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avidec.c
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1 /*
2  * AVI 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 <inttypes.h>
23 
24 #include "libavutil/avassert.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/bswap.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/dict.h"
29 #include "libavutil/internal.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/mathematics.h"
32 #include "avformat.h"
33 #include "avi.h"
34 #include "dv.h"
35 #include "internal.h"
36 #include "riff.h"
37 #include "libavcodec/bytestream.h"
38 #include "libavcodec/exif.h"
39 
40 typedef struct AVIStream {
41  int64_t frame_offset; /* current frame (video) or byte (audio) counter
42  * (used to compute the pts) */
43  int remaining;
44  int packet_size;
45 
46  uint32_t scale;
47  uint32_t rate;
48  int sample_size; /* size of one sample (or packet)
49  * (in the rate/scale sense) in bytes */
50 
51  int64_t cum_len; /* temporary storage (used during seek) */
52  int prefix; /* normally 'd'<<8 + 'c' or 'w'<<8 + 'b' */
53  int prefix_count;
54  uint32_t pal[256];
55  int has_pal;
56  int dshow_block_align; /* block align variable used to emulate bugs in
57  * the MS dshow demuxer */
58 
59  AVFormatContext *sub_ctx;
60  AVPacket sub_pkt;
61  uint8_t *sub_buffer;
62 
63  int64_t seek_pos;
64 } AVIStream;
65 
66 typedef struct {
67  const AVClass *class;
68  int64_t riff_end;
69  int64_t movi_end;
70  int64_t fsize;
71  int64_t io_fsize;
72  int64_t movi_list;
73  int64_t last_pkt_pos;
74  int index_loaded;
75  int is_odml;
76  int non_interleaved;
77  int stream_index;
78  DVDemuxContext *dv_demux;
79  int odml_depth;
80  int use_odml;
81 #define MAX_ODML_DEPTH 1000
82  int64_t dts_max;
83 } AVIContext;
84 
85 
86 static const AVOption options[] = {
87  { "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.i64 = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},
88  { NULL },
89 };
90 
91 static const AVClass demuxer_class = {
92  .class_name = "avi",
93  .item_name = av_default_item_name,
94  .option = options,
95  .version = LIBAVUTIL_VERSION_INT,
96  .category = AV_CLASS_CATEGORY_DEMUXER,
97 };
98 
99 
100 static const char avi_headers[][8] = {
101  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
102  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
103  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19 },
104  { 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
105  { 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
106  { 0 }
107 };
108 
109 static const AVMetadataConv avi_metadata_conv[] = {
110  { "strn", "title" },
111  { 0 },
112 };
113 
114 static int avi_load_index(AVFormatContext *s);
115 static int guess_ni_flag(AVFormatContext *s);
116 
117 #define print_tag(str, tag, size) \
118  av_dlog(NULL, "pos:%"PRIX64" %s: tag=%c%c%c%c size=0x%x\n", \
119  avio_tell(pb), str, tag & 0xff, \
120  (tag >> 8) & 0xff, \
121  (tag >> 16) & 0xff, \
122  (tag >> 24) & 0xff, \
123  size)
124 
125 static inline int get_duration(AVIStream *ast, int len)
126 {
127  if (ast->sample_size)
128  return len;
129  else if (ast->dshow_block_align)
130  return (len + ast->dshow_block_align - 1) / ast->dshow_block_align;
131  else
132  return 1;
133 }
134 
135 static int get_riff(AVFormatContext *s, AVIOContext *pb)
136 {
137  AVIContext *avi = s->priv_data;
138  char header[8];
139  int i;
140 
141  /* check RIFF header */
142  avio_read(pb, header, 4);
143  avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
144  avi->riff_end += avio_tell(pb); /* RIFF chunk end */
145  avio_read(pb, header + 4, 4);
146 
147  for (i = 0; avi_headers[i][0]; i++)
148  if (!memcmp(header, avi_headers[i], 8))
149  break;
150  if (!avi_headers[i][0])
151  return AVERROR_INVALIDDATA;
152 
153  if (header[7] == 0x19)
154  av_log(s, AV_LOG_INFO,
155  "This file has been generated by a totally broken muxer.\n");
156 
157  return 0;
158 }
159 
160 static int read_braindead_odml_indx(AVFormatContext *s, int frame_num)
161 {
162  AVIContext *avi = s->priv_data;
163  AVIOContext *pb = s->pb;
164  int longs_pre_entry = avio_rl16(pb);
165  int index_sub_type = avio_r8(pb);
166  int index_type = avio_r8(pb);
167  int entries_in_use = avio_rl32(pb);
168  int chunk_id = avio_rl32(pb);
169  int64_t base = avio_rl64(pb);
170  int stream_id = ((chunk_id & 0xFF) - '0') * 10 +
171  ((chunk_id >> 8 & 0xFF) - '0');
172  AVStream *st;
173  AVIStream *ast;
174  int i;
175  int64_t last_pos = -1;
176  int64_t filesize = avi->fsize;
177 
178  av_dlog(s,
179  "longs_pre_entry:%d index_type:%d entries_in_use:%d "
180  "chunk_id:%X base:%16"PRIX64"\n",
181  longs_pre_entry,
182  index_type,
183  entries_in_use,
184  chunk_id,
185  base);
186 
187  if (stream_id >= s->nb_streams || stream_id < 0)
188  return AVERROR_INVALIDDATA;
189  st = s->streams[stream_id];
190  ast = st->priv_data;
191 
192  if (index_sub_type)
193  return AVERROR_INVALIDDATA;
194 
195  avio_rl32(pb);
196 
197  if (index_type && longs_pre_entry != 2)
198  return AVERROR_INVALIDDATA;
199  if (index_type > 1)
200  return AVERROR_INVALIDDATA;
201 
202  if (filesize > 0 && base >= filesize) {
203  av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
204  if (base >> 32 == (base & 0xFFFFFFFF) &&
205  (base & 0xFFFFFFFF) < filesize &&
206  filesize <= 0xFFFFFFFF)
207  base &= 0xFFFFFFFF;
208  else
209  return AVERROR_INVALIDDATA;
210  }
211 
212  for (i = 0; i < entries_in_use; i++) {
213  if (index_type) {
214  int64_t pos = avio_rl32(pb) + base - 8;
215  int len = avio_rl32(pb);
216  int key = len >= 0;
217  len &= 0x7FFFFFFF;
218 
219 #ifdef DEBUG_SEEK
220  av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);
221 #endif
222  if (avio_feof(pb))
223  return AVERROR_INVALIDDATA;
224 
225  if (last_pos == pos || pos == base - 8)
226  avi->non_interleaved = 1;
227  if (last_pos != pos && len)
228  av_add_index_entry(st, pos, ast->cum_len, len, 0,
229  key ? AVINDEX_KEYFRAME : 0);
230 
231  ast->cum_len += get_duration(ast, len);
232  last_pos = pos;
233  } else {
234  int64_t offset, pos;
235  int duration;
236  offset = avio_rl64(pb);
237  avio_rl32(pb); /* size */
238  duration = avio_rl32(pb);
239 
240  if (avio_feof(pb))
241  return AVERROR_INVALIDDATA;
242 
243  pos = avio_tell(pb);
244 
245  if (avi->odml_depth > MAX_ODML_DEPTH) {
246  av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
247  return AVERROR_INVALIDDATA;
248  }
249 
250  if (avio_seek(pb, offset + 8, SEEK_SET) < 0)
251  return -1;
252  avi->odml_depth++;
253  read_braindead_odml_indx(s, frame_num);
254  avi->odml_depth--;
255  frame_num += duration;
256 
257  if (avio_seek(pb, pos, SEEK_SET) < 0) {
258  av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index\n");
259  return -1;
260  }
261 
262  }
263  }
264  avi->index_loaded = 2;
265  return 0;
266 }
267 
268 static void clean_index(AVFormatContext *s)
269 {
270  int i;
271  int64_t j;
272 
