FFmpeg
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ffmdec.c
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1 /*
2  * FFM (ffserver live feed) demuxer
3  * Copyright (c) 2001 Fabrice Bellard
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 #include "libavutil/intreadwrite.h"
23 #include "libavutil/intfloat.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "ffm.h"
27 #include "avio_internal.h"
28 
29 static int ffm_is_avail_data(AVFormatContext *s, int size)
30 {
31  FFMContext *ffm = s->priv_data;
32  int64_t pos, avail_size;
33  int len;
34 
35  len = ffm->packet_end - ffm->packet_ptr;
36  if (size <= len)
37  return 1;
38  pos = avio_tell(s->pb);
39  if (!ffm->write_index) {
40  if (pos == ffm->file_size)
41  return AVERROR_EOF;
42  avail_size = ffm->file_size - pos;
43  } else {
44  if (pos == ffm->write_index) {
45  /* exactly at the end of stream */
46  return AVERROR(EAGAIN);
47  } else if (pos < ffm->write_index) {
48  avail_size = ffm->write_index - pos;
49  } else {
50  avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
51  }
52  }
53  avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
54  if (size <= avail_size)
55  return 1;
56  else
57  return AVERROR(EAGAIN);
58 }
59 
60 static int ffm_resync(AVFormatContext *s, int state)
61 {
62  av_log(s, AV_LOG_ERROR, "resyncing\n");
63  while (state != PACKET_ID) {
64  if (url_feof(s->pb)) {
65  av_log(s, AV_LOG_ERROR, "cannot find FFM syncword\n");
66  return -1;
67  }
68  state = (state << 8) | avio_r8(s->pb);
69  }
70  return 0;
71 }
72 
73 /* first is true if we read the frame header */
74 static int ffm_read_data(AVFormatContext *s,
75  uint8_t *buf, int size, int header)
76 {
77  FFMContext *ffm = s->priv_data;
78  AVIOContext *pb = s->pb;
79  int len, fill_size, size1, frame_offset, id;
80 
81  size1 = size;
82  while (size > 0) {
83  redo:
84  len = ffm->packet_end - ffm->packet_ptr;
85  if (len < 0)
86  return -1;
87  if (len > size)
88  len = size;
89  if (len == 0) {
90  if (avio_tell(pb) == ffm->file_size)
91  avio_seek(pb, ffm->packet_size, SEEK_SET);
92  retry_read:
93  if (pb->buffer_size != ffm->packet_size) {
94  int64_t tell = avio_tell(pb);
95  ffio_set_buf_size(pb, ffm->packet_size);
96  avio_seek(pb, tell, SEEK_SET);
97  }
98  id = avio_rb16(pb); /* PACKET_ID */
99  if (id != PACKET_ID)
100  if (ffm_resync(s, id) < 0)
101  return -1;
102  fill_size = avio_rb16(pb);
103  ffm->dts = avio_rb64(pb);
104  frame_offset = avio_rb16(pb);
105  avio_read(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
106  ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
107  if (ffm->packet_end < ffm->packet || frame_offset < 0)
108  return -1;
109  /* if first packet or resynchronization packet, we must
110  handle it specifically */
111  if (ffm->first_packet || (frame_offset & 0x8000)) {
112  if (!frame_offset) {
113  /* This packet has no frame headers in it */
114  if (avio_tell(pb) >= ffm->packet_size * 3LL) {
115  avio_seek(pb, -ffm->packet_size * 2LL, SEEK_CUR);
116  goto retry_read;
117  }
118  /* This is bad, we cannot find a valid frame header */
119  return 0;
120  }
