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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 / MPEG4 part10 reference picture handling.
25  * @author Michael Niedermayer <michaelni@gmx.at>
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "internal.h"
30 #include "avcodec.h"
31 #include "h264.h"
32 #include "golomb.h"
33 
34 //#undef NDEBUG
35 #include <assert.h>
36 
37 #define COPY_PICTURE(dst, src) \
38 do {\
39  *(dst) = *(src);\
40  (dst)->f.extended_data = (dst)->f.data;\
41  (dst)->tf.f = &(dst)->f;\
42 } while (0)
43 
44 
45 static void pic_as_field(Picture *pic, const int parity){
46  int i;
47  for (i = 0; i < 4; ++i) {
48  if (parity == PICT_BOTTOM_FIELD)
49  pic->f.data[i] += pic->f.linesize[i];
50  pic->reference = parity;
51  pic->f.linesize[i] *= 2;
52  }
53  pic->poc= pic->field_poc[parity == PICT_BOTTOM_FIELD];
54 }
55 
56 static int split_field_copy(Picture *dest, Picture *src, int parity, int id_add)
57 {
58  int match = !!(src->reference & parity);
59 
60  if (match) {
61  COPY_PICTURE(dest, src);
62  if (parity != PICT_FRAME) {
63  pic_as_field(dest, parity);
64  dest->pic_id *= 2;
65  dest->pic_id += id_add;
66  }
67  }
68 
69  return match;
70 }
71 
72 static int build_def_list(Picture *def, Picture **in, int len, int is_long, int sel)
73 {
74  int i[2] = { 0 };
75  int index = 0;
76 
77  while (i[0] < len || i[1] < len) {
78  while (i[0] < len && !(in[i[0]] && (in[i[0]]->reference & sel)))
79  i[0]++;
80  while (i[1] < len && !(in[i[1]] && (in[i[1]]->reference & (sel ^ 3))))
81  i[1]++;
82  if (i[0] < len) {
83  in[i[0]]->pic_id = is_long ? i[0] : in[i[0]]->frame_num;
84  split_field_copy(&def[index++], in[i[0]++], sel, 1);
85  }
86  if (i[1] < len) {
87  in[i[1]]->pic_id = is_long ? i[1] : in[i[1]]->frame_num;
88  split_field_copy(&def[index++], in[i[1]++], sel ^ 3, 0);
89  }
90  }
91 
92  return index;
93 }
94 
95 static int add_sorted(Picture **sorted, Picture **src, int len, int limit, int dir)
96 {
97  int i, best_poc;
98  int out_i = 0;
99 
100  for (;;) {
101  best_poc = dir ? INT_MIN : INT_MAX;
102 
103  for (i = 0; i < len; i++) {
104  const int poc = src[i]->poc;
105  if (((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)) {
106  best_poc = poc;
107  sorted[out_i] = src[i];
108  }
109  }
110  if (best_poc == (dir ? INT_MIN : INT_MAX))
111  break;
112  limit = sorted[out_i++]->poc - dir;
113  }
114  return out_i;
115 }
116 
118 {
119  int i, len;
120 
121  if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
122  Picture *sorted[32];
123  int cur_poc, list;
124  int lens[2];
125 
126  if (FIELD_PICTURE(h))
128  else
129  cur_poc = h->cur_pic_ptr->poc;
130 
131  for (list = 0; list < 2; list++) {
132  len = add_sorted(sorted, h->short_ref, h->short_ref_count, cur_poc, 1 ^ list);
133  len += add_sorted(sorted + len, h->short_ref, h->short_ref_count, cur_poc, 0 ^ list);
134  av_assert0(len <= 32);
135  len = build_def_list(h->default_ref_list[list], sorted, len, 0, h->picture_structure);
136  len += build_def_list(h->default_ref_list[list] + len, h->long_ref, 16, 1, h->picture_structure);
137  av_assert0(len <= 32);
138 
139  if (len < h->ref_count[list])
140  memset(&h->default_ref_list[list][len], 0, sizeof(Picture) * (h->ref_count[list] - len));
141  lens[list] = len;
142  }
143 
144  if (lens[0] == lens[1] && lens[1] > 1) {
145  for (i = 0; h->default_ref_list[0][i].f.data[0] == h->default_ref_list[1][i].f.data[0] && i < lens[0]; i++);
146  if (i == lens[0]) {