273  for (i = 0; i < s->nb_streams; i++) {
274  AVStream *st = s->streams[i];
275  AVIStream *ast = st->priv_data;
276  int n = st->nb_index_entries;
277  int max = ast->sample_size;
278  int64_t pos, size, ts;
279 
280  if (n != 1 || ast->sample_size == 0)
281  continue;
282 
283  while (max < 1024)
284  max += max;
285 
286  pos = st->index_entries[0].pos;
287  size = st->index_entries[0].size;
288  ts = st->index_entries[0].timestamp;
289 
290  for (j = 0; j < size; j += max)
291  av_add_index_entry(st, pos + j, ts + j, FFMIN(max, size - j), 0,
292  AVINDEX_KEYFRAME);
293  }
294 }
295 
296 static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag,
297  uint32_t size)
298 {
299  AVIOContext *pb = s->pb;
300  char key[5] = { 0 };
301  char *value;
302 
303  size += (size & 1);
304 
305  if (size == UINT_MAX)
306  return AVERROR(EINVAL);
307  value = av_malloc(size + 1);
308  if (!value)
309  return AVERROR(ENOMEM);
310  avio_read(pb, value, size);
311  value[size] = 0;
312 
313  AV_WL32(key, tag);
314 
315  return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
316  AV_DICT_DONT_STRDUP_VAL);
317 }
318 
319 static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
320  "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
321 
322 static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
323 {
324  char month[4], time[9], buffer[64];
325  int i, day, year;
326  /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
327  if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
328  month, &day, time, &year) == 4) {
329  for (i = 0; i < 12; i++)
330  if (!av_strcasecmp(month, months[i])) {
331  snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
332  year, i + 1, day, time);
333  av_dict_set(metadata, "creation_time", buffer, 0);
334  }
335  } else if (date[4] == '/' && date[7] == '/') {
336  date[4] = date[7] = '-';
337  av_dict_set(metadata, "creation_time", date, 0);
338  }
339 }
340 
341 static void avi_read_nikon(AVFormatContext *s, uint64_t end)
342 {
343  while (avio_tell(s->pb) < end) {
344  uint32_t tag = avio_rl32(s->pb);
345  uint32_t size = avio_rl32(s->pb);
346  switch (tag) {
347  case MKTAG('n', 'c', 't', 'g'): /* Nikon Tags */
348  {
349  uint64_t tag_end = avio_tell(s->pb) + size;
350  while (avio_tell(s->pb) < tag_end) {
351  uint16_t tag = avio_rl16(s->pb);
352  uint16_t size = avio_rl16(s->pb);
353  const char *name = NULL;
354  char buffer[64] = { 0 };
355  size = FFMIN(size, tag_end - avio_tell(s->pb));
356  size -= avio_read(s->pb, buffer,
357  FFMIN(size, sizeof(buffer) - 1));
358  switch (tag) {
359  case 0x03:
360  name = "maker";
361  break;
362  case 0x04:
363  name = "model";
364  break;
365  case 0x13:
366  name = "creation_time";
367  if (buffer[4] == ':' && buffer[7] == ':')
368  buffer[4] = buffer[7] = '-';
369  break;
370  }
371  if (name)
372  av_dict_set(&s->metadata, name, buffer, 0);
373  avio_skip(s->pb, size);
374  }
375  break;
376  }
377  default:
378  avio_skip(s->pb, size);
379  break;
380  }
381  }
382 }
383 
384 static int avi_extract_stream_metadata(AVStream *st)
385 {
386  GetByteContext gb;
387  uint8_t *data = st->codec->extradata;
388  int data_size = st->codec->extradata_size;
389  int tag, offset;
390 
391  if (!data || data_size < 8) {
392  return AVERROR_INVALIDDATA;
393  }
394 
395  bytestream2_init(&gb, data, data_size);
396 
397  tag = bytestream2_get_le32(&gb);
398 
399  switch (tag) {
400  case MKTAG('A', 'V', 'I', 'F'):
401  // skip 4 byte padding
402  bytestream2_skip(&gb, 4);
403  offset = bytestream2_tell(&gb);
404  bytestream2_init(&gb, data + offset, data_size - offset);
405 
406  // decode EXIF tags from IFD, AVI is always little-endian
407  return avpriv_exif_decode_ifd(st->codec, &gb, 1, 0, &st->metadata);
408  break;
409  case MKTAG('C', 'A', 'S', 'I'):
410  avpriv_request_sample(st->codec, "RIFF stream data tag type CASI (%u)", tag);
411  break;
412  case MKTAG('Z', 'o', 'r', 'a'):
413  avpriv_request_sample(st->codec, "RIFF stream data tag type Zora (%u)", tag);
414  break;
415  default:
416  break;
417  }
418 
419  return 0;
420 }
421 
422 static int calculate_bitrate(AVFormatContext *s)
423 {
424  AVIContext *avi = s->priv_data;
425  int i, j;
426  int64_t lensum = 0;
427  int64_t maxpos = 0;
428 
429  for (i = 0; i<s->nb_streams; i++) {
430  int64_t len = 0;
431  AVStream *st = s->streams[i];
432 
433  if (!st->nb_index_entries)
434  continue;
435 
436  for (j = 0; j < st->nb_index_entries; j++)
437  len += st->index_entries[j].size;
438  maxpos = FFMAX(maxpos, st->index_entries[j-1].pos);
439  lensum += len;
440  }
441  if (maxpos < avi->io_fsize*9/10) // index does not cover the whole file
442  return 0;
443  if (lensum*9/10 > maxpos || lensum < maxpos*9/10) // frame sum and filesize mismatch
444  return 0;
445 
446  for (i = 0; i<s->nb_streams; i++) {
447  int64_t len = 0;
448  AVStream *st = s->streams[i];
449  int64_t duration;
450 
451  for (j = 0; j < st->nb_index_entries; j++)
452  len += st->index_entries[j].size;
453 
454  if (st->nb_index_entries < 2 || st->codec->bit_rate > 0)
455  continue;
456  duration = st->index_entries[j-1].timestamp - st->index_entries[0].timestamp;
457  st->codec->bit_rate = av_rescale(8*len, st->time_base.den, duration * st->time_base.num);
458  }
459  return 1;
460 }
461 
462 static int avi_read_header(AVFormatContext *s)
463 {
464  AVIContext *avi = s->priv_data;
465  AVIOContext *pb = s->pb;
466  unsigned int tag, tag1, handler;
467  int codec_type, stream_index, frame_period;
468  unsigned int size;
469  int i;
470  AVStream *st;
471  AVIStream *ast = NULL;
472  int avih_width = 0, avih_height = 0;
473  int amv_file_format = 0;
474  uint64_t list_end = 0;
475  int ret;
476  AVDictionaryEntry *dict_entry;
477 
478  avi->stream_index = -1;
479 
480  ret = get_riff(s, pb);
481  if (ret < 0)
482  return ret;
483 
484  av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);
485 
486  avi->io_fsize = avi->fsize = avio_size(pb);
487  if (avi->fsize <= 0 || avi->fsize < avi->riff_end)
488  avi->fsize = avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
489 
490  /* first list tag */
491  stream_index = -1;
492  codec_type = -1;
493  frame_period = 0;
494  for (;;) {
495  if (avio_feof(pb))
496  goto fail;
497  tag = avio_rl32(pb);
498  size = avio_rl32(pb);
499 
500  print_tag("tag", tag, size);
501 
502  switch (tag) {
503  case MKTAG('L', 'I', 'S', 'T'):
504  list_end = avio_tell(pb) + size;
505  /* Ignored, except at start of video packets. */
506  tag1 = avio_rl32(pb);
507 
508  print_tag("list", tag1, 0);
509 
510  if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
511  avi->movi_list = avio_tell(pb) - 4;
512  if (size)
513  avi->movi_end = avi->movi_list + size + (size & 1);
514  else
515  avi->movi_end = avi->fsize;
516  av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
517  goto end_of_header;
518  } else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
