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h264_refs.c
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1 /*
2  * H.26L/H.264/AVC/JVT/14496-10/... reference picture handling
3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * H.264 / AVC / MPEG-4 part10 reference picture handling.
25  * @author Michael Niedermayer <michaelni@gmx.at>
26  */
27 
28 #include <inttypes.h>
29 
30 #include "libavutil/avassert.h"
31 #include "internal.h"
32 #include "avcodec.h"
33 #include "h264.h"
34 #include "h264dec.h"
35 #include "golomb.h"
36 #include "mpegutils.h"
37 
38 #include <assert.h>
39 
40 static void pic_as_field(H264Ref *pic, const int parity)
41 {
42  int i;
43  for (i = 0; i < FF_ARRAY_ELEMS(pic->data); ++i) {
44  if (parity == PICT_BOTTOM_FIELD)
45  pic->data[i] += pic->linesize[i];
46  pic->reference = parity;
47  pic->linesize[i] *= 2;
48  }
49  pic->poc = pic->parent->field_poc[parity == PICT_BOTTOM_FIELD];
50 }
51 
53 {
54  memcpy(dst->data, src->f->data, sizeof(dst->data));
55  memcpy(dst->linesize, src->f->linesize, sizeof(dst->linesize));
56  dst->reference = src->reference;
57  dst->poc = src->poc;
58  dst->pic_id = src->pic_id;
59  dst->parent = src;
60 }
61 
62 static int split_field_copy(H264Ref *dest, H264Picture *src, int parity, int id_add)
63 {
64  int match = !!(src->reference & parity);
65 
66  if (match) {
67  ref_from_h264pic(dest, src);
68  if (parity != PICT_FRAME) {
69  pic_as_field(dest, parity);
70  dest->pic_id *= 2;
71  dest->pic_id += id_add;
72  }
73  }
74 
75  return match;
76 }
77 
78 static int build_def_list(H264Ref *def, int def_len,
79  H264Picture * const *in, int len, int is_long, int sel)
80 {
81  int i[2] = { 0 };
82  int index = 0;
83 
84  while (i[0] < len || i[1] < len) {
85  while (i[0] < len && !(in[i[0]] && (in[i[0]]->reference & sel)))
86  i[0]++;
87  while (i[1] < len && !(in[i[1]] && (in[i[1]]->reference & (sel ^ 3))))
88  i[1]++;
89  if (i[0] < len) {
90  av_assert0(index < def_len);
91  in[i[0]]->pic_id = is_long ? i[0] : in[i[0]]->frame_num;
92  split_field_copy(&def[index++], in[i[0]++], sel, 1);
93  }
94  if (i[1] < len) {
95  av_assert0(index < def_len);
96  in[i[1]]->pic_id = is_long ? i[1] : in[i[1]]->frame_num;
97  split_field_copy(&def[index++], in[i[1]++], sel ^ 3, 0);
98  }
99  }
100 
101  return index;
102 }
103 
104 static int add_sorted(H264Picture **sorted, H264Picture * const *src,
105  int len, int limit, int dir)
106 {
107  int i, best_poc;
108  int out_i = 0;
109 
110  for (;;) {
111  best_poc = dir ? INT_MIN : INT_MAX;
112 
113  for (i = 0; i < len; i++) {
114  const int poc = src[i]->poc;
115  if (((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)) {
116  best_poc = poc;
117  sorted[out_i] = src[i];
118  }
119  }
120  if (best_poc == (dir ? INT_MIN : INT_MAX))
121  break;
122  limit = sorted[out_i++]->poc - dir;
123  }
124  return out_i;
125 }
126 
127 static int mismatches_ref(const H264Context *h, const H264Picture *pic)
128 {
129  const AVFrame *f = pic->f;
130  return (h->cur_pic_ptr->f->width != f->width ||
131  h->cur_pic_ptr->f->height != f->height ||
132  h->cur_pic_ptr->f->format != f->format);
133 }
134 
136 {
137  int i, len;
138  int j;
139 
140  if (sl->slice_type_nos == AV_PICTURE_TYPE_B) {
141  H264Picture *sorted[32];
142  int cur_poc, list;
143  int lens[2];
144 
145  if (FIELD_PICTURE(h))
147  else
148  cur_poc = h->cur_pic_ptr->poc;
149 
150  for (list = 0; list < 2; list++) {
151  len = add_sorted(sorted, h->short_ref, h->short_ref_count, cur_poc, 1 ^ list);