147  Picture tmp;
148  COPY_PICTURE(&tmp, &h->default_ref_list[1][0]);
149  COPY_PICTURE(&h->default_ref_list[1][0], &h->default_ref_list[1][1]);
150  COPY_PICTURE(&h->default_ref_list[1][1], &tmp);
151  }
152  }
153  } else {
155  len += build_def_list(h->default_ref_list[0] + len, h-> long_ref, 16, 1, h->picture_structure);
156  av_assert0(len <= 32);
157  if (len < h->ref_count[0])
158  memset(&h->default_ref_list[0][len], 0, sizeof(Picture) * (h->ref_count[0] - len));
159  }
160 #ifdef TRACE
161  for (i = 0; i < h->ref_count[0]; i++) {
162  tprintf(h->avctx, "List0: %s fn:%d 0x%p\n",
163  (h->default_ref_list[0][i].long_ref ? "LT" : "ST"),
164  h->default_ref_list[0][i].pic_id,
165  h->default_ref_list[0][i].f.data[0]);
166  }
167  if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
168  for (i = 0; i < h->ref_count[1]; i++) {
169  tprintf(h->avctx, "List1: %s fn:%d 0x%p\n",
170  (h->default_ref_list[1][i].long_ref ? "LT" : "ST"),
171  h->default_ref_list[1][i].pic_id,
172  h->default_ref_list[1][i].f.data[0]);
173  }
174  }
175 #endif
176  return 0;
177 }
178 
179 static void print_short_term(H264Context *h);
180 static void print_long_term(H264Context *h);
181 
182 /**
183  * Extract structure information about the picture described by pic_num in
184  * the current decoding context (frame or field). Note that pic_num is
185  * picture number without wrapping (so, 0<=pic_num<max_pic_num).
186  * @param pic_num picture number for which to extract structure information
187  * @param structure one of PICT_XXX describing structure of picture
188  * with pic_num
189  * @return frame number (short term) or long term index of picture
190  * described by pic_num
191  */
192 static int pic_num_extract(H264Context *h, int pic_num, int *structure)
193 {
194  *structure = h->picture_structure;
195  if (FIELD_PICTURE(h)) {
196  if (!(pic_num & 1))
197  /* opposite field */
198  *structure ^= PICT_FRAME;
199  pic_num >>= 1;
200  }
201 
202  return pic_num;
203 }
204 
206 {
207  int list, index, pic_structure, i;
208 
209  print_short_term(h);
210  print_long_term(h);
211 
212  for (list = 0; list < h->list_count; list++) {
213  for (i = 0; i < h->ref_count[list]; i++)
214  COPY_PICTURE(&h->ref_list[list][i], &h->default_ref_list[list][i]);
215 
216  if (get_bits1(&h->gb)) {
217  int pred = h->curr_pic_num;
218 
219  for (index = 0; ; index++) {
220  unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(&h->gb);
221  unsigned int pic_id;
222  int i;
223  Picture *ref = NULL;
224 
225  if (reordering_of_pic_nums_idc == 3)
226  break;
227 
228  if (index >= h->ref_count[list]) {
229  av_log(h->avctx, AV_LOG_ERROR, "reference count overflow\n");
230  return -1;
231  }
232 
233  if (reordering_of_pic_nums_idc < 3) {
234  if (reordering_of_pic_nums_idc < 2) {
235  const unsigned int abs_diff_pic_num = get_ue_golomb(&h->gb) + 1;
236  int frame_num;
237 
238  if (abs_diff_pic_num > h->max_pic_num) {
239  av_log(h->avctx, AV_LOG_ERROR, "abs_diff_pic_num overflow\n");
240  return -1;
241  }
242 
243  if (reordering_of_pic_nums_idc == 0)
244  pred -= abs_diff_pic_num;
245  else
246  pred += abs_diff_pic_num;
247  pred &= h->max_pic_num - 1;
248 
249  frame_num = pic_num_extract(h, pred, &pic_structure);
250 
251  for (i = h->short_ref_count - 1; i >= 0; i--) {
252  ref = h->short_ref[i];
253  assert(ref->reference);
254  assert(!ref->long_ref);
255  if (ref->frame_num == frame_num &&
256  (ref->reference & pic_structure))