121  ffm->first_packet = 0;
122  if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE)
123  return -1;
124  ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
125  if (!header)
126  break;
127  } else {
128  ffm->packet_ptr = ffm->packet;
129  }
130  goto redo;
131  }
132  memcpy(buf, ffm->packet_ptr, len);
133  buf += len;
134  ffm->packet_ptr += len;
135  size -= len;
136  header = 0;
137  }
138  return size1 - size;
139 }
140 
141 /* ensure that acutal seeking happens between FFM_PACKET_SIZE
142  and file_size - FFM_PACKET_SIZE */
143 static int64_t ffm_seek1(AVFormatContext *s, int64_t pos1)
144 {
145  FFMContext *ffm = s->priv_data;
146  AVIOContext *pb = s->pb;
147  int64_t pos;
148 
149  pos = FFMIN(pos1, ffm->file_size - FFM_PACKET_SIZE);
150  pos = FFMAX(pos, FFM_PACKET_SIZE);
151  av_dlog(s, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos);
152  return avio_seek(pb, pos, SEEK_SET);
153 }
154 
155 static int64_t get_dts(AVFormatContext *s, int64_t pos)
156 {
157  AVIOContext *pb = s->pb;
158  int64_t dts;
159 
160  ffm_seek1(s, pos);
161  avio_skip(pb, 4);
162  dts = avio_rb64(pb);
163  av_dlog(s, "dts=%0.6f\n", dts / 1000000.0);
164  return dts;
165 }
166 
167 static void adjust_write_index(AVFormatContext *s)
168 {
169  FFMContext *ffm = s->priv_data;
170  AVIOContext *pb = s->pb;
171  int64_t pts;
172  //int64_t orig_write_index = ffm->write_index;
173  int64_t pos_min, pos_max;
174  int64_t pts_start;
175  int64_t ptr = avio_tell(pb);
176 
177 
178  pos_min = 0;
179  pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
180 
181  pts_start = get_dts(s, pos_min);
182 
183  pts = get_dts(s, pos_max);
184 
185  if (pts - 100000 > pts_start)
186  goto end;
187 
188  ffm->write_index = FFM_PACKET_SIZE;
189 
190  pts_start = get_dts(s, pos_min);
191 
192  pts = get_dts(s, pos_max);
193 
194  if (pts - 100000 <= pts_start) {
195  while (1) {
196  int64_t newpos;
197  int64_t newpts;
198 
199  newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;
200 
201  if (newpos == pos_min)
202  break;
203 
204  newpts = get_dts(s, newpos);
205 
206  if (newpts - 100000 <= pts) {
207  pos_max = newpos;
208  pts = newpts;
209  } else {
210  pos_min = newpos;
211  }
212  }
213  ffm->write_index += pos_max;
214  }
215 
216  end:
217  avio_seek(pb, ptr, SEEK_SET);
218 }
219 
220 
221 static int ffm_close(AVFormatContext *s)
222 {
223  int i;
224 
225  for (i = 0; i < s->nb_streams; i++)
226  av_freep(&s->streams[i]->codec->rc_eq);
227 
228  return 0;
229 }
230 
231 static int ffm2_read_header(AVFormatContext *s)
232 {
233  FFMContext *ffm = s->priv_data;
234  AVStream *st;
235  AVIOContext *pb = s->pb;
236  AVCodecContext *codec;
237 
238  ffm->packet_size = avio_rb32(pb);
239  if (ffm->packet_size != FFM_PACKET_SIZE)
240  goto fail;
241  ffm->write_index = avio_rb64(pb);
242  /* get also filesize */
243  if (pb->seekable) {
244  ffm->file_size = avio_size(pb);
245  if (ffm->write_index && 0)
246  adjust_write_index(s);
247  } else {
248  ffm->file_size = (UINT64_C(1) << 63) - 1;
249  }
250 
251  while(!url_feof(pb)) {
252  unsigned id = avio_rb32(pb);
253  unsigned size = avio_rb32(pb);