152  len += add_sorted(sorted + len, h->short_ref, h->short_ref_count, cur_poc, 0 ^ list);
153  av_assert0(len <= 32);
154 
155  len = build_def_list(sl->ref_list[list], FF_ARRAY_ELEMS(sl->ref_list[0]),
156  sorted, len, 0, h->picture_structure);
157  len += build_def_list(sl->ref_list[list] + len,
158  FF_ARRAY_ELEMS(sl->ref_list[0]) - len,
159  h->long_ref, 16, 1, h->picture_structure);
160  av_assert0(len <= 32);
161 
162  if (len < sl->ref_count[list])
163  memset(&sl->ref_list[list][len], 0, sizeof(H264Ref) * (sl->ref_count[list] - len));
164  lens[list] = len;
165  }
166 
167  if (lens[0] == lens[1] && lens[1] > 1) {
168  for (i = 0; i < lens[0] &&
169  sl->ref_list[0][i].parent->f->buf[0]->buffer ==
170  sl->ref_list[1][i].parent->f->buf[0]->buffer; i++);
171  if (i == lens[0]) {
172  FFSWAP(H264Ref, sl->ref_list[1][0], sl->ref_list[1][1]);
173  }
174  }
175  } else {
176  len = build_def_list(sl->ref_list[0], FF_ARRAY_ELEMS(sl->ref_list[0]),
178  len += build_def_list(sl->ref_list[0] + len,
179  FF_ARRAY_ELEMS(sl->ref_list[0]) - len,
180  h-> long_ref, 16, 1, h->picture_structure);
181  av_assert0(len <= 32);
182 
183  if (len < sl->ref_count[0])
184  memset(&sl->ref_list[0][len], 0, sizeof(H264Ref) * (sl->ref_count[0] - len));
185  }
186 #ifdef TRACE
187  for (i = 0; i < sl->ref_count[0]; i++) {
188  ff_tlog(h->avctx, "List0: %s fn:%d 0x%p\n",
189  (sl->ref_list[0][i].parent ? (sl->ref_list[0][i].parent->long_ref ? "LT" : "ST") : "??"),
190  sl->ref_list[0][i].pic_id,
191  sl->ref_list[0][i].data[0]);
192  }
193  if (sl->slice_type_nos == AV_PICTURE_TYPE_B) {
194  for (i = 0; i < sl->ref_count[1]; i++) {
195  ff_tlog(h->avctx, "List1: %s fn:%d 0x%p\n",
196  (sl->ref_list[1][i].parent ? (sl->ref_list[1][i].parent->long_ref ? "LT" : "ST") : "??"),
197  sl->ref_list[1][i].pic_id,
198  sl->ref_list[1][i].data[0]);
199  }
200  }
201 #endif
202 
203  for (j = 0; j<1+(sl->slice_type_nos == AV_PICTURE_TYPE_B); j++) {
204  for (i = 0; i < sl->ref_count[j]; i++) {
205  if (sl->ref_list[j][i].parent) {
206  if (mismatches_ref(h, sl->ref_list[j][i].parent)) {
207  av_log(h->avctx, AV_LOG_ERROR, "Discarding mismatching reference\n");
208  memset(&sl->ref_list[j][i], 0, sizeof(sl->ref_list[j][i]));
209  }
210  }
211  }
212  }
213  for (i = 0; i < sl->list_count; i++)
214  h->default_ref[i] = sl->ref_list[i][0];
215 }
216 
217 /**
218  * print short term list
219  */
220 static void print_short_term(const H264Context *h)
221 {
222  uint32_t i;
223  if (h->avctx->debug & FF_DEBUG_MMCO) {
224  av_log(h->avctx, AV_LOG_DEBUG, "short term list:\n");
225  for (i = 0; i < h->short_ref_count; i++) {
226  H264Picture *pic = h->short_ref[i];
227  av_log(h->avctx, AV_LOG_DEBUG, "%"PRIu32" fn:%d poc:%d %p\n",
228  i, pic->frame_num, pic->poc, pic->f->data[0]);
229  }
230  }
231 }
232 
233 /**
234  * print long term list
235  */
236 static void print_long_term(const H264Context *h)
237 {
238  uint32_t i;
239  if (h->avctx->debug & FF_DEBUG_MMCO) {
240  av_log(h->avctx, AV_LOG_DEBUG, "long term list:\n");
241  for (i = 0; i < 16; i++) {
242  H264Picture *pic = h->long_ref[i];
243  if (pic) {
244  av_log(h->avctx, AV_LOG_DEBUG, "%"PRIu32" fn:%d poc:%d %p\n",
245  i, pic->frame_num, pic->poc, pic->f->data[0]);
246  }
247  }
248  }
249 }
250 
251 /**
252  * Extract structure information about the picture described by pic_num in
253  * the current decoding context (frame or field). Note that pic_num is
254  * picture number without wrapping (so, 0<=pic_num<max_pic_num).
