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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 <inttypes.h>
29 
30 #include "libavutil/avassert.h"
31 #include "internal.h"
32 #include "avcodec.h"
33 #include "h264.h"
34 #include "golomb.h"
35 #include "mpegutils.h"
36 
37 #include <assert.h>
38 
39 #define COPY_PICTURE(dst, src) \
40 do {\
41  *(dst) = *(src);\
42  (dst)->f.extended_data = (dst)->f.data;\
43  (dst)->tf.f = &(dst)->f;\
44 } while (0)
45 
46 
47 static void pic_as_field(H264Picture *pic, const int parity){
48  int i;
49  for (i = 0; i < 4; ++i) {
50  if (parity == PICT_BOTTOM_FIELD)
51  pic->f.data[i] += pic->f.linesize[i];
52  pic->reference = parity;
53  pic->f.linesize[i] *= 2;
54  }
55  pic->poc= pic->field_poc[parity == PICT_BOTTOM_FIELD];
56 }
57 
58 static int split_field_copy(H264Picture *dest, H264Picture *src, int parity, int id_add)
59 {
60  int match = !!(src->reference & parity);
61 
62  if (match) {
63  COPY_PICTURE(dest, src);
64  if (parity != PICT_FRAME) {
65  pic_as_field(dest, parity);
66  dest->pic_id *= 2;
67  dest->pic_id += id_add;
68  }
69  }
70 
71  return match;
72 }
73 
74 static int build_def_list(H264Picture *def, int def_len,
75  H264Picture **in, int len, int is_long, int sel)
76 {
77  int i[2] = { 0 };
78  int index = 0;
79 
80  while (i[0] < len || i[1] < len) {
81  while (i[0] < len && !(in[i[0]] && (in[i[0]]->reference & sel)))
82  i[0]++;
83  while (i[1] < len && !(in[i[1]] && (in[i[1]]->reference & (sel ^ 3))))
84  i[1]++;
85  if (i[0] < len) {
86  av_assert0(index < def_len);
87  in[i[0]]->pic_id = is_long ? i[0] : in[i[0]]->frame_num;
88  split_field_copy(&def[index++], in[i[0]++], sel, 1);
89  }
90  if (i[1] < len) {
91  av_assert0(index < def_len);
92  in[i[1]]->pic_id = is_long ? i[1] : in[i[1]]->frame_num;
93  split_field_copy(&def[index++], in[i[1]++], sel ^ 3, 0);
94  }
95  }
96 
97  return index;
98 }
99 
100 static int add_sorted(H264Picture **sorted, H264Picture **src, int len, int limit, int dir)
101 {
102  int i, best_poc;
103  int out_i = 0;
104 
105  for (;;) {
106  best_poc = dir ? INT_MIN : INT_MAX;
107 
108  for (i = 0; i < len; i++) {
109  const int poc = src[i]->poc;
110  if (((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)) {
111  best_poc = poc;
112  sorted[out_i] = src[i];
113  }
114  }
115  if (best_poc == (dir ? INT_MIN : INT_MAX))
116  break;
117  limit = sorted[out_i++]->poc - dir;
118  }
119  return out_i;
120 }
121 
123 {
124  int i, len;
125 
126  if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
127  H264Picture *sorted[32];
128  int cur_poc, list;
129  int lens[2];
130 
131  if (FIELD_PICTURE(h))
133  else
134  cur_poc = h->cur_pic_ptr->poc;
135 
136  for (list = 0; list < 2; list++) {
137  len = add_sorted(sorted, h->short_ref, h->short_ref_count, cur_poc, 1 ^ list);
138  len += add_sorted(sorted + len, h->short_ref, h->short_ref_count, cur_poc, 0 ^ list);
139  av_assert0(len <= 32);
140 
142  sorted, len, 0, h->picture_structure);
143  len += build_def_list(h->default_ref_list[list] + len,
