ed715c6b03153bc87db037af8afd3fb0ec0fbe7c
[libav.git] / libavcodec / h264_refs.c
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 "internal.h"
29 #include "dsputil.h"
30 #include "avcodec.h"
31 #include "h264.h"
32 #include "golomb.h"
33
34 //#undef NDEBUG
35 #include <assert.h>
36
37
38 static void pic_as_field(Picture *pic, const int parity){
39 int i;
40 for (i = 0; i < 4; ++i) {
41 if (parity == PICT_BOTTOM_FIELD)
42 pic->data[i] += pic->linesize[i];
43 pic->reference = parity;
44 pic->linesize[i] *= 2;
45 }
46 pic->poc= pic->field_poc[parity == PICT_BOTTOM_FIELD];
47 }
48
49 static int split_field_copy(Picture *dest, Picture *src,
50 int parity, int id_add){
51 int match = !!(src->reference & parity);
52
53 if (match) {
54 *dest = *src;
55 if(parity != PICT_FRAME){
56 pic_as_field(dest, parity);
57 dest->pic_id *= 2;
58 dest->pic_id += id_add;
59 }
60 }
61
62 return match;
63 }
64
65 static int build_def_list(Picture *def, Picture **in, int len, int is_long, int sel){
66 int i[2]={0};
67 int index=0;
68
69 while(i[0]<len || i[1]<len){
70 while(i[0]<len && !(in[ i[0] ] && (in[ i[0] ]->reference & sel)))
71 i[0]++;
72 while(i[1]<len && !(in[ i[1] ] && (in[ i[1] ]->reference & (sel^3))))
73 i[1]++;
74 if(i[0] < len){
75 in[ i[0] ]->pic_id= is_long ? i[0] : in[ i[0] ]->frame_num;
76 split_field_copy(&def[index++], in[ i[0]++ ], sel , 1);
77 }
78 if(i[1] < len){
79 in[ i[1] ]->pic_id= is_long ? i[1] : in[ i[1] ]->frame_num;
80 split_field_copy(&def[index++], in[ i[1]++ ], sel^3, 0);
81 }
82 }
83
84 return index;
85 }
86
87 static int add_sorted(Picture **sorted, Picture **src, int len, int limit, int dir){
88 int i, best_poc;
89 int out_i= 0;
90
91 for(;;){
92 best_poc= dir ? INT_MIN : INT_MAX;
93
94 for(i=0; i<len; i++){
95 const int poc= src[i]->poc;
96 if(((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)){
97 best_poc= poc;
98 sorted[out_i]= src[i];
99 }
100 }
101 if(best_poc == (dir ? INT_MIN : INT_MAX))
102 break;
103 limit= sorted[out_i++]->poc - dir;
104 }
105 return out_i;
106 }
107
108 int ff_h264_fill_default_ref_list(H264Context *h){
109 MpegEncContext * const s = &h->s;
110 int i, len;
111
112 if(h->slice_type_nos==FF_B_TYPE){
113 Picture *sorted[32];
114 int cur_poc, list;
115 int lens[2];
116
117 if(FIELD_PICTURE)
118 cur_poc= s->current_picture_ptr->field_poc[ s->picture_structure == PICT_BOTTOM_FIELD ];
119 else
120 cur_poc= s->current_picture_ptr->poc;
121
122 for(list= 0; list<2; list++){
123 len= add_sorted(sorted , h->short_ref, h->short_ref_count, cur_poc, 1^list);
124 len+=add_sorted(sorted+len, h->short_ref, h->short_ref_count, cur_poc, 0^list);
125 assert(len<=32);
126 len= build_def_list(h->default_ref_list[list] , sorted , len, 0, s->picture_structure);
127 len+=build_def_list(h->default_ref_list[list]+len, h->long_ref, 16 , 1, s->picture_structure);
128 assert(len<=32);
129
130 if(len < h->ref_count[list])
131 memset(&h->default_ref_list[list][len], 0, sizeof(Picture)*(h->ref_count[list] - len));
132 lens[list]= len;
133 }
134
135 if(lens[0] == lens[1] && lens[1] > 1){
136 for(i=0; h->default_ref_list[0][i].data[0] == h->default_ref_list[1][i].data[0] && i<lens[0]; i++);
137 if(i == lens[0])
138 FFSWAP(Picture, h->default_ref_list[1][0], h->default_ref_list[1][1]);
139 }
140 }else{
141 len = build_def_list(h->default_ref_list[0] , h->short_ref, h->short_ref_count, 0, s->picture_structure);