255  * @param pic_num picture number for which to extract structure information
256  * @param structure one of PICT_XXX describing structure of picture
257  * with pic_num
258  * @return frame number (short term) or long term index of picture
259  * described by pic_num
260  */
261 static int pic_num_extract(const H264Context *h, int pic_num, int *structure)
262 {
263  *structure = h->picture_structure;
264  if (FIELD_PICTURE(h)) {
265  if (!(pic_num & 1))
266  /* opposite field */
267  *structure ^= PICT_FRAME;
268  pic_num >>= 1;
269  }
270 
271  return pic_num;
272 }
273 
275 {
276  int list, i, j;
277  for (list = 0; list < sl->list_count; list++) {
278  for (i = 0; i < sl->ref_count[list]; i++) {
279  H264Ref *frame = &sl->ref_list[list][i];
280  H264Ref *field = &sl->ref_list[list][16 + 2 * i];
281 
282  field[0] = *frame;
283 
284  for (j = 0; j < 3; j++)
285  field[0].linesize[j] <<= 1;
286  field[0].reference = PICT_TOP_FIELD;
287  field[0].poc = field[0].parent->field_poc[0];
288 
289  field[1] = field[0];
290 
291  for (j = 0; j < 3; j++)
292  field[1].data[j] += frame->parent->f->linesize[j];
293  field[1].reference = PICT_BOTTOM_FIELD;
294  field[1].poc = field[1].parent->field_poc[1];
295  }
296  }
297 }
298 
300 {
301  int list, index, pic_structure;
302 
303  print_short_term(h);
304  print_long_term(h);
305 
307 
308  for (list = 0; list < sl->list_count; list++) {
309  int pred = sl->curr_pic_num;
310 
311  for (index = 0; index < sl->nb_ref_modifications[list]; index++) {
312  unsigned int modification_of_pic_nums_idc = sl->ref_modifications[list][index].op;
313  unsigned int val = sl->ref_modifications[list][index].val;
314  unsigned int pic_id;
315  int i;
316  H264Picture *ref = NULL;
317 
318  switch (modification_of_pic_nums_idc) {
319  case 0:
320  case 1: {
321  const unsigned int abs_diff_pic_num = val + 1;
322  int frame_num;
323 
324  if (abs_diff_pic_num > sl->max_pic_num) {
326  "abs_diff_pic_num overflow\n");
327  return AVERROR_INVALIDDATA;
328  }
329 
330  if (modification_of_pic_nums_idc == 0)
331  pred -= abs_diff_pic_num;
332  else
333  pred += abs_diff_pic_num;
334  pred &= sl->max_pic_num - 1;
335 
336  frame_num = pic_num_extract(h, pred, &pic_structure);
337 
338  for (i = h->short_ref_count - 1; i >= 0; i--) {
339  ref = h->short_ref[i];
340  assert(ref->reference);
341  assert(!ref->long_ref);
342  if (ref->frame_num == frame_num &&
343  (ref->reference & pic_structure))
344  break;
345  }
346  if (i >= 0)
347  ref->pic_id = pred;
348  break;
349  }
350  case 2: {
351  int long_idx;
352  pic_id = val; // long_term_pic_idx
353 
354  long_idx = pic_num_extract(h, pic_id, &pic_structure);
355 
356  if (long_idx > 31U) {
358  "long_term_pic_idx overflow\n");
359  return AVERROR_INVALIDDATA;
360  }
361  ref = h->long_ref[long_idx];
362  assert(!(ref && !ref->reference));
363  if (ref && (ref->reference & pic_structure)) {
364  ref->pic_id = pic_id;
365  assert(ref->long_ref);
366  i = 0;
367  } else {
368  i = -1;
369  }
370  break;
371  }
372  default:
373  av_assert0(0);
374  }
375 
376  if (i < 0) {
378  "reference picture missing during reorder\n");
379  memset(&sl->ref_list[list][index], 0, sizeof(sl->ref_list[0][0])); // FIXME
380  } else {
381  for (i = index; i + 1 < sl->ref_count[list]; i++) {
382  if (sl->ref_list[list][i].parent &&
383  ref->long_ref == sl->ref_list[list][i].parent->long_ref &&
384  ref->pic_id == sl->ref_list[list][i].pic_id)
385  break;
386  }
387  for (; i > index; i--) {
388  sl->ref_list[list][i] = sl->ref_list[list][i - 1];
389  }
390  ref_from_h264pic(&sl->ref_list[list][index], ref);
391  if (FIELD_PICTURE(h)) {
392  pic_as_field(&sl->ref_list[list][index], pic_structure);
393  }
394  }
395  }
396  }
397  for (list = 0; list < sl->list_count; list++) {
398  for (index = 0; index < sl->ref_count[list]; index++) {
399  if ( !sl->ref_list[list][index].parent
400  || (!FIELD_PICTURE(h) && (sl->ref_list[list][index].reference&3) != 3)) {
401  int i;
402  av_log(h->avctx, AV_LOG_ERROR, "Missing reference picture, default is %d\n", h->default_ref[list].poc);
403  for (i = 0; i < FF_ARRAY_ELEMS(h->last_pocs); i++)
404  h->last_pocs[i] = INT_MIN;
405  if (h->default_ref[list].parent
406  && !(!FIELD_PICTURE(h) && (h->default_ref[list].reference&3) != 3))
407  sl->ref_list[list][index] = h->default_ref[list];
408  else
409  return -1;
410  }
411  av_assert0(av_buffer_get_ref_count(sl->ref_list[list][index].parent->f->buf[0]) > 0);
412  }
413  }
414 
415  if (FRAME_MBAFF(h))
417 
418  return 0;
419 }
420 
422 {
423  int list, index;
424 
425  sl->nb_ref_modifications[0] = 0;
426  sl->nb_ref_modifications[1] = 0;
427 
428  for (list = 0; list < sl->list_count; list++) {
429  if (!get_bits1(&sl->gb)) // ref_pic_list_modification_flag_l[01]
430  continue;
431 
432  for (index = 0; ; index++) {
433  unsigned int op = get_ue_golomb_31(&sl->gb);
434 
435  if (op == 3)
436  break;
437 
438  if (index >= sl->ref_count[list]) {
439  av_log(logctx, AV_LOG_ERROR, "reference count overflow\n");
440  return AVERROR_INVALIDDATA;
441  } else if (op > 2) {
442  av_log(logctx, AV_LOG_ERROR,
443  "illegal modification_of_pic_nums_idc %u\n",
444  op);
445  return AVERROR_INVALIDDATA;
446  }
447  sl->ref_modifications[list][index].val = get_ue_golomb_long(&sl->gb);
448  sl->ref_modifications[list][index].op = op;
449  sl->nb_ref_modifications[list]++;
450  }
451  }
452 
453  return 0;
454 }
455 
456 /**
457  * Mark a picture as no longer needed for reference. The refmask
458  * argument allows unreferencing of individual fields or the whole frame.