254  int64_t next = avio_tell(pb) + size;
255  char rc_eq_buf[128];
256 
257  if(!id)
258  break;
259 
260  switch(id) {
261  case MKBETAG('M', 'A', 'I', 'N'):
262  avio_rb32(pb); /* nb_streams */
263  avio_rb32(pb); /* total bitrate */
264  break;
265  case MKBETAG('C', 'O', 'M', 'M'):
266  st = avformat_new_stream(s, NULL);
267  if (!st)
268  goto fail;
269 
270  avpriv_set_pts_info(st, 64, 1, 1000000);
271 
272  codec = st->codec;
273  /* generic info */
274  codec->codec_id = avio_rb32(pb);
275  codec->codec_type = avio_r8(pb);
276  codec->bit_rate = avio_rb32(pb);
277  codec->flags = avio_rb32(pb);
278  codec->flags2 = avio_rb32(pb);
279  codec->debug = avio_rb32(pb);
280  if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
281  codec->extradata_size = avio_rb32(pb);
282  codec->extradata = av_malloc(codec->extradata_size);
283  if (!codec->extradata)
284  return AVERROR(ENOMEM);
285  avio_read(pb, codec->extradata, codec->extradata_size);
286  }
287  avio_seek(pb, next, SEEK_SET);
288  id = avio_rb32(pb);
289  size = avio_rb32(pb);
290  next = avio_tell(pb) + size;
291  switch(id) {
292  case MKBETAG('S', 'T', 'V', 'I'):
293  codec->time_base.num = avio_rb32(pb);
294  codec->time_base.den = avio_rb32(pb);
295  codec->width = avio_rb16(pb);
296  codec->height = avio_rb16(pb);
297  codec->gop_size = avio_rb16(pb);
298  codec->pix_fmt = avio_rb32(pb);
299  codec->qmin = avio_r8(pb);
300  codec->qmax = avio_r8(pb);
301  codec->max_qdiff = avio_r8(pb);
302  codec->qcompress = avio_rb16(pb) / 10000.0;
303  codec->qblur = avio_rb16(pb) / 10000.0;
304  codec->bit_rate_tolerance = avio_rb32(pb);
305  avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf));
306  codec->rc_eq = av_strdup(rc_eq_buf);
307  codec->rc_max_rate = avio_rb32(pb);
308  codec->rc_min_rate = avio_rb32(pb);
309  codec->rc_buffer_size = avio_rb32(pb);
310  codec->i_quant_factor = av_int2double(avio_rb64(pb));
311  codec->b_quant_factor = av_int2double(avio_rb64(pb));
312  codec->i_quant_offset = av_int2double(avio_rb64(pb));
313  codec->b_quant_offset = av_int2double(avio_rb64(pb));
314  codec->dct_algo = avio_rb32(pb);
315  codec->strict_std_compliance = avio_rb32(pb);
316  codec->max_b_frames = avio_rb32(pb);
317  codec->mpeg_quant = avio_rb32(pb);
318  codec->intra_dc_precision = avio_rb32(pb);
319  codec->me_method = avio_rb32(pb);
320  codec->mb_decision = avio_rb32(pb);
321  codec->nsse_weight = avio_rb32(pb);
322  codec->frame_skip_cmp = avio_rb32(pb);
323  codec->rc_buffer_aggressivity = av_int2double(avio_rb64(pb));
324  codec->codec_tag = avio_rb32(pb);
325  codec->thread_count = avio_r8(pb);
326  codec->coder_type = avio_rb32(pb);
327  codec->me_cmp = avio_rb32(pb);
328  codec->me_subpel_quality = avio_rb32(pb);
329  codec->me_range = avio_rb32(pb);
330  codec->keyint_min = avio_rb32(pb);
331  codec->scenechange_threshold = avio_rb32(pb);
332  codec->b_frame_strategy = avio_rb32(pb);
333  codec->qcompress = av_int2double(avio_rb64(pb));
334  codec->qblur = av_int2double(avio_rb64(pb));
335  codec->max_qdiff = avio_rb32(pb);
336  codec->refs = avio_rb32(pb);
337  break;
