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ituh263dec.c
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1 /*
2  * ITU H.263 bitstream decoder
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * H.263+ support.
5  * Copyright (c) 2001 Juan J. Sierralta P
6  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 /**
26  * @file
27  * H.263 decoder.
28  */
29 
30 #define UNCHECKED_BITSTREAM_READER 1
31 #include <limits.h>
32 
33 #include "libavutil/attributes.h"
34 #include "libavutil/imgutils.h"
35 #include "libavutil/internal.h"
36 #include "libavutil/mathematics.h"
37 #include "avcodec.h"
38 #include "mpegvideo.h"
39 #include "h263.h"
40 #include "h263data.h"
41 #include "internal.h"
42 #include "mathops.h"
43 #include "mpegutils.h"
44 #include "unary.h"
45 #include "flv.h"
46 #include "rv10.h"
47 #include "mpeg4video.h"
48 #include "mpegvideodata.h"
49 
50 // The defines below define the number of bits that are read at once for
51 // reading vlc values. Changing these may improve speed and data cache needs
52 // be aware though that decreasing them may need the number of stages that is
53 // passed to get_vlc* to be increased.
54 #define MV_VLC_BITS 9
55 #define H263_MBTYPE_B_VLC_BITS 6
56 #define CBPC_B_VLC_BITS 3
57 
58 static const int h263_mb_type_b_map[15]= {
71  0, //stuffing
74 };
75 
78  av_log(s->avctx, AV_LOG_DEBUG, "qp:%d %c size:%d rnd:%d%s%s%s%s%s%s%s%s%s %d/%d\n",
80  s->gb.size_in_bits, 1-s->no_rounding,
81  s->obmc ? " AP" : "",
82  s->umvplus ? " UMV" : "",
83  s->h263_long_vectors ? " LONG" : "",
84  s->h263_plus ? " +" : "",
85  s->h263_aic ? " AIC" : "",
86  s->alt_inter_vlc ? " AIV" : "",
87  s->modified_quant ? " MQ" : "",
88  s->loop_filter ? " LOOP" : "",
89  s->h263_slice_structured ? " SS" : "",
91  );
92  }
93 }
94 
95 /***********************************************/
96 /* decoding */
97 
101 static VLC mv_vlc;
104 
105 /* init vlcs */
106 
107 /* XXX: find a better solution to handle static init */
109 {
110  static volatile int done = 0;
111 
112  if (!done) {
113  INIT_VLC_STATIC(&ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9,
115  ff_h263_intra_MCBPC_code, 1, 1, 72);
116  INIT_VLC_STATIC(&ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28,
118  ff_h263_inter_MCBPC_code, 1, 1, 198);
119  INIT_VLC_STATIC(&ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16,
120  &ff_h263_cbpy_tab[0][1], 2, 1,
121  &ff_h263_cbpy_tab[0][0], 2, 1, 64);
122  INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 33,
123  &ff_mvtab[0][1], 2, 1,
124  &ff_mvtab[0][0], 2, 1, 538);
129  INIT_VLC_STATIC(&h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15,
130  &ff_h263_mbtype_b_tab[0][1], 2, 1,
131  &ff_h263_mbtype_b_tab[0][0], 2, 1, 80);
132  INIT_VLC_STATIC(&cbpc_b_vlc, CBPC_B_VLC_BITS, 4,
133  &ff_cbpc_b_tab[0][1], 2, 1,
134  &ff_cbpc_b_tab[0][0], 2, 1, 8);
135  done = 1;
136  }
137 }
138 
140 {
141  int i, mb_pos;
142 
143  for (i = 0; i < 6; i++)
144  if (s->mb_num - 1 <= ff_mba_max[i])
145  break;
146  mb_pos = get_bits(&s->gb, ff_mba_length[i]);
147  s->mb_x = mb_pos % s->mb_width;
148  s->mb_y = mb_pos / s->mb_width;
149 
150  return mb_pos;
151 }
152 
153 /**
154  * Decode the group of blocks header or slice header.
155  * @return <0 if an error occurred
156  */
158 {
159  unsigned int val, gob_number;
160  int left;
161 
162  /* Check for GOB Start Code */
163  val = show_bits(&s->gb, 16);
164  if(val)
165  return -1;
166 
167  /* We have a GBSC probably with GSTUFF */
168  skip_bits(&s->gb, 16); /* Drop the zeros */
169  left= get_bits_left(&s->gb);
170  //MN: we must check the bits left or we might end in an infinite loop (or segfault)
171  for(;left>13; left--){
172  if(get_bits1(&s->gb)) break; /* Seek the '1' bit */
173  }
174  if(left<=13)
175  return -1;
176 
177  if(s->h263_slice_structured){
178  if(check_marker(s->avctx, &s->gb, "before MBA")==0)
179  return -1;
180 
182 
183  if(s->mb_num > 1583)
184  if(check_marker(s->avctx, &s->gb, "after MBA")==0)
185  return -1;
186 
187  s->qscale = get_bits(&s->gb, 5); /* SQUANT */
188  if(check_marker(s->avctx, &s->gb, "after SQUANT")==0)
189  return -1;
190  skip_bits(&s->gb, 2); /* GFID */
191  }else{
192  gob_number = get_bits(&s->gb, 5); /* GN */
193  s->mb_x= 0;
194  s->mb_y= s->gob_index* gob_number;
195  skip_bits(&s->gb, 2); /* GFID */
196  s->qscale = get_bits(&s->gb, 5); /* GQUANT */
197  }
198 
199  if(s->mb_y >= s->mb_height)
200  return -1;
201 
202  if(s->qscale==0)
203  return -1;
204 
205  return 0;
206 }
207 
208 /**
209  * Decode the group of blocks / video packet header.
210  * @return bit position of the resync_marker, or <0 if none was found
211  */
213  int left, pos, ret;
214 
215  if(s->codec_id==AV_CODEC_ID_MPEG4){
216  skip_bits1(&s->gb);
217  align_get_bits(&s->gb);
218  }
219 
220  if(show_bits(&s->gb, 16)==0){
221  pos= get_bits_count(&s->gb);
222  if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4)
224  else
225  ret= h263_decode_gob_header(s);
226  if(ret>=0)
227  return pos;
228  }
229  //OK, it's not where it is supposed to be ...
