h263dec.c
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1 /*
2  * H.263 decoder
3  * Copyright (c) 2001 Fabrice Bellard
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
28 #include "libavutil/cpu.h"
29 #include "internal.h"
30 #include "avcodec.h"
31 #include "dsputil.h"
32 #include "mpegvideo.h"
33 #include "h263.h"
34 #include "h263_parser.h"
35 #include "mpeg4video_parser.h"
36 #include "msmpeg4.h"
37 #include "vdpau_internal.h"
38 #include "thread.h"
39 #include "flv.h"
40 #include "mpeg4video.h"
41 
42 //#define DEBUG
43 //#define PRINT_FRAME_TIME
44 
46 {
47  MpegEncContext *s = avctx->priv_data;
48 
49  s->avctx = avctx;
50  s->out_format = FMT_H263;
51 
52  s->width = avctx->coded_width;
53  s->height = avctx->coded_height;
55 
56  // set defaults
58  s->quant_precision=5;
60  s->low_delay= 1;
61  if (avctx->codec->id == AV_CODEC_ID_MSS2)
62  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
63  else
64  avctx->pix_fmt = avctx->get_format(avctx, avctx->codec->pix_fmts);
65  s->unrestricted_mv= 1;
66 
67  /* select sub codec */
68  switch(avctx->codec->id) {
69  case AV_CODEC_ID_H263:
70  s->unrestricted_mv= 0;
72  break;
73  case AV_CODEC_ID_MPEG4:
74  break;
76  s->h263_pred = 1;
77  s->msmpeg4_version=1;
78  break;
80  s->h263_pred = 1;
81  s->msmpeg4_version=2;
82  break;
84  s->h263_pred = 1;
85  s->msmpeg4_version=3;
86  break;
87  case AV_CODEC_ID_WMV1:
88  s->h263_pred = 1;
89  s->msmpeg4_version=4;
90  break;
91  case AV_CODEC_ID_WMV2:
92  s->h263_pred = 1;
93  s->msmpeg4_version=5;
94  break;
95  case AV_CODEC_ID_VC1:
96  case AV_CODEC_ID_WMV3:
99  case AV_CODEC_ID_MSS2:
100  s->h263_pred = 1;
101  s->msmpeg4_version=6;
103  break;
104  case AV_CODEC_ID_H263I:
105  break;
106  case AV_CODEC_ID_FLV1:
107  s->h263_flv = 1;
108  break;
109  default:
110  return -1;
111  }
112  s->codec_id= avctx->codec->id;
113  avctx->hwaccel= ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
114 
115  /* for h263, we allocate the images after having read the header */
116  if (avctx->codec->id != AV_CODEC_ID_H263 && avctx->codec->id != AV_CODEC_ID_MPEG4)
117  if (ff_MPV_common_init(s) < 0)
118  return -1;
119 
121 
122  return 0;
123 }
124 
126 {
127  MpegEncContext *s = avctx->priv_data;
128 
130  return 0;
131 }
132 
136 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
137  int pos= (get_bits_count(&s->gb)+7)>>3;
138 
139  if(s->divx_packed || s->avctx->hwaccel){
140  //we would have to scan through the whole buf to handle the weird reordering ...