144  FF_ARRAY_ELEMS(h->default_ref_list[0]) - len,
145  h->long_ref, 16, 1, h->picture_structure);
146  av_assert0(len <= 32);
147 
148  if (len < h->ref_count[list])
149  memset(&h->default_ref_list[list][len], 0, sizeof(H264Picture) * (h->ref_count[list] - len));
150  lens[list] = len;
151  }
152 
153  if (lens[0] == lens[1] && lens[1] > 1) {
154  for (i = 0; i < lens[0] &&
155  h->default_ref_list[0][i].f.buf[0]->buffer ==
156  h->default_ref_list[1][i].f.buf[0]->buffer; i++);
157  if (i == lens[0]) {
158  H264Picture tmp;
159  COPY_PICTURE(&tmp, &h->default_ref_list[1][0]);
160  COPY_PICTURE(&h->default_ref_list[1][0], &h->default_ref_list[1][1]);
161  COPY_PICTURE(&h->default_ref_list[1][1], &tmp);
162  }
163  }
164  } else {
167  len += build_def_list(h->default_ref_list[0] + len,
168  FF_ARRAY_ELEMS(h->default_ref_list[0]) - len,
169  h-> long_ref, 16, 1, h->picture_structure);
170  av_assert0(len <= 32);
171 
172  if (len < h->ref_count[0])
173  memset(&h->default_ref_list[0][len], 0, sizeof(H264Picture) * (h->ref_count[0] - len));
174  }
175 #ifdef TRACE
176  for (i = 0; i < h->ref_count[0]; i++) {
177  tprintf(h->avctx, "List0: %s fn:%d 0x%p\n",
178  (h->default_ref_list[0][i].long_ref ? "LT" : "ST"),
179  h->default_ref_list[0][i].pic_id,
180  h->default_ref_list[0][i].f.data[0]);
181  }
182  if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
183  for (i = 0; i < h->ref_count[1]; i++) {
184  tprintf(h->avctx, "List1: %s fn:%d 0x%p\n",
185  (h->default_ref_list[1][i].long_ref ? "LT" : "ST"),
186  h->default_ref_list[1][i].pic_id,
187  h->default_ref_list[1][i].f.data[0]);
188  }
189  }
190 #endif
191  return 0;
192 }
193 
194 static void print_short_term(H264Context *h);
195 static void print_long_term(H264Context *h);
196 
197 /**
198  * Extract structure information about the picture described by pic_num in
199  * the current decoding context (frame or field). Note that pic_num is
200  * picture number without wrapping (so, 0<=pic_num<max_pic_num).
201  * @param pic_num picture number for which to extract structure information
202  * @param structure one of PICT_XXX describing structure of picture
203  * with pic_num
204  * @return frame number (short term) or long term index of picture
205  * described by pic_num
206  */
207 static int pic_num_extract(H264Context *h, int pic_num, int *structure)
208 {
209  *structure = h->picture_structure;
210  if (FIELD_PICTURE(h)) {
211  if (!(pic_num & 1))
212  /* opposite field */
213  *structure ^= PICT_FRAME;
214  pic_num >>= 1;
215  }
216 
217  return pic_num;
218 }
219 
221 {
222  int list, index, pic_structure, i;
223 
224  print_short_term(h);
225  print_long_term(h);
226 
227  for (list = 0; list < h->list_count; list++) {
228  for (i = 0; i < h->ref_count[list]; i++)
229  COPY_PICTURE(&h->ref_list[list][i], &h->default_ref_list[list][i]);
230 
231  if (get_bits1(&h->gb)) { // ref_pic_list_modification_flag_l[01]
232  int pred = h->curr_pic_num;
233 
234  for (index = 0; ; index++) {
235  unsigned int modification_of_pic_nums_idc = get_ue_golomb_31(&h->gb);
236  unsigned int pic_id;
