avidec.c
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1 /*
2  * AVI demuxer
3  * Copyright (c) 2001 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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/mathematics.h"
24 #include "libavutil/bswap.h"
25 #include "libavutil/dict.h"
26 #include "libavutil/avstring.h"
27 #include "avformat.h"
28 #include "internal.h"
29 #include "avi.h"
30 #include "dv.h"
31 #include "riff.h"
32 
33 #undef NDEBUG
34 #include <assert.h>
35 
36 typedef struct AVIStream {
37  int64_t frame_offset; /* current frame (video) or byte (audio) counter
38  (used to compute the pts) */
39  int remaining;
41 
42  uint32_t scale;
43  uint32_t rate;
44  int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
45 
46  int64_t cum_len; /* temporary storage (used during seek) */
47 
48  int prefix;
50  uint32_t pal[256];
51  int has_pal;
53 
57 } AVIStream;
58 
59 typedef struct {
60  int64_t riff_end;
61  int64_t movi_end;
62  int64_t fsize;
63  int64_t movi_list;
64  int64_t last_pkt_pos;
66  int is_odml;
71 #define MAX_ODML_DEPTH 1000
72 } AVIContext;
73 
74 static const char avi_headers[][8] = {
75  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
76  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
77  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19},
78  { 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
79  { 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
80  { 0 }
81 };
82 
84  { "strn", "title" },
85  { 0 },
86 };
87 
88 static int avi_load_index(AVFormatContext *s);
89 static int guess_ni_flag(AVFormatContext *s);
90 
91 #define print_tag(str, tag, size) \
92  av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n", \
93  str, tag & 0xff, \
94  (tag >> 8) & 0xff, \
95  (tag >> 16) & 0xff, \
96  (tag >> 24) & 0xff, \
97  size)
98 
99 static inline int get_duration(AVIStream *ast, int len){
100  if(ast->sample_size){
101  return len;
102  }else if (ast->dshow_block_align){
103  return (len + ast->dshow_block_align - 1)/ast->dshow_block_align;
104  }else
105  return 1;
106 }
107 
109 {
110  AVIContext *avi = s->priv_data;
111  char header[8];
112  int i;
113 
114  /* check RIFF header */
115  avio_read(pb, header, 4);
116  avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
117  avi->riff_end += avio_tell(pb); /* RIFF chunk end */
118  avio_read(pb, header+4, 4);
119 
120  for(i=0; avi_headers[i][0]; i++)
121  if(!memcmp(header, avi_headers[i], 8))
122  break;
123  if(!avi_headers[i][0])
124  return -1;
125 
126  if(header[7] == 0x19)
127  av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");
128 
129  return 0;
130 }
131 
132 static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
133  AVIContext *avi = s->priv_data;
134  AVIOContext *pb = s->pb;
135  int longs_pre_entry= avio_rl16(pb);
136  int index_sub_type = avio_r8(pb);
137  int index_type = avio_r8(pb);
138  int entries_in_use = avio_rl32(pb);
139  int chunk_id = avio_rl32(pb);
140  int64_t base = avio_rl64(pb);
141  int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
142  AVStream *st;
143  AVIStream *ast;
144  int i;
145  int64_t last_pos= -1;
146  int64_t filesize= avio_size(s->pb);
147 
148  av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",
149  longs_pre_entry,index_type, entries_in_use, chunk_id, base);
150 
151  if(stream_id >= s->nb_streams || stream_id < 0)
152  return -1;
153  st= s->streams[stream_id];
154  ast = st->priv_data;
155 
156  if(index_sub_type)
157  return -1;
158 
159  avio_rl32(pb);
160 
161  if(index_type && longs_pre_entry != 2)
162  return -1;
163  if(index_type>1)
164  return -1;
165 
166  if(filesize > 0 && base >= filesize){
167  av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
168  if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)
169  base &= 0xFFFFFFFF;
170  else
171  return -1;
172  }
173 
174  for(i=0; i<entries_in_use; i++){
175  if(index_type){
176  int64_t pos= avio_rl32(pb) + base - 8;
177  int len = avio_rl32(pb);
178  int key= len >= 0;
179  len &= 0x7FFFFFFF;
180 
181  av_dlog(s, "pos:%"PRId64", len:%X\n", pos, len);
182 
183  if(pb->eof_reached)
184  return -1;
185 
186  if(last_pos == pos || pos == base - 8)
187  avi->non_interleaved= 1;
188  if(last_pos != pos && (len || !ast->sample_size))
189  av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
190 
191  ast->cum_len += get_duration(ast, len);
192  last_pos= pos;
193  }else{
194  int64_t offset, pos;
195  int duration;
196  offset = avio_rl64(pb);
197  avio_rl32(pb); /* size */
198  duration = avio_rl32(pb);
199 
200  if(pb->eof_reached)
201  return -1;
202 
203  pos = avio_tell(pb);
204 
205  if(avi->odml_depth > MAX_ODML_DEPTH){
206  av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