141  return buf_size;
142  }else if(s->flags&CODEC_FLAG_TRUNCATED){
143  pos -= s->parse_context.last_index;
144  if(pos<0) pos=0; // padding is not really read so this might be -1
145  return pos;
146  }else{
147  if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
148  if(pos+10>buf_size) pos=buf_size; // oops ;)
149 
150  return pos;
151  }
152 }
153 
155  const int part_mask= s->partitioned_frame ? (ER_AC_END|ER_AC_ERROR) : 0x7F;
156  const int mb_size = 16;
157  s->last_resync_gb= s->gb;
158  s->first_slice_line= 1;
159 
160  s->resync_mb_x= s->mb_x;
161  s->resync_mb_y= s->mb_y;
162 
163  ff_set_qscale(s, s->qscale);
164 
165  if (s->avctx->hwaccel) {
166  const uint8_t *start= s->gb.buffer + get_bits_count(&s->gb)/8;
167  const uint8_t *end = ff_h263_find_resync_marker(start + 1, s->gb.buffer_end);
168  skip_bits_long(&s->gb, 8*(end - start));
169  return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start);
170  }
171 
172  if(s->partitioned_frame){
173  const int qscale= s->qscale;
174 
176  if(ff_mpeg4_decode_partitions(s) < 0)
177  return -1;
178  }
179 
180  /* restore variables which were modified */
181  s->first_slice_line=1;
182  s->mb_x= s->resync_mb_x;
183  s->mb_y= s->resync_mb_y;
184  ff_set_qscale(s, qscale);
185  }
186 
187  for(; s->mb_y < s->mb_height; s->mb_y++) {
188  /* per-row end of slice checks */
189  if(s->msmpeg4_version){
190  if(s->resync_mb_y + s->slice_height == s->mb_y){
192 
193  return 0;
194  }
195  }
196 
197  if(s->msmpeg4_version==1){
198  s->last_dc[0]=
199  s->last_dc[1]=
200  s->last_dc[2]= 128;
201  }
202 
204  for(; s->mb_x < s->mb_width; s->mb_x++) {
205  int ret;
206 
208 
209  if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
210  s->first_slice_line=0;
211  }
212 
213  /* DCT & quantize */
214 
215  s->mv_dir = MV_DIR_FORWARD;
216  s->mv_type = MV_TYPE_16X16;
217 // s->mb_skipped = 0;
218  av_dlog(s, "%d %d %06X\n",
219  ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
220  ret= s->decode_mb(s, s->block);
221 
224 
225  if(ret<0){
226  const int xy= s->mb_x + s->mb_y*s->mb_stride;
227  if(ret==SLICE_END){
228  ff_MPV_decode_mb(s, s->block);
229  if(s->loop_filter)
231 
232  ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
233 
234  s->padding_bug_score--;
235 
236  if(++s->mb_x >= s->mb_width){
237  s->mb_x=0;
238  ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
240  s->mb_y++;
241  }
242  return 0;
243  }else if(ret==SLICE_NOEND){
244  av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
245  ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, ER_MB_END&part_mask);
246  return -1;
247  }
248  av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
249  ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR&part_mask);
250 
251  return -1;
252  }
253 
254  ff_MPV_decode_mb(s, s->block);
255  if(s->loop_filter)
257  }
258 
259  ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
261 
262  s->mb_x= 0;
263  }
264 
265  assert(s->mb_x==0 && s->mb_y==s->mb_height);
266 
269  && get_bits_left(&s->gb) >= 48
270  && show_bits(&s->gb, 24)==0x4010
271  && !s->data_partitioning)
272  s->padding_bug_score+=32;
273 
274  /* try to detect the padding bug */
277  && get_bits_left(&s->gb) >=0
278  && get_bits_left(&s->gb) < 48
279 // && !s->resync_marker
280  && !s->data_partitioning){
281 
282  const int bits_count= get_bits_count(&s->gb);
283  const int bits_left = s->gb.size_in_bits - bits_count;
284 
285  if(bits_left==0){
286  s->padding_bug_score+=16;
287  } else if(bits_left != 1){
288  int v= show_bits(&s->gb, 8);
289  v|= 0x7F >> (7-(bits_count&7));
290 
291  if(v==0x7F && bits_left<=8)
292  s->padding_bug_score--;
293  else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
294  s->padding_bug_score+= 4;
295  else
296  s->padding_bug_score++;
297  }
298  }
299 
301  if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version>=0 || !s->resync_marker)*/)
303  else
305  }
306 
307  // handle formats which don't have unique end markers
308  if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
309  int left= get_bits_left(&s->gb);
310  int max_extra=7;
311 
312  /* no markers in M$ crap */
314  max_extra+= 17;
315 
316  /* buggy padding but the frame should still end approximately at the bitstream end */
318  max_extra+= 48;
319  else if((s->workaround_bugs&FF_BUG_NO_PADDING))
320  max_extra+= 256*256*256*64;
321 
322  if(left>max_extra){
323  av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
324  }
325  else if(left<0){
326  av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