230  s->gb= s->last_resync_gb;
231  align_get_bits(&s->gb);
232  left= get_bits_left(&s->gb);
233 
234  for(;left>16+1+5+5; left-=8){
235  if(show_bits(&s->gb, 16)==0){
236  GetBitContext bak= s->gb;
237 
238  pos= get_bits_count(&s->gb);
239  if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4)
241  else
242  ret= h263_decode_gob_header(s);
243  if(ret>=0)
244  return pos;
245 
246  s->gb= bak;
247  }
248  skip_bits(&s->gb, 8);
249  }
250 
251  return -1;
252 }
253 
255 {
256  int code, val, sign, shift;
257  code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
258 
259  if (code == 0)
260  return pred;
261  if (code < 0)
262  return 0xffff;
263 
264  sign = get_bits1(&s->gb);
265  shift = f_code - 1;
266  val = code;
267  if (shift) {
268  val = (val - 1) << shift;
269  val |= get_bits(&s->gb, shift);
270  val++;
271  }
272  if (sign)
273  val = -val;
274  val += pred;
275 
276  /* modulo decoding */
277  if (!s->h263_long_vectors) {
278  val = sign_extend(val, 5 + f_code);
279  } else {
280  /* horrible H.263 long vector mode */
281  if (pred < -31 && val < -63)
282  val += 64;
283  if (pred > 32 && val > 63)
284  val -= 64;
285 
286  }
287  return val;
288 }
289 
290 
291 /* Decode RVLC of H.263+ UMV */
293 {
294  int code = 0, sign;
295 
296  if (get_bits1(&s->gb)) /* Motion difference = 0 */
297  return pred;
298 
299  code = 2 + get_bits1(&s->gb);
300 
301  while (get_bits1(&s->gb))
302  {
303  code <<= 1;
304  code += get_bits1(&s->gb);
305  }
306  sign = code & 1;
307  code >>= 1;
308 
309  code = (sign) ? (pred - code) : (pred + code);
310  ff_tlog(s->avctx,"H.263+ UMV Motion = %d\n", code);
311  return code;
312 
313 }
314 
315 /**
316  * read the next MVs for OBMC. yes this is an ugly hack, feel free to send a patch :)
317  */
319  GetBitContext gb= s->gb;
320 
321  int cbpc, i, pred_x, pred_y, mx, my;
322  int16_t *mot_val;
323  const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
324  const int stride= s->b8_stride*2;
325 
326  for(i=0; i<4; i++)
327  s->block_index[i]+= 2;
328  for(i=4; i<6; i++)
329  s->block_index[i]+= 1;
330  s->mb_x++;
331 
333 
334  do{
335  if (get_bits1(&s->gb)) {
336  /* skip mb */
337  mot_val = s->current_picture.motion_val[0][s->block_index[0]];
338  mot_val[0 ]= mot_val[2 ]=
339  mot_val[0+stride]= mot_val[2+stride]= 0;
340  mot_val[1 ]= mot_val[3 ]=
341  mot_val[1+stride]= mot_val[3+stride]= 0;
342 
344  goto end;
345  }
346  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
347  }while(cbpc == 20);
348 
349  if(cbpc & 4){
351  }else{
352  get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
353  if (cbpc & 8) {
354  if(s->modified_quant){
355  if(get_bits1(&s->gb)) skip_bits(&s->gb, 1);
356  else skip_bits(&s->gb, 5);
357  }else
358  skip_bits(&s->gb, 2);
359  }
360 
361  if ((cbpc & 16) == 0) {
363  /* 16x16 motion prediction */
364  mot_val= ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
365  if (s->umvplus)
366  mx = h263p_decode_umotion(s, pred_x);
367  else
368  mx = ff_h263_decode_motion(s, pred_x, 1);
369 
370  if (s->umvplus)
371  my = h263p_decode_umotion(s, pred_y);
372  else
373  my = ff_h263_decode_motion(s, pred_y, 1);
374 
375  mot_val[0 ]= mot_val[2 ]=
376  mot_val[0+stride]= mot_val[2+stride]= mx;
377  mot_val[1 ]= mot_val[3 ]=
378  mot_val[1+stride]= mot_val[3+stride]= my;
379  } else {
381  for(i=0;i<4;i++) {
382  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
383  if (s->umvplus)
384  mx = h263p_decode_umotion(s, pred_x);
385  else
386  mx = ff_h263_decode_motion(s, pred_x, 1);
387 
388  if (s->umvplus)
389  my = h263p_decode_umotion(s, pred_y);
390  else
391  my = ff_h263_decode_motion(s, pred_y, 1);
392  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
393  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
394  mot_val[0] = mx;
395  mot_val[1] = my;
396  }
397  }
398  }
399 end:
400 
401  for(i=0; i<4; i++)
402  s->block_index[i]-= 2;
403  for(i=4; i<6; i++)
404  s->block_index[i]-= 1;
405  s->mb_x--;
406 
407  s->gb= gb;
408 }
409 
411  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
412 
413  if(s->modified_quant){
414  if(get_bits1(&s->gb))
416  else
417  s->qscale= get_bits(&s->gb, 5);
418  }else
419  s->qscale += quant_tab[get_bits(&s->gb, 2)];
420  ff_set_qscale(s, s->qscale);
421 }
422 
423 static int h263_decode_block(MpegEncContext * s, int16_t * block,
424  int n, int coded)
425 {
426  int level, i, j, run;
427  RLTable *rl = &ff_h263_rl_inter;
428  const uint8_t *scan_table;
429  GetBitContext gb= s->gb;
430 
431  scan_table = s->intra_scantable.permutated;
432  if (s->h263_aic && s->mb_intra) {
433  rl = &ff_rl_intra_aic;
434  i = 0;
435  if (s->ac_pred) {
436  if (s->h263_aic_dir)
437  scan_table = s->intra_v_scantable.permutated; /* left */
438  else
439  scan_table = s->intra_h_scantable.permutated; /* top */
440  }
441  } else if (s->mb_intra) {
442  /* DC coef */
443  if (CONFIG_RV10_DECODER && s->codec_id == AV_CODEC_ID_RV10) {
444  if (s->rv10_version == 3 && s->pict_type == AV_PICTURE_TYPE_I) {
445  int component, diff;
446  component = (n <= 3 ? 0 : n - 4 + 1);
447  level = s->last_dc[component];
448  if (s->rv10_first_dc_coded[component]) {
449  diff = ff_rv_decode_dc(s, n);
450  if (diff == 0xffff)
451  return -1;
452  level += diff;
453  level = level & 0xff; /* handle wrap round */
454  s->last_dc[component] = level;
455  } else {
456  s->rv10_first_dc_coded[component] = 1;
457  }