257  break;
258  }
259  if (i >= 0)
260  ref->pic_id = pred;
261  } else {
262  int long_idx;
263  pic_id = get_ue_golomb(&h->gb); //long_term_pic_idx
264 
265  long_idx = pic_num_extract(h, pic_id, &pic_structure);
266 
267  if (long_idx > 31) {
268  av_log(h->avctx, AV_LOG_ERROR, "long_term_pic_idx overflow\n");
269  return -1;
270  }
271  ref = h->long_ref[long_idx];
272  assert(!(ref && !ref->reference));
273  if (ref && (ref->reference & pic_structure)) {
274  ref->pic_id = pic_id;
275  assert(ref->long_ref);
276  i = 0;
277  } else {
278  i = -1;
279  }
280  }
281 
282  if (i < 0) {
283  av_log(h->avctx, AV_LOG_ERROR, "reference picture missing during reorder\n");
284  memset(&h->ref_list[list][index], 0, sizeof(Picture)); //FIXME
285  } else {
286  for (i = index; i + 1 < h->ref_count[list]; i++) {
287  if (ref->long_ref == h->ref_list[list][i].long_ref &&
288  ref->pic_id == h->ref_list[list][i].pic_id)
289  break;
290  }
291  for (; i > index; i--) {
292  COPY_PICTURE(&h->ref_list[list][i], &h->ref_list[list][i - 1]);
293  }
294  COPY_PICTURE(&h->ref_list[list][index], ref);
295  if (FIELD_PICTURE(h)) {
296  pic_as_field(&h->ref_list[list][index], pic_structure);
297  }
298  }
299  } else {
300  av_log(h->avctx, AV_LOG_ERROR, "illegal reordering_of_pic_nums_idc\n");
301  return -1;
302  }
303  }
304  }
305  }
306  for (list = 0; list < h->list_count; list++) {
307  for (index = 0; index < h->ref_count[list]; index++) {
308  if ( !h->ref_list[list][index].f.data[0]
309  || (!FIELD_PICTURE(h) && (h->ref_list[list][index].reference&3) != 3)) {
310  int i;
311  av_log(h->avctx, AV_LOG_ERROR, "Missing reference picture, default is %d\n", h->default_ref_list[list][0].poc);
312  for (i = 0; i < FF_ARRAY_ELEMS(h->last_pocs); i++)
313  h->last_pocs[i] = INT_MIN;
314  if (h->default_ref_list[list][0].f.data[0]
315  && !(!FIELD_PICTURE(h) && (h->default_ref_list[list][0].reference&3) != 3))
316  COPY_PICTURE(&h->ref_list[list][index], &h->default_ref_list[list][0]);
317  else
318  return -1;
319  }
320  av_assert0(av_buffer_get_ref_count(h->ref_list[list][index].f.buf[0]) > 0);
321  }
322  }
323 
324  return 0;
325 }
326 
328 {
329  int list, i, j;
330  for (list = 0; list < h->list_count; list++) {
331  for (i = 0; i < h->ref_count[list]; i++) {
332  Picture *frame = &h->ref_list[list][i];
333  Picture *field = &h->ref_list[list][16 + 2 * i];
334  COPY_PICTURE(field, frame);
335  for (j = 0; j < 3; j++)
336  field[0].f.linesize[j] <<= 1;
337  field[0].reference = PICT_TOP_FIELD;
338  field[0].poc = field[0].field_poc[0];
339  COPY_PICTURE(field + 1, field);
340  for (j = 0; j < 3; j++)
341  field[1].f.data[j] += frame->f.linesize[j];
342  field[1].reference = PICT_BOTTOM_FIELD;
343  field[1].poc = field[1].field_poc[1];
344 
345  h->luma_weight[16 + 2 * i][list][0] = h->luma_weight[16 + 2 * i + 1][list][0] = h->luma_weight[i][list][0];
346  h->luma_weight[16 + 2 * i][list][1] = h->luma_weight[16 + 2 * i + 1][list][1] = h->luma_weight[i][list][1];
347  for (j = 0; j < 2; j++) {
348  h->chroma_weight[16 + 2 * i][list][j][0] = h->chroma_weight[16 + 2 * i + 1][list][j][0] = h->chroma_weight[i][list][j][0];
349  h->chroma_weight[16 + 2 * i][list][j][1] = h->chroma_weight[16 + 2 * i + 1][list][j][1] = h->chroma_weight[i][list][j][1];
350  }
351  }
352  }
353 }
354 
355 /**
356  * Mark a picture as no longer needed for reference. The refmask
357  * argument allows unreferencing of individual fields or the whole frame.