237  int i;
238  H264Picture *ref = NULL;
239 
240  if (modification_of_pic_nums_idc == 3)
241  break;
242 
243  if (index >= h->ref_count[list]) {
244  av_log(h->avctx, AV_LOG_ERROR, "reference count overflow\n");
245  return -1;
246  }
247 
248  switch (modification_of_pic_nums_idc) {
249  case 0:
250  case 1: {
251  const unsigned int abs_diff_pic_num = get_ue_golomb(&h->gb) + 1;
252  int frame_num;
253 
254  if (abs_diff_pic_num > h->max_pic_num) {
256  "abs_diff_pic_num overflow\n");
257  return AVERROR_INVALIDDATA;
258  }
259 
260  if (modification_of_pic_nums_idc == 0)
261  pred -= abs_diff_pic_num;
262  else
263  pred += abs_diff_pic_num;
264  pred &= h->max_pic_num - 1;
265 
266  frame_num = pic_num_extract(h, pred, &pic_structure);
267 
268  for (i = h->short_ref_count - 1; i >= 0; i--) {
269  ref = h->short_ref[i];
270  assert(ref->reference);
271  assert(!ref->long_ref);
272  if (ref->frame_num == frame_num &&
273  (ref->reference & pic_structure))
274  break;
275  }
276  if (i >= 0)
277  ref->pic_id = pred;
278  break;
279  }
280  case 2: {
281  int long_idx;
282  pic_id = get_ue_golomb(&h->gb); // long_term_pic_idx
283 
284  long_idx = pic_num_extract(h, pic_id, &pic_structure);
285 
286  if (long_idx > 31) {
288  "long_term_pic_idx overflow\n");
289  return AVERROR_INVALIDDATA;
290  }
291  ref = h->long_ref[long_idx];
292  assert(!(ref && !ref->reference));
293  if (ref && (ref->reference & pic_structure)) {
294  ref->pic_id = pic_id;
295  assert(ref->long_ref);
296  i = 0;
297  } else {
298  i = -1;
299  }
300  break;
301  }
302  default:
304  "illegal modification_of_pic_nums_idc %u\n",
305  modification_of_pic_nums_idc);
306  return AVERROR_INVALIDDATA;
307  }
308 
309  if (i < 0) {
311  "reference picture missing during reorder\n");
312  memset(&h->ref_list[list][index], 0, sizeof(H264Picture)); // FIXME
313  } else {
314  for (i = index; i + 1 < h->ref_count[list]; i++) {
315  if (ref->long_ref == h->ref_list[list][i].long_ref &&
316  ref->pic_id == h->ref_list[list][i].pic_id)
317  break;
318  }
319  for (; i > index; i--) {
320  COPY_PICTURE(&h->ref_list[list][i], &h->ref_list[list][i - 1]);
321  }
322  COPY_PICTURE(&h->ref_list[list][index], ref);
323  if (FIELD_PICTURE(h)) {
324  pic_as_field(&h->ref_list[list][index], pic_structure);
325  }
326  }
327  }
328  }
329  }
330  for (list = 0; list < h->list_count; list++) {
331  for (index = 0; index < h->ref_count[list]; index++) {
332  if ( !h->ref_list[list][index].f.buf[0]
333  || (!FIELD_PICTURE(h) && (h->ref_list[list][index].reference&3) != 3)) {
334  int i;
335  av_log(h->avctx, AV_LOG_ERROR, "Missing reference picture, default is %d\n", h->default_ref_list[list][0].poc);
336  for (i = 0; i < FF_ARRAY_ELEMS(h->last_pocs); i++)
337  h->last_pocs[i] = INT_MIN;
338  if (h->default_ref_list[list][0].f.buf[0]
339  && !(!FIELD_PICTURE(h) && (h->default_ref_list[list][0].reference&3) != 3))
340  COPY_PICTURE(&h->ref_list[list][index], &h->default_ref_list[list][0]);
341  else
342  return -1;
343  }
344  av_assert0(av_buffer_get_ref_count(h->ref_list[list][index].f.buf[0]) > 0);