519  ff_read_riff_info(s, size - 4);
520  else if (tag1 == MKTAG('n', 'c', 'd', 't'))
521  avi_read_nikon(s, list_end);
522 
523  break;
524  case MKTAG('I', 'D', 'I', 'T'):
525  {
526  unsigned char date[64] = { 0 };
527  size += (size & 1);
528  size -= avio_read(pb, date, FFMIN(size, sizeof(date) - 1));
529  avio_skip(pb, size);
530  avi_metadata_creation_time(&s->metadata, date);
531  break;
532  }
533  case MKTAG('d', 'm', 'l', 'h'):
534  avi->is_odml = 1;
535  avio_skip(pb, size + (size & 1));
536  break;
537  case MKTAG('a', 'm', 'v', 'h'):
538  amv_file_format = 1;
539  case MKTAG('a', 'v', 'i', 'h'):
540  /* AVI header */
541  /* using frame_period is bad idea */
542  frame_period = avio_rl32(pb);
543  avio_rl32(pb); /* max. bytes per second */
544  avio_rl32(pb);
545  avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;
546 
547  avio_skip(pb, 2 * 4);
548  avio_rl32(pb);
549  avio_rl32(pb);
550  avih_width = avio_rl32(pb);
551  avih_height = avio_rl32(pb);
552 
553  avio_skip(pb, size - 10 * 4);
554  break;
555  case MKTAG('s', 't', 'r', 'h'):
556  /* stream header */
557 
558  tag1 = avio_rl32(pb);
559  handler = avio_rl32(pb); /* codec tag */
560 
561  if (tag1 == MKTAG('p', 'a', 'd', 's')) {
562  avio_skip(pb, size - 8);
563  break;
564  } else {
565  stream_index++;
566  st = avformat_new_stream(s, NULL);
567  if (!st)
568  goto fail;
569 
570  st->id = stream_index;
571  ast = av_mallocz(sizeof(AVIStream));
572  if (!ast)
573  goto fail;
574  st->priv_data = ast;
575  }
576  if (amv_file_format)
577  tag1 = stream_index ? MKTAG('a', 'u', 'd', 's')
578  : MKTAG('v', 'i', 'd', 's');
579 
580  print_tag("strh", tag1, -1);
581 
582  if (tag1 == MKTAG('i', 'a', 'v', 's') ||
583  tag1 == MKTAG('i', 'v', 'a', 's')) {
584  int64_t dv_dur;
585 
586  /* After some consideration -- I don't think we
587  * have to support anything but DV in type1 AVIs. */
588  if (s->nb_streams != 1)
589  goto fail;
590 
591  if (handler != MKTAG('d', 'v', 's', 'd') &&
592  handler != MKTAG('d', 'v', 'h', 'd') &&
593  handler != MKTAG('d', 'v', 's', 'l'))
594  goto fail;
595 
596  ast = s->streams[0]->priv_data;
597  av_freep(&s->streams[0]->codec->extradata);
598  av_freep(&s->streams[0]->codec);
599  if (s->streams[0]->info)
600  av_freep(&s->streams[0]->info->duration_error);
601  av_freep(&s->streams[0]->info);
602  av_freep(&s->streams[0]);
603  s->nb_streams = 0;
604  if (CONFIG_DV_DEMUXER) {
605  avi->dv_demux = avpriv_dv_init_demux(s);
606  if (!avi->dv_demux)
607  goto fail;
608  } else
609  goto fail;
610  s->streams[0]->priv_data = ast;
611  avio_skip(pb, 3 * 4);
612  ast->scale = avio_rl32(pb);
613  ast->rate = avio_rl32(pb);
614  avio_skip(pb, 4); /* start time */
615 
616  dv_dur = avio_rl32(pb);
617  if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
618  dv_dur *= AV_TIME_BASE;
619  s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
620  }
621  /* else, leave duration alone; timing estimation in utils.c
622  * will make a guess based on bitrate. */
623 
624  stream_index = s->nb_streams - 1;
625  avio_skip(pb, size - 9 * 4);
626  break;
627  }
628 
629  av_assert0(stream_index < s->nb_streams);
630  st->codec->stream_codec_tag = handler;
631 
632  avio_rl32(pb); /* flags */
633  avio_rl16(pb); /* priority */
634  avio_rl16(pb); /* language */
635  avio_rl32(pb); /* initial frame */
636  ast->scale = avio_rl32(pb);
637  ast->rate = avio_rl32(pb);
638  if (!(ast->scale && ast->rate)) {
639  av_log(s, AV_LOG_WARNING,
640  "scale/rate is %"PRIu32"/%"PRIu32" which is invalid. "
641  "(This file has been generated by broken software.)\n",
642  ast->scale,
643  ast->rate);
644  if (frame_period) {
645  ast->rate = 1000000;
646  ast->scale = frame_period;
647  } else {
648  ast->rate = 25;
649  ast->scale = 1;
650  }
651  }
652  avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
653 
654  ast->cum_len = avio_rl32(pb); /* start */
655  st->nb_frames = avio_rl32(pb);
656 
657  st->start_time = 0;
658  avio_rl32(pb); /* buffer size */
659  avio_rl32(pb); /* quality */
660  if (ast->cum_len*ast->scale/ast->rate > 3600) {
661  av_log(s, AV_LOG_ERROR, "crazy start time, iam scared, giving up\n");
662  return AVERROR_INVALIDDATA;
663  }
664  ast->sample_size = avio_rl32(pb); /* sample ssize */
665  ast->cum_len *= FFMAX(1, ast->sample_size);
666  av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",
667  ast->rate, ast->scale, ast->sample_size);
668 
669  switch (tag1) {
670  case MKTAG('v', 'i', 'd', 's'):
671  codec_type = AVMEDIA_TYPE_VIDEO;
672 
673  ast->sample_size = 0;
674  st->avg_frame_rate = av_inv_q(st->time_base);
675  break;
676  case MKTAG('a', 'u', 'd', 's'):
677  codec_type = AVMEDIA_TYPE_AUDIO;
678  break;
679  case MKTAG('t', 'x', 't', 's'):
680  codec_type = AVMEDIA_TYPE_SUBTITLE;
681  break;
682  case MKTAG('d', 'a', 't', 's'):
683  codec_type = AVMEDIA_TYPE_DATA;
684  break;
685  default:
686  av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);
687  }
688  if (ast->sample_size == 0) {
689  st->duration = st->nb_frames;
690  if (st->duration > 0 && avi->io_fsize > 0 && avi->riff_end > avi->io_fsize) {
691  av_log(s, AV_LOG_DEBUG, "File is truncated adjusting duration\n");
692  st->duration = av_rescale(st->duration, avi->io_fsize, avi->riff_end);
693  }
694  }
695  ast->frame_offset = ast->cum_len;
696  avio_skip(pb, size - 12 * 4);
697  break;
698  case MKTAG('s', 't', 'r', 'f'):
699  /* stream header */
700  if (!size)
701  break;
702  if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
703  avio_skip(pb, size);
704  } else {
705  uint64_t cur_pos = avio_tell(pb);
706  unsigned esize;
707  if (cur_pos < list_end)
708  size = FFMIN(size, list_end - cur_pos);
709  st = s->streams[stream_index];
710  if (st->codec->codec_type != AVMEDIA_TYPE_UNKNOWN) {
711  avio_skip(pb, size);
712  break;
713  }
714  switch (codec_type) {
715  case AVMEDIA_TYPE_VIDEO:
716  if (amv_file_format) {
717  st->codec->width = avih_width;
718  st->codec->height = avih_height;
719  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
720  st->codec->codec_id = AV_CODEC_ID_AMV;
721  avio_skip(pb, size);
722  break;
723  }
724  tag1 = ff_get_bmp_header(pb, st, &esize);
725 
726  if (tag1 == MKTAG('D', 'X', 'S', 'B') ||
727  tag1 == MKTAG('D', 'X', 'S', 'A')) {
728  st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
729  st->codec->codec_tag = tag1;
730  st->codec->codec_id = AV_CODEC_ID_XSUB;
731  break;
732  }
733 
734  if (size > 10 * 4 && size < (1 << 30) && size < avi->fsize) {
735  if (esize == size-1 && (esize&1)) {
736  st->codec->extradata_size = esize - 10 * 4;
737  } else
738  st->codec->extradata_size = size - 10 * 4;
739  if (ff_get_extradata(st->codec, pb, st->codec->extradata_size) < 0)
740  return AVERROR(ENOMEM);
741  }
742 
743  // FIXME: check if the encoder really did this correctly
744  if (st->codec->extradata_size & 1)
745  avio_r8(pb);
746 
747  /* Extract palette from extradata if bpp <= 8.
