FFmpeg  4.0
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  left = FFMIN(left, 32);
171  //MN: we must check the bits left or we might end in an infinite loop (or segfault)
172  for(;left>13; left--){
173  if(get_bits1(&s->gb)) break; /* Seek the '1' bit */
174  }
175  if(left<=13)
176  return -1;
177 
178  if(s->h263_slice_structured){
179  if(check_marker(s->avctx, &s->gb, "before MBA")==0)
180  return -1;
181 
183 
184  if(s->mb_num > 1583)
185  if(check_marker(s->avctx, &s->gb, "after MBA")==0)
186  return -1;
187 
188  s->qscale = get_bits(&s->gb, 5); /* SQUANT */
189  if(check_marker(s->avctx, &s->gb, "after SQUANT")==0)
190  return -1;
191  skip_bits(&s->gb, 2); /* GFID */
192  }else{
193  gob_number = get_bits(&s->gb, 5); /* GN */
194  s->mb_x= 0;
195  s->mb_y= s->gob_index* gob_number;
196  skip_bits(&s->gb, 2); /* GFID */
197  s->qscale = get_bits(&s->gb, 5); /* GQUANT */
198  }
199 
200  if(s->mb_y >= s->mb_height)
201  return -1;
202 
203  if(s->qscale==0)
204  return -1;
205 
206  return 0;
207 }
208 
209 /**
210  * Decode the group of blocks / video packet header / slice header (MPEG-4 Studio).
211  * @return bit position of the resync_marker, or <0 if none was found
212  */
214  int left, pos, ret;
215 
216  /* In MPEG-4 studio mode look for a new slice startcode
217  * and decode slice header */
219  align_get_bits(&s->gb);
220 
221  while (get_bits_left(&s->gb) >= 32 && show_bits_long(&s->gb, 32) != SLICE_START_CODE) {
222  get_bits(&s->gb, 8);
223  }
224 
225  if (show_bits_long(&s->gb, 32) == SLICE_START_CODE)
226  return get_bits_count(&s->gb);
227  else
228  return -1;
229  }
230 
231  if(s->codec_id==AV_CODEC_ID_MPEG4){
232  skip_bits1(&s->gb);
233  align_get_bits(&s->gb);
234  }
235 
236  if(show_bits(&s->gb, 16)==0){
237  pos= get_bits_count(&s->gb);
240  else
241  ret= h263_decode_gob_header(s);
242  if(ret>=0)
243  return pos;
244  }
245  //OK, it's not where it is supposed to be ...
246  s->gb= s->last_resync_gb;
247  align_get_bits(&s->gb);
248  left= get_bits_left(&s->gb);
249 
250  for(;left>16+1+5+5; left-=8){
251  if(show_bits(&s->gb, 16)==0){
252  GetBitContext bak= s->gb;
253 
254  pos= get_bits_count(&s->gb);
257  else
258  ret= h263_decode_gob_header(s);
259  if(ret>=0)
260  return pos;
261 
262  s->gb= bak;
263  }
264  skip_bits(&s->gb, 8);
265  }
266 
267  return -1;
268 }
269 
271 {
272  int code, val, sign, shift;
273  code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
274 
275  if (code == 0)
276  return pred;
277  if (code < 0)
278  return 0xffff;
279 
280  sign = get_bits1(&s->gb);
281  shift = f_code - 1;
282  val = code;
283  if (shift) {
284  val = (val - 1) << shift;
285  val |= get_bits(&s->gb, shift);
286  val++;
287  }
288  if (sign)
289  val = -val;
290  val += pred;
291 
292  /* modulo decoding */
293  if (!s->h263_long_vectors) {
294  val = sign_extend(val, 5 + f_code);
295  } else {
296  /* horrible H.263 long vector mode */
297  if (pred < -31 && val < -63)
298  val += 64;
299  if (pred > 32 && val > 63)
300  val -= 64;
301 
302  }
303  return val;
304 }
305 
306 
307 /* Decode RVLC of H.263+ UMV */
309 {
310  int code = 0, sign;
311 
312  if (get_bits1(&s->gb)) /* Motion difference = 0 */
313  return pred;
314 
315  code = 2 + get_bits1(&s->gb);
316 
317  while (get_bits1(&s->gb))
318  {
319  code <<= 1;
320  code += get_bits1(&s->gb);
321  if (code >= 32768) {
322  avpriv_request_sample(s->avctx, "Huge DMV");
323  return 0xffff;
324  }
325  }
326  sign = code & 1;
327  code >>= 1;
328 
329  code = (sign) ? (pred - code) : (pred + code);
330  ff_tlog(s->avctx,"H.263+ UMV Motion = %d\n", code);
331  return code;
332 
333 }
334 
335 /**
336  * read the next MVs for OBMC. yes this is an ugly hack, feel free to send a patch :)
337  */
339  GetBitContext gb= s->gb;
340 
341  int cbpc, i, pred_x, pred_y, mx, my;
342  int16_t *mot_val;
343  const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
344  const int stride= s->b8_stride*2;
345 
346  for(i=0; i<4; i++)
347  s->block_index[i]+= 2;
348  for(i=4; i<6; i++)
349  s->block_index[i]+= 1;
350  s->mb_x++;
351 
353 
354  do{
355  if (get_bits1(&s->gb)) {
356  /* skip mb */
357  mot_val = s->current_picture.motion_val[0][s->block_index[0]];
358  mot_val[0 ]= mot_val[2 ]=
359  mot_val[0+stride]= mot_val[2+stride]= 0;
360  mot_val[1 ]= mot_val[3 ]=
361  mot_val[1+stride]= mot_val[3+stride]= 0;
362 
364  goto end;
365  }
366  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
367  }while(cbpc == 20);
368 
369  if(cbpc & 4){
371  }else{
372  get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
373  if (cbpc & 8) {
374  if(s->modified_quant){
375  if(get_bits1(&s->gb)) skip_bits(&s->gb, 1);
376  else skip_bits(&s->gb, 5);
377  }else
378  skip_bits(&s->gb, 2);
379  }
380 
381  if ((cbpc & 16) == 0) {
383  /* 16x16 motion prediction */
384  mot_val= ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