345  }
346  }
347 
348  return 0;
349 }
350 
352 {
353  int list, i, j;
354  for (list = 0; list < h->list_count; list++) {
355  for (i = 0; i < h->ref_count[list]; i++) {
356  H264Picture *frame = &h->ref_list[list][i];
357  H264Picture *field = &h->ref_list[list][16 + 2 * i];
358  COPY_PICTURE(field, frame);
359  for (j = 0; j < 3; j++)
360  field[0].f.linesize[j] <<= 1;
361  field[0].reference = PICT_TOP_FIELD;
362  field[0].poc = field[0].field_poc[0];
363  COPY_PICTURE(field + 1, field);
364  for (j = 0; j < 3; j++)
365  field[1].f.data[j] += frame->f.linesize[j];
366  field[1].reference = PICT_BOTTOM_FIELD;
367  field[1].poc = field[1].field_poc[1];
368 
369  h->luma_weight[16 + 2 * i][list][0] = h->luma_weight[16 + 2 * i + 1][list][0] = h->luma_weight[i][list][0];
370  h->luma_weight[16 + 2 * i][list][1] = h->luma_weight[16 + 2 * i + 1][list][1] = h->luma_weight[i][list][1];
371  for (j = 0; j < 2; j++) {
372  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];
373  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];
374  }
375  }
376  }
377 }
378 
379 /**
380  * Mark a picture as no longer needed for reference. The refmask
381  * argument allows unreferencing of individual fields or the whole frame.
382  * If the picture becomes entirely unreferenced, but is being held for
383  * display purposes, it is marked as such.
384  * @param refmask mask of fields to unreference; the mask is bitwise
385  * anded with the reference marking of pic
386  * @return non-zero if pic becomes entirely unreferenced (except possibly
387  * for display purposes) zero if one of the fields remains in
388  * reference
389  */
390 static inline int unreference_pic(H264Context *h, H264Picture *pic, int refmask)
391 {
392  int i;
393  if (pic->reference &= refmask) {
394  return 0;
395  } else {
396  for(i = 0; h->delayed_pic[i]; i++)
397  if(pic == h->delayed_pic[i]){
398  pic->reference = DELAYED_PIC_REF;
399  break;
400  }
401  return 1;
402  }
403 }
404 
405 /**
406  * Find a H264Picture in the short term reference list by frame number.
407  * @param frame_num frame number to search for
408  * @param idx the index into h->short_ref where returned picture is found
409  * undefined if no picture found.
410  * @return pointer to the found picture, or NULL if no pic with the provided
411  * frame number is found
412  */
413 static H264Picture *find_short(H264Context *h, int frame_num, int *idx)
414 {
415  int i;
416 
417  for (i = 0; i < h->short_ref_count; i++) {
418  H264Picture *pic = h->short_ref[i];
419  if (h->avctx->debug & FF_DEBUG_MMCO)
420  av_log(h->avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
421  if (pic->frame_num == frame_num) {
422  *idx = i;
423  return pic;
424  }
425  }
426  return NULL;
427 }
428 
429 /**
430  * Remove a picture from the short term reference list by its index in
431  * that list. This does no checking on the provided index; it is assumed
432  * to be valid. Other list entries are shifted down.
433  * @param i index into h->short_ref of picture to remove.