748  * This code assumes that extradata contains only palette.
749  * This is true for all paletted codecs implemented in
750  * FFmpeg. */
751  if (st->codec->extradata_size &&
752  (st->codec->bits_per_coded_sample <= 8)) {
753  int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
754  const uint8_t *pal_src;
755 
756  pal_size = FFMIN(pal_size, st->codec->extradata_size);
757  pal_src = st->codec->extradata +
758  st->codec->extradata_size - pal_size;
759  for (i = 0; i < pal_size / 4; i++)
760  ast->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i);
761  ast->has_pal = 1;
762  }
763 
764  print_tag("video", tag1, 0);
765 
766  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
767  st->codec->codec_tag = tag1;
768  st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags,
769  tag1);
770  /* This is needed to get the pict type which is necessary
771  * for generating correct pts. */
772  st->need_parsing = AVSTREAM_PARSE_HEADERS;
773  if (st->codec->codec_tag == MKTAG('V', 'S', 'S', 'H'))
774  st->need_parsing = AVSTREAM_PARSE_FULL;
775 
776  if (st->codec->codec_tag == 0 && st->codec->height > 0 &&
777  st->codec->extradata_size < 1U << 30) {
778  st->codec->extradata_size += 9;
779  if ((ret = av_reallocp(&st->codec->extradata,
780  st->codec->extradata_size +
781  FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {
782  st->codec->extradata_size = 0;
783  return ret;
784  } else
785  memcpy(st->codec->extradata + st->codec->extradata_size - 9,
786  "BottomUp", 9);
787  }
788  st->codec->height = FFABS(st->codec->height);
789 
790 // avio_skip(pb, size - 5 * 4);
791  break;
792  case AVMEDIA_TYPE_AUDIO:
793  ret = ff_get_wav_header(pb, st->codec, size);
794  if (ret < 0)
795  return ret;
796  ast->dshow_block_align = st->codec->block_align;
797  if (ast->sample_size && st->codec->block_align &&
798  ast->sample_size != st->codec->block_align) {
799  av_log(s,
800  AV_LOG_WARNING,
801  "sample size (%d) != block align (%d)\n",
802  ast->sample_size,
803  st->codec->block_align);
804  ast->sample_size = st->codec->block_align;
805  }
806  /* 2-aligned
807  * (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
808  if (size & 1)
809  avio_skip(pb, 1);
810  /* Force parsing as several audio frames can be in
811  * one packet and timestamps refer to packet start. */
812  st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;
813  /* ADTS header is in extradata, AAC without header must be
814  * stored as exact frames. Parser not needed and it will
815  * fail. */
816  if (st->codec->codec_id == AV_CODEC_ID_AAC &&
817  st->codec->extradata_size)
818  st->need_parsing = AVSTREAM_PARSE_NONE;
819  /* AVI files with Xan DPCM audio (wrongly) declare PCM
820  * audio in the header but have Axan as stream_code_tag. */
821  if (st->codec->stream_codec_tag == AV_RL32("Axan")) {
822  st->codec->codec_id = AV_CODEC_ID_XAN_DPCM;
823  st->codec->codec_tag = 0;
824  ast->dshow_block_align = 0;
825  }
826  if (amv_file_format) {
827  st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_AMV;
828  ast->dshow_block_align = 0;
829  }
830  if (st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align <= 4 && ast->dshow_block_align) {
831  av_log(s, AV_LOG_DEBUG, "overriding invalid dshow_block_align of %d\n", ast->dshow_block_align);
832  ast->dshow_block_align = 0;
833  }
834  if (st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 1024 && ast->sample_size == 1024 ||
835  st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 4096 && ast->sample_size == 4096 ||
836  st->codec->codec_id == AV_CODEC_ID_MP3 && ast->dshow_block_align == 1152 && ast->sample_size == 1152) {
837  av_log(s, AV_LOG_DEBUG, "overriding sample_size\n");
838  ast->sample_size = 0;
839  }
840  break;
841  case AVMEDIA_TYPE_SUBTITLE:
842  st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
843  st->request_probe= 1;
844  avio_skip(pb, size);
845  break;
846  default:
847  st->codec->codec_type = AVMEDIA_TYPE_DATA;
848  st->codec->codec_id = AV_CODEC_ID_NONE;
849  st->codec->codec_tag = 0;
850  avio_skip(pb, size);
851  break;
852  }
853  }
854  break;
855  case MKTAG('s', 't', 'r', 'd'):
856  if (stream_index >= (unsigned)s->nb_streams
857  || s->streams[stream_index]->codec->extradata_size
858  || s->streams[stream_index]->codec->codec_tag == MKTAG('H','2','6','4')) {
859  avio_skip(pb, size);
860  } else {
861  uint64_t cur_pos = avio_tell(pb);
862  if (cur_pos < list_end)
863  size = FFMIN(size, list_end - cur_pos);
864  st = s->streams[stream_index];
865 
866  if (size<(1<<30)) {
867  if (ff_get_extradata(st->codec, pb, size) < 0)
868  return AVERROR(ENOMEM);
869  }
870 
871  if (st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
872  avio_r8(pb);
873 
874  ret = avi_extract_stream_metadata(st);
875  if (ret < 0) {
876  av_log(s, AV_LOG_WARNING, "could not decoding EXIF data in stream header.\n");
877  }
878  }
879  break;
880  case MKTAG('i', 'n', 'd', 'x'):
881  i = avio_tell(pb);
882  if (pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) &&
883  avi->use_odml &&
884  read_braindead_odml_indx(s, 0) < 0 &&
885  (s->error_recognition & AV_EF_EXPLODE))
886  goto fail;
887  avio_seek(pb, i + size, SEEK_SET);
888  break;
889  case MKTAG('v', 'p', 'r', 'p'):
890  if (stream_index < (unsigned)s->nb_streams && size > 9 * 4) {
891  AVRational active, active_aspect;
892 
893  st = s->streams[stream_index];
894  avio_rl32(pb);
895  avio_rl32(pb);
896  avio_rl32(pb);
897  avio_rl32(pb);
898  avio_rl32(pb);
899 
900  active_aspect.den = avio_rl16(pb);
901  active_aspect.num = avio_rl16(pb);
902  active.num = avio_rl32(pb);
903  active.den = avio_rl32(pb);
904  avio_rl32(pb); // nbFieldsPerFrame
905 
906  if (active_aspect.num && active_aspect.den &&
907  active.num && active.den) {
908  st->sample_aspect_ratio = av_div_q(active_aspect, active);
909  av_dlog(s, "vprp %d/%d %d/%d\n",
910  active_aspect.num, active_aspect.den,
911  active.num, active.den);
912  }
913  size -= 9 * 4;
914  }
915  avio_skip(pb, size);
916  break;
917  case MKTAG('s', 't', 'r', 'n'):
918  if (s->nb_streams) {
919  ret = avi_read_tag(s, s->streams[s->nb_streams - 1], tag, size);
920  if (ret < 0)
921  return ret;
922  break;
923  }
924  default:
925  if (size > 1000000) {
926  av_log(s, AV_LOG_ERROR,
927  "Something went wrong during header parsing, "
928  "I will ignore it and try to continue anyway.\n");
929  if (s->error_recognition & AV_EF_EXPLODE)
930  goto fail;
931  avi->movi_list = avio_tell(pb) - 4;
932  avi->movi_end = avi->fsize;
933  goto end_of_header;
934  }
935  /* skip tag */
936  size += (size & 1);
937  avio_skip(pb, size);
938  break;
939  }
940  }
941 
942 end_of_header:
943  /* check stream number */
944  if (stream_index != s->nb_streams - 1) {
945 
946 fail:
947  return AVERROR_INVALIDDATA;
948  }
949 
950  if (!avi->index_loaded && pb->seekable)
951  avi_load_index(s);
952  calculate_bitrate(s);
953  avi->index_loaded |= 1;
954 
955  if ((ret = guess_ni_flag(s)) < 0)
956  return ret;
957 
958  avi->non_interleaved |= ret | (s->flags & AVFMT_FLAG_SORT_DTS);
959 
960  dict_entry = av_dict_get(s->metadata, "ISFT", NULL, 0);
961  if (dict_entry && !strcmp(dict_entry->value, "PotEncoder"))
962  for (i = 0; i < s->nb_streams; i++) {
963  AVStream *st = s->streams[i];
964  if ( st->codec->codec_id == AV_CODEC_ID_MPEG1VIDEO
965  || st->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
966  st->need_parsing = AVSTREAM_PARSE_FULL;
967  }
968 
969  for (i = 0; i < s->nb_streams; i++) {
970  AVStream *st = s->streams[i];
971  if (st->nb_index_entries)
972  break;
973  }
974  // DV-in-AVI cannot be non-interleaved, if set this must be
975  // a mis-detection.