459  * If the picture becomes entirely unreferenced, but is being held for
460  * display purposes, it is marked as such.
461  * @param refmask mask of fields to unreference; the mask is bitwise
462  * anded with the reference marking of pic
463  * @return non-zero if pic becomes entirely unreferenced (except possibly
464  * for display purposes) zero if one of the fields remains in
465  * reference
466  */
467 static inline int unreference_pic(H264Context *h, H264Picture *pic, int refmask)
468 {
469  int i;
470  if (pic->reference &= refmask) {
471  return 0;
472  } else {
473  for(i = 0; h->delayed_pic[i]; i++)
474  if(pic == h->delayed_pic[i]){
475  pic->reference = DELAYED_PIC_REF;
476  break;
477  }
478  return 1;
479  }
480 }
481 
482 /**
483  * Find a H264Picture in the short term reference list by frame number.
484  * @param frame_num frame number to search for
485  * @param idx the index into h->short_ref where returned picture is found
486  * undefined if no picture found.
487  * @return pointer to the found picture, or NULL if no pic with the provided
488  * frame number is found
489  */
490 static H264Picture *find_short(H264Context *h, int frame_num, int *idx)
491 {
492  int i;
493 
494  for (i = 0; i < h->short_ref_count; i++) {
495  H264Picture *pic = h->short_ref[i];
496  if (h->avctx->debug & FF_DEBUG_MMCO)
497  av_log(h->avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
498  if (pic->frame_num == frame_num) {
499  *idx = i;
500  return pic;
501  }
502  }
503  return NULL;
504 }
505 
506 /**
507  * Remove a picture from the short term reference list by its index in
508  * that list. This does no checking on the provided index; it is assumed
509  * to be valid. Other list entries are shifted down.
510  * @param i index into h->short_ref of picture to remove.
511  */
512 static void remove_short_at_index(H264Context *h, int i)
513 {
514  assert(i >= 0 && i < h->short_ref_count);
515  h->short_ref[i] = NULL;
516  if (--h->short_ref_count)
517  memmove(&h->short_ref[i], &h->short_ref[i + 1],
518  (h->short_ref_count - i) * sizeof(H264Picture*));
519 }
520 
521 /**
522  * @return the removed picture or NULL if an error occurs
523  */
524 static H264Picture *remove_short(H264Context *h, int frame_num, int ref_mask)
525 {
526  H264Picture *pic;
527  int i;
528 
529  if (h->avctx->debug & FF_DEBUG_MMCO)
530  av_log(h->avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
531 
532  pic = find_short(h, frame_num, &i);
533  if (pic) {
534  if (unreference_pic(h, pic, ref_mask))
535  remove_short_at_index(h, i);
536  }
537 
538  return pic;
539 }
540 
541 /**
542  * Remove a picture from the long term reference list by its index in
543  * that list.
544  * @return the removed picture or NULL if an error occurs
545  */
546 static H264Picture *remove_long(H264Context *h, int i, int ref_mask)
547 {
548  H264Picture *pic;
549 
550  pic = h->long_ref[i];
551  if (pic) {
552  if (unreference_pic(h, pic, ref_mask)) {
553  assert(h->long_ref[i]->long_ref == 1);
554  h->long_ref[i]->long_ref = 0;
555  h->long_ref[i] = NULL;
556  h->long_ref_count--;
557  }
558  }
559 
560  return pic;
561 }
562 
564 {
565  int i;
566 
567  for (i = 0; i < 16; i++) {
568  remove_long(h, i, 0);
569  }
570  assert(h->long_ref_count == 0);
571 
572  if (h->short_ref_count && !h->last_pic_for_ec.f->data[0]) {
575  }
576 
577  for (i = 0; i < h->short_ref_count; i++) {
578  unreference_pic(h, h->short_ref[i], 0);
579  h->short_ref[i] = NULL;
580  }
581  h->short_ref_count = 0;
582 
583  memset(h->default_ref, 0, sizeof(h->default_ref));
584 }
585 
587 {
588  MMCO *mmco = h->mmco;
589  int nb_mmco = 0;
590 
591  if (h->short_ref_count &&
593  !(FIELD_PICTURE(h) && !h->first_field && h->cur_pic_ptr->reference)) {
594  mmco[0].opcode = MMCO_SHORT2UNUSED;
595  mmco[0].short_pic_num = h->short_ref[h->short_ref_count - 1]->frame_num;
596  nb_mmco = 1;
597  if (FIELD_PICTURE(h)) {
598  mmco[0].short_pic_num *= 2;
599  mmco[1].opcode = MMCO_SHORT2UNUSED;
600  mmco[1].short_pic_num = mmco[0].short_pic_num + 1;
601  nb_mmco = 2;
602  }
603  }
604 
605  h->nb_mmco = nb_mmco;
606 }
607 
609 {
610  MMCO *mmco = h->mmco;
611  int mmco_count;
612  int i, av_uninit(j);
613  int pps_ref_count[2] = {0};
614  int current_ref_assigned = 0, err = 0;
615  H264Picture *av_uninit(pic);
616 
617  if (!h->explicit_ref_marking)
619  mmco_count = h->nb_mmco;
620 
621  if ((h->avctx->debug & FF_DEBUG_MMCO) && mmco_count == 0)
622  av_log(h->avctx, AV_LOG_DEBUG, "no mmco here\n");
623 
624  for (i = 0; i < mmco_count; i++) {
625  int av_uninit(structure), av_uninit(frame_num);
626  if (h->avctx->debug & FF_DEBUG_MMCO)
627  av_log(h->avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode,