385  if (s->umvplus)
386  mx = h263p_decode_umotion(s, pred_x);
387  else
388  mx = ff_h263_decode_motion(s, pred_x, 1);
389 
390  if (s->umvplus)
391  my = h263p_decode_umotion(s, pred_y);
392  else
393  my = ff_h263_decode_motion(s, pred_y, 1);
394 
395  mot_val[0 ]= mot_val[2 ]=
396  mot_val[0+stride]= mot_val[2+stride]= mx;
397  mot_val[1 ]= mot_val[3 ]=
398  mot_val[1+stride]= mot_val[3+stride]= my;
399  } else {
401  for(i=0;i<4;i++) {
402  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
403  if (s->umvplus)
404  mx = h263p_decode_umotion(s, pred_x);
405  else
406  mx = ff_h263_decode_motion(s, pred_x, 1);
407 
408  if (s->umvplus)
409  my = h263p_decode_umotion(s, pred_y);
410  else
411  my = ff_h263_decode_motion(s, pred_y, 1);
412  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
413  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
414  mot_val[0] = mx;
415  mot_val[1] = my;
416  }
417  }
418  }
419 end:
420 
421  for(i=0; i<4; i++)
422  s->block_index[i]-= 2;
423  for(i=4; i<6; i++)
424  s->block_index[i]-= 1;
425  s->mb_x--;
426 
427  s->gb= gb;
428 }
429 
431  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
432 
433  if(s->modified_quant){
434  if(get_bits1(&s->gb))
436  else
437  s->qscale= get_bits(&s->gb, 5);
438  }else
439  s->qscale += quant_tab[get_bits(&s->gb, 2)];
440  ff_set_qscale(s, s->qscale);
441 }
442 
443 static int h263_decode_block(MpegEncContext * s, int16_t * block,
444  int n, int coded)
445 {
446  int level, i, j, run;
447  RLTable *rl = &ff_h263_rl_inter;
448  const uint8_t *scan_table;
449  GetBitContext gb= s->gb;
450 
451  scan_table = s->intra_scantable.permutated;
452  if (s->h263_aic && s->mb_intra) {
453  rl = &ff_rl_intra_aic;
454  i = 0;
455  if (s->ac_pred) {
456  if (s->h263_aic_dir)
457  scan_table = s->intra_v_scantable.permutated; /* left */
458  else
459  scan_table = s->intra_h_scantable.permutated; /* top */
460  }
461  } else if (s->mb_intra) {
462  /* DC coef */
464  if (s->rv10_version == 3 && s->pict_type == AV_PICTURE_TYPE_I) {
465  int component, diff;
466  component = (n <= 3 ? 0 : n - 4 + 1);
467  level = s->last_dc[component];
468  if (s->rv10_first_dc_coded[component]) {
469  diff = ff_rv_decode_dc(s, n);
470  if (diff == 0xffff)
471  return -1;
472  level += diff;
473  level = level & 0xff; /* handle wrap round */
474  s->last_dc[component] = level;
475  } else {
476  s->rv10_first_dc_coded[component] = 1;
477  }
478  } else {
479  level = get_bits(&s->gb, 8);
480  if (level == 255)
481  level = 128;
482  }
483  }else{
484  level = get_bits(&s->gb, 8);
485  if((level&0x7F) == 0){
486  av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y);
488  return -1;
489  }
490  if (level == 255)
491  level = 128;
492  }
493  block[0] = level;
494  i = 1;
495  } else {
496  i = 0;
497  }
498  if (!coded) {
499  if (s->mb_intra && s->h263_aic)
500  goto not_coded;
501  s->block_last_index[n] = i - 1;
502  return 0;
503  }
504 retry:
505  {
506  OPEN_READER(re, &s->gb);
507  i--; // offset by -1 to allow direct indexing of scan_table
508  for(;;) {
509  UPDATE_CACHE(re, &s->gb);
510  GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
511  if (run == 66) {
512  if (level){
513  CLOSE_READER(re, &s->gb);
514  av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
515  return -1;
516  }
517  /* escape */
518  if (CONFIG_FLV_DECODER && s->h263_flv > 1) {
519  int is11 = SHOW_UBITS(re, &s->gb, 1);
520  SKIP_CACHE(re, &s->gb, 1);
521  run = SHOW_UBITS(re, &s->gb, 7) + 1;
522  if (is11) {
523  SKIP_COUNTER(re, &s->gb, 1 + 7);
524  UPDATE_CACHE(re, &s->gb);
525  level = SHOW_SBITS(re, &s->gb, 11);
526  SKIP_COUNTER(re, &s->gb, 11);
527  } else {
528  SKIP_CACHE(re, &s->gb, 7);
529  level = SHOW_SBITS(re, &s->gb, 7);
530  SKIP_COUNTER(re, &s->gb, 1 + 7 + 7);
531  }
532  } else {
533  run = SHOW_UBITS(re, &s->gb, 7) + 1;
534  SKIP_CACHE(re, &s->gb, 7);
535  level = (int8_t)SHOW_UBITS(re, &s->gb, 8);
536  SKIP_COUNTER(re, &s->gb, 7 + 8);
537  if(level == -128){
538  UPDATE_CACHE(re, &s->gb);
539  if (s->codec_id == AV_CODEC_ID_RV10) {
540  /* XXX: should patch encoder too */
541  level = SHOW_SBITS(re, &s->gb, 12);
542  SKIP_COUNTER(re, &s->gb, 12);
543  }else{
544  level = SHOW_UBITS(re, &s->gb, 5);
545  SKIP_CACHE(re, &s->gb, 5);
546  level |= SHOW_SBITS(re, &s->gb, 6) * (1<<5);
547  SKIP_COUNTER(re, &s->gb, 5 + 6);
548  }
549  }
550  }
551  } else {
552  if (SHOW_UBITS(re, &s->gb, 1))
553  level = -level;
554  SKIP_COUNTER(re, &s->gb, 1);
555  }
556  i += run;
557  if (i >= 64){
558  CLOSE_READER(re, &s->gb);
559  // redo update without last flag, revert -1 offset
560  i = i - run + ((run-1)&63) + 1;
561  if (i < 64) {
562  // only last marker, no overrun
563  block[scan_table[i]] = level;
564  break;
565  }
566  if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){
567  //Looks like a hack but no, it's the way it is supposed to work ...