434  */
435 static void remove_short_at_index(H264Context *h, int i)
436 {
437  assert(i >= 0 && i < h->short_ref_count);
438  h->short_ref[i] = NULL;
439  if (--h->short_ref_count)
440  memmove(&h->short_ref[i], &h->short_ref[i + 1],
441  (h->short_ref_count - i) * sizeof(H264Picture*));
442 }
443 
444 /**
445  *
446  * @return the removed picture or NULL if an error occurs
447  */
448 static H264Picture *remove_short(H264Context *h, int frame_num, int ref_mask)
449 {
450  H264Picture *pic;
451  int i;
452 
453  if (h->avctx->debug & FF_DEBUG_MMCO)
454  av_log(h->avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
455 
456  pic = find_short(h, frame_num, &i);
457  if (pic) {
458  if (unreference_pic(h, pic, ref_mask))
459  remove_short_at_index(h, i);
460  }
461 
462  return pic;
463 }
464 
465 /**
466  * Remove a picture from the long term reference list by its index in
467  * that list.
468  * @return the removed picture or NULL if an error occurs
469  */
470 static H264Picture *remove_long(H264Context *h, int i, int ref_mask)
471 {
472  H264Picture *pic;
473 
474  pic = h->long_ref[i];
475  if (pic) {
476  if (unreference_pic(h, pic, ref_mask)) {
477  assert(h->long_ref[i]->long_ref == 1);
478  h->long_ref[i]->long_ref = 0;
479  h->long_ref[i] = NULL;
480  h->long_ref_count--;
481  }
482  }
483 
484  return pic;
485 }
486 
488 {
489  int i;
490 
491  for (i = 0; i < 16; i++) {
492  remove_long(h, i, 0);
493  }
494  assert(h->long_ref_count == 0);
495 
497  if (h->short_ref_count)
499 
500  for (i = 0; i < h->short_ref_count; i++) {
501  unreference_pic(h, h->short_ref[i], 0);
502  h->short_ref[i] = NULL;
503  }
504  h->short_ref_count = 0;
505 
506  memset(h->default_ref_list, 0, sizeof(h->default_ref_list));
507  memset(h->ref_list, 0, sizeof(h->ref_list));
508 }
509 
510 /**
511  * print short term list
512  */
514 {
515  uint32_t i;
516  if (h->avctx->debug & FF_DEBUG_MMCO) {
517  av_log(h->avctx, AV_LOG_DEBUG, "short term list:\n");
518  for (i = 0; i < h->short_ref_count; i++) {
519  H264Picture *pic = h->short_ref[i];
520  av_log(h->avctx, AV_LOG_DEBUG, "%"PRIu32" fn:%d poc:%d %p\n",
521  i, pic->frame_num, pic->poc, pic->f.data[0]);
522  }
523  }
524 }
525 
526 /**
527  * print long term list
528  */
530 {
531  uint32_t i;
532  if (h->avctx->debug & FF_DEBUG_MMCO) {
533  av_log(h->avctx, AV_LOG_DEBUG, "long term list:\n");
534  for (i = 0; i < 16; i++) {
535  H264Picture *pic = h->long_ref[i];
536  if (pic) {
537  av_log(h->avctx, AV_LOG_DEBUG, "%"PRIu32" fn:%d poc:%d %p\n",
538  i, pic->frame_num, pic->poc, pic->f.data[0]);
539  }
540  }
541  }
542 }
543 
544 static int check_opcodes(MMCO *mmco1, MMCO *mmco2, int n_mmcos)
545 {
546  int i;
547 
548  for (i = 0; i < n_mmcos; i++) {
549  if (mmco1[i].opcode != mmco2[i].opcode) {
550  av_log(NULL, AV_LOG_ERROR, "MMCO opcode [%d, %d] at %d mismatches between slices\n",
551  mmco1[i].opcode, mmco2[i].opcode, i);
552  return -1;
553  }
554  }
555 
556  return 0;
557 }
558 
560 {
561  MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = first_slice ? h->mmco : mmco_temp;
562  int mmco_index = 0, i = 0;
563 