338  case MKBETAG('S', 'T', 'A', 'U'):
339  codec->sample_rate = avio_rb32(pb);
340  codec->channels = avio_rl16(pb);
341  codec->frame_size = avio_rl16(pb);
342  break;
343  }
344  break;
345  }
346  avio_seek(pb, next, SEEK_SET);
347  }
348 
349  /* get until end of block reached */
350  while ((avio_tell(pb) % ffm->packet_size) != 0)
351  avio_r8(pb);
352 
353  /* init packet demux */
354  ffm->packet_ptr = ffm->packet;
355  ffm->packet_end = ffm->packet;
356  ffm->frame_offset = 0;
357  ffm->dts = 0;
358  ffm->read_state = READ_HEADER;
359  ffm->first_packet = 1;
360  return 0;
361  fail:
362  ffm_close(s);
363  return -1;
364 }
365 
366 static int ffm_read_header(AVFormatContext *s)
367 {
368  FFMContext *ffm = s->priv_data;
369  AVStream *st;
370  AVIOContext *pb = s->pb;
371  AVCodecContext *codec;
372  int i, nb_streams;
373  uint32_t tag;
374 
375  /* header */
376  tag = avio_rl32(pb);
377  if (tag == MKTAG('F', 'F', 'M', '2'))
378  return ffm2_read_header(s);
379  if (tag != MKTAG('F', 'F', 'M', '1'))
380  goto fail;
381  ffm->packet_size = avio_rb32(pb);
382  if (ffm->packet_size != FFM_PACKET_SIZE)
383  goto fail;
384  ffm->write_index = avio_rb64(pb);
385  /* get also filesize */
386  if (pb->seekable) {
387  ffm->file_size = avio_size(pb);
388  if (ffm->write_index && 0)
389  adjust_write_index(s);
390  } else {
391  ffm->file_size = (UINT64_C(1) << 63) - 1;
392  }
393 
394  nb_streams = avio_rb32(pb);
395  avio_rb32(pb); /* total bitrate */
396  /* read each stream */
397  for(i=0;i<nb_streams;i++) {
398  char rc_eq_buf[128];
399 
400  st = avformat_new_stream(s, NULL);
401  if (!st)
402  goto fail;
403 
404  avpriv_set_pts_info(st, 64, 1, 1000000);
405 
406  codec = st->codec;
407  /* generic info */
408  codec->codec_id = avio_rb32(pb);
409  codec->codec_type = avio_r8(pb); /* codec_type */
410  codec->bit_rate = avio_rb32(pb);
411  codec->flags = avio_rb32(pb);
412  codec->flags2 = avio_rb32(pb);
413  codec->debug = avio_rb32(pb);
414  /* specific info */
415  switch(codec->codec_type) {
416  case AVMEDIA_TYPE_VIDEO:
417  codec->time_base.num = avio_rb32(pb);
418  codec->time_base.den = avio_rb32(pb);
419  codec->width = avio_rb16(pb);
420  codec->height = avio_rb16(pb);
421  codec->gop_size = avio_rb16(pb);
422  codec->pix_fmt = avio_rb32(pb);
423  codec->qmin = avio_r8(pb);
424  codec->qmax = avio_r8(pb);
425  codec->max_qdiff = avio_r8(pb);
426  codec->qcompress = avio_rb16(pb) / 10000.0;
427  codec->qblur = avio_rb16(pb) / 10000.0;
428  codec->bit_rate_tolerance = avio_rb32(pb);
429  avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf));
430  codec->rc_eq = av_strdup(rc_eq_buf);
431  codec->rc_max_rate = avio_rb32(pb);
432  codec->rc_min_rate = avio_rb32(pb);
433  codec->rc_buffer_size = avio_rb32(pb);
434  codec->i_quant_factor = av_int2double(avio_rb64(pb));
435  codec->b_quant_factor = av_int2double(avio_rb64(pb));
436  codec->i_quant_offset = av_int2double(avio_rb64(pb));
437  codec->b_quant_offset = av_int2double(avio_rb64(pb));
438  codec->dct_algo = avio_rb32(pb);
439  codec->strict_std_compliance = avio_rb32(pb);
440  codec->max_b_frames = avio_rb32(pb);