568  rl = &ff_rl_intra_aic;
569  i = 0;
570  s->gb= gb;
571  s->bdsp.clear_block(block);
572  goto retry;
573  }
574  av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n", s->mb_x, s->mb_y, s->mb_intra);
575  return -1;
576  }
577  j = scan_table[i];
578  block[j] = level;
579  }
580  }
581 not_coded:
582  if (s->mb_intra && s->h263_aic) {
583  ff_h263_pred_acdc(s, block, n);
584  i = 63;
585  }
586  s->block_last_index[n] = i;
587  return 0;
588 }
589 
590 static int h263_skip_b_part(MpegEncContext *s, int cbp)
591 {
592  LOCAL_ALIGNED_32(int16_t, dblock, [64]);
593  int i, mbi;
594  int bli[6];
595 
596  /* we have to set s->mb_intra to zero to decode B-part of PB-frame correctly
597  * but real value should be restored in order to be used later (in OBMC condition)
598  */
599  mbi = s->mb_intra;
600  memcpy(bli, s->block_last_index, sizeof(bli));
601  s->mb_intra = 0;
602  for (i = 0; i < 6; i++) {
603  if (h263_decode_block(s, dblock, i, cbp&32) < 0)
604  return -1;
605  cbp+=cbp;
606  }
607  s->mb_intra = mbi;
608  memcpy(s->block_last_index, bli, sizeof(bli));
609  return 0;
610 }
611 
612 static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
613 {
614  int c, mv = 1;
615 
616  if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame
617  c = get_bits1(gb);
618  if (pb_frame == 2 && c)
619  mv = !get_bits1(gb);
620  } else { // h.263 Annex M improved PB-frame
621  mv = get_unary(gb, 0, 4) + 1;
622  c = mv & 1;
623  mv = !!(mv & 2);
624  }
625  if(c)
626  *cbpb = get_bits(gb, 6);
627  return mv;
628 }
629 
630 #define tab_size ((signed)FF_ARRAY_ELEMS(s->direct_scale_mv[0]))
631 #define tab_bias (tab_size / 2)
632 static inline void set_one_direct_mv(MpegEncContext *s, Picture *p, int i)
633 {
634  int xy = s->block_index[i];
635  uint16_t time_pp = s->pp_time;
636  uint16_t time_pb = s->pb_time;
637  int p_mx, p_my;
638 
639  p_mx = p->motion_val[0][xy][0];
640  if ((unsigned)(p_mx + tab_bias) < tab_size) {
641  s->mv[0][i][0] = s->direct_scale_mv[0][p_mx + tab_bias];
642  s->mv[1][i][0] = s->direct_scale_mv[1][p_mx + tab_bias];
643  } else {
644  s->mv[0][i][0] = p_mx * time_pb / time_pp;
645  s->mv[1][i][0] = p_mx * (time_pb - time_pp) / time_pp;
646  }
647  p_my = p->motion_val[0][xy][1];
648  if ((unsigned)(p_my + tab_bias) < tab_size) {
649  s->mv[0][i][1] = s->direct_scale_mv[0][p_my + tab_bias];
650  s->mv[1][i][1] = s->direct_scale_mv[1][p_my + tab_bias];
651  } else {
652  s->mv[0][i][1] = p_my * time_pb / time_pp;
653  s->mv[1][i][1] = p_my * (time_pb - time_pp) / time_pp;
654  }
655 }
656 
657 /**
658  * @return the mb_type
659  */
661 {
662  const int mb_index = s->mb_x + s->mb_y * s->mb_stride;
663  Picture *p = &s->next_picture;
664  int colocated_mb_type = p->mb_type[mb_index];
665  int i;
666 
667  if (s->codec_tag == AV_RL32("U263") && p->f->pict_type == AV_PICTURE_TYPE_I) {
668  p = &s->last_picture;
669  colocated_mb_type = p->mb_type[mb_index];
670  }
671 
672  if (IS_8X8(colocated_mb_type)) {
673  s->mv_type = MV_TYPE_8X8;
674  for (i = 0; i < 4; i++)
675  set_one_direct_mv(s, p, i);
677  } else {
678  set_one_direct_mv(s, p, 0);
679  s->mv[0][1][0] =
680  s->mv[0][2][0] =
681  s->mv[0][3][0] = s->mv[0][0][0];
682  s->mv[0][1][1] =
683  s->mv[0][2][1] =
684  s->mv[0][3][1] = s->mv[0][0][1];
685  s->mv[1][1][0] =
686  s->mv[1][2][0] =
687  s->mv[1][3][0] = s->mv[1][0][0];
688  s->mv[1][1][1] =
689  s->mv[1][2][1] =
690  s->mv[1][3][1] = s->mv[1][0][1];
691  s->mv_type = MV_TYPE_8X8;
692  // Note see prev line
694  }
695 }
696 
698  int16_t block[6][64])
699 {
700  int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
701  int16_t *mot_val;
702  const int xy= s->mb_x + s->mb_y * s->mb_stride;
703  int cbpb = 0, pb_mv_count = 0;
704 
705  av_assert2(!s->h263_pred);
706 
707  if (s->pict_type == AV_PICTURE_TYPE_P) {
708  do{
709  if (get_bits1(&s->gb)) {
710  /* skip mb */
711  s->mb_intra = 0;
712  for(i=0;i<6;i++)
713  s->block_last_index[i] = -1;
714  s->mv_dir = MV_DIR_FORWARD;
715  s->mv_type = MV_TYPE_16X16;
717  s->mv[0][0][0] = 0;
718  s->mv[0][0][1] = 0;
719  s->mb_skipped = !(s->obmc | s->loop_filter);
720  goto end;
721  }
722  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
723  if (cbpc < 0){
724  av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
725  return SLICE_ERROR;
726  }
727  }while(cbpc == 20);
728 
729  s->bdsp.clear_blocks(s->block[0]);
730 
731  dquant = cbpc & 8;
