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  if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 5.01+/xvid frame reorder
388  ret = init_get_bits8(&s->gb, s->bitstream_buffer,
390  else
391  ret = init_get_bits8(&s->gb, buf, buf_size);
392  s->bitstream_buffer_size = 0;
393 
394  if (ret < 0)
395  return ret;
396 
397  if (!s->context_initialized)
398  // we need the idct permutaton for reading a custom matrix
399  if ((ret = ff_MPV_common_init(s)) < 0)
400  return ret;
401 
402  /* We need to set current_picture_ptr before reading the header,
403  * otherwise we cannot store anyting in there */
404  if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
405  int i= ff_find_unused_picture(s, 0);
406  if (i < 0)
407  return i;
408  s->current_picture_ptr= &s->picture[i];
409  }
410 
411  /* let's go :-) */
412  if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5) {
414  } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
416  } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
417  if(s->avctx->extradata_size && s->picture_number==0){
418  GetBitContext gb;
419 
420  ret = init_get_bits8(&gb, s->avctx->extradata,
421  s->avctx->extradata_size);
422  if (ret < 0)
423  return ret;
425  }
426  ret = ff_mpeg4_decode_picture_header(s, &s->gb);
427  } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
429  } else if (CONFIG_FLV_DECODER && s->h263_flv) {
431  } else {
433  }
434 
435  if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
436 
437  /* skip if the header was thrashed */
438  if (ret < 0){
439  av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
440  return -1;
441  }
442 
443  avctx->has_b_frames= !s->low_delay;
444 
445  if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
446  if(s->stream_codec_tag == AV_RL32("XVID") ||
447  s->codec_tag == AV_RL32("XVID") || s->codec_tag == AV_RL32("XVIX") ||
448  s->codec_tag == AV_RL32("RMP4") ||
449  s->codec_tag == AV_RL32("SIPP")
450  )
451  s->xvid_build= 0;
452 #if 0
453  if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
454  && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
455  s->xvid_build= 0;
456 #endif
457  }
458 
459  if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
460  if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
461  s->divx_version= 400; //divx 4
462  }
463 
464  if(s->xvid_build>=0 && s->divx_version>=0){
465  s->divx_version=
466  s->divx_build= -1;
467  }
468 
470  if(s->codec_tag == AV_RL32("XVIX"))
472 
473  if(s->codec_tag == AV_RL32("UMP4")){
475  }
476 
477  if(s->divx_version>=500 && s->divx_build<1814){
479  }
480 
481  if(s->divx_version>502 && s->divx_build<1814){
483  }
484 
485  if(s->xvid_build<=3U)
486  s->padding_bug_score= 256*256*256*64;
487 
488  if(s->xvid_build<=1U)
490 
491  if(s->xvid_build<=12U)
493 
494  if(s->xvid_build<=32U)
496 
497 #define SET_QPEL_FUNC(postfix1, postfix2) \
498  s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
499  s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
500  s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
501 
502  if(s->lavc_build<4653U)
504 
505  if(s->lavc_build<4655U)
507 
508  if(s->lavc_build<4670U){
510  }
511 
512  if(s->lavc_build<=4712U)
514 
515  if(s->divx_version>=0)
517  if(s->divx_version==501 && s->divx_build==20020416)
518  s->padding_bug_score= 256*256*256*64;
519 
520  if(s->divx_version<500U){
522  }
523 
524  if(s->divx_version>=0)
526 #if 0
527  if(s->divx_version==500)
528  s->padding_bug_score= 256*256*256*64;
529 
530  /* very ugly XVID padding bug detection FIXME/XXX solve this differently
531  * Let us hope this at least works.