628  h->mmco[i].short_pic_num, h->mmco[i].long_arg);
629 
630  if (mmco[i].opcode == MMCO_SHORT2UNUSED ||
631  mmco[i].opcode == MMCO_SHORT2LONG) {
632  frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
633  pic = find_short(h, frame_num, &j);
634  if (!pic) {
635  if (mmco[i].opcode != MMCO_SHORT2LONG ||
636  !h->long_ref[mmco[i].long_arg] ||
637  h->long_ref[mmco[i].long_arg]->frame_num != frame_num) {
638  av_log(h->avctx, h->short_ref_count ? AV_LOG_ERROR : AV_LOG_DEBUG, "mmco: unref short failure\n");
639  err = AVERROR_INVALIDDATA;
640  }
641  continue;
642  }
643  }
644 
645  switch (mmco[i].opcode) {
646  case MMCO_SHORT2UNUSED:
647  if (h->avctx->debug & FF_DEBUG_MMCO)
648  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n",
650  remove_short(h, frame_num, structure ^ PICT_FRAME);
651  break;
652  case MMCO_SHORT2LONG:
653  if (h->long_ref[mmco[i].long_arg] != pic)
654  remove_long(h, mmco[i].long_arg, 0);
655 
656  remove_short_at_index(h, j);
657  h->long_ref[ mmco[i].long_arg ] = pic;
658  if (h->long_ref[mmco[i].long_arg]) {
659  h->long_ref[mmco[i].long_arg]->long_ref = 1;
660  h->long_ref_count++;
661  }
662  break;
663  case MMCO_LONG2UNUSED:
664  j = pic_num_extract(h, mmco[i].long_arg, &structure);
665  pic = h->long_ref[j];
666  if (pic) {
667  remove_long(h, j, structure ^ PICT_FRAME);
668  } else if (h->avctx->debug & FF_DEBUG_MMCO)
669  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
670  break;
671  case MMCO_LONG:
672  // Comment below left from previous code as it is an interesting note.
673  /* First field in pair is in short term list or
674  * at a different long term index.
675  * This is not allowed; see 7.4.3.3, notes 2 and 3.
676  * Report the problem and keep the pair where it is,
677  * and mark this field valid.
678  */
679  if (h->short_ref[0] == h->cur_pic_ptr) {
680  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to short and long at the same time\n");
681  remove_short_at_index(h, 0);
682  }
683 
684  /* make sure the current picture is not already assigned as a long ref */
685  if (h->cur_pic_ptr->long_ref) {
686  for (j = 0; j < FF_ARRAY_ELEMS(h->long_ref); j++) {
687  if (h->long_ref[j] == h->cur_pic_ptr) {
688  if (j != mmco[i].long_arg)
689  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to 2 long term references\n");
690  remove_long(h, j, 0);
691  }
692  }
693  }
694 
695  if (h->long_ref[mmco[i].long_arg] != h->cur_pic_ptr) {
697  remove_long(h, mmco[i].long_arg, 0);
698 
699  h->long_ref[mmco[i].long_arg] = h->cur_pic_ptr;
700  h->long_ref[mmco[i].long_arg]->long_ref = 1;
701  h->long_ref_count++;
702  }
703 
705  current_ref_assigned = 1;
706  break;
707  case MMCO_SET_MAX_LONG:
708  assert(mmco[i].long_arg <= 16);
709  // just remove the long term which index is greater than new max
710  for (j = mmco[i].long_arg; j < 16; j++) {
711  remove_long(h, j, 0);
712  }
713  break;
714  case MMCO_RESET:
715  while (h->short_ref_count) {
716  remove_short(h, h->short_ref[0]->frame_num, 0);
717  }
718  for (j = 0; j < 16; j++) {
719  remove_long(h, j, 0);
720  }
721  h->poc.frame_num = h->cur_pic_ptr->frame_num = 0;
722  h->mmco_reset = 1;
723  h->cur_pic_ptr->mmco_reset = 1;
724  for (j = 0; j < MAX_DELAYED_PIC_COUNT; j++)
725  h->last_pocs[j] = INT_MIN;
726  break;
727  default: assert(0);
728  }
729  }
730 
731  if (!current_ref_assigned) {
732  /* Second field of complementary field pair; the first field of
733  * which is already referenced. If short referenced, it
734  * should be first entry in short_ref. If not, it must exist
735  * in long_ref; trying to put it on the short list here is an
736  * error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
737  */
738  if (h->short_ref_count && h->short_ref[0] == h->cur_pic_ptr) {
739  /* Just mark the second field valid */
741  } else if (h->cur_pic_ptr->long_ref) {
742  av_log(h->avctx, AV_LOG_ERROR, "illegal short term reference "
743  "assignment for second field "
744  "in complementary field pair "
745  "(first field is long term)\n");
746  err = AVERROR_INVALIDDATA;
747  } else {
748  pic = remove_short(h, h->cur_pic_ptr->frame_num, 0);
749  if (pic) {
750  av_log(h->avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
751  err = AVERROR_INVALIDDATA;
752  }
753 
754  if (h->short_ref_count)
755  memmove(&h->short_ref[1], &h->short_ref[0],
756  h->short_ref_count * sizeof(H264Picture*));
757 
758  h->short_ref[0] = h->cur_pic_ptr;
759  h->short_ref_count++;
761  }
762  }
763 
764  if (h->long_ref_count + h->short_ref_count > FFMAX(h->ps.sps->ref_frame_count, 1)) {
765 
766  /* We have too many reference frames, probably due to corrupted
767  * stream. Need to discard one frame. Prevents overrun of the
768  * short_ref and long_ref buffers.