458  } else {
459  level = get_bits(&s->gb, 8);
460  if (level == 255)
461  level = 128;
462  }
463  }else{
464  level = get_bits(&s->gb, 8);
465  if((level&0x7F) == 0){
466  av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y);
468  return -1;
469  }
470  if (level == 255)
471  level = 128;
472  }
473  block[0] = level;
474  i = 1;
475  } else {
476  i = 0;
477  }
478  if (!coded) {
479  if (s->mb_intra && s->h263_aic)
480  goto not_coded;
481  s->block_last_index[n] = i - 1;
482  return 0;
483  }
484 retry:
485  {
486  OPEN_READER(re, &s->gb);
487  i--; // offset by -1 to allow direct indexing of scan_table
488  for(;;) {
489  UPDATE_CACHE(re, &s->gb);
490  GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
491  if (run == 66) {
492  if (level){
493  CLOSE_READER(re, &s->gb);
494  av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
495  return -1;
496  }
497  /* escape */
498  if (CONFIG_FLV_DECODER && s->h263_flv > 1) {
499  int is11 = SHOW_UBITS(re, &s->gb, 1);
500  SKIP_CACHE(re, &s->gb, 1);
501  run = SHOW_UBITS(re, &s->gb, 7) + 1;
502  if (is11) {
503  SKIP_COUNTER(re, &s->gb, 1 + 7);
504  UPDATE_CACHE(re, &s->gb);
505  level = SHOW_SBITS(re, &s->gb, 11);
506  SKIP_COUNTER(re, &s->gb, 11);
507  } else {
508  SKIP_CACHE(re, &s->gb, 7);
509  level = SHOW_SBITS(re, &s->gb, 7);
510  SKIP_COUNTER(re, &s->gb, 1 + 7 + 7);
511  }
512  } else {
513  run = SHOW_UBITS(re, &s->gb, 7) + 1;
514  SKIP_CACHE(re, &s->gb, 7);
515  level = (int8_t)SHOW_UBITS(re, &s->gb, 8);
516  SKIP_COUNTER(re, &s->gb, 7 + 8);
517  if(level == -128){
518  UPDATE_CACHE(re, &s->gb);
519  if (s->codec_id == AV_CODEC_ID_RV10) {
520  /* XXX: should patch encoder too */
521  level = SHOW_SBITS(re, &s->gb, 12);
522  SKIP_COUNTER(re, &s->gb, 12);
523  }else{
524  level = SHOW_UBITS(re, &s->gb, 5);
525  SKIP_CACHE(re, &s->gb, 5);
526  level |= SHOW_SBITS(re, &s->gb, 6)<<5;
527  SKIP_COUNTER(re, &s->gb, 5 + 6);
528  }
529  }
530  }
531  } else {
532  if (SHOW_UBITS(re, &s->gb, 1))
533  level = -level;
534  SKIP_COUNTER(re, &s->gb, 1);
535  }
536  i += run;
537  if (i >= 64){
538  CLOSE_READER(re, &s->gb);
539  // redo update without last flag, revert -1 offset
540  i = i - run + ((run-1)&63) + 1;
541  if (i < 64) {
542  // only last marker, no overrun
543  block[scan_table[i]] = level;
544  break;
545  }
546  if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){
547  //Looks like a hack but no, it's the way it is supposed to work ...
548  rl = &ff_rl_intra_aic;
549  i = 0;
550  s->gb= gb;
551  s->bdsp.clear_block(block);
552  goto retry;
553  }
554  av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n", s->mb_x, s->mb_y, s->mb_intra);
555  return -1;
556  }
557  j = scan_table[i];
558  block[j] = level;
559  }
560  }
561 not_coded:
562  if (s->mb_intra && s->h263_aic) {
563  ff_h263_pred_acdc(s, block, n);
564  i = 63;
565  }
566  s->block_last_index[n] = i;
567  return 0;
568 }
569 
570 static int h263_skip_b_part(MpegEncContext *s, int cbp)
571 {
572  LOCAL_ALIGNED_16(int16_t, dblock, [64]);
573  int i, mbi;
574  int bli[6];
575 
576  /* we have to set s->mb_intra to zero to decode B-part of PB-frame correctly
577  * but real value should be restored in order to be used later (in OBMC condition)
578  */
579  mbi = s->mb_intra;
580  memcpy(bli, s->block_last_index, sizeof(bli));
581  s->mb_intra = 0;
582  for (i = 0; i < 6; i++) {
583  if (h263_decode_block(s, dblock, i, cbp&32) < 0)
584  return -1;
585  cbp+=cbp;
586  }
587  s->mb_intra = mbi;
588  memcpy(s->block_last_index, bli, sizeof(bli));
589  return 0;
590 }
591 
592 static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
593 {
594  int c, mv = 1;
595 
596  if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame
597  c = get_bits1(gb);
598  if (pb_frame == 2 && c)
599  mv = !get_bits1(gb);
600  } else { // h.263 Annex M improved PB-frame
601  mv = get_unary(gb, 0, 4) + 1;
602  c = mv & 1;
603  mv = !!(mv & 2);
604  }
605  if(c)
606  *cbpb = get_bits(gb, 6);
607  return mv;
608 }
609 
611  int16_t block[6][64])
612 {
613  int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
614  int16_t *mot_val;
615  const int xy= s->mb_x + s->mb_y * s->mb_stride;
616  int cbpb = 0, pb_mv_count = 0;
617 
618  av_assert2(!s->h263_pred);
619 
620  if (s->pict_type == AV_PICTURE_TYPE_P) {
621  do{
622  if (get_bits1(&s->gb)) {
623  /* skip mb */
624  s->mb_intra = 0;
625  for(i=0;i<6;i++)
626  s->block_last_index[i] = -1;
627  s->mv_dir = MV_DIR_FORWARD;
628  s->mv_type = MV_TYPE_16X16;
630  s->mv[0][0][0] = 0;
631  s->mv[0][0][1] = 0;
632  s->mb_skipped = !(s->obmc | s->loop_filter);
633  goto end;
634  }
635  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
636  if (cbpc < 0){
637  av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
638  return -1;
639  }
640  }while(cbpc == 20);
641 
642  s->bdsp.clear_blocks(s->block[0]);
643 
644  dquant = cbpc & 8;
645  s->mb_intra = ((cbpc & 4) != 0);
646  if (s->mb_intra) goto intra;
647 
648  if(s->pb_frame && get_bits1(&s->gb))
649  pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
650  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
651 
652  if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
653  cbpy ^= 0xF;
654 
655  cbp = (cbpc & 3) | (cbpy << 2);
656  if (dquant) {
658  }
659 
660  s->mv_dir = MV_DIR_FORWARD;
661  if ((cbpc & 16) == 0) {
663  /* 16x16 motion prediction */
664  s->mv_type = MV_TYPE_16X16;