207  return -1;
208  }
209 
210  avio_seek(pb, offset+8, SEEK_SET);
211  avi->odml_depth++;
212  read_braindead_odml_indx(s, frame_num);
213  avi->odml_depth--;
214  frame_num += duration;
215 
216  avio_seek(pb, pos, SEEK_SET);
217  }
218  }
219  avi->index_loaded=1;
220  return 0;
221 }
222 
223 static void clean_index(AVFormatContext *s){
224  int i;
225  int64_t j;
226 
227  for(i=0; i<s->nb_streams; i++){
228  AVStream *st = s->streams[i];
229  AVIStream *ast = st->priv_data;
230  int n= st->nb_index_entries;
231  int max= ast->sample_size;
232  int64_t pos, size, ts;
233 
234  if(n != 1 || ast->sample_size==0)
235  continue;
236 
237  while(max < 1024) max+=max;
238 
239  pos= st->index_entries[0].pos;
240  size= st->index_entries[0].size;
241  ts= st->index_entries[0].timestamp;
242 
243  for(j=0; j<size; j+=max){
244  av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
245  }
246  }
247 }
248 
249 static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)
250 {
251  AVIOContext *pb = s->pb;
252  char key[5] = {0}, *value;
253 
254  size += (size & 1);
255 
256  if (size == UINT_MAX)
257  return -1;
258  value = av_malloc(size+1);
259  if (!value)
260  return -1;
261  avio_read(pb, value, size);
262  value[size]=0;
263 
264  AV_WL32(key, tag);
265 
266  return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
268 }
269 
270 static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
271  "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
272 
273 static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
274 {
275  char month[4], time[9], buffer[64];
276  int i, day, year;
277  /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
278  if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
279  month, &day, time, &year) == 4) {
280  for (i=0; i<12; i++)
281  if (!av_strcasecmp(month, months[i])) {
282  snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
283  year, i+1, day, time);
284  av_dict_set(metadata, "creation_time", buffer, 0);
285  }
286  } else if (date[4] == '/' && date[7] == '/') {
287  date[4] = date[7] = '-';
288  av_dict_set(metadata, "creation_time", date, 0);
289  }
290 }
291 
292 static void avi_read_nikon(AVFormatContext *s, uint64_t end)
293 {
294  while (avio_tell(s->pb) < end) {
295  uint32_t tag = avio_rl32(s->pb);
296  uint32_t size = avio_rl32(s->pb);
297  switch (tag) {
298  case MKTAG('n', 'c', 't', 'g'): { /* Nikon Tags */
299  uint64_t tag_end = avio_tell(s->pb) + size;
300  while (avio_tell(s->pb) < tag_end) {
301  uint16_t tag = avio_rl16(s->pb);
302  uint16_t size = avio_rl16(s->pb);
303  const char *name = NULL;
304  char buffer[64] = {0};
305  size -= avio_read(s->pb, buffer,
306  FFMIN(size, sizeof(buffer)-1));
307  switch (tag) {
308  case 0x03: name = "maker"; break;
309  case 0x04: name = "model"; break;
310  case 0x13: name = "creation_time";
311  if (buffer[4] == ':' && buffer[7] == ':')
312  buffer[4] = buffer[7] = '-';
313  break;
314  }
315  if (name)
316  av_dict_set(&s->metadata, name, buffer, 0);
317  avio_skip(s->pb, size);
318  }
319  break;
320  }
321  default:
322  avio_skip(s->pb, size);
323  break;
324  }
325  }
326 }
327 
329 {
330  AVIContext *avi = s->priv_data;
331  AVIOContext *pb = s->pb;
332  unsigned int tag, tag1, handler;
333  int codec_type, stream_index, frame_period;
334  unsigned int size;
335  int i;
336  AVStream *st;
337  AVIStream *ast = NULL;
338  int avih_width=0, avih_height=0;
339  int amv_file_format=0;
340  uint64_t list_end = 0;
341  int ret;
342 
343  avi->stream_index= -1;
344 
345  if (get_riff(s, pb) < 0)
346  return -1;
347 
348  avi->fsize = avio_size(pb);
349  if(avi->fsize<=0)
350  avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
351 
352  /* first list tag */
353  stream_index = -1;
354  codec_type = -1;
355  frame_period = 0;
356  for(;;) {
357  if (pb->eof_reached)
358  goto fail;
359  tag = avio_rl32(pb);
360  size = avio_rl32(pb);
361 
362  print_tag("tag", tag, size);
363 
364  switch(tag) {
365  case MKTAG('L', 'I', 'S', 'T'):
366  list_end = avio_tell(pb) + size;
367  /* Ignored, except at start of video packets. */
368  tag1 = avio_rl32(pb);
369 
370  print_tag("list", tag1, 0);
371 
372  if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
373  avi->movi_list = avio_tell(pb) - 4;
374  if(size) avi->movi_end = avi->movi_list + size + (size & 1);
375  else avi->movi_end = avio_size(pb);
376  av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
377  goto end_of_header;
378  }
379  else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
380  ff_read_riff_info(s, size - 4);
381  else if (tag1 == MKTAG('n', 'c', 'd', 't'))
382  avi_read_nikon(s, list_end);
383 
384  break;
385  case MKTAG('I', 'D', 'I', 'T'): {