441  codec->mpeg_quant = avio_rb32(pb);
442  codec->intra_dc_precision = avio_rb32(pb);
443  codec->me_method = avio_rb32(pb);
444  codec->mb_decision = avio_rb32(pb);
445  codec->nsse_weight = avio_rb32(pb);
446  codec->frame_skip_cmp = avio_rb32(pb);
447  codec->rc_buffer_aggressivity = av_int2double(avio_rb64(pb));
448  codec->codec_tag = avio_rb32(pb);
449  codec->thread_count = avio_r8(pb);
450  codec->coder_type = avio_rb32(pb);
451  codec->me_cmp = avio_rb32(pb);
452  codec->me_subpel_quality = avio_rb32(pb);
453  codec->me_range = avio_rb32(pb);
454  codec->keyint_min = avio_rb32(pb);
455  codec->scenechange_threshold = avio_rb32(pb);
456  codec->b_frame_strategy = avio_rb32(pb);
457  codec->qcompress = av_int2double(avio_rb64(pb));
458  codec->qblur = av_int2double(avio_rb64(pb));
459  codec->max_qdiff = avio_rb32(pb);
460  codec->refs = avio_rb32(pb);
461  break;
462  case AVMEDIA_TYPE_AUDIO:
463  codec->sample_rate = avio_rb32(pb);
464  codec->channels = avio_rl16(pb);
465  codec->frame_size = avio_rl16(pb);
466  break;
467  default:
468  goto fail;
469  }
470  if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
471  codec->extradata_size = avio_rb32(pb);
472  codec->extradata = av_malloc(codec->extradata_size);
473  if (!codec->extradata)
474  return AVERROR(ENOMEM);
475  avio_read(pb, codec->extradata, codec->extradata_size);
476  }
477  }
478 
479  /* get until end of block reached */
480  while ((avio_tell(pb) % ffm->packet_size) != 0)
481  avio_r8(pb);
482 
483  /* init packet demux */
484  ffm->packet_ptr = ffm->packet;
485  ffm->packet_end = ffm->packet;
486  ffm->frame_offset = 0;
487  ffm->dts = 0;
488  ffm->read_state = READ_HEADER;
489  ffm->first_packet = 1;
490  return 0;
491  fail:
492  ffm_close(s);
493  return -1;
494 }
495 
496 /* return < 0 if eof */
497 static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
498 {
499  int size;
500  FFMContext *ffm = s->priv_data;
501  int duration, ret;
502 
503  switch(ffm->read_state) {
504  case READ_HEADER:
505  if ((ret = ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) < 0)
506  return ret;
507 
508  av_dlog(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n",
509  avio_tell(s->pb), s->pb->pos, ffm->write_index, ffm->file_size);
510  if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=
511  FRAME_HEADER_SIZE)
512  return -1;
513  if (ffm->header[1] & FLAG_DTS)
514  if (ffm_read_data(s, ffm->header+16, 4, 1) != 4)
515  return -1;
516  ffm->read_state = READ_DATA;
517  /* fall thru */
518  case READ_DATA:
519  size = AV_RB24(ffm->header + 2);
520  if ((ret = ffm_is_avail_data(s, size)) < 0)
521  return ret;
522 
523  duration = AV_RB24(ffm->header + 5);
524 
525  if (av_new_packet(pkt, size) < 0) {
526  return AVERROR(ENOMEM);
527  }
528  pkt->stream_index = ffm->header[0];
529  if ((unsigned)pkt->stream_index >= s->nb_streams) {
530  av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index);
531  av_free_packet(pkt);
532  ffm->read_state = READ_HEADER;
533  return -1;
534  }
535  pkt->pos = avio_tell(s->pb);
536  if (ffm->header[1] & FLAG_KEY_FRAME)
537  pkt->flags |= AV_PKT_FLAG_KEY;