665  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
666  if (s->umvplus)
667  mx = h263p_decode_umotion(s, pred_x);
668  else
669  mx = ff_h263_decode_motion(s, pred_x, 1);
670 
671  if (mx >= 0xffff)
672  return -1;
673 
674  if (s->umvplus)
675  my = h263p_decode_umotion(s, pred_y);
676  else
677  my = ff_h263_decode_motion(s, pred_y, 1);
678 
679  if (my >= 0xffff)
680  return -1;
681  s->mv[0][0][0] = mx;
682  s->mv[0][0][1] = my;
683 
684  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
685  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
686  } else {
688  s->mv_type = MV_TYPE_8X8;
689  for(i=0;i<4;i++) {
690  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
691  if (s->umvplus)
692  mx = h263p_decode_umotion(s, pred_x);
693  else
694  mx = ff_h263_decode_motion(s, pred_x, 1);
695  if (mx >= 0xffff)
696  return -1;
697 
698  if (s->umvplus)
699  my = h263p_decode_umotion(s, pred_y);
700  else
701  my = ff_h263_decode_motion(s, pred_y, 1);
702  if (my >= 0xffff)
703  return -1;
704  s->mv[0][i][0] = mx;
705  s->mv[0][i][1] = my;
706  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
707  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
708  mot_val[0] = mx;
709  mot_val[1] = my;
710  }
711  }
712  } else if(s->pict_type==AV_PICTURE_TYPE_B) {
713  int mb_type;
714  const int stride= s->b8_stride;
715  int16_t *mot_val0 = s->current_picture.motion_val[0][2 * (s->mb_x + s->mb_y * stride)];
716  int16_t *mot_val1 = s->current_picture.motion_val[1][2 * (s->mb_x + s->mb_y * stride)];
717 // const int mv_xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
718 
719  //FIXME ugly
720  mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]=
721  mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]=
722  mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]=
723  mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0;
724 
725  do{
726  mb_type= get_vlc2(&s->gb, h263_mbtype_b_vlc.table, H263_MBTYPE_B_VLC_BITS, 2);
727  if (mb_type < 0){
728  av_log(s->avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n", s->mb_x, s->mb_y);
729  return -1;
730  }
731 
732  mb_type= h263_mb_type_b_map[ mb_type ];
733  }while(!mb_type);
734 
735  s->mb_intra = IS_INTRA(mb_type);
736  if(HAS_CBP(mb_type)){
737  s->bdsp.clear_blocks(s->block[0]);
738  cbpc = get_vlc2(&s->gb, cbpc_b_vlc.table, CBPC_B_VLC_BITS, 1);
739  if(s->mb_intra){
740  dquant = IS_QUANT(mb_type);
741  goto intra;
742  }
743 
744  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
745 
746  if (cbpy < 0){
747  av_log(s->avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
748  return -1;
749  }
750 
751  if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
752  cbpy ^= 0xF;
753 
754  cbp = (cbpc & 3) | (cbpy << 2);
755  }else
756  cbp=0;
757 
758  av_assert2(!s->mb_intra);
759 
760  if(IS_QUANT(mb_type)){
762  }
763 
764  if(IS_DIRECT(mb_type)){
766  mb_type |= ff_mpeg4_set_direct_mv(s, 0, 0);
767  }else{
768  s->mv_dir = 0;
770 //FIXME UMV
771 
772  if(USES_LIST(mb_type, 0)){
773  int16_t *mot_val= ff_h263_pred_motion(s, 0, 0, &mx, &my);
774  s->mv_dir = MV_DIR_FORWARD;
775 
776  mx = ff_h263_decode_motion(s, mx, 1);
777  my = ff_h263_decode_motion(s, my, 1);
778 
779  s->mv[0][0][0] = mx;
780  s->mv[0][0][1] = my;
781  mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
782  mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
783  }
784 
785  if(USES_LIST(mb_type, 1)){
786  int16_t *mot_val= ff_h263_pred_motion(s, 0, 1, &mx, &my);
787  s->mv_dir |= MV_DIR_BACKWARD;
788 
789  mx = ff_h263_decode_motion(s, mx, 1);
790  my = ff_h263_decode_motion(s, my, 1);
791 
792  s->mv[1][0][0] = mx;
793  s->mv[1][0][1] = my;
794  mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
795  mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
796  }
797  }
798 
799  s->current_picture.mb_type[xy] = mb_type;
800  } else { /* I-Frame */
801  do{
802  cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
803  if (cbpc < 0){
804  av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
805  return -1;
806  }
807  }while(cbpc == 8);
808 
809  s->bdsp.clear_blocks(s->block[0]);
810 
811  dquant = cbpc & 4;
812  s->mb_intra = 1;
813 intra:
815  if (s->h263_aic) {
816  s->ac_pred = get_bits1(&s->gb);
817  if(s->ac_pred){
819 
820  s->h263_aic_dir = get_bits1(&s->gb);
821  }
822  }else
823  s->ac_pred = 0;
824 
825  if(s->pb_frame && get_bits1(&s->gb))
826  pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
827  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
828  if(cbpy<0){
829  av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
830  return -1;
831  }
832  cbp = (cbpc & 3) | (cbpy << 2);
833  if (dquant) {
835  }
836 
837  pb_mv_count += !!s->pb_frame;
838  }
839 
840  while(pb_mv_count--){
841  ff_h263_decode_motion(s, 0, 1);
842  ff_h263_decode_motion(s, 0, 1);
843  }
844 
845  /* decode each block */
846  for (i = 0; i < 6; i++) {
847  if (h263_decode_block(s, block[i], i, cbp&32) < 0)
848  return -1;
849  cbp+=cbp;
850  }
851 
852  if(s->pb_frame && h263_skip_b_part(s, cbpb) < 0)
853  return -1;
854  if(s->obmc && !s->mb_intra){
855  if(s->pict_type == AV_PICTURE_TYPE_P && s->mb_x+1<s->mb_width && s->mb_num_left != 1)
856  preview_obmc(s);
857  }
858 end:
859 
860  /* per-MB end of slice check */
861  {
862  int v= show_bits(&s->gb, 16);
863 
864  if (get_bits_left(&s->gb) < 16) {
865  v >>= 16 - get_bits_left(&s->gb);
866  }
867 
868  if(v==0)