976  if (avi->dv_demux)
977  avi->non_interleaved = 0;
978  if (i == s->nb_streams && avi->non_interleaved) {
979  av_log(s, AV_LOG_WARNING,
980  "Non-interleaved AVI without index, switching to interleaved\n");
981  avi->non_interleaved = 0;
982  }
983 
984  if (avi->non_interleaved) {
985  av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
986  clean_index(s);
987  }
988 
989  ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
990  ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);
991 
992  return 0;
993 }
994 
995 static int read_gab2_sub(AVStream *st, AVPacket *pkt)
996 {
997  if (pkt->size >= 7 &&
998  pkt->size < INT_MAX - AVPROBE_PADDING_SIZE &&
999  !strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data + 5) == 2) {
1000  uint8_t desc[256];
1001  int score = AVPROBE_SCORE_EXTENSION, ret;
1002  AVIStream *ast = st->priv_data;
1003  AVInputFormat *sub_demuxer;
1004  AVRational time_base;
1005  int size;
1006  AVIOContext *pb = avio_alloc_context(pkt->data + 7,
1007  pkt->size - 7,
1008  0, NULL, NULL, NULL, NULL);
1009  AVProbeData pd;
1010  unsigned int desc_len = avio_rl32(pb);
1011 
1012  if (desc_len > pb->buf_end - pb->buf_ptr)
1013  goto error;
1014 
1015  ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
1016  avio_skip(pb, desc_len - ret);
1017  if (*desc)
1018  av_dict_set(&st->metadata, "title", desc, 0);
1019 
1020  avio_rl16(pb); /* flags? */
1021  avio_rl32(pb); /* data size */
1022 
1023  size = pb->buf_end - pb->buf_ptr;
1024  pd = (AVProbeData) { .buf = av_mallocz(size + AVPROBE_PADDING_SIZE),
1025  .buf_size = size };
1026  if (!pd.buf)
1027  goto error;
1028  memcpy(pd.buf, pb->buf_ptr, size);
1029  sub_demuxer = av_probe_input_format2(&pd, 1, &score);
1030  av_freep(&pd.buf);
1031  if (!sub_demuxer)
1032  goto error;
1033 
1034  if (!(ast->sub_ctx = avformat_alloc_context()))
1035  goto error;
1036 
1037  ast->sub_ctx->pb = pb;
1038  if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
1039  ff_read_packet(ast->sub_ctx, &ast->sub_pkt);
1040  *st->codec = *ast->sub_ctx->streams[0]->codec;
1041  ast->sub_ctx->streams[0]->codec->extradata = NULL;
1042  time_base = ast->sub_ctx->streams[0]->time_base;
1043  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
1044  }
1045  ast->sub_buffer = pkt->data;
1046  memset(pkt, 0, sizeof(*pkt));
1047  return 1;
1048 
1049 error:
1050  av_freep(&pb);
1051  }
1052  return 0;
1053 }
1054 
1055 static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,
1056  AVPacket *pkt)
1057 {
1058  AVIStream *ast, *next_ast = next_st->priv_data;
1059  int64_t ts, next_ts, ts_min = INT64_MAX;
1060  AVStream *st, *sub_st = NULL;
1061  int i;
1062 
1063  next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
1064  AV_TIME_BASE_Q);
1065 
1066  for (i = 0; i < s->nb_streams; i++) {
1067  st = s->streams[i];
1068  ast = st->priv_data;
1069  if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
1070  ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);
1071  if (ts <= next_ts && ts < ts_min) {
1072  ts_min = ts;
1073  sub_st = st;
1074  }
1075  }
1076  }
1077 
1078  if (sub_st) {
1079  ast = sub_st->priv_data;
1080  *pkt = ast->sub_pkt;
1081  pkt->stream_index = sub_st->index;
1082 
1083  if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
1084  ast->sub_pkt.data = NULL;
1085  }
1086  return sub_st;
1087 }
1088 
1089 static int get_stream_idx(unsigned *d)
1090 {
1091  if (d[0] >= '0' && d[0] <= '9' &&
1092  d[1] >= '0' && d[1] <= '9') {
1093  return (d[0] - '0') * 10 + (d[1] - '0');
1094  } else {
1095  return 100; // invalid stream ID
1096  }
1097 }
1098 
1099 /**
1100  *
1101  * @param exit_early set to 1 to just gather packet position without making the changes needed to actually read & return the packet
1102  */
1103 static int avi_sync(AVFormatContext *s, int exit_early)
1104 {
1105  AVIContext *avi = s->priv_data;
1106  AVIOContext *pb = s->pb;
1107  int n;
1108  unsigned int d[8];
1109  unsigned int size;
1110  int64_t i, sync;
1111 
1112 start_sync:
1113  memset(d, -1, sizeof(d));
1114  for (i = sync = avio_tell(pb); !avio_feof(pb); i++) {
1115  int j;
1116 
1117  for (j = 0; j < 7; j++)
1118  d[j] = d[j + 1];
1119  d[7] = avio_r8(pb);
1120 
1121  size = d[4] + (d[5] << 8) + (d[6] << 16) + (d[7] << 24);
1122 
1123  n = get_stream_idx(d + 2);
1124  av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",
1125  d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
1126  if (i*(avi->io_fsize>0) + (uint64_t)size > avi->fsize || d[0] > 127)
1127  continue;
1128 
1129  // parse ix##
1130  if ((d[0] == 'i' && d[1] == 'x' && n < s->nb_streams) ||
1131  // parse JUNK
1132  (d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K') ||
1133  (d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')) {
1134  avio_skip(pb, size);
1135  goto start_sync;
1136  }
1137 
1138  // parse stray LIST
1139  if (d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T') {
1140  avio_skip(pb, 4);
1141  goto start_sync;
1142  }
1143 
1144  n = avi->dv_demux ? 0 : get_stream_idx(d);
1145 
1146  if (!((i - avi->last_pkt_pos) & 1) &&
1147  get_stream_idx(d + 1) < s->nb_streams)
1148  continue;
1149 
1150  // detect ##ix chunk and skip
1151  if (d[2] == 'i' && d[3] == 'x' && n < s->nb_streams) {
1152  avio_skip(pb, size);
1153  goto start_sync;
1154  }
1155 
1156  // parse ##dc/##wb
1157  if (n < s->nb_streams) {
1158  AVStream *st;
1159  AVIStream *ast;
1160  st = s->streams[n];
1161  ast = st->priv_data;
1162 
1163  if (!ast) {
1164  av_log(s, AV_LOG_WARNING, "Skipping foreign stream %d packet\n", n);
1165  continue;
1166  }
1167 
1168  if (s->nb_streams >= 2) {
1169  AVStream *st1 = s->streams[1];
1170  AVIStream *ast1 = st1->priv_data;
1171  // workaround for broken small-file-bug402.avi
1172  if ( d[2] == 'w' && d[3] == 'b'
1173  && n == 0
1174  && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
1175  && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO
1176  && ast->prefix == 'd'*256+'c'
1177  && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
1178  ) {
1179  n = 1;
1180  st = st1;
1181  ast = ast1;
1182  av_log(s, AV_LOG_WARNING,
1183  "Invalid stream + prefix combination, assuming audio.\n");
1184  }
1185  }
1186 
1187  if (!avi->dv_demux &&
1188  ((st->discard >= AVDISCARD_DEFAULT && size == 0) /* ||
1189  // FIXME: needs a little reordering
1190  (st->discard >= AVDISCARD_NONKEY &&
1191  !(pkt->flags & AV_PKT_FLAG_KEY)) */
1192  || st->discard >= AVDISCARD_ALL)) {
1193  if (!exit_early) {
1194  ast->frame_offset += get_duration(ast, size);
1195  avio_skip(pb, size);
