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  int scale;
43  int 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 
56  uint8_t *sub_buffer;
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 
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_log(s, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
517 
518  switch(tag1) {
519  case MKTAG('v', 'i', 'd', 's'):
520  codec_type = AVMEDIA_TYPE_VIDEO;
521 
522  ast->sample_size = 0;
523  break;
524  case MKTAG('a', 'u', 'd', 's'):
525  codec_type = AVMEDIA_TYPE_AUDIO;
526  break;
527  case MKTAG('t', 'x', 't', 's'):
528  codec_type = AVMEDIA_TYPE_SUBTITLE;
529  break;
530  case MKTAG('d', 'a', 't', 's'):
531  codec_type = AVMEDIA_TYPE_DATA;
532  break;
533  default:
534  av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
535  goto fail;
536  }
537  if(ast->sample_size == 0)
538  st->duration = st->nb_frames;
539  ast->frame_offset= ast->cum_len;
540  avio_skip(pb, size - 12 * 4);
541  break;
542  case MKTAG('s', 't', 'r', 'f'):
543  /* stream header */
544  if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
545  avio_skip(pb, size);
546  } else {
547  uint64_t cur_pos = avio_tell(pb);
548  if (cur_pos < list_end)
549  size = FFMIN(size, list_end - cur_pos);
550  st = s->streams[stream_index];
551  switch(codec_type) {
552  case AVMEDIA_TYPE_VIDEO:
553  if(amv_file_format){
554  st->codec->width=avih_width;
555  st->codec->height=avih_height;
557  st->codec->codec_id = CODEC_ID_AMV;
558  avio_skip(pb, size);
559  break;
560  }
561  tag1 = ff_get_bmp_header(pb, st);
562 
563  if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {
565  st->codec->codec_tag = tag1;
567  break;
568  }
569 
570  if(size > 10*4 && size<(1<<30)){
571  st->codec->extradata_size= size - 10*4;
573  if (!st->codec->extradata) {
574  st->codec->extradata_size= 0;
575  return AVERROR(ENOMEM);
576  }
577  avio_read(pb, st->codec->extradata, st->codec->extradata_size);
578  }
579 
580  if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
581  avio_r8(pb);
582 
583  /* Extract palette from extradata if bpp <= 8. */
584  /* This code assumes that extradata contains only palette. */
585  /* This is true for all paletted codecs implemented in Libav. */
586  if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
587  int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
588  const uint8_t *pal_src;
589 
590  pal_size = FFMIN(pal_size, st->codec->extradata_size);
591  pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;
592 #if HAVE_BIGENDIAN
593  for (i = 0; i < pal_size/4; i++)
594  ast->pal[i] = av_bswap32(((uint32_t*)pal_src)[i]);
595 #else
596  memcpy(ast->pal, pal_src, pal_size);
597 #endif
598  ast->has_pal = 1;
599  }
600 
601  print_tag("video", tag1, 0);
602 
604  st->codec->codec_tag = tag1;
606  st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
607  // Support "Resolution 1:1" for Avid AVI Codec
608  if(tag1 == MKTAG('A', 'V', 'R', 'n') &&
609  st->codec->extradata_size >= 31 &&
610  !memcmp(&st->codec->extradata[28], "1:1", 3))
612 
613  if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
614  st->codec->extradata_size+= 9;
616  if(st->codec->extradata)
617  memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
618  }
619  st->codec->height= FFABS(st->codec->height);
620 
621 // avio_skip(pb, size - 5 * 4);
622  break;
623  case AVMEDIA_TYPE_AUDIO:
624  ret = ff_get_wav_header(pb, st->codec, size);
625  if (ret < 0)
626  return ret;
628  if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
629  av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
630  ast->sample_size= st->codec->block_align;
631  }
632  if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
633  avio_skip(pb, 1);
634  /* Force parsing as several audio frames can be in
635  * one packet and timestamps refer to packet start. */
637  /* ADTS header is in extradata, AAC without header must be