358  * If the picture becomes entirely unreferenced, but is being held for
359  * display purposes, it is marked as such.
360  * @param refmask mask of fields to unreference; the mask is bitwise
361  * anded with the reference marking of pic
362  * @return non-zero if pic becomes entirely unreferenced (except possibly
363  * for display purposes) zero if one of the fields remains in
364  * reference
365  */
366 static inline int unreference_pic(H264Context *h, Picture *pic, int refmask)
367 {
368  int i;
369  if (pic->reference &= refmask) {
370  return 0;
371  } else {
372  for(i = 0; h->delayed_pic[i]; i++)
373  if(pic == h->delayed_pic[i]){
374  pic->reference = DELAYED_PIC_REF;
375  break;
376  }
377  return 1;
378  }
379 }
380 
381 /**
382  * Find a Picture in the short term reference list by frame number.
383  * @param frame_num frame number to search for
384  * @param idx the index into h->short_ref where returned picture is found
385  * undefined if no picture found.
386  * @return pointer to the found picture, or NULL if no pic with the provided
387  * frame number is found
388  */
389 static Picture *find_short(H264Context *h, int frame_num, int *idx)
390 {
391  int i;
392 
393  for (i = 0; i < h->short_ref_count; i++) {
394  Picture *pic = h->short_ref[i];
395  if (h->avctx->debug & FF_DEBUG_MMCO)
396  av_log(h->avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
397  if (pic->frame_num == frame_num) {
398  *idx = i;
399  return pic;
400  }
401  }
402  return NULL;
403 }
404 
405 /**
406  * Remove a picture from the short term reference list by its index in
407  * that list. This does no checking on the provided index; it is assumed
408  * to be valid. Other list entries are shifted down.
409  * @param i index into h->short_ref of picture to remove.
410  */
411 static void remove_short_at_index(H264Context *h, int i)
412 {
413  assert(i >= 0 && i < h->short_ref_count);
414  h->short_ref[i] = NULL;
415  if (--h->short_ref_count)
416  memmove(&h->short_ref[i], &h->short_ref[i + 1],
417  (h->short_ref_count - i) * sizeof(Picture*));
418 }
419 
420 /**
421  *
422  * @return the removed picture or NULL if an error occurs
423  */
424 static Picture *remove_short(H264Context *h, int frame_num, int ref_mask)
425 {
426  Picture *pic;
427  int i;
428 
429  if (h->avctx->debug & FF_DEBUG_MMCO)
430  av_log(h->avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
431 
432  pic = find_short(h, frame_num, &i);
433  if (pic) {
434  if (unreference_pic(h, pic, ref_mask))
435  remove_short_at_index(h, i);
436  }
437 
438  return pic;
439 }
440 
441 /**
442  * Remove a picture from the long term reference list by its index in
443  * that list.