769  */
771  "number of reference frames (%d+%d) exceeds max (%d; probably "
772  "corrupt input), discarding one\n",
774  err = AVERROR_INVALIDDATA;
775 
776  if (h->long_ref_count && !h->short_ref_count) {
777  for (i = 0; i < 16; ++i)
778  if (h->long_ref[i])
779  break;
780 
781  assert(i < 16);
782  remove_long(h, i, 0);
783  } else {
784  pic = h->short_ref[h->short_ref_count - 1];
785  remove_short(h, pic->frame_num, 0);
786  }
787  }
788 
789  for (i = 0; i<h->short_ref_count; i++) {
790  pic = h->short_ref[i];
791  if (pic->invalid_gap) {
792  int d = av_mod_uintp2(h->cur_pic_ptr->frame_num - pic->frame_num, h->ps.sps->log2_max_frame_num);
793  if (d > h->ps.sps->ref_frame_count)
794  remove_short(h, pic->frame_num, 0);
795  }
796  }
797 
798  print_short_term(h);
799  print_long_term(h);
800 
801  for (i = 0; i < FF_ARRAY_ELEMS(h->ps.pps_list); i++) {
802  if (h->ps.pps_list[i]) {
803  const PPS *pps = (const PPS *)h->ps.pps_list[i]->data;
804  pps_ref_count[0] = FFMAX(pps_ref_count[0], pps->ref_count[0]);
805  pps_ref_count[1] = FFMAX(pps_ref_count[1], pps->ref_count[1]);
806  }
807  }
808 
809  if ( err >= 0
810  && h->long_ref_count==0
811  && ( h->short_ref_count<=2
812  || pps_ref_count[0] <= 1 + (h->picture_structure != PICT_FRAME) && pps_ref_count[1] <= 1)
813  && pps_ref_count[0]<=2 + (h->picture_structure != PICT_FRAME) + (2*!h->has_recovery_point)
815  h->cur_pic_ptr->recovered |= 1;
816  if(!h->avctx->has_b_frames)
818  }
819 
820  return (h->avctx->err_recognition & AV_EF_EXPLODE) ? err : 0;
821 }
822 
824  const H2645NAL *nal, void *logctx)
825 {
826  int i;
827  MMCO *mmco = sl->mmco;
828  int nb_mmco = 0;
829 
830  if (nal->type == H264_NAL_IDR_SLICE) { // FIXME fields
831  skip_bits1(gb); // broken_link
832  if (get_bits1(gb)) {
833  mmco[0].opcode = MMCO_LONG;
834  mmco[0].long_arg = 0;
835  nb_mmco = 1;
836  }
837  sl->explicit_ref_marking = 1;
838  } else {
840  if (sl->explicit_ref_marking) {
841  for (i = 0; i < MAX_MMCO_COUNT; i++) {
842  MMCOOpcode opcode = get_ue_golomb_31(gb);
843 
844  mmco[i].opcode = opcode;
845  if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) {
846  mmco[i].short_pic_num =
847  (sl->curr_pic_num - get_ue_golomb_long(gb) - 1) &
848  (sl->max_pic_num - 1);
849  }
850  if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
851  opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG) {
852  unsigned int long_arg = get_ue_golomb_31(gb);
853  if (long_arg >= 32 ||
854  (long_arg >= 16 && !(opcode == MMCO_SET_MAX_LONG &&
855  long_arg == 16) &&
856  !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE(sl)))) {
857  av_log(logctx, AV_LOG_ERROR,
858  "illegal long ref in memory management control "
859  "operation %d\n", opcode);
860  return -1;
861  }
862  mmco[i].long_arg = long_arg;
863  }
864 
865  if (opcode > (unsigned) MMCO_LONG) {
866  av_log(logctx, AV_LOG_ERROR,
867  "illegal memory management control operation %d\n",
868  opcode);
869  return -1;
870  }
871  if (opcode == MMCO_END)
872  break;
873  }
874  nb_mmco = i;
875  }
876  }
877 
878  sl->nb_mmco = nb_mmco;
879 
880  return 0;
881 }
static int split_field_copy(H264Ref *dest, H264Picture *src, int parity, int id_add)
Definition: h264_refs.c:62
#define ff_tlog(ctx,...)