638  * stored as exact frames. Parser not needed and it will
639  * fail. */
640  if (st->codec->codec_id == CODEC_ID_AAC && st->codec->extradata_size)
642  /* AVI files with Xan DPCM audio (wrongly) declare PCM
643  * audio in the header but have Axan as stream_code_tag. */
644  if (st->codec->stream_codec_tag == AV_RL32("Axan")){
646  st->codec->codec_tag = 0;
647  }
648  if (amv_file_format){
650  ast->dshow_block_align = 0;
651  }
652  break;
656  break;
657  default:
660  st->codec->codec_tag= 0;
661  avio_skip(pb, size);
662  break;
663  }
664  }
665  break;
666  case MKTAG('i', 'n', 'd', 'x'):
667  i= avio_tell(pb);
668  if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) &&
669  read_braindead_odml_indx(s, 0) < 0 &&
671  goto fail;
672  avio_seek(pb, i+size, SEEK_SET);
673  break;
674  case MKTAG('v', 'p', 'r', 'p'):
675  if(stream_index < (unsigned)s->nb_streams && size > 9*4){
676  AVRational active, active_aspect;
677 
678  st = s->streams[stream_index];
679  avio_rl32(pb);
680  avio_rl32(pb);
681  avio_rl32(pb);
682  avio_rl32(pb);
683  avio_rl32(pb);
684 
685  active_aspect.den= avio_rl16(pb);
686  active_aspect.num= avio_rl16(pb);
687  active.num = avio_rl32(pb);
688  active.den = avio_rl32(pb);
689  avio_rl32(pb); //nbFieldsPerFrame
690 
691  if(active_aspect.num && active_aspect.den && active.num && active.den){
692  st->sample_aspect_ratio= av_div_q(active_aspect, active);
693 //av_log(s, AV_LOG_ERROR, "vprp %d/%d %d/%d\n", active_aspect.num, active_aspect.den, active.num, active.den);
694  }
695  size -= 9*4;
696  }
697  avio_skip(pb, size);
698  break;
699  case MKTAG('s', 't', 'r', 'n'):
700  if(s->nb_streams){
701  avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);
702  break;
703  }
704  default:
705  if(size > 1000000){
706  av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
707  "I will ignore it and try to continue anyway.\n");
709  goto fail;
710  avi->movi_list = avio_tell(pb) - 4;
711  avi->movi_end = avio_size(pb);
712  goto end_of_header;
713  }
714  /* skip tag */
715  size += (size & 1);
716  avio_skip(pb, size);
717  break;
718  }
719  }
720  end_of_header:
721  /* check stream number */
722  if (stream_index != s->nb_streams - 1) {
723  fail:
724  return -1;
725  }
726 
727  if(!avi->index_loaded && pb->seekable)
728  avi_load_index(s);
729  avi->index_loaded = 1;
730 
731  if ((ret = guess_ni_flag(s)) < 0)
732  return ret;
733 
734  avi->non_interleaved |= ret;
735  for(i=0; i<s->nb_streams; i++){
736  AVStream *st = s->streams[i];
737  if(st->nb_index_entries)
738  break;
739  }
740  if(i==s->nb_streams && avi->non_interleaved) {
741  av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");
742  avi->non_interleaved=0;
743  }
744 
745  if(avi->non_interleaved) {
746  av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
747  clean_index(s);
748  }
749 
750  ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
752 
753  return 0;
754 }
755 
756 static int read_gab2_sub(AVStream *st, AVPacket *pkt)
757 {
758  if (pkt->size >= 7 &&
759  !strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data + 5) == 2) {
760  uint8_t desc[256];
761  int score = AVPROBE_SCORE_MAX / 2, ret;
762  AVIStream *ast = st->priv_data;
763  AVInputFormat *sub_demuxer;
764  AVRational time_base;
765  AVIOContext *pb = avio_alloc_context( pkt->data + 7,
766  pkt->size - 7,
767  0, NULL, NULL, NULL, NULL);
768  AVProbeData pd;
769  unsigned int desc_len = avio_rl32(pb);
770 
771  if (desc_len > pb->buf_end - pb->buf_ptr)
772  goto error;
773 
774  ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
775  avio_skip(pb, desc_len - ret);
776  if (*desc)
777  av_dict_set(&st->metadata, "title", desc, 0);
778 
779  avio_rl16(pb); /* flags? */
780  avio_rl32(pb); /* data size */
781 
782  pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };
783  if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
784  goto error;