386  unsigned char date[64] = {0};
387  size += (size & 1);
388  size -= avio_read(pb, date, FFMIN(size, sizeof(date)-1));
389  avio_skip(pb, size);
391  break;
392  }
393  case MKTAG('d', 'm', 'l', 'h'):
394  avi->is_odml = 1;
395  avio_skip(pb, size + (size & 1));
396  break;
397  case MKTAG('a', 'm', 'v', 'h'):
398  amv_file_format=1;
399  case MKTAG('a', 'v', 'i', 'h'):
400  /* AVI header */
401  /* using frame_period is bad idea */
402  frame_period = avio_rl32(pb);
403  avio_skip(pb, 4);
404  avio_rl32(pb);
406 
407  avio_skip(pb, 2 * 4);
408  avio_rl32(pb);
409  avio_rl32(pb);
410  avih_width=avio_rl32(pb);
411  avih_height=avio_rl32(pb);
412 
413  avio_skip(pb, size - 10 * 4);
414  break;
415  case MKTAG('s', 't', 'r', 'h'):
416  /* stream header */
417 
418  tag1 = avio_rl32(pb);
419  handler = avio_rl32(pb); /* codec tag */
420 
421  if(tag1 == MKTAG('p', 'a', 'd', 's')){
422  avio_skip(pb, size - 8);
423  break;
424  }else{
425  stream_index++;
426  st = avformat_new_stream(s, NULL);
427  if (!st)
428  goto fail;
429 
430  st->id = stream_index;
431  ast = av_mallocz(sizeof(AVIStream));
432  if (!ast)
433  goto fail;
434  st->priv_data = ast;
435  }
436  if(amv_file_format)
437  tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');
438 
439  print_tag("strh", tag1, -1);
440 
441  if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
442  int64_t dv_dur;
443 
444  /*
445  * After some consideration -- I don't think we
446  * have to support anything but DV in type1 AVIs.
447  */
448  if (s->nb_streams != 1)
449  goto fail;
450 
451  if (handler != MKTAG('d', 'v', 's', 'd') &&
452  handler != MKTAG('d', 'v', 'h', 'd') &&
453  handler != MKTAG('d', 'v', 's', 'l'))
454  goto fail;
455 
456  ast = s->streams[0]->priv_data;
457  av_freep(&s->streams[0]->codec->extradata);
458  av_freep(&s->streams[0]->codec);
459  av_freep(&s->streams[0]);
460  s->nb_streams = 0;
461  if (CONFIG_DV_DEMUXER) {
462  avi->dv_demux = avpriv_dv_init_demux(s);
463  if (!avi->dv_demux)
464  goto fail;
465  }
466  s->streams[0]->priv_data = ast;
467  avio_skip(pb, 3 * 4);
468  ast->scale = avio_rl32(pb);
469  ast->rate = avio_rl32(pb);
470  avio_skip(pb, 4); /* start time */
471 
472  dv_dur = avio_rl32(pb);
473  if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
474  dv_dur *= AV_TIME_BASE;
475  s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
476  }
477  /*
478  * else, leave duration alone; timing estimation in utils.c
479  * will make a guess based on bitrate.
480  */
481 
482  stream_index = s->nb_streams - 1;
483  avio_skip(pb, size - 9*4);
484  break;
485  }
486 
487  assert(stream_index < s->nb_streams);
488  st->codec->stream_codec_tag= handler;
489 
490  avio_rl32(pb); /* flags */
491  avio_rl16(pb); /* priority */
492  avio_rl16(pb); /* language */
493  avio_rl32(pb); /* initial frame */
494  ast->scale = avio_rl32(pb);
495  ast->rate = avio_rl32(pb);
496  if(!(ast->scale && ast->rate)){
497  av_log(s, AV_LOG_WARNING, "scale/rate is %u/%u which is invalid. (This file has been generated by broken software.)\n", ast->scale, ast->rate);
498  if(frame_period){
499  ast->rate = 1000000;
500  ast->scale = frame_period;
501  }else{
502  ast->rate = 25;
503  ast->scale = 1;
504  }
505  }
506  avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
507 
508  ast->cum_len=avio_rl32(pb); /* start */
509  st->nb_frames = avio_rl32(pb);
510 
511  st->start_time = 0;
512  avio_rl32(pb); /* buffer size */
513  avio_rl32(pb); /* quality */
514  ast->sample_size = avio_rl32(pb); /* sample ssize */
515  ast->cum_len *= FFMAX(1, ast->sample_size);
516  av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",
517  ast->rate, ast->scale, ast->sample_size);
518 
519  switch(tag1) {
520  case MKTAG('v', 'i', 'd', 's'):
521  codec_type = AVMEDIA_TYPE_VIDEO;
522 
523  ast->sample_size = 0;
524  break;
525  case MKTAG('a', 'u', 'd', 's'):
526  codec_type = AVMEDIA_TYPE_AUDIO;
527  break;
528  case MKTAG('t', 'x', 't', 's'):
529  codec_type = AVMEDIA_TYPE_SUBTITLE;
530  break;
531  case MKTAG('d', 'a', 't', 's'):
532  codec_type = AVMEDIA_TYPE_DATA;
533  break;
534  default:
535  av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
536  goto fail;
537  }
538  if(ast->sample_size == 0)
539  st->duration = st->nb_frames;
540  ast->frame_offset= ast->cum_len;
541  avio_skip(pb, size - 12 * 4);
542  break;
543  case MKTAG('s', 't', 'r', 'f'):
544  /* stream header */
545  if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
546  avio_skip(pb, size);
547  } else {
548  uint64_t cur_pos = avio_tell(pb);
549  if (cur_pos < list_end)
550  size = FFMIN(size, list_end - cur_pos);
551  st = s->streams[stream_index];
552  switch(codec_type) {