142 len+= build_def_list(h->default_ref_list[0]+len, h-> long_ref, 16 , 1, s->picture_structure);
143 assert(len <= 32);
144 if(len < h->ref_count[0])
145 memset(&h->default_ref_list[0][len], 0, sizeof(Picture)*(h->ref_count[0] - len));
146 }
147 #ifdef TRACE
148 for (i=0; i<h->ref_count[0]; i++) {
149 tprintf(h->s.avctx, "List0: %s fn:%d 0x%p\n", (h->default_ref_list[0][i].long_ref ? "LT" : "ST"), h->default_ref_list[0][i].pic_id, h->default_ref_list[0][i].data[0]);
150 }
151 if(h->slice_type_nos==FF_B_TYPE){
152 for (i=0; i<h->ref_count[1]; i++) {
153 tprintf(h->s.avctx, "List1: %s fn:%d 0x%p\n", (h->default_ref_list[1][i].long_ref ? "LT" : "ST"), h->default_ref_list[1][i].pic_id, h->default_ref_list[1][i].data[0]);
154 }
155 }
156 #endif
157 return 0;
158 }
159
160 static void print_short_term(H264Context *h);
161 static void print_long_term(H264Context *h);
162
163 /**
164 * Extract structure information about the picture described by pic_num in
165 * the current decoding context (frame or field). Note that pic_num is
166 * picture number without wrapping (so, 0<=pic_num<max_pic_num).
167 * @param pic_num picture number for which to extract structure information
168 * @param structure one of PICT_XXX describing structure of picture
169 * with pic_num
170 * @return frame number (short term) or long term index of picture
171 * described by pic_num
172 */
173 static int pic_num_extract(H264Context *h, int pic_num, int *structure){
174 MpegEncContext * const s = &h->s;
175
176 *structure = s->picture_structure;
177 if(FIELD_PICTURE){
178 if (!(pic_num & 1))
179 /* opposite field */
180 *structure ^= PICT_FRAME;
181 pic_num >>= 1;
182 }
183
184 return pic_num;
185 }
186
187 int ff_h264_decode_ref_pic_list_reordering(H264Context *h){
188 MpegEncContext * const s = &h->s;
189 int list, index, pic_structure;
190
191 print_short_term(h);
192 print_long_term(h);
193
194 for(list=0; list<h->list_count; list++){
195 memcpy(h->ref_list[list], h->default_ref_list[list], sizeof(Picture)*h->ref_count[list]);
196
197 if(get_bits1(&s->gb)){
198 int pred= h->curr_pic_num;
199
200 for(index=0; ; index++){
201 unsigned int reordering_of_pic_nums_idc= get_ue_golomb_31(&s->gb);
202 unsigned int pic_id;
203 int i;
204 Picture *ref = NULL;
205
206 if(reordering_of_pic_nums_idc==3)
207 break;
208
209 if(index >= h->ref_count[list]){
210 av_log(h->s.avctx, AV_LOG_ERROR, "reference count overflow\n");
211 return -1;
212 }
213
214 if(reordering_of_pic_nums_idc<3){
215 if(reordering_of_pic_nums_idc<2){
216 const unsigned int abs_diff_pic_num= get_ue_golomb(&s->gb) + 1;
217 int frame_num;
218
219 if(abs_diff_pic_num > h->max_pic_num){
220 av_log(h->s.avctx, AV_LOG_ERROR, "abs_diff_pic_num overflow\n");
221 return -1;
222 }
223
224 if(reordering_of_pic_nums_idc == 0) pred-= abs_diff_pic_num;
225 else pred+= abs_diff_pic_num;
226 pred &= h->max_pic_num - 1;
227
228 frame_num = pic_num_extract(h, pred, &pic_structure);
229
230 for(i= h->short_ref_count-1; i>=0; i--){
231 ref = h->short_ref[i];
232 assert(ref->reference);
233 assert(!ref->long_ref);
234 if(
235 ref->frame_num == frame_num &&
236 (ref->reference & pic_structure)
237 )
238 break;
239 }
240 if(i>=0)
241 ref->pic_id= pred;
242 }else{
243 int long_idx;
244 pic_id= get_ue_golomb(&s->gb); //long_term_pic_idx
245
246 long_idx= pic_num_extract(h, pic_id, &pic_structure);
247
248 if(long_idx>31){
249 av_log(h->s.avctx, AV_LOG_ERROR, "long_term_pic_idx overflow\n");