327  }else
329 
330  return 0;
331  }
332 
333  av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
334  get_bits_left(&s->gb),
335  show_bits(&s->gb, 24), s->padding_bug_score);
336 
337  ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
338 
339  return -1;
340 }
341 
343  void *data, int *got_frame,
344  AVPacket *avpkt)
345 {
346  const uint8_t *buf = avpkt->data;
347  int buf_size = avpkt->size;
348  MpegEncContext *s = avctx->priv_data;
349  int ret;
350  AVFrame *pict = data;
351 
352 #ifdef PRINT_FRAME_TIME
353 uint64_t time= rdtsc();
354 #endif
355  s->flags= avctx->flags;
356  s->flags2= avctx->flags2;
357 
358  /* no supplementary picture */
359  if (buf_size == 0) {
360  /* special case for last picture */
361  if (s->low_delay==0 && s->next_picture_ptr) {
362  *pict = s->next_picture_ptr->f;
364 
365  *got_frame = 1;
366  }
367 
368  return 0;
369  }
370 
372  int next;
373 
375  next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
377  next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
378  }else{
379  av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
380  return -1;
381  }
382 
383  if( ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
384  return buf_size;
385  }
386 
387 
388  if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
390  }else
391  init_get_bits(&s->gb, buf, buf_size*8);
393 
394  if (!s->context_initialized) {
395  if (ff_MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
396  return -1;
397  }
398 
399  /* We need to set current_picture_ptr before reading the header,
400  * otherwise we cannot store anyting in there */
401  if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
402  int i= ff_find_unused_picture(s, 0);
403  if (i < 0)
404  return i;
405  s->current_picture_ptr= &s->picture[i];
406  }
407 
408  /* let's go :-) */
409  if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5) {
411  } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
413  } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
414  if(s->avctx->extradata_size && s->picture_number==0){
415  GetBitContext gb;
416 
418  ret = ff_mpeg4_decode_picture_header(s, &gb);
419  }
420  ret = ff_mpeg4_decode_picture_header(s, &s->gb);
421  } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
423  } else if (CONFIG_FLV_DECODER && s->h263_flv) {
425  } else {
427  }
428 
429  if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
430 
431  /* skip if the header was thrashed */
432  if (ret < 0){
433  av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
434  return -1;
435  }
436 
437  avctx->has_b_frames= !s->low_delay;
438 
439  if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
440  if(s->stream_codec_tag == AV_RL32("XVID") ||
441  s->codec_tag == AV_RL32("XVID") || s->codec_tag == AV_RL32("XVIX") ||
442  s->codec_tag == AV_RL32("RMP4") ||
443  s->codec_tag == AV_RL32("SIPP")
444  )
445  s->xvid_build= 0;
446 #if 0
447  if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
448  && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
449  s->xvid_build= 0;
450 #endif
451  }
452 
453  if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
454  if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
455  s->divx_version= 400; //divx 4
456  }
457 
458  if(s->xvid_build>=0 && s->divx_version>=0){
459  s->divx_version=
460  s->divx_build= -1;
461  }
462 
464  if(s->codec_tag == AV_RL32("XVIX"))
466 
467  if(s->codec_tag == AV_RL32("UMP4")){
469  }
470 
471  if(s->divx_version>=500 && s->divx_build<1814){
473  }
474 
475  if(s->divx_version>502 && s->divx_build<1814){
477  }
478 
479  if(s->xvid_build<=3U)
480  s->padding_bug_score= 256*256*256*64;
481 
482  if(s->xvid_build<=1U)
484 
485  if(s->xvid_build<=12U)
487 
488  if(s->xvid_build<=32U)
490 
491 #define SET_QPEL_FUNC(postfix1, postfix2) \
492  s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
493  s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
494  s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
495 
496  if(s->lavc_build<4653U)
498 
499  if(s->lavc_build<4655U)
501 
502  if(s->lavc_build<4670U){
504  }
505 
506  if(s->lavc_build<=4712U)
508 
509  if(s->divx_version>=0)
511  if(s->divx_version==501 && s->divx_build==20020416)
512  s->padding_bug_score= 256*256*256*64;
513 
514  if(s->divx_version<500U){
516  }
517 
518  if(s->divx_version>=0)
520 #if 0
521  if(s->divx_version==500)
522  s->padding_bug_score= 256*256*256*64;
523 
524  /* very ugly XVID padding bug detection FIXME/XXX solve this differently
525  * Let us hope this at least works.