444  * @return the removed picture or NULL if an error occurs
445  */
446 static Picture *remove_long(H264Context *h, int i, int ref_mask)
447 {
448  Picture *pic;
449 
450  pic = h->long_ref[i];
451  if (pic) {
452  if (unreference_pic(h, pic, ref_mask)) {
453  assert(h->long_ref[i]->long_ref == 1);
454  h->long_ref[i]->long_ref = 0;
455  h->long_ref[i] = NULL;
456  h->long_ref_count--;
457  }
458  }
459 
460  return pic;
461 }
462 
464 {
465  int i;
466 
467  for (i = 0; i < 16; i++) {
468  remove_long(h, i, 0);
469  }
470  assert(h->long_ref_count == 0);
471 
472  for (i = 0; i < h->short_ref_count; i++) {
473  unreference_pic(h, h->short_ref[i], 0);
474  h->short_ref[i] = NULL;
475  }
476  h->short_ref_count = 0;
477 
478  memset(h->default_ref_list, 0, sizeof(h->default_ref_list));
479  memset(h->ref_list, 0, sizeof(h->ref_list));
480 }
481 
482 /**
483  * print short term list
484  */
486 {
487  uint32_t i;
488  if (h->avctx->debug & FF_DEBUG_MMCO) {
489  av_log(h->avctx, AV_LOG_DEBUG, "short term list:\n");
490  for (i = 0; i < h->short_ref_count; i++) {
491  Picture *pic = h->short_ref[i];
492  av_log(h->avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n",
493  i, pic->frame_num, pic->poc, pic->f.data[0]);
494  }
495  }
496 }
497 
498 /**
499  * print long term list
500  */
502 {
503  uint32_t i;
504  if (h->avctx->debug & FF_DEBUG_MMCO) {
505  av_log(h->avctx, AV_LOG_DEBUG, "long term list:\n");
506  for (i = 0; i < 16; i++) {
507  Picture *pic = h->long_ref[i];
508  if (pic) {
509  av_log(h->avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n",
510  i, pic->frame_num, pic->poc, pic->f.data[0]);
511  }
512  }
513  }
514 }
515 
516 static int check_opcodes(MMCO *mmco1, MMCO *mmco2, int n_mmcos)
517 {
518  int i;
519 
520  for (i = 0; i < n_mmcos; i++) {
521  if (mmco1[i].opcode != mmco2[i].opcode) {
522  av_log(NULL, AV_LOG_ERROR, "MMCO opcode [%d, %d] at %d mismatches between slices\n",
523  mmco1[i].opcode, mmco2[i].opcode, i);
524  return -1;
525  }
526  }
527 
528  return 0;
529 }
530 
532 {
533  MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = first_slice ? h->mmco : mmco_temp;
534  int mmco_index = 0, i;
535 
536  if (h->short_ref_count &&
538  !(FIELD_PICTURE(h) && !h->first_field && h->cur_pic_ptr->reference)) {
539  mmco[0].opcode = MMCO_SHORT2UNUSED;
540  mmco[0].short_pic_num = h->short_ref[h->short_ref_count - 1]->frame_num;
541  mmco_index = 1;
542  if (FIELD_PICTURE(h)) {
543  mmco[0].short_pic_num *= 2;
544  mmco[1].opcode = MMCO_SHORT2UNUSED;
545  mmco[1].short_pic_num = mmco[0].short_pic_num + 1;
546  mmco_index = 2;
547  }
548  }
549 
550  if (first_slice) {
551  h->mmco_index = mmco_index;
552  } else if (!first_slice && mmco_index >= 0 &&
553  (mmco_index != h->mmco_index ||
554  (i = check_opcodes(h->mmco, mmco_temp, mmco_index)))) {
556  "Inconsistent MMCO state between slices [%d, %d]\n",
557  mmco_index, h->mmco_index);
558  return AVERROR_INVALIDDATA;
559  }
560  return 0;
561 }
562 
563 int ff_h264_execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count)
564 {
565  int i, av_uninit(j);
566  int current_ref_assigned = 0, err = 0;
567  Picture *av_uninit(pic);
568 
569  if ((h->avctx->debug & FF_DEBUG_MMCO) && mmco_count == 0)
570  av_log(h->avctx, AV_LOG_DEBUG, "no mmco here\n");
571 
572  for (i = 0; i < mmco_count; i++) {
573  int av_uninit(structure), av_uninit(frame_num);
574  if (h->avctx->debug & FF_DEBUG_MMCO)
575  av_log(h->avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode,
576  h->mmco[i].short_pic_num, h->mmco[i].long_arg);
577 
578  if (mmco[i].opcode == MMCO_SHORT2UNUSED ||
579  mmco[i].opcode == MMCO_SHORT2LONG) {
580  frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
581  pic = find_short(h, frame_num, &j);
582  if (!pic) {
583  if (mmco[i].opcode != MMCO_SHORT2LONG ||
584  !h->long_ref[mmco[i].long_arg] ||
585  h->long_ref[mmco[i].long_arg]->frame_num != frame_num) {
586  av_log(h->avctx, AV_LOG_ERROR, "mmco: unref short failure\n");
587  err = AVERROR_INVALIDDATA;
588  }
589  continue;
590  }
591  }
592 
593  switch (mmco[i].opcode) {
594  case MMCO_SHORT2UNUSED:
595  if (h->avctx->debug & FF_DEBUG_MMCO)
596  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n",
598  remove_short(h, frame_num, structure ^ PICT_FRAME);
599  break;
600  case MMCO_SHORT2LONG:
601  if (h->long_ref[mmco[i].long_arg] != pic)
602  remove_long(h, mmco[i].long_arg, 0);
603 
604  remove_short_at_index(h, j);
605  h->long_ref[ mmco[i].long_arg ] = pic;
606  if (h->long_ref[mmco[i].long_arg]) {
607  h->long_ref[mmco[i].long_arg]->long_ref = 1;
608  h->long_ref_count++;
609  }
610  break;
611  case MMCO_LONG2UNUSED:
612  j = pic_num_extract(h, mmco[i].long_arg, &structure);
613  pic = h->long_ref[j];
614  if (pic) {
615  remove_long(h, j, structure ^ PICT_FRAME);
616  } else if (h->avctx->debug & FF_DEBUG_MMCO)
617  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
618  break;
619  case MMCO_LONG:
620  // Comment below left from previous code as it is an interresting note.