1196  goto start_sync;
1197  }
1198  }
1199 
1200  if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {
1201  int k = avio_r8(pb);
1202  int last = (k + avio_r8(pb) - 1) & 0xFF;
1203 
1204  avio_rl16(pb); // flags
1205 
1206  // b + (g << 8) + (r << 16);
1207  for (; k <= last; k++)
1208  ast->pal[k] = 0xFFU<<24 | avio_rb32(pb)>>8;
1209 
1210  ast->has_pal = 1;
1211  goto start_sync;
1212  } else if (((ast->prefix_count < 5 || sync + 9 > i) &&
1213  d[2] < 128 && d[3] < 128) ||
1214  d[2] * 256 + d[3] == ast->prefix /* ||
1215  (d[2] == 'd' && d[3] == 'c') ||
1216  (d[2] == 'w' && d[3] == 'b') */) {
1217  if (exit_early)
1218  return 0;
1219  if (d[2] * 256 + d[3] == ast->prefix)
1220  ast->prefix_count++;
1221  else {
1222  ast->prefix = d[2] * 256 + d[3];
1223  ast->prefix_count = 0;
1224  }
1225 
1226  avi->stream_index = n;
1227  ast->packet_size = size + 8;
1228  ast->remaining = size;
1229 
1230  if (size) {
1231  uint64_t pos = avio_tell(pb) - 8;
1232  if (!st->index_entries || !st->nb_index_entries ||
1233  st->index_entries[st->nb_index_entries - 1].pos < pos) {
1234  av_add_index_entry(st, pos, ast->frame_offset, size,
1235  0, AVINDEX_KEYFRAME);
1236  }
1237  }
1238  return 0;
1239  }
1240  }
1241  }
1242 
1243  if (pb->error)
1244  return pb->error;
1245  return AVERROR_EOF;
1246 }
1247 
1248 static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
1249 {
1250  AVIContext *avi = s->priv_data;
1251  AVIOContext *pb = s->pb;
1252  int err;
1253 #if FF_API_DESTRUCT_PACKET
1254  void *dstr;
1255 #endif
1256 
1257  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1258  int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
1259  if (size >= 0)
1260  return size;
1261  else
1262  goto resync;
1263  }
1264 
1265  if (avi->non_interleaved) {
1266  int best_stream_index = 0;
1267  AVStream *best_st = NULL;
1268  AVIStream *best_ast;
1269  int64_t best_ts = INT64_MAX;
1270  int i;
1271 
1272  for (i = 0; i < s->nb_streams; i++) {
1273  AVStream *st = s->streams[i];
1274  AVIStream *ast = st->priv_data;
1275  int64_t ts = ast->frame_offset;
1276  int64_t last_ts;
1277 
1278  if (!st->nb_index_entries)
1279  continue;
1280 
1281  last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
1282  if (!ast->remaining && ts > last_ts)
1283  continue;
1284 
1285  ts = av_rescale_q(ts, st->time_base,
1286  (AVRational) { FFMAX(1, ast->sample_size),
1287  AV_TIME_BASE });
1288 
1289  av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,
1290  st->time_base.num, st->time_base.den, ast->frame_offset);
1291  if (ts < best_ts) {
1292  best_ts = ts;
1293  best_st = st;
1294  best_stream_index = i;
1295  }
1296  }
1297  if (!best_st)
1298  return AVERROR_EOF;
1299 
1300  best_ast = best_st->priv_data;
1301  best_ts = best_ast->frame_offset;
1302  if (best_ast->remaining) {
1303  i = av_index_search_timestamp(best_st,
1304  best_ts,
1305  AVSEEK_FLAG_ANY |
1306  AVSEEK_FLAG_BACKWARD);
1307  } else {
1308  i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
1309  if (i >= 0)
1310  best_ast->frame_offset = best_st->index_entries[i].timestamp;
1311  }
1312 
1313  if (i >= 0) {
1314  int64_t pos = best_st->index_entries[i].pos;
1315  pos += best_ast->packet_size - best_ast->remaining;
1316  if (avio_seek(s->pb, pos + 8, SEEK_SET) < 0)
1317  return AVERROR_EOF;
1318 
1319  av_assert0(best_ast->remaining <= best_ast->packet_size);
1320 
1321  avi->stream_index = best_stream_index;
1322  if (!best_ast->remaining)
1323  best_ast->packet_size =
1324  best_ast->remaining = best_st->index_entries[i].size;
1325  }
1326  else
1327  return AVERROR_EOF;
1328  }
1329 
1330 resync:
1331  if (avi->stream_index >= 0) {
1332  AVStream *st = s->streams[avi->stream_index];
1333  AVIStream *ast = st->priv_data;
1334  int size, err;
1335 
1336  if (get_subtitle_pkt(s, st, pkt))
1337  return 0;
1338 
1339  // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
1340  if (ast->sample_size <= 1)
1341  size = INT_MAX;
1342  else if (ast->sample_size < 32)
1343  // arbitrary multiplier to avoid tiny packets for raw PCM data
1344  size = 1024 * ast->sample_size;
1345  else
1346  size = ast->sample_size;
1347 
1348  if (size > ast->remaining)
1349  size = ast->remaining;
1350  avi->last_pkt_pos = avio_tell(pb);
1351  err = av_get_packet(pb, pkt, size);
1352  if (err < 0)
1353  return err;
1354  size = err;
1355 
1356  if (ast->has_pal && pkt->size < (unsigned)INT_MAX / 2) {
1357  uint8_t *pal;
1358  pal = av_packet_new_side_data(pkt,
1359  AV_PKT_DATA_PALETTE,
1360  AVPALETTE_SIZE);
1361  if (!pal) {
1362  av_log(s, AV_LOG_ERROR,
1363  "Failed to allocate data for palette\n");
1364  } else {
1365  memcpy(pal, ast->pal, AVPALETTE_SIZE);
1366  ast->has_pal = 0;
1367  }
1368  }
1369 
1370  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1371  AVBufferRef *avbuf = pkt->buf;
1372 #if FF_API_DESTRUCT_PACKET
1373 FF_DISABLE_DEPRECATION_WARNINGS
1374  dstr = pkt->destruct;
1375 FF_ENABLE_DEPRECATION_WARNINGS
1376 #endif
1377  size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
1378  pkt->data, pkt->size, pkt->pos);
1379 #if FF_API_DESTRUCT_PACKET
1380 FF_DISABLE_DEPRECATION_WARNINGS
1381  pkt->destruct = dstr;
1382 FF_ENABLE_DEPRECATION_WARNINGS
1383 #endif
1384  pkt->buf = avbuf;
1385  pkt->flags |= AV_PKT_FLAG_KEY;
1386  if (size < 0)
1387  av_free_packet(pkt);
1388  } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&
1389  !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
1390  ast->frame_offset++;
1391  avi->stream_index = -1;
1392  ast->remaining = 0;
1393  goto resync;
1394  } else {
1395  /* XXX: How to handle B-frames in AVI? */
1396  pkt->dts = ast->frame_offset;
1397 // pkt->dts += ast->start;
1398  if (ast->sample_size)
1399  pkt->dts /= ast->sample_size;
1400  av_dlog(s,
1401  "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "
1402  "base:%d st:%d size:%d\n",
1403  pkt->dts,
1404  ast->frame_offset,
1405  ast->scale,
1406  ast->rate,
1407  ast->sample_size,
1408  AV_TIME_BASE,
1409  avi->stream_index,
1410  size);
1411  pkt->stream_index = avi->stream_index;
1412 
1413  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->index_entries) {
1414  AVIndexEntry *e;
1415  int index;
1416 
1417  index = av_index_search_timestamp(st, ast->frame_offset, AVSEEK_FLAG_ANY);
1418  e = &st->index_entries[index];
1419 
1420  if (index >= 0 && e->timestamp == ast->frame_offset) {
1421  if (index == st->nb_index_entries-1) {
1422  int key=1;
1423  int i;
1424  uint32_t state=-1;
1425  for (i=0; i<FFMIN(size,256); i++) {
1426  if (st->codec->codec_id == AV_CODEC_ID_MPEG4) {
