if (ret < 0)
449  return ret;
450  }
451  ret = av_get_packet(pb, pkt, index->size);
452  if (ret < 0)
453  return ret;
454 
455  pkt->stream_index = mv->stream_index;
456  pkt->pts = index->timestamp;
457  pkt->flags |= AV_PKT_FLAG_KEY;
458 
459  mv->frame[mv->stream_index]++;
460  mv->eof_count = 0;
461  } else {
462  mv->eof_count++;
463  if (mv->eof_count >= avctx->nb_streams)
464  return AVERROR_EOF;
465 
466  // avoid returning 0 without a packet
467  return AVERROR(EAGAIN);
468  }
469 
470  mv->stream_index++;
471  if (mv->stream_index >= avctx->nb_streams)
472  mv->stream_index = 0;
473 
474  return 0;
475 }
476 
478  int64_t timestamp, int flags)
479 {
480  MvContext *mv = avctx->priv_data;
481  AVStream *st = avctx->streams[stream_index];
482  int frame, i;
483 
484  if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
485  return AVERROR(ENOSYS);
486 
487  if (!(avctx->pb->seekable & AVIO_SEEKABLE_NORMAL))
488  return AVERROR(EIO);
489 
490  frame = av_index_search_timestamp(st, timestamp, flags);
491  if (frame < 0)
492  return AVERROR_INVALIDDATA;
493 
494  for (i = 0; i < avctx->nb_streams; i++)
495  mv->frame[i] = frame;
496  return 0;
497 }
498 
500  .name = "mv",
501  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
502  .priv_data_size = sizeof(MvContext),
503  .read_probe = mv_probe,
507 };
#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:283
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:1991
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:4905
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:341
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:770
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
static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: mvdec.c:429
Format I/O context.
Definition: avformat.h:1243
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:785
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:4481
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:1311
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:94
uint32_t tag
Definition: movenc.c:1597
#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:637
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
#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:1483
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:2108
static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t timestamp, int flags)
Definition: mvdec.c:477
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:115
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:369
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:231
static void read_index(AVIOContext *pb, AVStream *st)
Definition: mvdec.c:264
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:233
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1299
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:1285
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
int index
Definition: gxfenc.c:89
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define AVSEEK_FLAG_BYTE
seeking based on position in bytes
Definition: avformat.h:2412
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
AVInputFormat ff_mv_demuxer
Definition: mvdec.c:499
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:1271
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:2414
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:864
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:368
int stream_index
Definition: packet.h:365
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:340
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:356
int i
Definition: input.c:407
simple arithmetic expression evaluator
const char * name
Definition: opengl_enc.c:102