621  /* First field in pair is in short term list or
622  * at a different long term index.
623  * This is not allowed; see 7.4.3.3, notes 2 and 3.
624  * Report the problem and keep the pair where it is,
625  * and mark this field valid.
626  */
627 
628  if (h->long_ref[mmco[i].long_arg] != h->cur_pic_ptr) {
629  if (h->cur_pic_ptr->long_ref) {
630  for(j=0; j<16; j++) {
631  if(h->long_ref[j] == h->cur_pic_ptr) {
632  remove_long(h, j, 0);
633  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to 2 long term references\n");
634  }
635  }
636  }
638  remove_long(h, mmco[i].long_arg, 0);
639  if (remove_short(h, h->cur_pic_ptr->frame_num, 0)) {
640  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to short and long at the same time\n");
641  }
642 
643  h->long_ref[mmco[i].long_arg] = h->cur_pic_ptr;
644  h->long_ref[mmco[i].long_arg]->long_ref = 1;
645  h->long_ref_count++;
646  }
647 
649  current_ref_assigned = 1;
650  break;
651  case MMCO_SET_MAX_LONG:
652  assert(mmco[i].long_arg <= 16);
653  // just remove the long term which index is greater than new max
654  for (j = mmco[i].long_arg; j < 16; j++) {
655  remove_long(h, j, 0);
656  }
657  break;
658  case MMCO_RESET:
659  while (h->short_ref_count) {
660  remove_short(h, h->short_ref[0]->frame_num, 0);
661  }
662  for (j = 0; j < 16; j++) {
663  remove_long(h, j, 0);
664  }
665  h->frame_num = h->cur_pic_ptr->frame_num = 0;
666  h->mmco_reset = 1;
667  h->cur_pic_ptr->mmco_reset = 1;
668  for (j = 0; j < MAX_DELAYED_PIC_COUNT; j++)
669  h->last_pocs[j] = INT_MIN;
670  break;
671  default: assert(0);
672  }
673  }
674 
675  if (!current_ref_assigned) {
676  /* Second field of complementary field pair; the first field of
677  * which is already referenced. If short referenced, it
678  * should be first entry in short_ref. If not, it must exist
679  * in long_ref; trying to put it on the short list here is an
680  * error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
681  */
682  if (h->short_ref_count && h->short_ref[0] == h->cur_pic_ptr) {
683  /* Just mark the second field valid */
685  } else if (h->cur_pic_ptr->long_ref) {
686  av_log(h->avctx, AV_LOG_ERROR, "illegal short term reference "
687  "assignment for second field "
688  "in complementary field pair "
689  "(first field is long term)\n");
690  err = AVERROR_INVALIDDATA;
691  } else {
692  pic = remove_short(h, h->cur_pic_ptr->frame_num, 0);
693  if (pic) {
694  av_log(h->avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
695  err = AVERROR_INVALIDDATA;
696  }
697 
698  if (h->short_ref_count)
699  memmove(&h->short_ref[1], &h->short_ref[0],
700  h->short_ref_count * sizeof(Picture*));
701 
702  h->short_ref[0] = h->cur_pic_ptr;
703  h->short_ref_count++;
705  }
706  }
707 
708  if (h->long_ref_count + h->short_ref_count > FFMAX(h->sps.ref_frame_count, 1)) {
709 
710  /* We have too many reference frames, probably due to corrupted
711  * stream. Need to discard one frame. Prevents overrun of the
712  * short_ref and long_ref buffers.