553  case AVMEDIA_TYPE_VIDEO:
554  if(amv_file_format){
555  st->codec->width=avih_width;
556  st->codec->height=avih_height;
559  avio_skip(pb, size);
560  break;
561  }
562  tag1 = ff_get_bmp_header(pb, st);
563 
564  if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {
566  st->codec->codec_tag = tag1;
568  break;
569  }
570 
571  if(size > 10*4 && size<(1<<30)){
572  st->codec->extradata_size= size - 10*4;
574  if (!st->codec->extradata) {
575  st->codec->extradata_size= 0;
576  return AVERROR(ENOMEM);
577  }
578  avio_read(pb, st->codec->extradata, st->codec->extradata_size);
579  }
580 
581  if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
582  avio_r8(pb);
583 
584  /* Extract palette from extradata if bpp <= 8. */
585  /* This code assumes that extradata contains only palette. */
586  /* This is true for all paletted codecs implemented in Libav. */
587  if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
588  int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
589  const uint8_t *pal_src;
590 
591  pal_size = FFMIN(pal_size, st->codec->extradata_size);
592  pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;
593 #if HAVE_BIGENDIAN
594  for (i = 0; i < pal_size/4; i++)
595  ast->pal[i] = av_bswap32(((uint32_t*)pal_src)[i]);
596 #else
597  memcpy(ast->pal, pal_src, pal_size);
598 #endif
599  ast->has_pal = 1;
600  }
601 
602  print_tag("video", tag1, 0);
603 
605  st->codec->codec_tag = tag1;
607  st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
608  // Support "Resolution 1:1" for Avid AVI Codec
609  if(tag1 == MKTAG('A', 'V', 'R', 'n') &&
610  st->codec->extradata_size >= 31 &&
611  !memcmp(&st->codec->extradata[28], "1:1", 3))
613 
614  if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
615  st->codec->extradata_size+= 9;
617  if(st->codec->extradata)
618  memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
619  }
620  st->codec->height= FFABS(st->codec->height);
621 
622 // avio_skip(pb, size - 5 * 4);
623  break;
624  case AVMEDIA_TYPE_AUDIO:
625  ret = ff_get_wav_header(pb, st->codec, size);
626  if (ret < 0)
627  return ret;
629  if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
630  av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
631  ast->sample_size= st->codec->block_align;
632  }
633  if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
634  avio_skip(pb, 1);
635  /* Force parsing as several audio frames can be in
636  * one packet and timestamps refer to packet start. */
638  /* ADTS header is in extradata, AAC without header must be
639  * stored as exact frames. Parser not needed and it will
640  * fail. */
641  if (st->codec->codec_id == AV_CODEC_ID_AAC && st->codec->extradata_size)
643  /* AVI files with Xan DPCM audio (wrongly) declare PCM
644  * audio in the header but have Axan as stream_code_tag. */
645  if (st->codec->stream_codec_tag == AV_RL32("Axan")){
647  st->codec->codec_tag = 0;
648  }
649  if (amv_file_format){
651  ast->dshow_block_align = 0;
652  }
653  break;
657  break;
658  default:
661  st->codec->codec_tag= 0;
662  avio_skip(pb, size);
663  break;
664  }
665  }
666  break;
667  case MKTAG('i', 'n', 'd', 'x'):
668  i= avio_tell(pb);
669  if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) &&
670  read_braindead_odml_indx(s, 0) < 0 &&
672  goto fail;
673  avio_seek(pb, i+size, SEEK_SET);
674  break;
675  case MKTAG('v', 'p', 'r', 'p'):
676  if(stream_index < (unsigned)s->nb_streams && size > 9*4){
677  AVRational active, active_aspect;
678 
679  st = s->streams[stream_index];
680  avio_rl32(pb);
681  avio_rl32(pb);
682  avio_rl32(pb);
683  avio_rl32(pb);
684  avio_rl32(pb);
685 
686  active_aspect.den= avio_rl16(pb);
687  active_aspect.num= avio_rl16(pb);
688  active.num = avio_rl32(pb);
689  active.den = avio_rl32(pb);
690  avio_rl32(pb); //nbFieldsPerFrame
691 
692  if(active_aspect.num && active_aspect.den && active.num && active.den){
693  st->sample_aspect_ratio= av_div_q(active_aspect, active);
694  av_dlog(s, "vprp %d/%d %d/%d\n",
695  active_aspect.num, active_aspect.den,
696  active.num, active.den);
697  }
698  size -= 9*4;
699  }
700  avio_skip(pb, size);
701  break;
702  case MKTAG('s', 't', 'r', 'n'):
703  if(s->nb_streams){
704  avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);
705  break;
706  }
707  default:
708  if(size > 1000000){
709  av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
710  "I will ignore it and try to continue anyway.\n");
712  goto fail;
713  avi->movi_list = avio_tell(pb) - 4;
714  avi->movi_end = avio_size(pb);
715  goto end_of_header;
716  }
717  /* skip tag */
718  size += (size & 1);
719  avio_skip(pb, size);
720  break;
721  }
722  }
723  end_of_header:
724  /* check stream number */