250 return -1;
251 }
252 ref = h->long_ref[long_idx];
253 assert(!(ref && !ref->reference));
254 if(ref && (ref->reference & pic_structure)){
255 ref->pic_id= pic_id;
256 assert(ref->long_ref);
257 i=0;
258 }else{
259 i=-1;
260 }
261 }
262
263 if (i < 0) {
264 av_log(h->s.avctx, AV_LOG_ERROR, "reference picture missing during reorder\n");
265 memset(&h->ref_list[list][index], 0, sizeof(Picture)); //FIXME
266 } else {
267 for(i=index; i+1<h->ref_count[list]; i++){
268 if(ref->long_ref == h->ref_list[list][i].long_ref && ref->pic_id == h->ref_list[list][i].pic_id)
269 break;
270 }
271 for(; i > index; i--){
272 h->ref_list[list][i]= h->ref_list[list][i-1];
273 }
274 h->ref_list[list][index]= *ref;
275 if (FIELD_PICTURE){
276 pic_as_field(&h->ref_list[list][index], pic_structure);
277 }
278 }
279 }else{
280 av_log(h->s.avctx, AV_LOG_ERROR, "illegal reordering_of_pic_nums_idc\n");
281 return -1;
282 }
283 }
284 }
285 }
286 for(list=0; list<h->list_count; list++){
287 for(index= 0; index < h->ref_count[list]; index++){
288 if(!h->ref_list[list][index].data[0]){
289 av_log(h->s.avctx, AV_LOG_ERROR, "Missing reference picture\n");
290 if(h->default_ref_list[list][0].data[0])
291 h->ref_list[list][index]= h->default_ref_list[list][0];
292 else
293 return -1;
294 }
295 }
296 }
297
298 return 0;
299 }
300
301 void ff_h264_fill_mbaff_ref_list(H264Context *h){
302 int list, i, j;
303 for(list=0; list<2; list++){ //FIXME try list_count
304 for(i=0; i<h->ref_count[list]; i++){
305 Picture *frame = &h->ref_list[list][i];
306 Picture *field = &h->ref_list[list][16+2*i];
307 field[0] = *frame;
308 for(j=0; j<3; j++)
309 field[0].linesize[j] <<= 1;
310 field[0].reference = PICT_TOP_FIELD;
311 field[0].poc= field[0].field_poc[0];
312 field[1] = field[0];
313 for(j=0; j<3; j++)
314 field[1].data[j] += frame->linesize[j];
315 field[1].reference = PICT_BOTTOM_FIELD;
316 field[1].poc= field[1].field_poc[1];
317
318 h->luma_weight[16+2*i][list][0] = h->luma_weight[16+2*i+1][list][0] = h->luma_weight[i][list][0];
319 h->luma_weight[16+2*i][list][1] = h->luma_weight[16+2*i+1][list][1] = h->luma_weight[i][list][1];
320 for(j=0; j<2; j++){
321 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];
322 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];
323 }
324 }
325 }
326 }
327
328 /**
329 * Mark a picture as no longer needed for reference. The refmask
330 * argument allows unreferencing of individual fields or the whole frame.
331 * If the picture becomes entirely unreferenced, but is being held for
332 * display purposes, it is marked as such.
333 * @param refmask mask of fields to unreference; the mask is bitwise
334 * anded with the reference marking of pic
335 * @return non-zero if pic becomes entirely unreferenced (except possibly
336 * for display purposes) zero if one of the fields remains in
337 * reference
338 */
339 static inline int unreference_pic(H264Context *h, Picture *pic, int refmask){
340 int i;
341 if (pic->reference &= refmask) {
342 return 0;
343 } else {
344 for(i = 0; h->delayed_pic[i]; i++)
345 if(pic == h->delayed_pic[i]){
346 pic->reference=DELAYED_PIC_REF;
347 break;
348 }
349 return 1;
350 }
351 }
352
353 /**
354 * Find a Picture in the short term reference list by frame number.
355 * @param frame_num frame number to search for
356 * @param idx the index into h->short_ref where returned picture is found
357 * undefined if no picture found.