732  s->mb_intra = ((cbpc & 4) != 0);
733  if (s->mb_intra) goto intra;
734 
735  if(s->pb_frame && get_bits1(&s->gb))
736  pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
737  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
738 
739  if (cbpy < 0) {
740  av_log(s->avctx, AV_LOG_ERROR, "cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
741  return SLICE_ERROR;
742  }
743 
744  if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
745  cbpy ^= 0xF;
746 
747  cbp = (cbpc & 3) | (cbpy << 2);
748  if (dquant) {
750  }
751 
752  s->mv_dir = MV_DIR_FORWARD;
753  if ((cbpc & 16) == 0) {
755  /* 16x16 motion prediction */
756  s->mv_type = MV_TYPE_16X16;
757  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
758  if (s->umvplus)
759  mx = h263p_decode_umotion(s, pred_x);
760  else
761  mx = ff_h263_decode_motion(s, pred_x, 1);
762 
763  if (mx >= 0xffff)
764  return SLICE_ERROR;
765 
766  if (s->umvplus)
767  my = h263p_decode_umotion(s, pred_y);
768  else
769  my = ff_h263_decode_motion(s, pred_y, 1);
770 
771  if (my >= 0xffff)
772  return SLICE_ERROR;
773  s->mv[0][0][0] = mx;
774  s->mv[0][0][1] = my;
775 
776  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
777  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
778  } else {
780  s->mv_type = MV_TYPE_8X8;
781  for(i=0;i<4;i++) {
782  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
783  if (s->umvplus)
784  mx = h263p_decode_umotion(s, pred_x);
785  else
786  mx = ff_h263_decode_motion(s, pred_x, 1);
787  if (mx >= 0xffff)
788  return SLICE_ERROR;
789 
790  if (s->umvplus)
791  my = h263p_decode_umotion(s, pred_y);
792  else
793  my = ff_h263_decode_motion(s, pred_y, 1);
794  if (my >= 0xffff)
795  return SLICE_ERROR;
796  s->mv[0][i][0] = mx;
797  s->mv[0][i][1] = my;
798  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
799  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
800  mot_val[0] = mx;
801  mot_val[1] = my;
802  }
803  }
804  } else if(s->pict_type==AV_PICTURE_TYPE_B) {
805  int mb_type;
806  const int stride= s->b8_stride;
807  int16_t *mot_val0 = s->current_picture.motion_val[0][2 * (s->mb_x + s->mb_y * stride)];
808  int16_t *mot_val1 = s->current_picture.motion_val[1][2 * (s->mb_x + s->mb_y * stride)];
809 // const int mv_xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
810 
811  //FIXME ugly
812  mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]=
813  mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]=
814  mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]=
815  mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0;
816 
817  do{
818  mb_type= get_vlc2(&s->gb, h263_mbtype_b_vlc.table, H263_MBTYPE_B_VLC_BITS, 2);
819  if (mb_type < 0){
820  av_log(s->avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n", s->mb_x, s->mb_y);
821  return SLICE_ERROR;
822  }
823 
824  mb_type= h263_mb_type_b_map[ mb_type ];
825  }while(!mb_type);
826 
827  s->mb_intra = IS_INTRA(mb_type);
828  if(HAS_CBP(mb_type)){
829  s->bdsp.clear_blocks(s->block[0]);
830  cbpc = get_vlc2(&s->gb, cbpc_b_vlc.table, CBPC_B_VLC_BITS, 1);
831  if(s->mb_intra){
832  dquant = IS_QUANT(mb_type);
833  goto intra;
834  }
835 
836  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
837 
838  if (cbpy < 0){
839  av_log(s->avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
840  return SLICE_ERROR;
841  }
842 
843  if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
844  cbpy ^= 0xF;
845 
846  cbp = (cbpc & 3) | (cbpy << 2);
847  }else
848  cbp=0;
849 
850  av_assert2(!s->mb_intra);
851 
852  if(IS_QUANT(mb_type)){
854  }
855 
856  if(IS_DIRECT(mb_type)){
858  mb_type |= set_direct_mv(s);
859  }else{
860  s->mv_dir = 0;
862 //FIXME UMV
863 
864  if(USES_LIST(mb_type, 0)){
865  int16_t *mot_val= ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
866  s->mv_dir = MV_DIR_FORWARD;
867 
868  if (s->umvplus)
869  mx = h263p_decode_umotion(s, pred_x);
870  else
871  mx = ff_h263_decode_motion(s, pred_x, 1);
872  if (mx >= 0xffff)
873  return SLICE_ERROR;
874 
875  if (s->umvplus)
876  my = h263p_decode_umotion(s, pred_y);
877  else
878  my = ff_h263_decode_motion(s, pred_y, 1);
879  if (my >= 0xffff)
880  return SLICE_ERROR;
881 
882  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
883  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
884 
885  s->mv[0][0][0] = mx;
886  s->mv[0][0][1] = my;