869  return SLICE_END;
870  }
871 
872  return SLICE_OK;
873 }
874 
875 /* Most is hardcoded; should extend to handle all H.263 streams. */
877 {
878  int format, width, height, i, ret;
879  uint32_t startcode;
880 
881  align_get_bits(&s->gb);
882 
883  if (show_bits(&s->gb, 2) == 2 && s->avctx->frame_number == 0) {
884  av_log(s->avctx, AV_LOG_WARNING, "Header looks like RTP instead of H.263\n");
885  }
886 
887  startcode= get_bits(&s->gb, 22-8);
888 
889  for(i= get_bits_left(&s->gb); i>24; i-=8) {
890  startcode = ((startcode << 8) | get_bits(&s->gb, 8)) & 0x003FFFFF;
891 
892  if(startcode == 0x20)
893  break;
894  }
895 
896  if (startcode != 0x20) {
897  av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
898  return -1;
899  }
900  /* temporal reference */
901  i = get_bits(&s->gb, 8); /* picture timestamp */
902  if( (s->picture_number&~0xFF)+i < s->picture_number)
903  i+= 256;
904  s->picture_number= (s->picture_number&~0xFF) + i;
905 
906  /* PTYPE starts here */
907  if (check_marker(s->avctx, &s->gb, "in PTYPE") != 1) {
908  return -1;
909  }
910  if (get_bits1(&s->gb) != 0) {
911  av_log(s->avctx, AV_LOG_ERROR, "Bad H.263 id\n");
912  return -1; /* H.263 id */
913  }
914  skip_bits1(&s->gb); /* split screen off */
915  skip_bits1(&s->gb); /* camera off */
916  skip_bits1(&s->gb); /* freeze picture release off */
917 
918  format = get_bits(&s->gb, 3);
919  /*
920  0 forbidden
921  1 sub-QCIF
922  10 QCIF
923  7 extended PTYPE (PLUSPTYPE)
924  */
925 
926  if (format != 7 && format != 6) {
927  s->h263_plus = 0;
928  /* H.263v1 */
929  width = ff_h263_format[format][0];
930  height = ff_h263_format[format][1];
931  if (!width)
932  return -1;
933 
935 
936  s->h263_long_vectors = get_bits1(&s->gb);
937 
938  if (get_bits1(&s->gb) != 0) {
939  av_log(s->avctx, AV_LOG_ERROR, "H.263 SAC not supported\n");
940  return -1; /* SAC: off */
941  }
942  s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
943  s->unrestricted_mv = s->h263_long_vectors || s->obmc;
944 
945  s->pb_frame = get_bits1(&s->gb);
946  s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
947  skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */
948 
949  s->width = width;
950  s->height = height;
951  s->avctx->sample_aspect_ratio= (AVRational){12,11};
952  s->avctx->framerate = (AVRational){ 30000, 1001 };
953  } else {
954  int ufep;
955 
956  /* H.263v2 */
957  s->h263_plus = 1;
958  ufep = get_bits(&s->gb, 3); /* Update Full Extended PTYPE */
959 
960  /* ufep other than 0 and 1 are reserved */
961  if (ufep == 1) {
962  /* OPPTYPE */
963  format = get_bits(&s->gb, 3);
964  ff_dlog(s->avctx, "ufep=1, format: %d\n", format);
965  s->custom_pcf= get_bits1(&s->gb);
966  s->umvplus = get_bits1(&s->gb); /* Unrestricted Motion Vector */
967  if (get_bits1(&s->gb) != 0) {
968  av_log(s->avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n");
969  }
970  s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
971  s->h263_aic = get_bits1(&s->gb); /* Advanced Intra Coding (AIC) */
972  s->loop_filter= get_bits1(&s->gb);
973  s->unrestricted_mv = s->umvplus || s->obmc || s->loop_filter;
974  if(s->avctx->lowres)
975  s->loop_filter = 0;
976 
978  if (get_bits1(&s->gb) != 0) {
979  av_log(s->avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n");
980  }
981  if (get_bits1(&s->gb) != 0) {
982  av_log(s->avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n");
983  }
984  s->alt_inter_vlc= get_bits1(&s->gb);
985  s->modified_quant= get_bits1(&s->gb);
986  if(s->modified_quant)
988 
989  skip_bits(&s->gb, 1); /* Prevent start code emulation */
990 
991  skip_bits(&s->gb, 3); /* Reserved */
992  } else if (ufep != 0) {
993  av_log(s->avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep);
994  return -1;
995  }
996 
997  /* MPPTYPE */
998  s->pict_type = get_bits(&s->gb, 3);
999  switch(s->pict_type){
1000  case 0: s->pict_type= AV_PICTURE_TYPE_I;break;
1001  case 1: s->pict_type= AV_PICTURE_TYPE_P;break;
1002  case 2: s->pict_type= AV_PICTURE_TYPE_P;s->pb_frame = 3;break;
1003  case 3: s->pict_type= AV_PICTURE_TYPE_B;break;
1004  case 7: s->pict_type= AV_PICTURE_TYPE_I;break; //ZYGO
1005  default:
1006  return -1;
1007  }
1008  skip_bits(&s->gb, 2);
1009  s->no_rounding = get_bits1(&s->gb);
1010  skip_bits(&s->gb, 4);
1011 
1012  /* Get the picture dimensions */
1013  if (ufep) {
1014  if (format == 6) {
1015  /* Custom Picture Format (CPFMT) */
1016  s->aspect_ratio_info = get_bits(&s->gb, 4);
1017  ff_dlog(s->avctx, "aspect: %d\n", s->aspect_ratio_info);
1018  /* aspect ratios:
1019  0 - forbidden
1020  1 - 1:1
1021  2 - 12:11 (CIF 4:3)
1022  3 - 10:11 (525-type 4:3)
1023  4 - 16:11 (CIF 16:9)
1024  5 - 40:33 (525-type 16:9)
1025  6-14 - reserved
1026  */
1027  width = (get_bits(&s->gb, 9) + 1) * 4;
1028  check_marker(s->avctx, &s->gb, "in dimensions");
1029  height = get_bits(&s->gb, 9) * 4;
1030  ff_dlog(s->avctx, "\nH.263+ Custom picture: %dx%d\n",width,height);
1032  /* expected dimensions */
1033  s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8);
1034  s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8);
1035  }else{
1037  }
1038  } else {
1039  width = ff_h263_format[format][0];
1040  height = ff_h263_format[format][1];
1041  s->avctx->sample_aspect_ratio= (AVRational){12,11};
1042  }
1044  if ((width == 0) || (height == 0))
1045  return -1;
1046  s->width = width;
1047  s->height = height;
1048 
1049  if(s->custom_pcf){