713  */
715  "number of reference frames (%d+%d) exceeds max (%d; probably "
716  "corrupt input), discarding one\n",
718  err = AVERROR_INVALIDDATA;
719 
720  if (h->long_ref_count && !h->short_ref_count) {
721  for (i = 0; i < 16; ++i)
722  if (h->long_ref[i])
723  break;
724 
725  assert(i < 16);
726  remove_long(h, i, 0);
727  } else {
728  pic = h->short_ref[h->short_ref_count - 1];
729  remove_short(h, pic->frame_num, 0);
730  }
731  }
732 
733  print_short_term(h);
734  print_long_term(h);
735 
736  if(err >= 0 && h->long_ref_count==0 && h->short_ref_count<=2 && h->pps.ref_count[0]<=1 + (h->picture_structure != PICT_FRAME) && h->cur_pic_ptr->f.pict_type == AV_PICTURE_TYPE_I){
737  h->cur_pic_ptr->sync |= 1;
738  if(!h->avctx->has_b_frames)
739  h->sync = 2;
740  }
741 
742  return (h->avctx->err_recognition & AV_EF_EXPLODE) ? err : 0;
743 }
744 
746  int first_slice)
747 {
748  int i, ret;
749  MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = mmco_temp;
750  int mmco_index = 0;
751 
752  if (h->nal_unit_type == NAL_IDR_SLICE) { // FIXME fields
753  skip_bits1(gb); // broken_link
754  if (get_bits1(gb)) {
755  mmco[0].opcode = MMCO_LONG;
756  mmco[0].long_arg = 0;
757  mmco_index = 1;
758  }
759  } else {
760  if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
761  for (i = 0; i < MAX_MMCO_COUNT; i++) {
762  MMCOOpcode opcode = get_ue_golomb_31(gb);
763 
764  mmco[i].opcode = opcode;
765  if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) {
766  mmco[i].short_pic_num =
767  (h->curr_pic_num - get_ue_golomb(gb) - 1) &
768  (h->max_pic_num - 1);
769 #if 0
770  if (mmco[i].short_pic_num >= h->short_ref_count ||
771  h->short_ref[ mmco[i].short_pic_num ] == NULL){
772  av_log(s->avctx, AV_LOG_ERROR,
773  "illegal short ref in memory management control "
774  "operation %d\n", mmco);
775  return -1;
776  }
777 #endif
778  }
779  if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
780  opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG) {
781  unsigned int long_arg = get_ue_golomb_31(gb);
782  if (long_arg >= 32 ||
783  (long_arg >= 16 && !(opcode == MMCO_SET_MAX_LONG &&
784  long_arg == 16) &&
785  !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE(h)))) {
787  "illegal long ref in memory management control "
788  "operation %d\n", opcode);
789  return -1;
790  }
791  mmco[i].long_arg = long_arg;
792  }
793 
794  if (opcode > (unsigned) MMCO_LONG) {
796  "illegal memory management control operation %d\n",
797  opcode);
798  return -1;
799  }
800  if (opcode == MMCO_END)
801  break;
802  }
803  mmco_index = i;
804  } else {
805  if (first_slice) {
806  ret = ff_generate_sliding_window_mmcos(h, first_slice);
807  if (ret < 0 && h->avctx->err_recognition & AV_EF_EXPLODE)
808  return ret;
809  }
810  mmco_index = -1;
811  }
812  }
813 
814  if (first_slice && mmco_index != -1) {
815  memcpy(h->mmco, mmco_temp, sizeof(h->mmco));
816  h->mmco_index = mmco_index;
817  } else if (!first_slice && mmco_index >= 0 &&
818  (mmco_index != h->mmco_index ||
819  check_opcodes(h->mmco, mmco_temp, mmco_index))) {
821  "Inconsistent MMCO state between slices [%d, %d]\n",
822  mmco_index, h->mmco_index);
823  return AVERROR_INVALIDDATA;
824  }
825 
826  return 0;
827 }