Definition: internal.h:65
#define NULL
Definition: coverity.c:32
static int add_sorted(H264Picture **sorted, H264Picture *const *src, int len, int limit, int dir)
Definition: h264_refs.c:104
Memory management control operation.
Definition: h264dec.h:122
const char const char void * val
Definition: avisynth_c.h:771
int nb_mmco
Definition: h264dec.h:472
int long_ref
1->long term reference 0->short term reference
Definition: h264dec.h:154
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
H264POCContext poc
Definition: h264dec.h:458
This structure describes decoded (raw) audio or video data.
Definition: frame.h:187
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static H264Picture * remove_short(H264Context *h, int frame_num, int ref_mask)
Definition: h264_refs.c:524
int first_field
Definition: h264dec.h:406
int ff_h264_build_ref_list(H264Context *h, H264SliceContext *sl)
Definition: h264_refs.c:299
AVBufferRef * buf[AV_NUM_DATA_POINTERS]
AVBuffer references backing the data for this frame.
Definition: frame.h:370
MMCO mmco[MAX_MMCO_COUNT]
memory management control operations buffer.
Definition: h264dec.h:471
unsigned int ref_count[2]
num_ref_idx_l0/1_active_minus1 + 1
Definition: h264_ps.h:114
#define DELAYED_PIC_REF
Value of Picture.reference when Picture is not a reference picture, but is held for delayed output...
Definition: diracdec.c:66
Picture parameter set.
Definition: h264_ps.h:108
H264Picture * delayed_pic[MAX_DELAYED_PIC_COUNT+2]
Definition: h264dec.h:463
H264Ref default_ref[2]
Definition: h264dec.h:460
H264Context.
Definition: h264dec.h:341
AVFrame * f
Definition: h264dec.h:129
int nb_ref_modifications[2]
Definition: h264dec.h:280
H264Picture * long_ref[32]
Definition: h264dec.h:462
#define src
Definition: vp8dsp.c:254
int picture_structure
Definition: h264dec.h:405
static int mismatches_ref(const H264Context *h, const H264Picture *pic)
Definition: h264_refs.c:127
MMCOOpcode opcode
Definition: h264dec.h:123
unsigned int ref_count[2]
num_ref_idx_l0/1_active_minus1 + 1
Definition: h264dec.h:271
MMCO mmco[MAX_MMCO_COUNT]
Definition: h264dec.h:326
void ff_h264_remove_all_refs(H264Context *h)
Definition: h264_refs.c:563
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int short_pic_num
pic_num without wrapping (pic_num & max_pic_num)
Definition: h264dec.h:124
static void print_short_term(const H264Context *h)
print short term list
Definition: h264_refs.c:220
int poc
Definition: h264dec.h:175
int poc
frame POC
Definition: h264dec.h:148
static AVFrame * frame
int frame_recovered
Initial frame has been completely recovered.
Definition: h264dec.h:522
#define PICT_BOTTOM_FIELD
Definition: mpegutils.h:38
H264Picture * parent
Definition: h264dec.h:178
#define FRAME_RECOVERED_SEI
Sufficient number of frames have been decoded since a SEI recovery point, so all the following frames...
Definition: h264dec.h:520
int recovered
picture at IDR or recovery point + recovery count
Definition: h264dec.h:161
int ff_h264_decode_ref_pic_list_reordering(H264SliceContext *sl, void *logctx)
Definition: h264_refs.c:421
#define av_log(a,...)
int last_pocs[MAX_DELAYED_PIC_COUNT]
Definition: h264dec.h:464
H.264 common definitions.
#define U(x)
Definition: vp56_arith.h:37
int width
width and height of the video frame
Definition: frame.h:239
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:2054
int ff_h264_decode_ref_pic_marking(H264SliceContext *sl, GetBitContext *gb, const H2645NAL *nal, void *logctx)
Definition: h264_refs.c:823
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
#define FIELD_PICTURE(h)
Definition: h264dec.h:74
simple assert() macros that are a bit more flexible than ISO C assert().
#define PICT_TOP_FIELD
Definition: mpegutils.h:37
int frame_num
frame_num (raw frame_num from slice header)
Definition: h264dec.h:149
MMCOOpcode
Memory management control operation opcode.
Definition: h264dec.h:109
#define FFMAX(a, b)
Definition: common.h:94
int slice_type_nos
S free slice type (SI/SP are remapped to I/P)
Definition: h264dec.h:188
int pic_id
Definition: h264dec.h:176
static int unreference_pic(H264Context *h, H264Picture *pic, int refmask)
Mark a picture as no longer needed for reference.
Definition: h264_refs.c:467
uint8_t * data[3]
Definition: h264dec.h:171
int ref_frame_count
num_ref_frames
Definition: h264_ps.h:56
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:261
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:3020
int reference
Definition: h264dec.h:160
int long_ref_count
number of actual long term references
Definition: h264dec.h:476
mcdeint parity
Definition: vf_mcdeint.c:277
H.264 / AVC / MPEG-4 part10 codec.
int mmco_reset
Definition: h264dec.h:473
#define FF_DEBUG_MMCO
Definition: avcodec.h:2992
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:3031
int reference
Definition: h264dec.h:174
static void remove_short_at_index(H264Context *h, int i)
Remove a picture from the short term reference list by its index in that list.