725  if (stream_index != s->nb_streams - 1) {
726  fail:
727  return -1;
728  }
729 
730  if(!avi->index_loaded && pb->seekable)
731  avi_load_index(s);
732  avi->index_loaded = 1;
733  avi->non_interleaved |= guess_ni_flag(s);
734  for(i=0; i<s->nb_streams; i++){
735  AVStream *st = s->streams[i];
736  if(st->nb_index_entries)
737  break;
738  }
739  if(i==s->nb_streams && avi->non_interleaved) {
740  av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");
741  avi->non_interleaved=0;
742  }
743 
744  if(avi->non_interleaved) {
745  av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
746  clean_index(s);
747  }
748 
749  ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
751 
752  return 0;
753 }
754 
755 static int read_gab2_sub(AVStream *st, AVPacket *pkt)
756 {
757  if (pkt->size >= 7 &&
758  !strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data + 5) == 2) {
759  uint8_t desc[256];
760  int score = AVPROBE_SCORE_MAX / 2, ret;
761  AVIStream *ast = st->priv_data;
762  AVInputFormat *sub_demuxer;
763  AVRational time_base;
764  AVIOContext *pb = avio_alloc_context( pkt->data + 7,
765  pkt->size - 7,
766  0, NULL, NULL, NULL, NULL);
767  AVProbeData pd;
768  unsigned int desc_len = avio_rl32(pb);
769 
770  if (desc_len > pb->buf_end - pb->buf_ptr)
771  goto error;
772 
773  ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
774  avio_skip(pb, desc_len - ret);
775  if (*desc)
776  av_dict_set(&st->metadata, "title", desc, 0);
777 
778  avio_rl16(pb); /* flags? */
779  avio_rl32(pb); /* data size */
780 
781  pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };
782  if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
783  goto error;
784 
785  if (!(ast->sub_ctx = avformat_alloc_context()))
786  goto error;
787 
788  ast->sub_ctx->pb = pb;
789  if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
790  ff_read_packet(ast->sub_ctx, &ast->sub_pkt);
791  *st->codec = *ast->sub_ctx->streams[0]->codec;
792  ast->sub_ctx->streams[0]->codec->extradata = NULL;
793  time_base = ast->sub_ctx->streams[0]->time_base;
794  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
795  }
796  ast->sub_buffer = pkt->data;
797  memset(pkt, 0, sizeof(*pkt));
798  return 1;
799 error:
800  av_freep(&pb);
801  }
802  return 0;
803 }
804 
806  AVPacket *pkt)
807 {
808  AVIStream *ast, *next_ast = next_st->priv_data;
809  int64_t ts, next_ts, ts_min = INT64_MAX;
810  AVStream *st, *sub_st = NULL;
811  int i;
812 
813  next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
815 
816  for (i=0; i<s->nb_streams; i++) {
817  st = s->streams[i];
818  ast = st->priv_data;
819  if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
821  if (ts <= next_ts && ts < ts_min) {
822  ts_min = ts;
823  sub_st = st;
824  }
825  }
826  }
827 
828  if (sub_st) {
829  ast = sub_st->priv_data;
830  *pkt = ast->sub_pkt;
831  pkt->stream_index = sub_st->index;
832  if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
833  ast->sub_pkt.data = NULL;
834  }
835  return sub_st;
836 }
837 
838 static int get_stream_idx(int *d){
839  if( d[0] >= '0' && d[0] <= '9'
840  && d[1] >= '0' && d[1] <= '9'){
841  return (d[0] - '0') * 10 + (d[1] - '0');
842  }else{
843  return 100; //invalid stream ID
844  }
845 }
846 
847 static int avi_sync(AVFormatContext *s, int exit_early)
848 {
849  AVIContext *avi = s->priv_data;
850  AVIOContext *pb = s->pb;
851  int n;
852  unsigned int d[8];
853  unsigned int size;
854  int64_t i, sync;
855 
856 start_sync:
857  memset(d, -1, sizeof(d));
858  for(i=sync=avio_tell(pb); !pb->eof_reached; i++) {
859  int j;
860 
861  for(j=0; j<7; j++)
862  d[j]= d[j+1];
863  d[7]= avio_r8(pb);
864 
865  size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
866 
867  n= get_stream_idx(d+2);
868  av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",
869  d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
870  if(i + (uint64_t)size > avi->fsize || d[0] > 127)
871  continue;
872 
873  //parse ix##
874  if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
875  //parse JUNK
876  ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')
877  ||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){
878  avio_skip(pb, size);
879  goto start_sync;
880  }
881 
882  //parse stray LIST
883  if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){
884  avio_skip(pb, 4);
885  goto start_sync;
886  }
887 
888  n= get_stream_idx(d);
889 
890  if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
891  continue;
892 
893  //detect ##ix chunk and skip
894  if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){
895  avio_skip(pb, size);
896  goto start_sync;
897  }
898 
899  //parse ##dc/##wb
900  if(n < s->nb_streams){
901  AVStream *st;
902  AVIStream *ast;