564  if (h->short_ref_count &&
566  !(FIELD_PICTURE(h) && !h->first_field && h->cur_pic_ptr->reference)) {
567  mmco[0].opcode = MMCO_SHORT2UNUSED;
568  mmco[0].short_pic_num = h->short_ref[h->short_ref_count - 1]->frame_num;
569  mmco_index = 1;
570  if (FIELD_PICTURE(h)) {
571  mmco[0].short_pic_num *= 2;
572  mmco[1].opcode = MMCO_SHORT2UNUSED;
573  mmco[1].short_pic_num = mmco[0].short_pic_num + 1;
574  mmco_index = 2;
575  }
576  }
577 
578  if (first_slice) {
579  h->mmco_index = mmco_index;
580  } else if (!first_slice && mmco_index >= 0 &&
581  (mmco_index != h->mmco_index ||
582  (i = check_opcodes(h->mmco, mmco_temp, mmco_index)))) {
584  "Inconsistent MMCO state between slices [%d, %d]\n",
585  mmco_index, h->mmco_index);
586  return AVERROR_INVALIDDATA;
587  }
588  return 0;
589 }
590 
591 int ff_h264_execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count)
592 {
593  int i, av_uninit(j);
594  int pps_count;
595  int current_ref_assigned = 0, err = 0;
596  H264Picture *av_uninit(pic);
597 
598  if ((h->avctx->debug & FF_DEBUG_MMCO) && mmco_count == 0)
599  av_log(h->avctx, AV_LOG_DEBUG, "no mmco here\n");
600 
601  for (i = 0; i < mmco_count; i++) {
602  int av_uninit(structure), av_uninit(frame_num);
603  if (h->avctx->debug & FF_DEBUG_MMCO)
604  av_log(h->avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode,
605  h->mmco[i].short_pic_num, h->mmco[i].long_arg);
606 
607  if (mmco[i].opcode == MMCO_SHORT2UNUSED ||
608  mmco[i].opcode == MMCO_SHORT2LONG) {
609  frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
610  pic = find_short(h, frame_num, &j);
611  if (!pic) {
612  if (mmco[i].opcode != MMCO_SHORT2LONG ||
613  !h->long_ref[mmco[i].long_arg] ||
614  h->long_ref[mmco[i].long_arg]->frame_num != frame_num) {
615  av_log(h->avctx, h->short_ref_count ? AV_LOG_ERROR : AV_LOG_DEBUG, "mmco: unref short failure\n");
616  err = AVERROR_INVALIDDATA;
617  }
618  continue;
619  }
620  }
621 
622  switch (mmco[i].opcode) {
623  case MMCO_SHORT2UNUSED:
624  if (h->avctx->debug & FF_DEBUG_MMCO)
625  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n",
627  remove_short(h, frame_num, structure ^ PICT_FRAME);
628  break;
629  case MMCO_SHORT2LONG:
630  if (h->long_ref[mmco[i].long_arg] != pic)
631  remove_long(h, mmco[i].long_arg, 0);
632 
633  remove_short_at_index(h, j);
634  h->long_ref[ mmco[i].long_arg ] = pic;
635  if (h->long_ref[mmco[i].long_arg]) {
636  h->long_ref[mmco[i].long_arg]->long_ref = 1;
637  h->long_ref_count++;
638  }
639  break;
640  case MMCO_LONG2UNUSED:
641  j = pic_num_extract(h, mmco[i].long_arg, &structure);
642  pic = h->long_ref[j];
643  if (pic) {
644  remove_long(h, j, structure ^ PICT_FRAME);
645  } else if (h->avctx->debug & FF_DEBUG_MMCO)
646  av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
647  break;
648  case MMCO_LONG:
649  // Comment below left from previous code as it is an interresting note.
650  /* First field in pair is in short term list or
651  * at a different long term index.
652  * This is not allowed; see 7.4.3.3, notes 2 and 3.
653  * Report the problem and keep the pair where it is,
654  * and mark this field valid.