532  */
533  if( s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==-1
534  && s->codec_id==AV_CODEC_ID_MPEG4 && s->vo_type==0)
536 
537  if(s->lavc_build<4609U) //FIXME not sure about the version num but a 4609 file seems ok
539 #endif
540  }
541 
543  SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
544  SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
545  SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
546  SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
547  SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
548  SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
549 
550  SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
551  SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
552  SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
553  SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
554  SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
555  SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
556  }
557 
558  if(avctx->debug & FF_DEBUG_BUGS)
559  av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
561  s->divx_packed ? "p" : "");
562 
563 #if HAVE_MMX
565  avctx->idct_algo= FF_IDCT_XVIDMMX;
567  s->picture_number=0;
568  }
569 #endif
570 
571  /* After H263 & mpeg4 header decode we have the height, width,*/
572  /* and other parameters. So then we could init the picture */
573  /* FIXME: By the way H263 decoder is evolving it should have */
574  /* an H263EncContext */
575 
576  if (s->width != avctx->coded_width ||
577  s->height != avctx->coded_height ||
578  s->context_reinit) {
579  /* H.263 could change picture size any time */
580  s->context_reinit = 0;
581 
582  avcodec_set_dimensions(avctx, s->width, s->height);
583 
584  if ((ret = ff_MPV_common_frame_size_change(s)))
585  return ret;
586  }
587 
590 
591  // for skipping the frame
594 
595  /* skip B-frames if we don't have reference frames */
596  if (s->last_picture_ptr == NULL &&
597  (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))
598  return get_consumed_bytes(s, buf_size);
601  || avctx->skip_frame >= AVDISCARD_ALL)
602  return get_consumed_bytes(s, buf_size);
603 
604  if(s->next_p_frame_damaged){
606  return get_consumed_bytes(s, buf_size);
607  else
609  }
610 
614  }else if((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
617  }else{
620  }
621 
622  if(ff_MPV_frame_start(s, avctx) < 0)
623  return -1;
624 
625  if (!s->divx_packed) ff_thread_finish_setup(avctx);
626 
629  goto frame_end;
630  }
631 
632  if (avctx->hwaccel) {
633  if (avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer) < 0)
634  return -1;
635  }
636 
638 
639  //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
640  //which is not available before ff_MPV_frame_start()
641  if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5){
643  if(ret<0) return ret;
644  if(ret==1) goto intrax8_decoded;
645  }
646 
647  /* decode each macroblock */
648  s->mb_x=0;
649  s->mb_y=0;
650 
651  ret = decode_slice(s);
652  while(s->mb_y<s->mb_height){
653  if(s->msmpeg4_version){
654  if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_left(&s->gb)<0)
655  break;
656  }else{
657  int prev_x=s->mb_x, prev_y=s->mb_y;
658  if(ff_h263_resync(s)<0)
659  break;
660  if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
661  s->error_occurred = 1;
662  }
663 
664  if(s->msmpeg4_version<4 && s->h263_pred)
666 
667  if (decode_slice(s) < 0) ret = AVERROR_INVALIDDATA;
668  }
669 
671  if(!CONFIG_MSMPEG4_DECODER || ff_msmpeg4_decode_ext_header(s, buf_size) < 0){
673  }
674 
675  assert(s->bitstream_buffer_size==0);
676 frame_end:
677  /* divx 5.01+ bistream reorder stuff */
678  if(s->codec_id==AV_CODEC_ID_MPEG4 && s->divx_packed){
679  int current_pos= get_bits_count(&s->gb)>>3;
680  int startcode_found=0;
681 
682  if(buf_size - current_pos > 5){
683  int i;
684  for(i=current_pos; i<buf_size-3; i++){
685  if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
686  startcode_found=1;
687  break;
688  }
689  }
690  }
691  if(s->gb.buffer == s->bitstream_buffer && buf_size>7 && s->xvid_build>=0){ //xvid style
692  startcode_found=1;
693  current_pos=0;
694  }
695 
696  if(startcode_found){
698  &s->bitstream_buffer,
700  buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
701  if (!s->bitstream_buffer)
702  return AVERROR(ENOMEM);
703  memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
704  s->bitstream_buffer_size= buf_size - current_pos;
705  }
706  }
707 
708 intrax8_decoded:
709  ff_er_frame_end(s);
710 
711  if (avctx->hwaccel) {
712  if (avctx->hwaccel->end_frame(avctx) < 0)
713  return -1;
714  }
715 
716  ff_MPV_frame_end(s);
717 
719  assert(s->current_picture.f.pict_type == s->pict_type);
720  if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
721  *pict = s->current_picture_ptr->f;
722  } else if (s->last_picture_ptr != NULL) {
723  *pict = s->last_picture_ptr->f;
724  }
725 
726  if(s->last_picture_ptr || s->low_delay){
727  *got_frame = 1;
728  ff_print_debug_info(s, pict);
729  }
730 
731 #ifdef PRINT_FRAME_TIME
732 av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
733 #endif
734 
735  return (ret && (avctx->err_recognition & AV_EF_EXPLODE))?ret:get_consumed_bytes(s, buf_size);
736 }
737 
739  .name = "h263",
740  .type = AVMEDIA_TYPE_VIDEO,
741  .id = AV_CODEC_ID_H263,
742  .priv_data_size = sizeof(MpegEncContext),
746  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
748  .flush = ff_mpeg_flush,
749  .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
750  .pix_fmts = ff_hwaccel_pixfmt_list_420,
751 };