903  st = s->streams[n];
904  ast = st->priv_data;
905 
906  if(s->nb_streams>=2){
907  AVStream *st1 = s->streams[1];
908  AVIStream *ast1= st1->priv_data;
909  //workaround for broken small-file-bug402.avi
910  if( d[2] == 'w' && d[3] == 'b'
911  && n==0
912  && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
914  && ast->prefix == 'd'*256+'c'
915  && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
916  ){
917  n=1;
918  st = st1;
919  ast = ast1;
920  av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
921  }
922  }
923 
924 
925  if (!avi->dv_demux &&
926  ((st->discard >= AVDISCARD_DEFAULT && size==0) /* ||
927  //FIXME needs a little reordering
928  (st->discard >= AVDISCARD_NONKEY &&
929  !(pkt->flags & AV_PKT_FLAG_KEY)) */
930  || st->discard >= AVDISCARD_ALL)) {
931  if (!exit_early) {
932  ast->frame_offset += get_duration(ast, size);
933  }
934  avio_skip(pb, size);
935  goto start_sync;
936  }
937 
938  if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
939  int k = avio_r8(pb);
940  int last = (k + avio_r8(pb) - 1) & 0xFF;
941 
942  avio_rl16(pb); //flags
943 
944  for (; k <= last; k++)
945  ast->pal[k] = avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);
946  ast->has_pal= 1;
947  goto start_sync;
948  } else if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
949  d[2]*256+d[3] == ast->prefix /*||
950  (d[2] == 'd' && d[3] == 'c') ||
951  (d[2] == 'w' && d[3] == 'b')*/) {
952 
953  if (exit_early)
954  return 0;
955  if(d[2]*256+d[3] == ast->prefix)
956  ast->prefix_count++;
957  else{
958  ast->prefix= d[2]*256+d[3];
959  ast->prefix_count= 0;
960  }
961 
962  avi->stream_index= n;
963  ast->packet_size= size + 8;
964  ast->remaining= size;
965 
966  if(size || !ast->sample_size){
967  uint64_t pos= avio_tell(pb) - 8;
968  if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
969  av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);
970  }
971  }
972  return 0;
973  }
974  }
975  }
976 
977  return AVERROR_EOF;
978 }
979 
981 {
982  AVIContext *avi = s->priv_data;
983  AVIOContext *pb = s->pb;
984  int err;
985  void* dstr;
986 
987  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
988  int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
989  if (size >= 0)
990  return size;
991  }
992 
993  if(avi->non_interleaved){
994  int best_stream_index = 0;
995  AVStream *best_st= NULL;
996  AVIStream *best_ast;
997  int64_t best_ts= INT64_MAX;
998  int i;
999 
1000  for(i=0; i<s->nb_streams; i++){
1001  AVStream *st = s->streams[i];
1002  AVIStream *ast = st->priv_data;
1003  int64_t ts= ast->frame_offset;
1004  int64_t last_ts;
1005 
1006  if(!st->nb_index_entries)
1007  continue;
1008 
1009  last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
1010  if(!ast->remaining && ts > last_ts)
1011  continue;
1012 
1013  ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});
1014 
1015  av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,
1016  st->time_base.num, st->time_base.den, ast->frame_offset);
1017  if(ts < best_ts){
1018  best_ts= ts;
1019  best_st= st;
1020  best_stream_index= i;
1021  }
1022  }
1023  if(!best_st)
1024  return -1;
1025 
1026  best_ast = best_st->priv_data;
1027  best_ts = av_rescale_q(best_ts, (AVRational){FFMAX(1, best_ast->sample_size), AV_TIME_BASE}, best_st->time_base);
1028  if(best_ast->remaining)
1030  else{
1031  i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
1032  if(i>=0)
1033  best_ast->frame_offset= best_st->index_entries[i].timestamp;
1034  }
1035 
1036  if(i>=0){
1037  int64_t pos= best_st->index_entries[i].pos;
1038  pos += best_ast->packet_size - best_ast->remaining;
1039  avio_seek(s->pb, pos + 8, SEEK_SET);
1040 
1041  assert(best_ast->remaining <= best_ast->packet_size);
1042 
1043  avi->stream_index= best_stream_index;
1044  if(!best_ast->remaining)
1045  best_ast->packet_size=
1046  best_ast->remaining= best_st->index_entries[i].size;
1047  }
1048  }
1049 
1050 resync:
1051  if(avi->stream_index >= 0){
1052  AVStream *st= s->streams[ avi->stream_index ];
1053  AVIStream *ast= st->priv_data;
1054  int size, err;
1055 
1056  if(get_subtitle_pkt(s, st, pkt))
1057  return 0;
1058 
1059  if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
1060  size= INT_MAX;
1061  else if(ast->sample_size < 32)
1062  // arbitrary multiplier to avoid tiny packets for raw PCM data
1063  size= 1024*ast->sample_size;
1064  else
1065  size= ast->sample_size;
1066 
1067  if(size > ast->remaining)
1068  size= ast->remaining;
1069  avi->last_pkt_pos= avio_tell(pb);
1070  err= av_get_packet(pb, pkt, size);
1071  if(err<0)
1072  return err;
1073 
1074  if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){
1075  uint8_t *pal;