1050  int gcd;
1051  s->avctx->framerate.num = 1800000;
1052  s->avctx->framerate.den = 1000 + get_bits1(&s->gb);
1053  s->avctx->framerate.den *= get_bits(&s->gb, 7);
1054  if(s->avctx->framerate.den == 0){
1055  av_log(s, AV_LOG_ERROR, "zero framerate\n");
1056  return -1;
1057  }
1058  gcd= av_gcd(s->avctx->framerate.den, s->avctx->framerate.num);
1059  s->avctx->framerate.den /= gcd;
1060  s->avctx->framerate.num /= gcd;
1061  }else{
1062  s->avctx->framerate = (AVRational){ 30000, 1001 };
1063  }
1064  }
1065 
1066  if(s->custom_pcf){
1067  skip_bits(&s->gb, 2); //extended Temporal reference
1068  }
1069 
1070  if (ufep) {
1071  if (s->umvplus) {
1072  if(get_bits1(&s->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */
1073  skip_bits1(&s->gb);
1074  }
1075  if(s->h263_slice_structured){
1076  if (get_bits1(&s->gb) != 0) {
1077  av_log(s->avctx, AV_LOG_ERROR, "rectangular slices not supported\n");
1078  }
1079  if (get_bits1(&s->gb) != 0) {
1080  av_log(s->avctx, AV_LOG_ERROR, "unordered slices not supported\n");
1081  }
1082  }
1083  }
1084 
1085  s->qscale = get_bits(&s->gb, 5);
1086  }
1087 
1088  if ((ret = av_image_check_size(s->width, s->height, 0, s)) < 0)
1089  return ret;
1090 
1091  s->mb_width = (s->width + 15) / 16;
1092  s->mb_height = (s->height + 15) / 16;
1093  s->mb_num = s->mb_width * s->mb_height;
1094 
1095  if (s->pb_frame) {
1096  skip_bits(&s->gb, 3); /* Temporal reference for B-pictures */
1097  if (s->custom_pcf)
1098  skip_bits(&s->gb, 2); //extended Temporal reference
1099  skip_bits(&s->gb, 2); /* Quantization information for B-pictures */
1100  }
1101 
1102  if (s->pict_type!=AV_PICTURE_TYPE_B) {
1103  s->time = s->picture_number;
1104  s->pp_time = s->time - s->last_non_b_time;
1105  s->last_non_b_time = s->time;
1106  }else{
1107  s->time = s->picture_number;
1108  s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
1109  if (s->pp_time <=s->pb_time ||
1110  s->pp_time <= s->pp_time - s->pb_time ||
1111  s->pp_time <= 0){
1112  s->pp_time = 2;
1113  s->pb_time = 1;
1114  }
1116  }
1117 
1118  /* PEI */
1119  if (skip_1stop_8data_bits(&s->gb) < 0)
1120  return AVERROR_INVALIDDATA;
1121 
1122  if(s->h263_slice_structured){
1123  if (check_marker(s->avctx, &s->gb, "SEPB1") != 1) {
1124  return -1;
1125  }
1126 
1127  ff_h263_decode_mba(s);
1128 
1129  if (check_marker(s->avctx, &s->gb, "SEPB2") != 1) {
1130  return -1;
1131  }
1132  }
1133  s->f_code = 1;
1134 
1135  if(s->h263_aic){
1136  s->y_dc_scale_table=
1138  }else{
1139  s->y_dc_scale_table=
1141  }
1142 
1144  if (s->pict_type == AV_PICTURE_TYPE_I && s->codec_tag == AV_RL32("ZYGO") && get_bits_left(&s->gb) >= 85 + 13*3*16 + 50){
1145  int i,j;
1146  for(i=0; i<85; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1147  av_log(s->avctx, AV_LOG_DEBUG, "\n");
1148  for(i=0; i<13; i++){
1149  for(j=0; j<3; j++){
1150  int v= get_bits(&s->gb, 8);
1151  v |= get_sbits(&s->gb, 8)<<8;
1152  av_log(s->avctx, AV_LOG_DEBUG, " %5d", v);
1153  }
1154  av_log(s->avctx, AV_LOG_DEBUG, "\n");
1155  }
1156  for(i=0; i<50; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1157  }
1158 
1159  return 0;
1160 }
av_cold void ff_h263_decode_init_vlc(void)
Definition: ituh263dec.c:108
int rv10_first_dc_coded[3]
Definition: mpegvideo.h:419
#define ff_tlog(ctx,...)
Definition: internal.h:65
AVRational framerate
Definition: avcodec.h:3358
#define MB_TYPE_SKIP
Definition: avcodec.h:1253
const char const char void * val
Definition: avisynth_c.h:771
int aspect_ratio_info
Definition: mpegvideo.h:400
int picture_number
Definition: mpegvideo.h:124
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
ScanTable intra_v_scantable
Definition: mpegvideo.h:90
static int h263_decode_gob_header(MpegEncContext *s)
Decode the group of blocks header or slice header.
Definition: ituh263dec.c:157
static int shift(int a, int b)
Definition: sonic.c:82
VLC ff_h263_inter_MCBPC_vlc
Definition: ituh263dec.c:99
#define CBPY_VLC_BITS
Definition: h263.h:41
const uint8_t * y_dc_scale_table
qscale -> y_dc_scale table
Definition: mpegvideo.h:185
const uint16_t ff_mba_max[6]
Definition: h263data.c:267
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:35
float re
Definition: fft.c:82
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:247
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define INIT_VLC_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size)
Definition: vlc.h:57
#define SKIP_COUNTER(name, gb, num)
Definition: get_bits.h:167
static int check_marker(void *logctx, GetBitContext *s, const char *msg)
Definition: get_bits.h:388
RLTable ff_rl_intra_aic
Definition: h263data.c:230
int num
Numerator.
Definition: rational.h:59
#define MB_TYPE_INTRA4x4
Definition: avcodec.h:1242
enum AVCodecID codec_id
Definition: mpegvideo.h:109
#define AV_EF_COMPLIANT
consider all spec non compliances as errors
Definition: avcodec.h:2962
void(* clear_blocks)(int16_t *blocks)
Definition: blockdsp.h:36
int obmc
overlapped block motion compensation
Definition: mpegvideo.h:366
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel...
Definition: avcodec.h:2070
#define MB_TYPE_INTRA
Definition: mpegutils.h:75
static int h263_decode_block(MpegEncContext *s, int16_t *block, int n, int coded)
Definition: ituh263dec.c:423
#define MB_TYPE_QUANT
Definition: avcodec.h:1261
#define AV_EF_BITSTREAM
detect bitstream specification deviations
Definition: avcodec.h:2956
mpegvideo header.