358 * @return pointer to the found picture, or NULL if no pic with the provided
359 * frame number is found
360 */
361 static Picture * find_short(H264Context *h, int frame_num, int *idx){
362 MpegEncContext * const s = &h->s;
363 int i;
364
365 for(i=0; i<h->short_ref_count; i++){
366 Picture *pic= h->short_ref[i];
367 if(s->avctx->debug&FF_DEBUG_MMCO)
368 av_log(h->s.avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
369 if(pic->frame_num == frame_num) {
370 *idx = i;
371 return pic;
372 }
373 }
374 return NULL;
375 }
376
377 /**
378 * Remove a picture from the short term reference list by its index in
379 * that list. This does no checking on the provided index; it is assumed
380 * to be valid. Other list entries are shifted down.
381 * @param i index into h->short_ref of picture to remove.
382 */
383 static void remove_short_at_index(H264Context *h, int i){
384 assert(i >= 0 && i < h->short_ref_count);
385 h->short_ref[i]= NULL;
386 if (--h->short_ref_count)
387 memmove(&h->short_ref[i], &h->short_ref[i+1], (h->short_ref_count - i)*sizeof(Picture*));
388 }
389
390 /**
391 *
392 * @return the removed picture or NULL if an error occurs
393 */
394 static Picture * remove_short(H264Context *h, int frame_num, int ref_mask){
395 MpegEncContext * const s = &h->s;
396 Picture *pic;
397 int i;
398
399 if(s->avctx->debug&FF_DEBUG_MMCO)
400 av_log(h->s.avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
401
402 pic = find_short(h, frame_num, &i);
403 if (pic){
404 if(unreference_pic(h, pic, ref_mask))
405 remove_short_at_index(h, i);
406 }
407
408 return pic;
409 }
410
411 /**
412 * Remove a picture from the long term reference list by its index in
413 * that list.
414 * @return the removed picture or NULL if an error occurs
415 */
416 static Picture * remove_long(H264Context *h, int i, int ref_mask){
417 Picture *pic;
418
419 pic= h->long_ref[i];
420 if (pic){
421 if(unreference_pic(h, pic, ref_mask)){
422 assert(h->long_ref[i]->long_ref == 1);
423 h->long_ref[i]->long_ref= 0;
424 h->long_ref[i]= NULL;
425 h->long_ref_count--;
426 }
427 }
428
429 return pic;
430 }
431
432 void ff_h264_remove_all_refs(H264Context *h){
433 int i;
434
435 for(i=0; i<16; i++){
436 remove_long(h, i, 0);
437 }
438 assert(h->long_ref_count==0);
439
440 for(i=0; i<h->short_ref_count; i++){
441 unreference_pic(h, h->short_ref[i], 0);
442 h->short_ref[i]= NULL;
443 }
444 h->short_ref_count=0;
445 }
446
447 /**
448 * print short term list
449 */
450 static void print_short_term(H264Context *h) {
451 uint32_t i;
452 if(h->s.avctx->debug&FF_DEBUG_MMCO) {
453 av_log(h->s.avctx, AV_LOG_DEBUG, "short term list:\n");
454 for(i=0; i<h->short_ref_count; i++){
455 Picture *pic= h->short_ref[i];
456 av_log(h->s.avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n", i, pic->frame_num, pic->poc, pic->data[0]);
457 }
458 }
459 }
460
461 /**
462 * print long term list
463 */
464 static void print_long_term(H264Context *h) {
465 uint32_t i;
466 if(h->s.avctx->debug&FF_DEBUG_MMCO) {
467 av_log(h->s.avctx, AV_LOG_DEBUG, "long term list:\n");
468 for(i = 0; i < 16; i++){
469 Picture *pic= h->long_ref[i];
470 if (pic) {
471 av_log(h->s.avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n", i, pic->frame_num, pic->poc, pic->data[0]);
472 }
473 }
474 }
475 }
476
477 int ff_h264_execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count){
478 MpegEncContext * const s = &h->s;
479 int i, av_uninit(j);
480 int current_ref_assigned=0;
481 Picture *av_uninit(pic);
482
483 if((s->avctx->debug&FF_DEBUG_MMCO) && mmco_count==0)
484 av_log(h->s.avctx, AV_LOG_DEBUG, "no mmco here\n");
485
486 for(i=0; i<mmco_count; i++){
487 int av_uninit(structure), av_uninit(frame_num);
488 if(s->avctx->debug&FF_DEBUG_MMCO)
489 av_log(h->s.avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode, h->mmco[i].short_pic_num, h->mmco[i].long_arg);
490
491 if( mmco[i].opcode == MMCO_SHORT2UNUSED
492 || mmco[i].opcode == MMCO_SHORT2LONG){
493 frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