785 
786  if (!(ast->sub_ctx = avformat_alloc_context()))
787  goto error;
788 
789  ast->sub_ctx->pb = pb;
790  if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
791  av_read_packet(ast->sub_ctx, &ast->sub_pkt);
792  *st->codec = *ast->sub_ctx->streams[0]->codec;
793  ast->sub_ctx->streams[0]->codec->extradata = NULL;
794  time_base = ast->sub_ctx->streams[0]->time_base;
795  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
796  }
797  ast->sub_buffer = pkt->data;
798  memset(pkt, 0, sizeof(*pkt));
799  return 1;
800 error:
801  av_freep(&pb);
802  }
803  return 0;
804 }
805 
807  AVPacket *pkt)
808 {
809  AVIStream *ast, *next_ast = next_st->priv_data;
810  int64_t ts, next_ts, ts_min = INT64_MAX;
811  AVStream *st, *sub_st = NULL;
812  int i;
813 
814  next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
816 
817  for (i=0; i<s->nb_streams; i++) {
818  st = s->streams[i];
819  ast = st->priv_data;
820  if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
822  if (ts <= next_ts && ts < ts_min) {
823  ts_min = ts;
824  sub_st = st;
825  }
826  }
827  }
828 
829  if (sub_st) {
830  ast = sub_st->priv_data;
831  *pkt = ast->sub_pkt;
832  pkt->stream_index = sub_st->index;
833  if (av_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
834  ast->sub_pkt.data = NULL;
835  }
836  return sub_st;
837 }
838 
839 static int get_stream_idx(int *d){
840  if( d[0] >= '0' && d[0] <= '9'
841  && d[1] >= '0' && d[1] <= '9'){
842  return (d[0] - '0') * 10 + (d[1] - '0');
843  }else{
844  return 100; //invalid stream ID
845  }
846 }
847 
848 static int avi_sync(AVFormatContext *s, int exit_early)
849 {
850  AVIContext *avi = s->priv_data;
851  AVIOContext *pb = s->pb;
852  int n;
853  unsigned int d[8];
854  unsigned int size;
855  int64_t i, sync;
856 
857 start_sync:
858  memset(d, -1, sizeof(d));
859  for(i=sync=avio_tell(pb); !pb->eof_reached; i++) {
860  int j;
861 
862  for(j=0; j<7; j++)
863  d[j]= d[j+1];
864  d[7]= avio_r8(pb);
865 
866  size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
867 
868  n= get_stream_idx(d+2);
869 //av_log(s, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %"PRId64" %d %d\n", 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 //av_log(s, AV_LOG_DEBUG, "SKIP\n");
880  goto start_sync;
881  }
882 
883  //parse stray LIST
884  if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){
885  avio_skip(pb, 4);
886  goto start_sync;
887  }
888 
889  n = avi->dv_demux ? 0 : get_stream_idx(d);
890 
891  if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
892  continue;
893 
894  //detect ##ix chunk and skip
895  if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){
896  avio_skip(pb, size);
897  goto start_sync;
898  }
899 
900  //parse ##dc/##wb
901  if(n < s->nb_streams){
902  AVStream *st;
903  AVIStream *ast;
904  st = s->streams[n];
905  ast = st->priv_data;
906 
907  if(s->nb_streams>=2){
908  AVStream *st1 = s->streams[1];
909  AVIStream *ast1= st1->priv_data;
910  //workaround for broken small-file-bug402.avi
911  if( d[2] == 'w' && d[3] == 'b'
912  && n==0
913  && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
915  && ast->prefix == 'd'*256+'c'
916  && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
917  ){
918  n=1;
919  st = st1;
920  ast = ast1;
921  av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
922  }
923  }
924 
925 
926  if (!avi->dv_demux &&
927  ((st->discard >= AVDISCARD_DEFAULT && size==0) /* ||
928  //FIXME needs a little reordering
929  (st->discard >= AVDISCARD_NONKEY &&
930  !(pkt->flags & AV_PKT_FLAG_KEY)) */
931  || st->discard >= AVDISCARD_ALL)) {
932  if (!exit_early) {
933  ast->frame_offset += get_duration(ast, size);
934  }
935  avio_skip(pb, size);
936  goto start_sync;
937  }
938 
939  if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
940  int k = avio_r8(pb);
941  int last = (k + avio_r8(pb) - 1) & 0xFF;
942 