#define HAS_CBP(a)
Definition: mpegutils.h:103
const uint16_t ff_h263_format[8][2]
Definition: h263data.c:238
#define FF_ASPECT_EXTENDED
Definition: avcodec.h:1864
uint8_t permutated[64]
Definition: idctdsp.h:31
uint8_t run
Definition: svq3.c:205
#define SLICE_OK
Definition: mpegvideo.h:500
int mb_num
number of MBs of a picture
Definition: mpegvideo.h:130
RLTable.
Definition: rl.h:39
int qscale
QP.
Definition: mpegvideo.h:201
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:232
int h263_aic
Advanced INTRA Coding (AIC)
Definition: mpegvideo.h:84
int16_t * ff_h263_pred_motion(MpegEncContext *s, int block, int dir, int *px, int *py)
Definition: h263.c:309
Macro definitions for various function/variable attributes.
int modified_quant
Definition: mpegvideo.h:379
static int16_t block[64]
Definition: dct.c:113
#define USES_LIST(a, list)
Definition: mpegutils.h:101
int alt_inter_vlc
alternative inter vlc
Definition: mpegvideo.h:378
int mb_num_left
number of MBs left in this video packet (for partitioned Slices only)
Definition: mpegvideo.h:359
int64_t time
time of current frame
Definition: mpegvideo.h:388
const uint8_t ff_mpeg1_dc_scale_table[128]
Definition: mpegvideodata.c:34
#define MV_DIRECT
bidirectional mode where the difference equals the MV of the last P/S/I-Frame (MPEG-4) ...
Definition: mpegvideo.h:264
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:63
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2900
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
static VLC h263_mbtype_b_vlc
Definition: ituh263dec.c:102
int ff_rv_decode_dc(MpegEncContext *s, int n)
Definition: rv10.c:198
int no_rounding
apply no rounding to motion compensation (MPEG-4, msmpeg4, ...) for B-frames rounding mode is always ...
Definition: mpegvideo.h:284
H.263 tables.
Picture current_picture
copy of the current picture structure.
Definition: mpegvideo.h:177
GetBitContext last_resync_gb
used to search for the next resync marker
Definition: mpegvideo.h:358
#define height
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:199
char av_get_picture_type_char(enum AVPictureType pict_type)
Return a single letter to describe the given picture type pict_type.
Definition: utils.c:91
#define ff_dlog(a,...)
const uint8_t ff_h263_intra_MCBPC_bits[9]
Definition: h263data.c:35
uint16_t pp_time
time distance between the last 2 p,s,i frames
Definition: mpegvideo.h:390
const uint8_t ff_mba_length[7]
Definition: h263data.c:271
int mb_height
number of MBs horizontally & vertically
Definition: mpegvideo.h:126
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:3070
static int h263_skip_b_part(MpegEncContext *s, int cbp)
Definition: ituh263dec.c:570
int codec_tag
internal codec_tag upper case converted from avctx codec_tag
Definition: mpegvideo.h:117
#define av_log(a,...)
void ff_set_qscale(MpegEncContext *s, int qscale)
set qscale and update qscale dependent variables.
Definition: mpegvideo.c:2802
const uint8_t ff_h263_mbtype_b_tab[15][2]
Definition: h263data.c:59
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:568
#define H263_MBTYPE_B_VLC_BITS
Definition: ituh263dec.c:55
int h263_plus
H.263+ headers.
Definition: mpegvideo.h:106
uint8_t ff_h263_static_rl_table_store[2][2][2 *MAX_RUN+MAX_LEVEL+3]
Definition: h263data.c:31
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:160
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int last_dc[3]
last DC values for MPEG-1
Definition: mpegvideo.h:182
const uint8_t ff_h263_inter_MCBPC_code[28]
Definition: h263data.c:40
int mb_skipped
MUST BE SET only during DECODING.
Definition: mpegvideo.h:192
const uint8_t ff_modified_quant_tab[2][32]
Definition: h263data.c:252
int unrestricted_mv
mv can point outside of the coded picture
Definition: mpegvideo.h:220
int ff_h263_decode_motion(MpegEncContext *s, int pred, int f_code)
Definition: ituh263dec.c:254
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
static const int h263_mb_type_b_map[15]
Definition: ituh263dec.c:58
int h263_slice_structured
Definition: mpegvideo.h:377
#define INTER_MCBPC_VLC_BITS
Definition: h263.h:40
int64_t av_gcd(int64_t a, int64_t b)
Compute the greatest common divisor of two integer operands.
Definition: mathematics.c:37
void ff_mpeg4_init_direct_mv(MpegEncContext *s)
Definition: mpeg4video.c:71
int ff_mpeg4_decode_video_packet_header(Mpeg4DecContext *ctx)
Decode the next video packet.
static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
Definition: ituh263dec.c:592
GetBitContext gb
Definition: mpegvideo.h:445
#define CLOSE_READER(name, gb)
Definition: get_bits.h:131
#define INIT_VLC_RL(rl, static_size)
Definition: rl.h:63
#define GET_RL_VLC(level, run, name, gb, table, bits,max_depth, need_update)
Definition: get_bits.h:490
Definition: vlc.h:26
common internal API header
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:251
const uint8_t ff_h263_inter_MCBPC_bits[28]
Definition: h263data.c:49
const uint8_t ff_h263_chroma_qscale_table[32]
Definition: h263data.c:262
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2947
#define MB_TYPE_DIRECT2
Definition: avcodec.h:1250
#define IS_DIRECT(a)
Definition: mpegutils.h:86
int umvplus
== H.263+ && unrestricted_mv
Definition: mpegvideo.h:375
#define width
int16_t(*[2] motion_val)[2]
Definition: mpegpicture.h:53
int size_in_bits
Definition: get_bits.h:58
static unsigned int show_bits(GetBitContext *s, int n)
Show 1-25 bits.
Definition: get_bits.h:282
#define MB_TYPE_L0L1
Definition: avcodec.h:1260
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE(*table)[2], int bits, int max_depth)
Parse a vlc code.