494 pic = find_short(h, frame_num, &j);
495 if(!pic){
496 if(mmco[i].opcode != MMCO_SHORT2LONG || !h->long_ref[mmco[i].long_arg]
497 || h->long_ref[mmco[i].long_arg]->frame_num != frame_num)
498 av_log(h->s.avctx, AV_LOG_ERROR, "mmco: unref short failure\n");
499 continue;
500 }
501 }
502
503 switch(mmco[i].opcode){
504 case MMCO_SHORT2UNUSED:
505 if(s->avctx->debug&FF_DEBUG_MMCO)
506 av_log(h->s.avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n", h->mmco[i].short_pic_num, h->short_ref_count);
507 remove_short(h, frame_num, structure ^ PICT_FRAME);
508 break;
509 case MMCO_SHORT2LONG:
510 if (h->long_ref[mmco[i].long_arg] != pic)
511 remove_long(h, mmco[i].long_arg, 0);
512
513 remove_short_at_index(h, j);
514 h->long_ref[ mmco[i].long_arg ]= pic;
515 if (h->long_ref[ mmco[i].long_arg ]){
516 h->long_ref[ mmco[i].long_arg ]->long_ref=1;
517 h->long_ref_count++;
518 }
519 break;
520 case MMCO_LONG2UNUSED:
521 j = pic_num_extract(h, mmco[i].long_arg, &structure);
522 pic = h->long_ref[j];
523 if (pic) {
524 remove_long(h, j, structure ^ PICT_FRAME);
525 } else if(s->avctx->debug&FF_DEBUG_MMCO)
526 av_log(h->s.avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
527 break;
528 case MMCO_LONG:
529 // Comment below left from previous code as it is an interresting note.
530 /* First field in pair is in short term list or
531 * at a different long term index.
532 * This is not allowed; see 7.4.3.3, notes 2 and 3.
533 * Report the problem and keep the pair where it is,
534 * and mark this field valid.
535 */
536
537 if (h->long_ref[mmco[i].long_arg] != s->current_picture_ptr) {
538 remove_long(h, mmco[i].long_arg, 0);
539
540 h->long_ref[ mmco[i].long_arg ]= s->current_picture_ptr;
541 h->long_ref[ mmco[i].long_arg ]->long_ref=1;
542 h->long_ref_count++;
543 }
544
545 s->current_picture_ptr->reference |= s->picture_structure;
546 current_ref_assigned=1;
547 break;
548 case MMCO_SET_MAX_LONG:
549 assert(mmco[i].long_arg <= 16);
550 // just remove the long term which index is greater than new max
551 for(j = mmco[i].long_arg; j<16; j++){
552 remove_long(h, j, 0);
553 }
554 break;
555 case MMCO_RESET:
556 while(h->short_ref_count){
557 remove_short(h, h->short_ref[0]->frame_num, 0);
558 }
559 for(j = 0; j < 16; j++) {
560 remove_long(h, j, 0);
561 }
562 s->current_picture_ptr->poc=
563 s->current_picture_ptr->field_poc[0]=
564 s->current_picture_ptr->field_poc[1]=
565 h->poc_lsb=
566 h->poc_msb=
567 h->frame_num=
568 s->current_picture_ptr->frame_num= 0;
569 s->current_picture_ptr->mmco_reset=1;
570 break;
571 default: assert(0);
572 }
573 }
574
575 if (!current_ref_assigned) {
576 /* Second field of complementary field pair; the first field of
577 * which is already referenced. If short referenced, it
578 * should be first entry in short_ref. If not, it must exist
579 * in long_ref; trying to put it on the short list here is an
580 * error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
581 */
582 if (h->short_ref_count && h->short_ref[0] == s->current_picture_ptr) {
583 /* Just mark the second field valid */
584 s->current_picture_ptr->reference = PICT_FRAME;
585 } else if (s->current_picture_ptr->long_ref) {
586 av_log(h->s.avctx, AV_LOG_ERROR, "illegal short term reference "
587 "assignment for second field "
588 "in complementary field pair "
589 "(first field is long term)\n");
590 } else {
591 pic= remove_short(h, s->current_picture_ptr->frame_num, 0);
592 if(pic){
593 av_log(h->s.avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
594 }
595
596 if(h->short_ref_count)
597 memmove(&h->short_ref[1], &h->short_ref[0], h->short_ref_count*sizeof(Picture*));
598
599 h->short_ref[0]= s->current_picture_ptr;
600 h->short_ref_count++;
601 s->current_picture_ptr->reference |= s->picture_structure;
602 }
603 }
604
605 if (h->long_ref_count + h->short_ref_count > h->sps.ref_frame_count){
606
607 /* We have too many reference frames, probably due to corrupted
608 * stream. Need to discard one frame. Prevents overrun of the
609 * short_ref and long_ref buffers.