1076  pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
1077  if(!pal){
1078  av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");
1079  }else{
1080  memcpy(pal, ast->pal, AVPALETTE_SIZE);
1081  ast->has_pal = 0;
1082  }
1083  }
1084 
1085  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1086  dstr = pkt->destruct;
1087  size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
1088  pkt->data, pkt->size);
1089  pkt->destruct = dstr;
1090  pkt->flags |= AV_PKT_FLAG_KEY;
1091  if (size < 0)
1092  av_free_packet(pkt);
1093  } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE
1094  && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
1095  ast->frame_offset++;
1096  avi->stream_index = -1;
1097  ast->remaining = 0;
1098  goto resync;
1099  } else {
1100  /* XXX: How to handle B-frames in AVI? */
1101  pkt->dts = ast->frame_offset;
1102 // pkt->dts += ast->start;
1103  if(ast->sample_size)
1104  pkt->dts /= ast->sample_size;
1105  av_dlog(s, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n",
1106  pkt->dts, ast->frame_offset, ast->scale, ast->rate,
1107  ast->sample_size, AV_TIME_BASE, avi->stream_index, size);
1108  pkt->stream_index = avi->stream_index;
1109 
1110  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
1111  AVIndexEntry *e;
1112  int index;
1113  assert(st->index_entries);
1114 
1115  index= av_index_search_timestamp(st, ast->frame_offset, 0);
1116  e= &st->index_entries[index];
1117 
1118  if(index >= 0 && e->timestamp == ast->frame_offset){
1119  if (e->flags & AVINDEX_KEYFRAME)
1120  pkt->flags |= AV_PKT_FLAG_KEY;
1121  }
1122  } else {
1123  pkt->flags |= AV_PKT_FLAG_KEY;
1124  }
1125  ast->frame_offset += get_duration(ast, pkt->size);
1126  }
1127  ast->remaining -= err;
1128  if(!ast->remaining){
1129  avi->stream_index= -1;
1130  ast->packet_size= 0;
1131  }
1132 
1133  return 0;
1134  }
1135 
1136  if ((err = avi_sync(s, 0)) < 0)
1137  return err;
1138  goto resync;
1139 }
1140 
1141 /* XXX: We make the implicit supposition that the positions are sorted
1142  for each stream. */
1143 static int avi_read_idx1(AVFormatContext *s, int size)
1144 {
1145  AVIContext *avi = s->priv_data;
1146  AVIOContext *pb = s->pb;
1147  int nb_index_entries, i;
1148  AVStream *st;
1149  AVIStream *ast;
1150  unsigned int index, tag, flags, pos, len, first_packet = 1;
1151  unsigned last_pos= -1;
1152  int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
1153 
1154  nb_index_entries = size / 16;
1155  if (nb_index_entries <= 0)
1156  return -1;
1157 
1158  idx1_pos = avio_tell(pb);
1159  avio_seek(pb, avi->movi_list+4, SEEK_SET);
1160  if (avi_sync(s, 1) == 0) {
1161  first_packet_pos = avio_tell(pb) - 8;
1162  }
1163  avi->stream_index = -1;
1164  avio_seek(pb, idx1_pos, SEEK_SET);
1165 
1166  /* Read the entries and sort them in each stream component. */
1167  for(i = 0; i < nb_index_entries; i++) {
1168  tag = avio_rl32(pb);
1169  flags = avio_rl32(pb);
1170  pos = avio_rl32(pb);
1171  len = avio_rl32(pb);
1172  av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
1173  i, tag, flags, pos, len);
1174 
1175  index = ((tag & 0xff) - '0') * 10;
1176  index += ((tag >> 8) & 0xff) - '0';
1177  if (index >= s->nb_streams)
1178  continue;
1179  st = s->streams[index];
1180  ast = st->priv_data;
1181 
1182  if(first_packet && first_packet_pos && len) {
1183  data_offset = first_packet_pos - pos;
1184  first_packet = 0;
1185  }
1186  pos += data_offset;
1187 
1188  av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
1189 
1190  if(pb->eof_reached)
1191  return -1;
1192 
1193  if(last_pos == pos)
1194  avi->non_interleaved= 1;
1195  else if(len || !ast->sample_size)
1196  av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
1197  ast->cum_len += get_duration(ast, len);
1198  last_pos= pos;
1199  }
1200  return 0;
1201 }
1202 
1204  int i;
1205  int64_t last_start=0;
1206  int64_t first_end= INT64_MAX;
1207  int64_t oldpos= avio_tell(s->pb);
1208 
1209  for(i=0; i<s->nb_streams; i++){
1210  AVStream *st = s->streams[i];
1211  int n= st->nb_index_entries;
1212  unsigned int size;
1213 
1214  if(n <= 0)
1215  continue;
1216 
1217  if(n >= 2){
1218  int64_t pos= st->index_entries[0].pos;
1219  avio_seek(s->pb, pos + 4, SEEK_SET);
1220  size= avio_rl32(s->pb);
1221  if(pos + size > st->index_entries[1].pos)
1222  last_start= INT64_MAX;
1223  }
1224 
1225  if(st->index_entries[0].pos > last_start)
1226  last_start= st->index_entries[0].pos;
1227  if(st->index_entries[n-1].pos < first_end)
1228  first_end= st->index_entries[n-1].pos;
1229  }
1230  avio_seek(s->pb, oldpos, SEEK_SET);
1231  return last_start > first_end;
1232 }
1233 
1235 {
1236  AVIContext *avi = s->priv_data;
1237  AVIOContext *pb = s->pb;
1238  uint32_t tag, size;