Definition: get_bits.h:535
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:83
int n
Definition: avisynth_c.h:684
int pb_frame
PB-frame mode (0 = none, 1 = base, 2 = improved)
Definition: mpegvideo.h:103
#define MB_TYPE_ACPRED
Definition: avcodec.h:1251
VLC ff_h263_cbpy_vlc
Definition: ituh263dec.c:100
#define MB_TYPE_L1
Definition: avcodec.h:1259
int ff_h263_decode_mba(MpegEncContext *s)
Definition: ituh263dec.c:139
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:48
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:193
static int h263p_decode_umotion(MpegEncContext *s, int pred)
Definition: ituh263dec.c:292
int block_index[6]
index to current MB in block based arrays with edges
Definition: mpegvideo.h:293
static const float pred[4]
Definition: siprdata.h:259
static const int8_t mv[256][2]
Definition: 4xm.c:77
#define MV_TYPE_16X16
1 vector for the whole mb
Definition: mpegvideo.h:266
#define MV_VLC_BITS
Definition: ituh263dec.c:54
const uint8_t ff_aic_dc_scale_table[32]
Definition: h263data.c:247
#define MV_DIR_BACKWARD
Definition: mpegvideo.h:263
int64_t last_non_b_time
Definition: mpegvideo.h:389
Libavcodec external API header.
int h263_flv
use flv H.263 header
Definition: mpegvideo.h:107
BlockDSPContext bdsp
Definition: mpegvideo.h:223
int debug
debug
Definition: avcodec.h:2899
const uint8_t ff_h263_intra_MCBPC_code[9]
Definition: h263data.c:34
ScanTable intra_scantable
Definition: mpegvideo.h:88
int height
picture size. must be a multiple of 16
Definition: mpegvideo.h:97
#define IS_QUANT(a)
Definition: mpegutils.h:97
#define OPEN_READER(name, gb)
Definition: get_bits.h:120
av_cold int ff_rl_init(RLTable *rl, uint8_t static_store[2][2 *MAX_RUN+MAX_LEVEL+3])
Definition: rl.c:39
#define SLICE_END
end marker found
Definition: mpegvideo.h:502
VLC ff_h263_intra_MCBPC_vlc
Definition: ituh263dec.c:98
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:299
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:324
static const char * format
Definition: movenc.c:47
ScanTable intra_h_scantable
Definition: mpegvideo.h:89
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:292
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define CBPC_B_VLC_BITS
Definition: ituh263dec.c:56
#define MB_TYPE_16x16
Definition: avcodec.h:1245
RLTable ff_h263_rl_inter
Definition: h263data.c:161
static VLC mv_vlc
Definition: ituh263dec.c:101
int ff_h263_resync(MpegEncContext *s)
Decode the group of blocks / video packet header.
Definition: ituh263dec.c:212
#define SKIP_CACHE(name, gb, num)
Definition: get_bits.h:162
const uint8_t ff_cbpc_b_tab[4][2]
Definition: h263data.c:77
int f_code
forward MV resolution
Definition: mpegvideo.h:235
int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my)
Definition: mpeg4video.c:117
const uint8_t ff_h263_cbpy_tab[16][2]
Definition: h263data.c:84
int ff_h263_decode_picture_header(MpegEncContext *s)
Definition: ituh263dec.c:876
#define MV_DIR_FORWARD
Definition: mpegvideo.h:262
int pict_type
AV_PICTURE_TYPE_I, AV_PICTURE_TYPE_P, AV_PICTURE_TYPE_B, ...
Definition: mpegvideo.h:209
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:139
static void h263_decode_dquant(MpegEncContext *s)
Definition: ituh263dec.c:410
int h263_pred
use MPEG-4/H.263 ac/dc predictions
Definition: mpegvideo.h:102
const AVRational ff_h263_pixel_aspect[16]
Definition: h263data.c:275
const uint8_t * c_dc_scale_table
qscale -> c_dc_scale table
Definition: mpegvideo.h:186
uint8_t level
Definition: svq3.c:206
int mv[2][4][2]
motion vectors for a macroblock first coordinate : 0 = forward 1 = backward second " : depend...
Definition: mpegvideo.h:276
int b8_stride
2*mb_width+1 used for some 8x8 block arrays to allow simple addressing
Definition: mpegvideo.h:128
MpegEncContext.
Definition: mpegvideo.h:78
struct AVCodecContext * avctx
Definition: mpegvideo.h:95
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:194
#define MB_TYPE_CBP
Definition: avcodec.h:1262
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
common internal api header.
int mb_stride
mb_width+1 used for some arrays to allow simple addressing of left & top MBs without sig11 ...
Definition: mpegvideo.h:127
void ff_h263_pred_acdc(MpegEncContext *s, int16_t *block, int n)
Definition: h263.c:222
#define TEX_VLC_BITS
Definition: dv.h:93
static int get_unary(GetBitContext *gb, int stop, int len)
Get unary code of limited length.
Definition: unary.h:33
static double c[64]
#define MB_TYPE_8x8
Definition: avcodec.h:1248
Bi-dir predicted.
Definition: avutil.h:270
int den
Denominator.
Definition: rational.h:60
const uint8_t * chroma_qscale_table
qscale -> chroma_qscale (H.263)
Definition: mpegvideo.h:187
#define IS_INTRA(x, y)
void * priv_data
Definition: avcodec.h:1701
static av_always_inline int diff(const uint32_t a, const uint32_t b)
static VLC cbpc_b_vlc
Definition: ituh263dec.c:103
void ff_h263_show_pict_info(MpegEncContext *s)
Print picture info if FF_DEBUG_PICT_INFO is set.
Definition: ituh263dec.c:76
int16_t(* block)[64]
points to one of the following blocks
Definition: mpegvideo.h:497
VLC_TYPE(* table)[2]
code, bits
Definition: vlc.h:28
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:445
int chroma_qscale
chroma QP
Definition: mpegvideo.h:202
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2452
static void preview_obmc(MpegEncContext *s)
read the next MVs for OBMC.
Definition: ituh263dec.c:318
uint32_t * mb_type
types and macros are defined in mpegutils.h
Definition: mpegpicture.h:56
#define LOCAL_ALIGNED_16(t, v,...)
Definition: internal.h:121
int rv10_version
RV10 version: 0 or 3.
Definition: mpegvideo.h:418
static int skip_1stop_8data_bits(GetBitContext *gb)
Definition: get_bits.h:573
int h263_long_vectors
use horrible H.263v1 long vector mode
Definition: mpegvideo.h:221
#define stride
#define MV_TYPE_8X8
4 vectors (H.263, MPEG-4 4MV)
Definition: mpegvideo.h:267
int h263_aic_dir
AIC direction: 0 = left, 1 = top.
Definition: mpegvideo.h:376
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
int ff_h263_decode_mb(MpegEncContext *s, int16_t block[6][64])
Definition: ituh263dec.c:610
#define MB_TYPE_L0
Definition: avcodec.h:1258
Predicted.
Definition: avutil.h:269
#define INTRA_MCBPC_VLC_BITS
Definition: h263.h:39
uint16_t pb_time
time distance between the last b and p,s,i frame
Definition: mpegvideo.h:391
const uint8_t ff_mvtab[33][2]
Definition: h263data.c:90