887  mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
888  mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
889  }
890 
891  if(USES_LIST(mb_type, 1)){
892  int16_t *mot_val= ff_h263_pred_motion(s, 0, 1, &pred_x, &pred_y);
893  s->mv_dir |= MV_DIR_BACKWARD;
894 
895  if (s->umvplus)
896  mx = h263p_decode_umotion(s, pred_x);
897  else
898  mx = ff_h263_decode_motion(s, pred_x, 1);
899  if (mx >= 0xffff)
900  return SLICE_ERROR;
901 
902  if (s->umvplus)
903  my = h263p_decode_umotion(s, pred_y);
904  else
905  my = ff_h263_decode_motion(s, pred_y, 1);
906  if (my >= 0xffff)
907  return SLICE_ERROR;
908 
909  if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
910  skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
911 
912  s->mv[1][0][0] = mx;
913  s->mv[1][0][1] = my;
914  mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
915  mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
916  }
917  }
918 
919  s->current_picture.mb_type[xy] = mb_type;
920  } else { /* I-Frame */
921  do{
922  cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
923  if (cbpc < 0){
924  av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
925  return SLICE_ERROR;
926  }
927  }while(cbpc == 8);
928 
929  s->bdsp.clear_blocks(s->block[0]);
930 
931  dquant = cbpc & 4;
932  s->mb_intra = 1;
933 intra:
935  if (s->h263_aic) {
936  s->ac_pred = get_bits1(&s->gb);
937  if(s->ac_pred){
939 
940  s->h263_aic_dir = get_bits1(&s->gb);
941  }
942  }else
943  s->ac_pred = 0;
944 
945  if(s->pb_frame && get_bits1(&s->gb))
946  pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
947  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
948  if(cbpy<0){
949  av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
950  return SLICE_ERROR;
951  }
952  cbp = (cbpc & 3) | (cbpy << 2);
953  if (dquant) {
955  }
956 
957  pb_mv_count += !!s->pb_frame;
958  }
959 
960  while(pb_mv_count--){
961  ff_h263_decode_motion(s, 0, 1);
962  ff_h263_decode_motion(s, 0, 1);
963  }
964 
965  /* decode each block */
966  for (i = 0; i < 6; i++) {
967  if (h263_decode_block(s, block[i], i, cbp&32) < 0)
968  return -1;
969  cbp+=cbp;
970  }
971 
972  if(s->pb_frame && h263_skip_b_part(s, cbpb) < 0)
973  return -1;
974  if(s->obmc && !s->mb_intra){
975  if(s->pict_type == AV_PICTURE_TYPE_P && s->mb_x+1<s->mb_width && s->mb_num_left != 1)
976  preview_obmc(s);
977  }
978 end:
979 
980  if (get_bits_left(&s->gb) < 0)
981  return AVERROR_INVALIDDATA;
982 
983  /* per-MB end of slice check */
984  {
985  int v= show_bits(&s->gb, 16);
986 
987  if (get_bits_left(&s->gb) < 16) {
988  v >>= 16 - get_bits_left(&s->gb);
989  }
990 
991  if(v==0)
992  return SLICE_END;
993  }
994 
995  return SLICE_OK;
996 }
997 
998 /* Most is hardcoded; should extend to handle all H.263 streams. */
1000 {
1001  int format, width, height, i, ret;
1002  uint32_t startcode;
1003 
1004  align_get_bits(&s->gb);
1005 
1006  if (show_bits(&s->gb, 2) == 2 && s->avctx->frame_number == 0) {
1007  av_log(s->avctx, AV_LOG_WARNING, "Header looks like RTP instead of H.263\n");
1008  }
1009 
1010  startcode= get_bits(&s->gb, 22-8);
1011 
1012  for(i= get_bits_left(&s->gb); i>24; i-=8) {
1013  startcode = ((startcode << 8) | get_bits(&s->gb, 8)) & 0x003FFFFF;
1014 
1015  if(startcode == 0x20)
1016  break;
1017  }
1018 
1019  if (startcode != 0x20) {
1020  av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
1021  return -1;
1022  }
1023  /* temporal reference */
1024  i = get_bits(&s->gb, 8); /* picture timestamp */
1025 
1026  i -= (i - (s->picture_number & 0xFF) + 128) & ~0xFF;
1027 
1028  s->picture_number= (s->picture_number&~0xFF) + i;
1029 
1030  /* PTYPE starts here */
1031  if (check_marker(s->avctx, &s->gb, "in PTYPE") != 1) {
1032  return -1;
1033  }
1034  if (get_bits1(&s->gb) != 0) {
1035  av_log(s->avctx, AV_LOG_ERROR, "Bad H.263 id\n");
1036  return -1; /* H.263 id */
1037  }
1038  skip_bits1(&s->gb); /* split screen off */
1039  skip_bits1(&s->gb); /* camera off */
1040  skip_bits1(&s->gb); /* freeze picture release off */
1041 
1042  format = get_bits(&s->gb, 3);
1043  /*
1044  0 forbidden
1045  1 sub-QCIF
1046  10 QCIF
1047  7 extended PTYPE (PLUSPTYPE)
1048  */
1049 
1050  if (format != 7 && format != 6) {
1051  s->h263_plus = 0;
1052  /* H.263v1 */
1053  width = ff_h263_format[format][0];
1054  height = ff_h263_format[format][1];
1055  if (!width)
1056  return -1;
1057 
1059 