1427  if (state == 0x1B6) {
1428  key= !(pkt->data[i]&0xC0);
1429  break;
1430  }
1431  }else
1432  break;
1433  state= (state<<8) + pkt->data[i];
1434  }
1435  if (!key)
1436  e->flags &= ~AVINDEX_KEYFRAME;
1437  }
1438  if (e->flags & AVINDEX_KEYFRAME)
1439  pkt->flags |= AV_PKT_FLAG_KEY;
1440  }
1441  } else {
1442  pkt->flags |= AV_PKT_FLAG_KEY;
1443  }
1444  ast->frame_offset += get_duration(ast, pkt->size);
1445  }
1446  ast->remaining -= err;
1447  if (!ast->remaining) {
1448  avi->stream_index = -1;
1449  ast->packet_size = 0;
1450  }
1451 
1452  if (!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos) {
1453  av_free_packet(pkt);
1454  goto resync;
1455  }
1456  ast->seek_pos= 0;
1457 
1458  if (!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1) {
1459  int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);
1460 
1461  if (avi->dts_max - dts > 2*AV_TIME_BASE) {
1462  avi->non_interleaved= 1;
1463  av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");
1464  }else if (avi->dts_max < dts)
1465  avi->dts_max = dts;
1466  }
1467 
1468  return 0;
1469  }
1470 
1471  if ((err = avi_sync(s, 0)) < 0)
1472  return err;
1473  goto resync;
1474 }
1475 
1476 /* XXX: We make the implicit supposition that the positions are sorted
1477  * for each stream. */
1478 static int avi_read_idx1(AVFormatContext *s, int size)
1479 {
1480  AVIContext *avi = s->priv_data;
1481  AVIOContext *pb = s->pb;
1482  int nb_index_entries, i;
1483  AVStream *st;
1484  AVIStream *ast;
1485  unsigned int index, tag, flags, pos, len, first_packet = 1;
1486  unsigned last_pos = -1;
1487  unsigned last_idx = -1;
1488  int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
1489  int anykey = 0;
1490 
1491  nb_index_entries = size / 16;
1492  if (nb_index_entries <= 0)
1493  return AVERROR_INVALIDDATA;
1494 
1495  idx1_pos = avio_tell(pb);
1496  avio_seek(pb, avi->movi_list + 4, SEEK_SET);
1497  if (avi_sync(s, 1) == 0)
1498  first_packet_pos = avio_tell(pb) - 8;
1499  avi->stream_index = -1;
1500  avio_seek(pb, idx1_pos, SEEK_SET);
1501 
1502  if (s->nb_streams == 1 && s->streams[0]->codec->codec_tag == AV_RL32("MMES")) {
1503  first_packet_pos = 0;
1504  data_offset = avi->movi_list;
1505  }
1506 
1507  /* Read the entries and sort them in each stream component. */
1508  for (i = 0; i < nb_index_entries; i++) {
1509  if (avio_feof(pb))
1510  return -1;
1511 
1512  tag = avio_rl32(pb);
1513  flags = avio_rl32(pb);
1514  pos = avio_rl32(pb);
1515  len = avio_rl32(pb);
1516  av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
1517  i, tag, flags, pos, len);
1518 
1519  index = ((tag & 0xff) - '0') * 10;
1520  index += (tag >> 8 & 0xff) - '0';
1521  if (index >= s->nb_streams)
1522  continue;
1523  st = s->streams[index];
1524  ast = st->priv_data;
1525 
1526  if (first_packet && first_packet_pos) {
1527  data_offset = first_packet_pos - pos;
1528  first_packet = 0;
1529  }
1530  pos += data_offset;
1531 
1532  av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
1533 
1534  // even if we have only a single stream, we should
1535  // switch to non-interleaved to get correct timestamps
1536  if (last_pos == pos)
1537  avi->non_interleaved = 1;
1538  if (last_idx != pos && len) {
1539  av_add_index_entry(st, pos, ast->cum_len, len, 0,
1540  (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
1541  last_idx= pos;
1542  }
1543  ast->cum_len += get_duration(ast, len);
1544  last_pos = pos;
1545  anykey |= flags&AVIIF_INDEX;
1546  }
1547  if (!anykey) {
1548  for (index = 0; index < s->nb_streams; index++) {
1549  st = s->streams[index];
1550  if (st->nb_index_entries)
1551  st->index_entries[0].flags |= AVINDEX_KEYFRAME;
1552  }
1553  }
1554  return 0;
1555 }
1556 
1557 /* Scan the index and consider any file with streams more than
1558  * 2 seconds or 64MB apart non-interleaved. */
1559 static int check_stream_max_drift(AVFormatContext *s)
1560 {
1561  int64_t min_pos, pos;
1562  int i;
1563  int *idx = av_mallocz_array(s->nb_streams, sizeof(*idx));
1564  if (!idx)
1565  return AVERROR(ENOMEM);
1566  for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {
1567  int64_t max_dts = INT64_MIN / 2;
1568  int64_t min_dts = INT64_MAX / 2;
1569  int64_t max_buffer = 0;
1570 
1571  min_pos = INT64_MAX;
1572 
1573  for (i = 0; i < s->nb_streams; i++) {
1574  AVStream *st = s->streams[i];
1575  AVIStream *ast = st->priv_data;
1576  int n = st->nb_index_entries;
1577  while (idx[i] < n && st->index_entries[idx[i]].pos < pos)
1578  idx[i]++;
1579  if (idx[i] < n) {
1580  int64_t dts;
1581  dts = av_rescale_q(st->index_entries[idx[i]].timestamp /
1582  FFMAX(ast->sample_size, 1),
1583  st->time_base, AV_TIME_BASE_Q);
1584  min_dts = FFMIN(min_dts, dts);
1585  min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
1586  }
1587  }
1588  for (i = 0; i < s->nb_streams; i++) {
1589  AVStream *st = s->streams[i];
1590  AVIStream *ast = st->priv_data;
1591 
1592  if (idx[i] && min_dts != INT64_MAX / 2) {
1593  int64_t dts;
1594  dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /
1595  FFMAX(ast->sample_size, 1),
1596  st->time_base, AV_TIME_BASE_Q);
1597  max_dts = FFMAX(max_dts, dts);
1598  max_buffer = FFMAX(max_buffer,
1599  av_rescale(dts - min_dts,
1600  st->codec->bit_rate,
1601  AV_TIME_BASE));
1602  }
1603  }
1604  if (max_dts - min_dts > 2 * AV_TIME_BASE ||
1605  max_buffer > 1024 * 1024 * 8 * 8) {
1606  av_free(idx);
1607  return 1;
1608  }
1609  }
1610  av_free(idx);
1611  return 0;
1612 }
1613 
1614 static int guess_ni_flag(AVFormatContext *s)
1615 {
1616  int i;
1617  int64_t last_start = 0;
1618  int64_t first_end = INT64_MAX;
1619  int64_t oldpos = avio_tell(s->pb);
1620 
1621  for (i = 0; i < s->nb_streams; i++) {
1622  AVStream *st = s->streams[i];
1623  int n = st->nb_index_entries;
1624  unsigned int size;
1625 
1626  if (n <= 0)
1627  continue;
1628 
1629  if (n >= 2) {
1630  int64_t pos = st->index_entries[0].pos;
1631  avio_seek(s->pb, pos + 4, SEEK_SET);
1632  size = avio_rl32(s->pb);
1633  if (pos + size > st->index_entries[1].pos)
1634  last_start = INT64_MAX;
1635  }
1636 
1637  if (st->index_entries[0].pos > last_start)
1638  last_start = st->index_entries[0].pos;
1639  if (st->index_entries[n - 1].pos < first_end)
1640  first_end = st->index_entries[n - 1].pos;
1641  }
1642  avio_seek(s->pb, oldpos, SEEK_SET);
1643 
1644  if (last_start > first_end)
1645  return 1;
1646 
1647  return check_stream_max_drift(s);
1648 }
1649 
1650 static int avi_load_index(AVFormatContext *s)
1651 {
1652  AVIContext *avi = s->priv_data;
1653  AVIOContext *pb = s->pb;