538 
539  ffm->read_state = READ_HEADER;
540  if (ffm_read_data(s, pkt->data, size, 0) != size) {
541  /* bad case: desynchronized packet. we cancel all the packet loading */
542  av_free_packet(pkt);
543  return -1;
544  }
545  pkt->pts = AV_RB64(ffm->header+8);
546  if (ffm->header[1] & FLAG_DTS)
547  pkt->dts = pkt->pts - AV_RB32(ffm->header+16);
548  else
549  pkt->dts = pkt->pts;
550  pkt->duration = duration;
551  break;
552  }
553  return 0;
554 }
555 
556 /* seek to a given time in the file. The file read pointer is
557  positioned at or before pts. XXX: the following code is quite
558  approximative */
559 static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)
560 {
561  FFMContext *ffm = s->priv_data;
562  int64_t pos_min, pos_max, pos;
563  int64_t pts_min, pts_max, pts;
564  double pos1;
565 
566  av_dlog(s, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
567  /* find the position using linear interpolation (better than
568  dichotomy in typical cases) */
569  if (ffm->write_index && ffm->write_index < ffm->file_size) {
570  if (get_dts(s, FFM_PACKET_SIZE) < wanted_pts) {
571  pos_min = FFM_PACKET_SIZE;
572  pos_max = ffm->write_index - FFM_PACKET_SIZE;
573  } else {
574  pos_min = ffm->write_index;
575  pos_max = ffm->file_size - FFM_PACKET_SIZE;
576  }
577  } else {
578  pos_min = FFM_PACKET_SIZE;
579  pos_max = ffm->file_size - FFM_PACKET_SIZE;
580  }
581  while (pos_min <= pos_max) {
582  pts_min = get_dts(s, pos_min);
583  pts_max = get_dts(s, pos_max);
584  if (pts_min > wanted_pts || pts_max <= wanted_pts) {
585  pos = pts_min > wanted_pts ? pos_min : pos_max;
586  goto found;
587  }
588  /* linear interpolation */
589  pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
590  (double)(pts_max - pts_min);
591  pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
592  if (pos <= pos_min)
593  pos = pos_min;
594  else if (pos >= pos_max)
595  pos = pos_max;
596  pts = get_dts(s, pos);
597  /* check if we are lucky */
598  if (pts == wanted_pts) {
599  goto found;
600  } else if (pts > wanted_pts) {
601  pos_max = pos - FFM_PACKET_SIZE;
602  } else {
603  pos_min = pos + FFM_PACKET_SIZE;
604  }
605  }
606  pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;
607 
608  found:
609  if (ffm_seek1(s, pos) < 0)
610  return -1;
611 
612  /* reset read state */
613  ffm->read_state = READ_HEADER;
614  ffm->packet_ptr = ffm->packet;
615  ffm->packet_end = ffm->packet;
616  ffm->first_packet = 1;
617 
618  return 0;
619 }
620 
621 static int ffm_probe(AVProbeData *p)
622 {
623  if (
624  p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&
625  (p->buf[3] == '1' || p->buf[3] == '2'))
626  return AVPROBE_SCORE_MAX + 1;
627  return 0;
628 }
629 
630 AVInputFormat ff_ffm_demuxer = {
631  .name = "ffm",
632  .long_name = NULL_IF_CONFIG_SMALL("FFM (FFserver live feed)"),
633  .priv_data_size = sizeof(FFMContext),
634  .read_probe = ffm_probe,
635  .read_header = ffm_read_header,
636  .read_packet = ffm_read_packet,
637  .read_close = ffm_close,
638  .read_seek = ffm_seek,
639 };
Generated on Sat May 25 2013 03:58:46 for FFmpeg by   doxygen 1.8.2