1060  s->h263_long_vectors = get_bits1(&s->gb);
1061 
1062  if (get_bits1(&s->gb) != 0) {
1063  av_log(s->avctx, AV_LOG_ERROR, "H.263 SAC not supported\n");
1064  return -1; /* SAC: off */
1065  }
1066  s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
1067  s->unrestricted_mv = s->h263_long_vectors || s->obmc;
1068 
1069  s->pb_frame = get_bits1(&s->gb);
1070  s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
1071  skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */
1072 
1073  s->width = width;
1074  s->height = height;
1075  s->avctx->sample_aspect_ratio= (AVRational){12,11};
1076  s->avctx->framerate = (AVRational){ 30000, 1001 };
1077  } else {
1078  int ufep;
1079 
1080  /* H.263v2 */
1081  s->h263_plus = 1;
1082  ufep = get_bits(&s->gb, 3); /* Update Full Extended PTYPE */
1083 
1084  /* ufep other than 0 and 1 are reserved */
1085  if (ufep == 1) {
1086  /* OPPTYPE */
1087  format = get_bits(&s->gb, 3);
1088  ff_dlog(s->avctx, "ufep=1, format: %d\n", format);
1089  s->custom_pcf= get_bits1(&s->gb);
1090  s->umvplus = get_bits1(&s->gb); /* Unrestricted Motion Vector */
1091  if (get_bits1(&s->gb) != 0) {
1092  av_log(s->avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n");
1093  }
1094  s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
1095  s->h263_aic = get_bits1(&s->gb); /* Advanced Intra Coding (AIC) */
1096  s->loop_filter= get_bits1(&s->gb);
1097  s->unrestricted_mv = s->umvplus || s->obmc || s->loop_filter;
1098  if(s->avctx->lowres)
1099  s->loop_filter = 0;
1100 
1102  if (get_bits1(&s->gb) != 0) {
1103  av_log(s->avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n");
1104  }
1105  if (get_bits1(&s->gb) != 0) {
1106  av_log(s->avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n");
1107  }
1108  s->alt_inter_vlc= get_bits1(&s->gb);
1109  s->modified_quant= get_bits1(&s->gb);
1110  if(s->modified_quant)
1112 
1113  skip_bits(&s->gb, 1); /* Prevent start code emulation */
1114 
1115  skip_bits(&s->gb, 3); /* Reserved */
1116  } else if (ufep != 0) {
1117  av_log(s->avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep);
1118  return -1;
1119  }
1120 
1121  /* MPPTYPE */
1122  s->pict_type = get_bits(&s->gb, 3);
1123  switch(s->pict_type){
1124  case 0: s->pict_type= AV_PICTURE_TYPE_I;break;
1125  case 1: s->pict_type= AV_PICTURE_TYPE_P;break;
1126  case 2: s->pict_type= AV_PICTURE_TYPE_P;s->pb_frame = 3;break;
1127  case 3: s->pict_type= AV_PICTURE_TYPE_B;break;
1128  case 7: s->pict_type= AV_PICTURE_TYPE_I;break; //ZYGO
1129  default:
1130  return -1;
1131  }
1132  skip_bits(&s->gb, 2);
1133  s->no_rounding = get_bits1(&s->gb);
1134  skip_bits(&s->gb, 4);
1135 
1136  /* Get the picture dimensions */
1137  if (ufep) {
1138  if (format == 6) {
1139  /* Custom Picture Format (CPFMT) */
1140  s->aspect_ratio_info = get_bits(&s->gb, 4);
1141  ff_dlog(s->avctx, "aspect: %d\n", s->aspect_ratio_info);
1142  /* aspect ratios:
1143  0 - forbidden
1144  1 - 1:1
1145  2 - 12:11 (CIF 4:3)
1146  3 - 10:11 (525-type 4:3)
1147  4 - 16:11 (CIF 16:9)
1148  5 - 40:33 (525-type 16:9)
1149  6-14 - reserved
1150  */
1151  width = (get_bits(&s->gb, 9) + 1) * 4;
1152  check_marker(s->avctx, &s->gb, "in dimensions");
1153  height = get_bits(&s->gb, 9) * 4;
1154  ff_dlog(s->avctx, "\nH.263+ Custom picture: %dx%d\n",width,height);
1156  /* expected dimensions */
1157  s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8);
1158  s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8);
1159  }else{
1161  }
1162  } else {
1163  width = ff_h263_format[format][0];
1164  height = ff_h263_format[format][1];
1165  s->avctx->sample_aspect_ratio= (AVRational){12,11};
1166  }
1168  if ((width == 0) || (height == 0))
1169  return -1;
1170  s->width = width;
1171  s->height = height;
1172 
1173  if(s->custom_pcf){
1174  int gcd;
1175  s->avctx->framerate.num = 1800000;
1176  s->avctx->framerate.den = 1000 + get_bits1(&s->gb);
1177  s->avctx->framerate.den *= get_bits(&s->gb, 7);
1178  if(s->avctx->framerate.den == 0){
1179  av_log(s, AV_LOG_ERROR, "zero framerate\n");
1180  return -1;
1181  }
1182  gcd= av_gcd(s->avctx->framerate.den, s->avctx->framerate.num);
1183  s->avctx->framerate.den /= gcd;
1184  s->avctx->framerate.num /= gcd;
1185  }else{
1186  s->avctx->framerate = (AVRational){ 30000, 1001 };
1187  }
1188  }
1189 
1190  if(s->custom_pcf){
1191  skip_bits(&s->gb, 2); //extended Temporal reference
1192  }
1193 
1194  if (ufep) {