1654  uint32_t tag, size;
1655  int64_t pos = avio_tell(pb);
1656  int64_t next;
1657  int ret = -1;
1658 
1659  if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
1660  goto the_end; // maybe truncated file
1661  av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
1662  for (;;) {
1663  tag = avio_rl32(pb);
1664  size = avio_rl32(pb);
1665  if (avio_feof(pb))
1666  break;
1667  next = avio_tell(pb) + size + (size & 1);
1668 
1669  av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
1670  tag & 0xff,
1671  (tag >> 8) & 0xff,
1672  (tag >> 16) & 0xff,
1673  (tag >> 24) & 0xff,
1674  size);
1675 
1676  if (tag == MKTAG('i', 'd', 'x', '1') &&
1677  avi_read_idx1(s, size) >= 0) {
1678  avi->index_loaded=2;
1679  ret = 0;
1680  }else if (tag == MKTAG('L', 'I', 'S', 'T')) {
1681  uint32_t tag1 = avio_rl32(pb);
1682 
1683  if (tag1 == MKTAG('I', 'N', 'F', 'O'))
1684  ff_read_riff_info(s, size - 4);
1685  }else if (!ret)
1686  break;
1687 
1688  if (avio_seek(pb, next, SEEK_SET) < 0)
1689  break; // something is wrong here
1690  }
1691 
1692 the_end:
1693  avio_seek(pb, pos, SEEK_SET);
1694  return ret;
1695 }
1696 
1697 static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
1698 {
1699  AVIStream *ast2 = st2->priv_data;
1700  int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
1701  av_free_packet(&ast2->sub_pkt);
1702  if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
1703  avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
1704  ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
1705 }
1706 
1707 static int avi_read_seek(AVFormatContext *s, int stream_index,
1708  int64_t timestamp, int flags)
1709 {
1710  AVIContext *avi = s->priv_data;
1711  AVStream *st;
1712  int i, index;
1713  int64_t pos, pos_min;
1714  AVIStream *ast;
1715 
1716  /* Does not matter which stream is requested dv in avi has the
1717  * stream information in the first video stream.
1718  */
1719  if (avi->dv_demux)
1720  stream_index = 0;
1721 
1722  if (!avi->index_loaded) {
1723  /* we only load the index on demand */
1724  avi_load_index(s);
1725  avi->index_loaded |= 1;
1726  }
1727  av_assert0(stream_index >= 0);
1728 
1729  st = s->streams[stream_index];
1730  ast = st->priv_data;
1731  index = av_index_search_timestamp(st,
1732  timestamp * FFMAX(ast->sample_size, 1),
1733  flags);
1734  if (index < 0) {
1735  if (st->nb_index_entries > 0)
1736  av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",
1737  timestamp * FFMAX(ast->sample_size, 1),
1738  st->index_entries[0].timestamp,
1739  st->index_entries[st->nb_index_entries - 1].timestamp);
1740  return AVERROR_INVALIDDATA;
1741  }
1742 
1743  /* find the position */
1744  pos = st->index_entries[index].pos;
1745  timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
1746 
1747  av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",
1748  timestamp, index, st->index_entries[index].timestamp);
1749 
1750  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1751  /* One and only one real stream for DV in AVI, and it has video */
1752  /* offsets. Calling with other stream indexes should have failed */
1753  /* the av_index_search_timestamp call above. */
1754 
1755  if (avio_seek(s->pb, pos, SEEK_SET) < 0)
1756  return -1;
1757 
1758  /* Feed the DV video stream version of the timestamp to the */
1759  /* DV demux so it can synthesize correct timestamps. */
1760  ff_dv_offset_reset(avi->dv_demux, timestamp);
1761 
1762  avi->stream_index = -1;
1763  return 0;
1764  }
1765 
1766  pos_min = pos;
1767  for (i = 0; i < s->nb_streams; i++) {
1768  AVStream *st2 = s->streams[i];
1769  AVIStream *ast2 = st2->priv_data;
1770 
1771  ast2->packet_size =
1772  ast2->remaining = 0;
1773 
1774  if (ast2->sub_ctx) {
1775  seek_subtitle(st, st2, timestamp);
1776  continue;
1777  }
1778 
1779  if (st2->nb_index_entries <= 0)
1780  continue;
1781 
1782 // av_assert1(st2->codec->block_align);
1783  av_assert0(fabs(av_q2d(st2->time_base) - ast2->scale / (double)ast2->rate) < av_q2d(st2->time_base) * 0.00000001);
1784  index = av_index_search_timestamp(st2,
1785  av_rescale_q(timestamp,
1786  st->time_base,
1787  st2->time_base) *
1788  FFMAX(ast2->sample_size, 1),
1789  flags |
1790  AVSEEK_FLAG_BACKWARD |
1791  (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
1792  if (index < 0)
1793  index = 0;
1794  ast2->seek_pos = st2->index_entries[index].pos;
1795  pos_min = FFMIN(pos_min,ast2->seek_pos);
1796  }
1797  for (i = 0; i < s->nb_streams; i++) {
1798  AVStream *st2 = s->streams[i];
1799  AVIStream *ast2 = st2->priv_data;
1800 
1801  if (ast2->sub_ctx || st2->nb_index_entries <= 0)
1802  continue;
1803 
1804  index = av_index_search_timestamp(
1805  st2,
1806  av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1807  flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
1808  if (index < 0)
1809  index = 0;
1810  while (!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)
1811  index--;
1812  ast2->frame_offset = st2->index_entries[index].timestamp;
1813  }
1814 
1815  /* do the seek */
1816  if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {
1817  av_log(s, AV_LOG_ERROR, "Seek failed\n");
1818  return -1;
1819  }
1820  avi->stream_index = -1;
1821  avi->dts_max = INT_MIN;
1822  return 0;
1823 }
1824 
1825 static int avi_read_close(AVFormatContext *s)
1826 {
1827  int i;
1828  AVIContext *avi = s->priv_data;
1829 
1830  for (i = 0; i < s->nb_streams; i++) {
1831  AVStream *st = s->streams[i];
1832  AVIStream *ast = st->priv_data;
1833  if (ast) {
1834  if (ast->sub_ctx) {
1835  av_freep(&ast->sub_ctx->pb);
1836  avformat_close_input(&ast->sub_ctx);
1837  }
1838  av_free(ast->sub_buffer);
1839  av_free_packet(&ast->sub_pkt);
1840  }
1841  }
1842 
1843  av_free(avi->dv_demux);
1844 
1845  return 0;
1846 }
1847 
1848 static int avi_probe(AVProbeData *p)
1849 {
1850  int i;
1851 
1852  /* check file header */
1853  for (i = 0; avi_headers[i][0]; i++)
1854  if (!memcmp(p->buf, avi_headers[i], 4) &&
1855  !memcmp(p->buf + 8, avi_headers[i] + 4, 4))
1856  return AVPROBE_SCORE_MAX;
1857 
1858  return 0;
1859 }
1860 
1861 AVInputFormat ff_avi_demuxer = {
1862  .name = "avi",
1863  .long_name = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),
1864  .priv_data_size = sizeof(AVIContext),
1865  .extensions = "avi",
1866  .read_probe = avi_probe,
1867  .read_header = avi_read_header,
1868  .read_packet = avi_read_packet,
1869  .read_close = avi_read_close,
1870  .read_seek = avi_read_seek,
1871  .priv_class = &demuxer_class,
1872 };
Generated on Sun Sep 14 2014 18:56:11 for FFmpeg by   doxygen 1.8.2