526  */
527  if( s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==-1
528  && s->codec_id==AV_CODEC_ID_MPEG4 && s->vo_type==0)
530 
531  if(s->lavc_build<4609U) //FIXME not sure about the version num but a 4609 file seems ok
533 #endif
534  }
535 
537  SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
538  SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
539  SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
540  SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
541  SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
542  SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
543 
544  SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
545  SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
546  SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
547  SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
548  SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
549  SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
550  }
551 
552  if(avctx->debug & FF_DEBUG_BUGS)
553  av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
555  s->divx_packed ? "p" : "");
556 
557 #if HAVE_MMX
559  avctx->idct_algo= FF_IDCT_XVIDMMX;
561  s->picture_number=0;
562  }
563 #endif
564 
565  /* After H263 & mpeg4 header decode we have the height, width,*/
566  /* and other parameters. So then we could init the picture */
567  /* FIXME: By the way H263 decoder is evolving it should have */
568  /* an H263EncContext */
569 
570  if (s->width != avctx->coded_width ||
571  s->height != avctx->coded_height ||
572  s->context_reinit) {
573  /* H.263 could change picture size any time */
574  s->context_reinit = 0;
575 
576  avcodec_set_dimensions(avctx, s->width, s->height);
577 
578  if ((ret = ff_MPV_common_frame_size_change(s)))
579  return ret;
580  }
581 
584 
585  // for skipping the frame
588 
589  /* skip B-frames if we don't have reference frames */
590  if (s->last_picture_ptr == NULL &&
591  (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))
592  return get_consumed_bytes(s, buf_size);
595  || avctx->skip_frame >= AVDISCARD_ALL)
596  return get_consumed_bytes(s, buf_size);
597 
598  if(s->next_p_frame_damaged){
600  return get_consumed_bytes(s, buf_size);
601  else
603  }
604 
608  }else if((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
611  }else{
614  }
615 
616  if(ff_MPV_frame_start(s, avctx) < 0)
617  return -1;
618 
619  if (!s->divx_packed) ff_thread_finish_setup(avctx);
620 
623  goto frame_end;
624  }
625 
626  if (avctx->hwaccel) {
627  if (avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer) < 0)
628  return -1;
629  }
630 
632 
633  //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
634  //which is not available before ff_MPV_frame_start()
635  if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5){
637  if(ret<0) return ret;
638  if(ret==1) goto intrax8_decoded;
639  }
640 
641  /* decode each macroblock */
642  s->mb_x=0;
643  s->mb_y=0;
644 
645  ret = decode_slice(s);
646  while(s->mb_y<s->mb_height){
647  if(s->msmpeg4_version){
648  if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_left(&s->gb)<0)
649  break;
650  }else{
651  int prev_x=s->mb_x, prev_y=s->mb_y;
652  if(ff_h263_resync(s)<0)
653  break;
654  if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
655  s->error_occurred = 1;
656  }
657 
658  if(s->msmpeg4_version<4 && s->h263_pred)
660 
661  if (decode_slice(s) < 0) ret = AVERROR_INVALIDDATA;
662  }
663 
665  if(!CONFIG_MSMPEG4_DECODER || ff_msmpeg4_decode_ext_header(s, buf_size) < 0){
667  }
668 
669  assert(s->bitstream_buffer_size==0);
670 frame_end:
671  /* divx 5.01+ bistream reorder stuff */
672  if(s->codec_id==AV_CODEC_ID_MPEG4 && s->divx_packed){
673  int current_pos= get_bits_count(&s->gb)>>3;
674  int startcode_found=0;
675 
676  if(buf_size - current_pos > 5){
677  int i;
678  for(i=current_pos; i<buf_size-3; i++){
679  if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
680  startcode_found=1;
681  break;
682  }
683  }
684  }
685  if(s->gb.buffer == s->bitstream_buffer && buf_size>7 && s->xvid_build>=0){ //xvid style
686  startcode_found=1;
687  current_pos=0;
688  }
689 
690  if(startcode_found){
692  &s->bitstream_buffer,
694  buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
695  if (!s->bitstream_buffer)
696  return AVERROR(ENOMEM);
697  memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
698  s->bitstream_buffer_size= buf_size - current_pos;
699  }
700  }
701 
702 intrax8_decoded:
703  ff_er_frame_end(s);
704 
705  if (avctx->hwaccel) {
706  if (avctx->hwaccel->end_frame(avctx) < 0)
707  return -1;
708  }
709 
710  ff_MPV_frame_end(s);
711 
713  assert(s->current_picture.f.pict_type == s->pict_type);
714  if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
715  *pict = s->current_picture_ptr->f;
716  } else if (s->last_picture_ptr != NULL) {
717  *pict = s->last_picture_ptr->f;
718  }
719 
720  if(s->last_picture_ptr || s->low_delay){
721  *got_frame = 1;
722  ff_print_debug_info(s, pict);
723  }
724 
725 #ifdef PRINT_FRAME_TIME
726 av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
727 #endif
728 
729  return (ret && (avctx->err_recognition & AV_EF_EXPLODE))?ret:get_consumed_bytes(s, buf_size);
730 }
731 
733  .name = "h263",
734  .type = AVMEDIA_TYPE_VIDEO,
735  .id = AV_CODEC_ID_H263,
736  .priv_data_size = sizeof(MpegEncContext),
740  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
742  .flush = ff_mpeg_flush,
743  .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
744  .pix_fmts = ff_hwaccel_pixfmt_list_420,
745 };