1195  if (s->umvplus) {
1196  if(get_bits1(&s->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */
1197  skip_bits1(&s->gb);
1198  }
1199  if(s->h263_slice_structured){
1200  if (get_bits1(&s->gb) != 0) {
1201  av_log(s->avctx, AV_LOG_ERROR, "rectangular slices not supported\n");
1202  }
1203  if (get_bits1(&s->gb) != 0) {
1204  av_log(s->avctx, AV_LOG_ERROR, "unordered slices not supported\n");
1205  }
1206  }
1207  if (s->pict_type == AV_PICTURE_TYPE_B) {
1208  skip_bits(&s->gb, 4); //ELNUM
1209  if (ufep == 1) {
1210  skip_bits(&s->gb, 4); // RLNUM
1211  }
1212  }
1213  }
1214 
1215  s->qscale = get_bits(&s->gb, 5);
1216  }
1217 
1218  if ((ret = av_image_check_size(s->width, s->height, 0, s)) < 0)
1219  return ret;
1220 
1221  s->mb_width = (s->width + 15) / 16;
1222  s->mb_height = (s->height + 15) / 16;
1223  s->mb_num = s->mb_width * s->mb_height;
1224 
1225  if (s->pb_frame) {
1226  skip_bits(&s->gb, 3); /* Temporal reference for B-pictures */
1227  if (s->custom_pcf)
1228  skip_bits(&s->gb, 2); //extended Temporal reference
1229  skip_bits(&s->gb, 2); /* Quantization information for B-pictures */
1230  }
1231 
1232  if (s->pict_type!=AV_PICTURE_TYPE_B) {
1233  s->time = s->picture_number;
1234  s->pp_time = s->time - s->last_non_b_time;
1235  s->last_non_b_time = s->time;
1236  }else{
1237  s->time = s->picture_number;
1238  s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
1239  if (s->pp_time <=s->pb_time ||
1240  s->pp_time <= s->pp_time - s->pb_time ||
1241  s->pp_time <= 0){
1242  s->pp_time = 2;
1243  s->pb_time = 1;
1244  }
1246  }
1247 
1248  /* PEI */
1249  if (skip_1stop_8data_bits(&s->gb) < 0)
1250  return AVERROR_INVALIDDATA;
1251 
1252  if(s->h263_slice_structured){
1253  if (check_marker(s->avctx, &s->gb, "SEPB1") != 1) {
1254  return -1;
1255  }
1256 
1257  ff_h263_decode_mba(s);
1258 
1259  if (check_marker(s->avctx, &s->gb, "SEPB2") != 1) {
1260  return -1;
1261  }
1262  }
1263  s->f_code = 1;
1264 
1265  if (s->pict_type == AV_PICTURE_TYPE_B)
1266  s->low_delay = 0;
1267 
1268  if(s->h263_aic){
1269  s->y_dc_scale_table=
1271  }else{
1272  s->y_dc_scale_table=
1274  }
1275 
1277  if (s->pict_type == AV_PICTURE_TYPE_I && s->codec_tag == AV_RL32("ZYGO") && get_bits_left(&s->gb) >= 85 + 13*3*16 + 50){
1278  int i,j;
1279  for(i=0; i<85; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1280  av_log(s->avctx, AV_LOG_DEBUG, "\n");
1281  for(i=0; i<13; i++){
1282  for(j=0; j<3; j++){
1283  int v= get_bits(&s->gb, 8);
1284  v |= get_sbits(&s->gb, 8)<<8;
1285  av_log(s->avctx, AV_LOG_DEBUG, " %5d", v);
1286  }
1287  av_log(s->avctx, AV_LOG_DEBUG, "\n");
1288  }
1289  for(i=0; i<50; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1290  }
1291 
1292  return 0;
1293 }
static unsigned int show_bits_long(GetBitContext *s, int n)
Show 0-32 bits.
Definition: get_bits.h:405
av_cold void ff_h263_decode_init_vlc(void)
Definition: ituh263dec.c:108
int rv10_first_dc_coded[3]
Definition: mpegvideo.h:421
#define ff_tlog(ctx,...)
Definition: internal.h:75
#define SLICE_ERROR
Definition: mpegvideo.h:514
AVRational framerate
Definition: avcodec.h:3040
const char const char void * val
Definition: avisynth_c.h:771
int aspect_ratio_info
Definition: mpegvideo.h:402
int picture_number
Definition: mpegvideo.h:127
const char * s
Definition: avisynth_c.h:768
#define MB_TYPE_L1
Definition: mpegutils.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
ScanTable intra_v_scantable
Definition: mpegvideo.h:93
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
static const char * format[]
Definition: af_aiir.c:311
#define CBPY_VLC_BITS
Definition: h263.h:39
const uint8_t * y_dc_scale_table
qscale -> y_dc_scale table
Definition: mpegvideo.h:188
const uint16_t ff_mba_max[6]
Definition: h263data.c:267
#define MB_TYPE_DIRECT2
Definition: mpegutils.h:59
float re
Definition: fft.c:82
static void set_one_direct_mv(MpegEncContext *s, Picture *p, int i)
Definition: ituh263dec.c:632
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:269
#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:75
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:36
#define SKIP_COUNTER(name, gb, num)
Definition: get_bits.h:168
#define tab_bias
Definition: ituh263dec.c:631
static int check_marker(void *logctx, GetBitContext *s, const char *msg)
Definition: get_bits.h:415
RLTable ff_rl_intra_aic
Definition: h263data.c:230
int num
Numerator.