655  */
656  if (h->short_ref[0] == h->cur_pic_ptr) {
657  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to short and long at the same time\n");
658  remove_short_at_index(h, 0);
659  }
660 
661  if (h->long_ref[mmco[i].long_arg] != h->cur_pic_ptr) {
662  if (h->cur_pic_ptr->long_ref) {
663  for(j=0; j<16; j++) {
664  if(h->long_ref[j] == h->cur_pic_ptr) {
665  remove_long(h, j, 0);
666  av_log(h->avctx, AV_LOG_ERROR, "mmco: cannot assign current picture to 2 long term references\n");
667  }
668  }
669  }
671  remove_long(h, mmco[i].long_arg, 0);
672 
673  h->long_ref[mmco[i].long_arg] = h->cur_pic_ptr;
674  h->long_ref[mmco[i].long_arg]->long_ref = 1;
675  h->long_ref_count++;
676  }
677 
679  current_ref_assigned = 1;
680  break;
681  case MMCO_SET_MAX_LONG:
682  assert(mmco[i].long_arg <= 16);
683  // just remove the long term which index is greater than new max
684  for (j = mmco[i].long_arg; j < 16; j++) {
685  remove_long(h, j, 0);
686  }
687  break;
688  case MMCO_RESET:
689  while (h->short_ref_count) {
690  remove_short(h, h->short_ref[0]->frame_num, 0);
691  }
692  for (j = 0; j < 16; j++) {
693  remove_long(h, j, 0);
694  }
695  h->frame_num = h->cur_pic_ptr->frame_num = 0;
696  h->mmco_reset = 1;
697  h->cur_pic_ptr->mmco_reset = 1;
698  for (j = 0; j < MAX_DELAYED_PIC_COUNT; j++)
699  h->last_pocs[j] = INT_MIN;
700  break;
701  default: assert(0);
702  }
703  }
704 
705  if (!current_ref_assigned) {
706  /* Second field of complementary field pair; the first field of
707  * which is already referenced. If short referenced, it
708  * should be first entry in short_ref. If not, it must exist
709  * in long_ref; trying to put it on the short list here is an
710  * error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
711  */
712  if (h->short_ref_count && h->short_ref[0] == h->cur_pic_ptr) {
713  /* Just mark the second field valid */
715  } else if (h->cur_pic_ptr->long_ref) {
716  av_log(h->avctx, AV_LOG_ERROR, "illegal short term reference "
717  "assignment for second field "
718  "in complementary field pair "
719  "(first field is long term)\n");
720  err = AVERROR_INVALIDDATA;
721  } else {
722  pic = remove_short(h, h->cur_pic_ptr->frame_num, 0);
723  if (pic) {
724  av_log(h->avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
725  err = AVERROR_INVALIDDATA;
726  }
727 
728  if (h->short_ref_count)
729  memmove(&h->short_ref[1], &h->short_ref[0],
730  h->short_ref_count * sizeof(H264Picture*));
731 
732  h->short_ref[0] = h->cur_pic_ptr;
733  h->short_ref_count++;
735  }
736  }
737 
738  if (h->long_ref_count + h->short_ref_count > FFMAX(h->sps.ref_frame_count, 1)) {
739 
740  /* We have too many reference frames, probably due to corrupted
741  * stream. Need to discard one frame. Prevents overrun of the
742  * short_ref and long_ref buffers.