610 */
611 av_log(h->s.avctx, AV_LOG_ERROR,
612 "number of reference frames exceeds max (probably "
613 "corrupt input), discarding one\n");
614
615 if (h->long_ref_count && !h->short_ref_count) {
616 for (i = 0; i < 16; ++i)
617 if (h->long_ref[i])
618 break;
619
620 assert(i < 16);
621 remove_long(h, i, 0);
622 } else {
623 pic = h->short_ref[h->short_ref_count - 1];
624 remove_short(h, pic->frame_num, 0);
625 }
626 }
627
628 print_short_term(h);
629 print_long_term(h);
630 return 0;
631 }
632
633 int ff_h264_decode_ref_pic_marking(H264Context *h, GetBitContext *gb){
634 MpegEncContext * const s = &h->s;
635 int i;
636
637 h->mmco_index= 0;
638 if(h->nal_unit_type == NAL_IDR_SLICE){ //FIXME fields
639 s->broken_link= get_bits1(gb) -1;
640 if(get_bits1(gb)){
641 h->mmco[0].opcode= MMCO_LONG;
642 h->mmco[0].long_arg= 0;
643 h->mmco_index= 1;
644 }
645 }else{
646 if(get_bits1(gb)){ // adaptive_ref_pic_marking_mode_flag
647 for(i= 0; i<MAX_MMCO_COUNT; i++) {
648 MMCOOpcode opcode= get_ue_golomb_31(gb);
649
650 h->mmco[i].opcode= opcode;
651 if(opcode==MMCO_SHORT2UNUSED || opcode==MMCO_SHORT2LONG){
652 h->mmco[i].short_pic_num= (h->curr_pic_num - get_ue_golomb(gb) - 1) & (h->max_pic_num - 1);
653 /* if(h->mmco[i].short_pic_num >= h->short_ref_count || h->short_ref[ h->mmco[i].short_pic_num ] == NULL){
654 av_log(s->avctx, AV_LOG_ERROR, "illegal short ref in memory management control operation %d\n", mmco);
655 return -1;
656 }*/
657 }
658 if(opcode==MMCO_SHORT2LONG || opcode==MMCO_LONG2UNUSED || opcode==MMCO_LONG || opcode==MMCO_SET_MAX_LONG){
659 unsigned int long_arg= get_ue_golomb_31(gb);
660 if(long_arg >= 32 || (long_arg >= 16 && !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE))){
661 av_log(h->s.avctx, AV_LOG_ERROR, "illegal long ref in memory management control operation %d\n", opcode);
662 return -1;
663 }
664 h->mmco[i].long_arg= long_arg;
665 }
666
667 if(opcode > (unsigned)MMCO_LONG){
668 av_log(h->s.avctx, AV_LOG_ERROR, "illegal memory management control operation %d\n", opcode);
669 return -1;
670 }
671 if(opcode == MMCO_END)
672 break;
673 }
674 h->mmco_index= i;
675 }else{
676 assert(h->long_ref_count + h->short_ref_count <= h->sps.ref_frame_count);
677
678 if(h->short_ref_count && h->long_ref_count + h->short_ref_count == h->sps.ref_frame_count &&
679 !(FIELD_PICTURE && !s->first_field && s->current_picture_ptr->reference)) {
680 h->mmco[0].opcode= MMCO_SHORT2UNUSED;
681 h->mmco[0].short_pic_num= h->short_ref[ h->short_ref_count - 1 ]->frame_num;
682 h->mmco_index= 1;
683 if (FIELD_PICTURE) {
684 h->mmco[0].short_pic_num *= 2;
685 h->mmco[1].opcode= MMCO_SHORT2UNUSED;
686 h->mmco[1].short_pic_num= h->mmco[0].short_pic_num + 1;
687 h->mmco_index= 2;
688 }
689 }
690 }
691 }
692
693 return 0;
694 }