943  avio_rl16(pb); //flags
944 
945  for (; k <= last; k++)
946  ast->pal[k] = avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);
947  ast->has_pal= 1;
948  goto start_sync;
949  } else if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
950  d[2]*256+d[3] == ast->prefix /*||
951  (d[2] == 'd' && d[3] == 'c') ||
952  (d[2] == 'w' && d[3] == 'b')*/) {
953 
954  if (exit_early)
955  return 0;
956 //av_log(s, AV_LOG_DEBUG, "OK\n");
957  if(d[2]*256+d[3] == ast->prefix)
958  ast->prefix_count++;
959  else{
960  ast->prefix= d[2]*256+d[3];
961  ast->prefix_count= 0;
962  }
963 
964  avi->stream_index= n;
965  ast->packet_size= size + 8;
966  ast->remaining= size;
967 
968  if(size || !ast->sample_size){
969  uint64_t pos= avio_tell(pb) - 8;
970  if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
971  av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);
972  }
973  }
974  return 0;
975  }
976  }
977  }
978 
979  return AVERROR_EOF;
980 }
981 
983 {
984  AVIContext *avi = s->priv_data;
985  AVIOContext *pb = s->pb;
986  int err;
987  void* dstr;
988 
989  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
990  int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
991  if (size >= 0)
992  return size;
993  else
994  goto resync;
995  }
996 
997  if(avi->non_interleaved){
998  int best_stream_index = 0;
999  AVStream *best_st= NULL;
1000  AVIStream *best_ast;
1001  int64_t best_ts= INT64_MAX;
1002  int i;
1003 
1004  for(i=0; i<s->nb_streams; i++){
1005  AVStream *st = s->streams[i];
1006  AVIStream *ast = st->priv_data;
1007  int64_t ts= ast->frame_offset;
1008  int64_t last_ts;
1009 
1010  if(!st->nb_index_entries)
1011  continue;
1012 
1013  last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
1014  if(!ast->remaining && ts > last_ts)
1015  continue;
1016 
1017  ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});
1018 
1019 // av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
1020  if(ts < best_ts){
1021  best_ts= ts;
1022  best_st= st;
1023  best_stream_index= i;
1024  }
1025  }
1026  if(!best_st)
1027  return -1;
1028 
1029  best_ast = best_st->priv_data;
1030  best_ts = av_rescale_q(best_ts, (AVRational){FFMAX(1, best_ast->sample_size), AV_TIME_BASE}, best_st->time_base);
1031  if(best_ast->remaining)
1033  else{
1034  i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
1035  if(i>=0)
1036  best_ast->frame_offset= best_st->index_entries[i].timestamp;
1037  }
1038 
1039 // av_log(s, AV_LOG_DEBUG, "%d\n", i);
1040  if(i>=0){
1041  int64_t pos= best_st->index_entries[i].pos;
1042  pos += best_ast->packet_size - best_ast->remaining;
1043  avio_seek(s->pb, pos + 8, SEEK_SET);
1044 // av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);
1045 
1046  assert(best_ast->remaining <= best_ast->packet_size);
1047 
1048  avi->stream_index= best_stream_index;
1049  if(!best_ast->remaining)
1050  best_ast->packet_size=
1051  best_ast->remaining= best_st->index_entries[i].size;
1052  }
1053  }
1054 
1055 resync:
1056  if(avi->stream_index >= 0){
1057  AVStream *st= s->streams[ avi->stream_index ];
1058  AVIStream *ast= st->priv_data;
1059  int size, err;
1060 
1061  if(get_subtitle_pkt(s, st, pkt))
1062  return 0;
1063 
1064  if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
1065  size= INT_MAX;
1066  else if(ast->sample_size < 32)
1067  // arbitrary multiplier to avoid tiny packets for raw PCM data
1068  size= 1024*ast->sample_size;
1069  else
1070  size= ast->sample_size;
1071 
1072  if(size > ast->remaining)
1073  size= ast->remaining;
1074  avi->last_pkt_pos= avio_tell(pb);
1075  err= av_get_packet(pb, pkt, size);
1076  if(err<0)
1077  return err;
1078 
1079  if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){
1080  uint8_t *pal;
1082  if(!pal){
1083  av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");
1084  }else{
1085  memcpy(pal, ast->pal, AVPALETTE_SIZE);
1086  ast->has_pal = 0;
1087  }
1088  }