Definition: h264_refs.c:512
static void ref_from_h264pic(H264Ref *dst, H264Picture *src)
Definition: h264_refs.c:52
int type
NAL unit type.
Definition: h2645_parse.h:52
#define FF_ARRAY_ELEMS(a)
static H264Picture * find_short(H264Context *h, int frame_num, int *idx)
Find a H264Picture in the short term reference list by frame number.
Definition: h264_refs.c:490
static const float pred[4]
Definition: siprdata.h:259
static unsigned get_ue_golomb_long(GetBitContext *gb)
Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
Definition: golomb.h:85
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:251
struct H264SliceContext::@66 ref_modifications[2][32]
static int pic_num_extract(const H264Context *h, int pic_num, int *structure)
Extract structure information about the picture described by pic_num in the current decoding context ...
Definition: h264_refs.c:261
AVCodecContext * avctx
Definition: h264dec.h:343
Libavcodec external API header.
#define MAX_DELAYED_PIC_COUNT
Definition: h264dec.h:56
AVBufferRef * pps_list[MAX_PPS_COUNT]
Definition: h264_ps.h:139
static int get_ue_golomb_31(GetBitContext *gb)
read unsigned exp golomb code, constraint to a max of 31.
Definition: golomb.h:100
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:218
H264Picture * short_ref[32]
Definition: h264dec.h:461
int explicit_ref_marking
Definition: h264dec.h:474
int field_poc[2]
top/bottom POC
Definition: h264dec.h:147
int debug
debug
Definition: avcodec.h:2973
int explicit_ref_marking
Definition: h264dec.h:328
uint8_t * data
The data buffer.
Definition: buffer.h:89
static void print_long_term(const H264Context *h)
print long term list
Definition: h264_refs.c:236
int av_buffer_get_ref_count(const AVBufferRef *buf)
Definition: buffer.c:146
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
AVBuffer * buffer
Definition: buffer.h:82
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:313
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:338
int index
Definition: gxfenc.c:89
#define FRAME_MBAFF(h)
Definition: h264dec.h:73
int ff_h264_ref_picture(H264Context *h, H264Picture *dst, H264Picture *src)
Definition: h264_picture.c:67
int mmco_reset
MMCO_RESET set this 1.
Definition: h264dec.h:150
static H264Picture * remove_long(H264Context *h, int i, int ref_mask)
Remove a picture from the long term reference list by its index in that list.
Definition: h264_refs.c:546
H264Picture * cur_pic_ptr
Definition: h264dec.h:350
const SPS * sps
Definition: h264_ps.h:145
int linesize[3]
Definition: h264dec.h:172
unsigned int list_count
Definition: h264dec.h:272
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:201
int has_recovery_point
Definition: h264dec.h:524
static int op(uint8_t **dst, const uint8_t *dst_end, GetByteContext *gb, int pixel, int count, int *x, int width, int linesize)
Perform decode operation.
Definition: anm.c:78
int pic_id
pic_num (short -> no wrap version of pic_num, pic_num & max_pic_num; long -> long_pic_num) ...
Definition: h264dec.h:152
static void pic_as_field(H264Ref *pic, const int parity)
Definition: h264_refs.c:40
common internal api header.
if(ret< 0)
Definition: vf_mcdeint.c:282
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
int log2_max_frame_num
log2_max_frame_num_minus4 + 4
Definition: h264_ps.h:49
H264ParamSets ps
Definition: h264dec.h:454
static void h264_fill_mbaff_ref_list(H264SliceContext *sl)
Definition: h264_refs.c:274
Bi-dir predicted.
Definition: avutil.h:276
uint8_t op
Definition: h264dec.h:277
int long_arg
index, pic_num, or num long refs depending on opcode
Definition: h264dec.h:125
#define PICT_FRAME
Definition: mpegutils.h:39
int len
static void h264_initialise_ref_list(H264Context *h, H264SliceContext *sl)
Definition: h264_refs.c:135
static int build_def_list(H264Ref *def, int def_len, H264Picture *const *in, int len, int is_long, int sel)
Definition: h264_refs.c:78
int ff_h264_execute_ref_pic_marking(H264Context *h)
Execute the reference picture marking (memory management control operations).
Definition: h264_refs.c:608
H264Ref ref_list[2][48]
0..15: frame refs, 16..47: mbaff field refs.
Definition: h264dec.h:273
H264Picture last_pic_for_ec
Definition: h264dec.h:352
#define av_uninit(x)
Definition: attributes.h:148
int height
Definition: frame.h:239
#define FFSWAP(type, a, b)
Definition: common.h:99
exp golomb vlc stuff
void ff_h264_unref_picture(H264Context *h, H264Picture *pic)
Definition: h264_picture.c:46
static void generate_sliding_window_mmcos(H264Context *h)
Definition: h264_refs.c:586
GetBitContext gb
Definition: h264dec.h:183
uint32_t val
Definition: h264dec.h:278
#define MAX_MMCO_COUNT
Definition: h264dec.h:54
int short_ref_count
number of actual short term references
Definition: h264dec.h:477