1239  int64_t pos= avio_tell(pb);
1240  int ret = -1;
1241 
1242  if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
1243  goto the_end; // maybe truncated file
1244  av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
1245  for(;;) {
1246  if (pb->eof_reached)
1247  break;
1248  tag = avio_rl32(pb);
1249  size = avio_rl32(pb);
1250  av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
1251  tag & 0xff,
1252  (tag >> 8) & 0xff,
1253  (tag >> 16) & 0xff,
1254  (tag >> 24) & 0xff,
1255  size);
1256 
1257  if (tag == MKTAG('i', 'd', 'x', '1') &&
1258  avi_read_idx1(s, size) >= 0) {
1259  ret = 0;
1260  break;
1261  }
1262 
1263  size += (size & 1);
1264  if (avio_skip(pb, size) < 0)
1265  break; // something is wrong here
1266  }
1267  the_end:
1268  avio_seek(pb, pos, SEEK_SET);
1269  return ret;
1270 }
1271 
1272 static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
1273 {
1274  AVIStream *ast2 = st2->priv_data;
1275  int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
1276  av_free_packet(&ast2->sub_pkt);
1277  if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
1278  avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
1279  ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
1280 }
1281 
1282 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
1283 {
1284  AVIContext *avi = s->priv_data;
1285  AVStream *st;
1286  int i, index;
1287  int64_t pos;
1288  AVIStream *ast;
1289 
1290  if (!avi->index_loaded) {
1291  /* we only load the index on demand */
1292  avi_load_index(s);
1293  avi->index_loaded = 1;
1294  }
1295  assert(stream_index>= 0);
1296 
1297  st = s->streams[stream_index];
1298  ast= st->priv_data;
1299  index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);
1300  if(index<0)
1301  return -1;
1302 
1303  /* find the position */
1304  pos = st->index_entries[index].pos;
1305  timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
1306 
1307  av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",
1308  timestamp, index, st->index_entries[index].timestamp);
1309 
1310  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1311  /* One and only one real stream for DV in AVI, and it has video */
1312  /* offsets. Calling with other stream indexes should have failed */
1313  /* the av_index_search_timestamp call above. */
1314  assert(stream_index == 0);
1315 
1316  /* Feed the DV video stream version of the timestamp to the */
1317  /* DV demux so it can synthesize correct timestamps. */
1318  ff_dv_offset_reset(avi->dv_demux, timestamp);
1319 
1320  avio_seek(s->pb, pos, SEEK_SET);
1321  avi->stream_index= -1;
1322  return 0;
1323  }
1324 
1325  for(i = 0; i < s->nb_streams; i++) {
1326  AVStream *st2 = s->streams[i];
1327  AVIStream *ast2 = st2->priv_data;
1328 
1329  ast2->packet_size=
1330  ast2->remaining= 0;
1331 
1332  if (ast2->sub_ctx) {
1333  seek_subtitle(st, st2, timestamp);
1334  continue;
1335  }
1336 
1337  if (st2->nb_index_entries <= 0)
1338  continue;
1339 
1340 // assert(st2->codec->block_align);
1341  assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
1342  index = av_index_search_timestamp(
1343  st2,
1344  av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1345  flags | AVSEEK_FLAG_BACKWARD);
1346  if(index<0)
1347  index=0;
1348 
1349  if(!avi->non_interleaved){
1350  while(index>0 && st2->index_entries[index].pos > pos)
1351  index--;
1352  while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
1353  index++;
1354  }
1355 
1356  av_dlog(s, "%"PRId64" %d %"PRId64"\n",
1357  timestamp, index, st2->index_entries[index].timestamp);
1358  /* extract the current frame number */
1359  ast2->frame_offset = st2->index_entries[index].timestamp;
1360  }
1361 
1362  /* do the seek */
1363  avio_seek(s->pb, pos, SEEK_SET);
1364  avi->stream_index= -1;
1365  return 0;
1366 }
1367 
1369 {
1370  int i;
1371  AVIContext *avi = s->priv_data;
1372 
1373  for(i=0;i<s->nb_streams;i++) {
1374  AVStream *st = s->streams[i];
1375  AVIStream *ast = st->priv_data;
1376  if (ast) {
1377  if (ast->sub_ctx) {
1378  av_freep(&ast->sub_ctx->pb);
1380  }
1381  av_free(ast->sub_buffer);
1382  av_free_packet(&ast->sub_pkt);
1383  }
1384  }
1385 
1386  av_free(avi->dv_demux);
1387 
1388  return 0;
1389 }
1390 
1391 static int avi_probe(AVProbeData *p)
1392 {
1393  int i;
1394 
1395  /* check file header */
1396  for(i=0; avi_headers[i][0]; i++)
1397  if(!memcmp(p->buf , avi_headers[i] , 4) &&
1398  !memcmp(p->buf+8, avi_headers[i]+4, 4))
1399  return AVPROBE_SCORE_MAX;
1400 
1401  return 0;
1402 }
1403 
1405  .name = "avi",
1406  .long_name = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),
1407  .priv_data_size = sizeof(AVIContext),
1408  .read_probe = avi_probe,
1413 };