1089 
1090  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1091  dstr = pkt->destruct;
1092  size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
1093  pkt->data, pkt->size);
1094  pkt->destruct = dstr;
1095  pkt->flags |= AV_PKT_FLAG_KEY;
1096  if (size < 0)
1097  av_free_packet(pkt);
1098  } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE
1099  && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
1100  ast->frame_offset++;
1101  avi->stream_index = -1;
1102  ast->remaining = 0;
1103  goto resync;
1104  } else {
1105  /* XXX: How to handle B-frames in AVI? */
1106  pkt->dts = ast->frame_offset;
1107 // pkt->dts += ast->start;
1108  if(ast->sample_size)
1109  pkt->dts /= ast->sample_size;
1110 //av_log(s, AV_LOG_DEBUG, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, avi->stream_index, size);
1111  pkt->stream_index = avi->stream_index;
1112 
1113  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
1114  AVIndexEntry *e;
1115  int index;
1116  assert(st->index_entries);
1117 
1118  index= av_index_search_timestamp(st, ast->frame_offset, 0);
1119  e= &st->index_entries[index];
1120 
1121  if(index >= 0 && e->timestamp == ast->frame_offset){
1122  if (e->flags & AVINDEX_KEYFRAME)
1123  pkt->flags |= AV_PKT_FLAG_KEY;
1124  }
1125  } else {
1126  pkt->flags |= AV_PKT_FLAG_KEY;
1127  }
1128  ast->frame_offset += get_duration(ast, pkt->size);
1129  }
1130  ast->remaining -= err;
1131  if(!ast->remaining){
1132  avi->stream_index= -1;
1133  ast->packet_size= 0;
1134  }
1135 
1136  return 0;
1137  }
1138 
1139  if ((err = avi_sync(s, 0)) < 0)
1140  return err;
1141  goto resync;
1142 }
1143 
1144 /* XXX: We make the implicit supposition that the positions are sorted
1145  for each stream. */
1146 static int avi_read_idx1(AVFormatContext *s, int size)
1147 {
1148  AVIContext *avi = s->priv_data;
1149  AVIOContext *pb = s->pb;
1150  int nb_index_entries, i;
1151  AVStream *st;
1152  AVIStream *ast;
1153  unsigned int index, tag, flags, pos, len, first_packet = 1;
1154  unsigned last_pos= -1;
1155  int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
1156 
1157  nb_index_entries = size / 16;
1158  if (nb_index_entries <= 0)
1159  return -1;
1160 
1161  idx1_pos = avio_tell(pb);
1162  avio_seek(pb, avi->movi_list+4, SEEK_SET);
1163  if (avi_sync(s, 1) == 0) {
1164  first_packet_pos = avio_tell(pb) - 8;
1165  }
1166  avi->stream_index = -1;
1167  avio_seek(pb, idx1_pos, SEEK_SET);
1168 
1169  /* Read the entries and sort them in each stream component. */
1170  for(i = 0; i < nb_index_entries; i++) {
1171  tag = avio_rl32(pb);
1172  flags = avio_rl32(pb);
1173  pos = avio_rl32(pb);
1174  len = avio_rl32(pb);
1175  av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
1176  i, tag, flags, pos, len);
1177 
1178  index = ((tag & 0xff) - '0') * 10;
1179  index += ((tag >> 8) & 0xff) - '0';
1180  if (index >= s->nb_streams)
1181  continue;
1182  st = s->streams[index];
1183  ast = st->priv_data;
1184 
1185  if(first_packet && first_packet_pos && len) {
1186  data_offset = first_packet_pos - pos;
1187  first_packet = 0;
1188  }
1189  pos += data_offset;
1190 
1191  av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
1192 
1193  if(pb->eof_reached)
1194  return -1;
1195 
1196  if(last_pos == pos)
1197  avi->non_interleaved= 1;
1198  else if(len || !ast->sample_size)
1199  av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
1200  ast->cum_len += get_duration(ast, len);
1201  last_pos= pos;
1202  }
1203  return 0;
1204 }
1205 
1206 /* Scan the index and consider any file with streams more than
1207  * 2 seconds or 64MB apart non-interleaved. */
1209 {
1210  int64_t min_pos, pos;
1211  int i;
1212  int *idx = av_malloc(s->nb_streams * sizeof(*idx));
1213  if (!idx)
1214  return AVERROR(ENOMEM);
1215  else
1216  memset(idx, 0, s->nb_streams * sizeof(*idx));
1217 
1218  for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {
1219  int64_t max_dts = INT64_MIN / 2;
1220  int64_t min_dts = INT64_MAX / 2;
1221  int64_t max_buffer = 0;
1222 
1223  min_pos = INT64_MAX;
1224 
1225  for (i = 0; i < s->nb_streams; i++) {
1226  AVStream *st = s->streams[i];
1227  AVIStream *ast = st->priv_data;
1228  int n = st->nb_index_entries;
1229  while (idx[i] < n && st->index_entries[idx[i]].pos < pos)
1230  idx[i]++;
1231  if (idx[i] < n) {
1232  int64_t dts;
1233  dts = av_rescale_q(st->index_entries[idx[i]].timestamp /
1234  FFMAX(ast->sample_size, 1),
1235  st->time_base, AV_TIME_BASE_Q);
1236  min_dts = FFMIN(min_dts, dts);
1237  min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
1238  }
1239  }
1240  for (i = 0; i < s->nb_streams; i++) {
1241  AVStream *st = s->streams[i];
1242  AVIStream *ast = st->priv_data;
1243 
1244  if (idx[i] && min_dts != INT64_MAX / 2) {
1245  int64_t dts;
1246  dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /
1247  FFMAX(ast->sample_size, 1),
1248  st->time_base, AV_TIME_BASE_Q);
1249  max_dts = FFMAX(max_dts, dts);
1250  max_buffer = FFMAX(max_buffer,
1251  av_rescale(dts - min_dts,
1252  st->codec->bit_rate,
1253  AV_TIME_BASE));
1254  }
1255  }
1256  if (max_dts - min_dts > 2 * AV_TIME_BASE ||
1257  max_buffer > 1024 * 1024 * 8 * 8) {
1258  av_free(idx);
1259  return 1;
1260  }
1261  }
1262  av_free(idx);
1263  return 0;
1264 }
1265 
1267  int i;
1268  int64_t last_start=0;
1269  int64_t first_end= INT64_MAX;
1270  int64_t oldpos= avio_tell(s->pb);
1271 
1272  for(i=0; i<s->nb_streams; i++){
1273  AVStream *st = s->streams[i];
1274  int n= st->nb_index_entries;
1275  unsigned int size;
1276 
1277  if(n <= 0)
1278  continue;
1279 
1280  if(n >= 2){
1281  int64_t pos= st->index_entries[0].pos;
1282  avio_seek(s->pb, pos + 4, SEEK_SET);
1283  size= avio_rl32(s->pb);
1284  if(pos + size > st->index_entries[1].pos)
1285  last_start= INT64_MAX;
1286  }
1287 
1288  if(st->index_entries[0].pos > last_start)
1289  last_start= st->index_entries[0].pos;
1290  if(st->index_entries[n-1].pos < first_end)
1291  first_end= st->index_entries[n-1].pos;
1292  }
1293  avio_seek(s->pb, oldpos, SEEK_SET);
1294 
1295  if (last_start > first_end)
1296  return 1;
1297 
1298  return check_stream_max_drift(s);
1299 }
1300 
1302 {
1303  AVIContext *avi = s->priv_data;
1304  AVIOContext *pb = s->pb;
1305  uint32_t tag, size;
1306  int64_t pos= avio_tell(pb);
1307  int ret = -1;
1308 
1309  if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
1310  goto the_end; // maybe truncated file
1311  av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
1312  for(;;) {
1313  if (pb->eof_reached)
1314  break;
1315  tag = avio_rl32(pb);
1316  size = avio_rl32(pb);
1317  av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
1318  tag & 0xff,
1319  (tag >> 8) & 0xff,
1320  (tag >> 16) & 0xff,
1321  (tag >> 24) & 0xff,
1322  size);
1323 
1324  if (tag == MKTAG('i', 'd', 'x', '1') &&
1325  avi_read_idx1(s, size) >= 0) {
1326  ret = 0;
1327  break;
1328  }
1329 
1330  size += (size & 1);
1331  if (avio_skip(pb, size) < 0)
1332  break; // something is wrong here
1333  }
1334  the_end:
1335  avio_seek(pb, pos, SEEK_SET);
1336  return ret;
1337 }
1338 
1339 static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
1340 {
1341  AVIStream *ast2 = st2->priv_data;
1342  int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
1343  av_free_packet(&ast2->sub_pkt);
1344  if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
1345  avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
1346  av_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
1347 }
1348 
1349 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
1350 {
1351  AVIContext *avi = s->priv_data;
1352  AVStream *st;
1353  int i, index;
1354  int64_t pos;
1355  AVIStream *ast;
1356 
1357  /* Does not matter which stream is requested dv in avi has the
1358  * stream information in the first video stream.