743  */
745  "number of reference frames (%d+%d) exceeds max (%d; probably "
746  "corrupt input), discarding one\n",
748  err = AVERROR_INVALIDDATA;
749 
750  if (h->long_ref_count && !h->short_ref_count) {
751  for (i = 0; i < 16; ++i)
752  if (h->long_ref[i])
753  break;
754 
755  assert(i < 16);
756  remove_long(h, i, 0);
757  } else {
758  pic = h->short_ref[h->short_ref_count - 1];
759  remove_short(h, pic->frame_num, 0);
760  }
761  }
762 
763  for (i = 0; i<h->short_ref_count; i++) {
764  pic = h->short_ref[i];
765  if (pic->invalid_gap) {
766  int d = (h->cur_pic_ptr->frame_num - pic->frame_num) & ((1 << h->sps.log2_max_frame_num)-1);
767  if (d > h->sps.ref_frame_count)
768  remove_short(h, pic->frame_num, 0);
769  }
770  }
771 
772  print_short_term(h);
773  print_long_term(h);
774 
775  pps_count = 0;
776  for (i = 0; i < FF_ARRAY_ELEMS(h->pps_buffers); i++)
777  pps_count += !!h->pps_buffers[i];
778 
779  if ( err >= 0
780  && h->long_ref_count==0
781  && (h->short_ref_count<=2 || h->pps.ref_count[0] <= 1 && h->pps.ref_count[1] <= 1 && pps_count == 1)
782  && h->pps.ref_count[0]<=2 + (h->picture_structure != PICT_FRAME) + (2*!h->has_recovery_point)
784  h->cur_pic_ptr->recovered |= 1;
785  if(!h->avctx->has_b_frames)
787  }
788 
789  return (h->avctx->err_recognition & AV_EF_EXPLODE) ? err : 0;
790 }
791 
793  int first_slice)
794 {
795  int i, ret;
796  MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = mmco_temp;
797  int mmco_index = 0;
798 
799  if (h->nal_unit_type == NAL_IDR_SLICE) { // FIXME fields
800  skip_bits1(gb); // broken_link
801  if (get_bits1(gb)) {
802  mmco[0].opcode = MMCO_LONG;
803  mmco[0].long_arg = 0;
804  mmco_index = 1;
805  }
806  } else {
807  if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
808  for (i = 0; i < MAX_MMCO_COUNT; i++) {
809  MMCOOpcode opcode = get_ue_golomb_31(gb);
810 
811  mmco[i].opcode = opcode;
812  if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) {
813  mmco[i].short_pic_num =
814  (h->curr_pic_num - get_ue_golomb(gb) - 1) &
815  (h->max_pic_num - 1);
816 #if 0
817  if (mmco[i].short_pic_num >= h->short_ref_count ||
818  !h->short_ref[mmco[i].short_pic_num]) {
819  av_log(s->avctx, AV_LOG_ERROR,
820  "illegal short ref in memory management control "
821  "operation %d\n", mmco);
822  return -1;
823  }
824 #endif
825  }
826  if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
827  opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG) {
828  unsigned int long_arg = get_ue_golomb_31(gb);
829  if (long_arg >= 32 ||
830  (long_arg >= 16 && !(opcode == MMCO_SET_MAX_LONG &&
831  long_arg == 16) &&
832  !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE(h)))) {
834  "illegal long ref in memory management control "
835  "operation %d\n", opcode);
836  return -1;
837  }
838  mmco[i].long_arg = long_arg;
839  }
840 
841  if (opcode > (unsigned) MMCO_LONG) {
843  "illegal memory management control operation %d\n",
844  opcode);
845  return -1;
846  }
847  if (opcode == MMCO_END)
848  break;
849  }
850  mmco_index = i;
851  } else {
852  if (first_slice) {
853  ret = ff_generate_sliding_window_mmcos(h, first_slice);
854  if (ret < 0 && h->avctx->err_recognition & AV_EF_EXPLODE)
855  return ret;
856  }
857  mmco_index = -1;
858  }
859  }
860 
861  if (first_slice && mmco_index != -1) {
862  memcpy(h->mmco, mmco_temp, sizeof(h->mmco));
863  h->mmco_index = mmco_index;
864  } else if (!first_slice && mmco_index >= 0 &&
865  (mmco_index != h->mmco_index ||
866  check_opcodes(h->mmco, mmco_temp, mmco_index))) {
868  "Inconsistent MMCO state between slices [%d, %d]\n",
869  mmco_index, h->mmco_index);
870  return AVERROR_INVALIDDATA;
871  }
872 
873  return 0;
874 }