1359  */
1360  if (avi->dv_demux)
1361  stream_index = 0;
1362 
1363  if (!avi->index_loaded) {
1364  /* we only load the index on demand */
1365  avi_load_index(s);
1366  avi->index_loaded = 1;
1367  }
1368 
1369  st = s->streams[stream_index];
1370  ast= st->priv_data;
1371  index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);
1372  if(index<0)
1373  return -1;
1374 
1375  /* find the position */
1376  pos = st->index_entries[index].pos;
1377  timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
1378 
1379 // av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);
1380 
1381  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1382  /* One and only one real stream for DV in AVI, and it has video */
1383  /* offsets. Calling with other stream indexes should have failed */
1384  /* the av_index_search_timestamp call above. */
1385 
1386  /* Feed the DV video stream version of the timestamp to the */
1387  /* DV demux so it can synthesize correct timestamps. */
1388  dv_offset_reset(avi->dv_demux, timestamp);
1389 
1390  avio_seek(s->pb, pos, SEEK_SET);
1391  avi->stream_index= -1;
1392  return 0;
1393  }
1394 
1395  for(i = 0; i < s->nb_streams; i++) {
1396  AVStream *st2 = s->streams[i];
1397  AVIStream *ast2 = st2->priv_data;
1398 
1399  ast2->packet_size=
1400  ast2->remaining= 0;
1401 
1402  if (ast2->sub_ctx) {
1403  seek_subtitle(st, st2, timestamp);
1404  continue;
1405  }
1406 
1407  if (st2->nb_index_entries <= 0)
1408  continue;
1409 
1410 // assert(st2->codec->block_align);
1411  assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
1412  index = av_index_search_timestamp(
1413  st2,
1414  av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1415  flags | AVSEEK_FLAG_BACKWARD);
1416  if(index<0)
1417  index=0;
1418 
1419  if(!avi->non_interleaved){
1420  while(index>0 && st2->index_entries[index].pos > pos)
1421  index--;
1422  while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
1423  index++;
1424  }
1425 
1426 // av_log(s, AV_LOG_DEBUG, "%"PRId64" %d %"PRId64"\n", timestamp, index, st2->index_entries[index].timestamp);
1427  /* extract the current frame number */
1428  ast2->frame_offset = st2->index_entries[index].timestamp;
1429  }
1430 
1431  /* do the seek */
1432  avio_seek(s->pb, pos, SEEK_SET);
1433  avi->stream_index= -1;
1434  return 0;
1435 }
1436 
1438 {
1439  int i;
1440  AVIContext *avi = s->priv_data;
1441 
1442  for(i=0;i<s->nb_streams;i++) {
1443  AVStream *st = s->streams[i];
1444  AVIStream *ast = st->priv_data;
1445  if (ast) {
1446  if (ast->sub_ctx) {
1447  av_freep(&ast->sub_ctx->pb);
1449  }
1450  av_free(ast->sub_buffer);
1451  av_free_packet(&ast->sub_pkt);
1452  }
1453  }
1454 
1455  av_free(avi->dv_demux);
1456 
1457  return 0;
1458 }
1459 
1460 static int avi_probe(AVProbeData *p)
1461 {
1462  int i;
1463 
1464  /* check file header */
1465  for(i=0; avi_headers[i][0]; i++)
1466  if(!memcmp(p->buf , avi_headers[i] , 4) &&
1467  !memcmp(p->buf+8, avi_headers[i]+4, 4))
1468  return AVPROBE_SCORE_MAX;
1469 
1470  return 0;
1471 }
1472 
1474  .name = "avi",
1475  .long_name = NULL_IF_CONFIG_SMALL("AVI format"),
1476  .priv_data_size = sizeof(AVIContext),
1477  .read_probe = avi_probe,
1482 };