Definition: rational.h:59
enum AVCodecID codec_id
Definition: mpegvideo.h:112
#define AV_EF_COMPLIANT
consider all spec non compliances as errors
Definition: avcodec.h:2657
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:1896
#define MB_TYPE_INTRA
Definition: mpegutils.h:73
static int h263_decode_block(MpegEncContext *s, int16_t *block, int n, int coded)
Definition: ituh263dec.c:443
int studio_profile
Definition: mpegvideo.h:384
#define AV_EF_BITSTREAM
detect bitstream specification deviations
Definition: avcodec.h:2651
mpegvideo header.
#define HAS_CBP(a)
Definition: mpegutils.h:101
const uint16_t ff_h263_format[8][2]
Definition: h263data.c:238
uint8_t permutated[64]
Definition: idctdsp.h:33
uint8_t run
Definition: svq3.c:206
#define SLICE_OK
Definition: mpegvideo.h:513
int mb_num
number of MBs of a picture
Definition: mpegvideo.h:133
int stride
Definition: mace.c:144
#define MB_TYPE_INTRA4x4
Definition: mpegutils.h:51
RLTable.
Definition: rl.h:39
int qscale
QP.
Definition: mpegvideo.h:204
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:254
int h263_aic
Advanced INTRA Coding (AIC)
Definition: mpegvideo.h:87
int16_t * ff_h263_pred_motion(MpegEncContext *s, int block, int dir, int *px, int *py)
Definition: h263.c:307
Macro definitions for various function/variable attributes.
#define SLICE_START_CODE
Definition: mpegvideo.h:75
int modified_quant
Definition: mpegvideo.h:379
static int16_t block[64]
Definition: dct.c:115
#define USES_LIST(a, list)
Definition: mpegutils.h:99
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:390
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
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:64
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2599
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.
#define MB_TYPE_16x16
Definition: mpegutils.h:54
Picture current_picture
copy of the current picture structure.
Definition: mpegvideo.h:180
GetBitContext last_resync_gb
used to search for the next resync marker
Definition: mpegvideo.h:358
#define MB_TYPE_ACPRED
Definition: mpegutils.h:60
#define height
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:200
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:88
#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:392
const uint8_t ff_mba_length[7]
Definition: h263data.c:271
int mb_height
number of MBs horizontally & vertically
Definition: mpegvideo.h:129
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:2749
static int h263_skip_b_part(MpegEncContext *s, int cbp)
Definition: ituh263dec.c:590
int codec_tag
internal codec_tag upper case converted from avctx codec_tag
Definition: mpegvideo.h:120
#define av_log(a,...)
void ff_set_qscale(MpegEncContext *s, int qscale)
set qscale and update qscale dependent variables.
Definition: mpegvideo.c:2295
#define MB_TYPE_QUANT
Definition: mpegutils.h:70
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:596
#define H263_MBTYPE_B_VLC_BITS
Definition: ituh263dec.c:55
int h263_plus
H.263+ headers.
Definition: mpegvideo.h:109
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:161
#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:185
const uint8_t ff_h263_inter_MCBPC_code[28]
Definition: h263data.c:40
int16_t direct_scale_mv[2][64]
precomputed to avoid divisions in ff_mpeg4_set_direct_mv
Definition: mpegvideo.h:280
int mb_skipped
MUST BE SET only during DECODING.
Definition: mpegvideo.h:195
const uint8_t ff_modified_quant_tab[2][32]
Definition: h263data.c:252
void(* clear_blocks)(int16_t *blocks)
Definition: blockdsp.h:37
int unrestricted_mv
mv can point outside of the coded picture
Definition: mpegvideo.h:223
int ff_h263_decode_motion(MpegEncContext *s, int pred, int f_code)
Definition: ituh263dec.c:270
#define MB_TYPE_CBP
Definition: mpegutils.h:71
#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:38
uint16_t width
Definition: gdv.c:47
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.
int low_delay
no reordering needed / has no B-frames
Definition: mpegvideo.h:406
static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
Definition: ituh263dec.c:612
GetBitContext gb
Definition: mpegvideo.h:448
#define CLOSE_READER(name, gb)
Definition: get_bits.h:132
#define INIT_VLC_RL(rl, static_size)
Definition: rl.h:63
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:282
const uint8_t ff_h263_inter_MCBPC_bits[28]
Definition: h263data.c:49
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:301
#define CONFIG_MPEG4_DECODER
Definition: config.h:810
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:2642
#define FFMIN(a, b)
Definition: common.h:96
#define IS_DIRECT(a)
Definition: mpegutils.h:84
int umvplus
== H.263+ && unrestricted_mv
Definition: mpegvideo.h:375
int16_t(*[2] motion_val)[2]
Definition: mpegpicture.h:53
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)
Definition: get_bits.h:517
Picture.
Definition: mpegpicture.h:45
int size_in_bits
Definition: get_bits.h:59
static unsigned int show_bits(GetBitContext *s, int n)
Show 1-25 bits.
Definition: get_bits.h:304
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:563
#define AV_RL32
Definition: intreadwrite.h:146
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:86
int n
Definition: avisynth_c.h:684
int pb_frame
PB-frame mode (0 = none, 1 = base, 2 = improved)
Definition: mpegvideo.h:106
VLC ff_h263_cbpy_vlc
Definition: ituh263dec.c:100
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:194
static int h263p_decode_umotion(MpegEncContext *s, int pred)
Definition: ituh263dec.c:308
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 MB_TYPE_8x8
Definition: mpegutils.h:57
#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:391
#define FF_ASPECT_EXTENDED
Definition: h263.h:30
Libavcodec external API header.
int h263_flv
use flv H.263 header
Definition: mpegvideo.h:110
BlockDSPContext bdsp
Definition: mpegvideo.h:226
int debug
debug
Definition: avcodec.h:2598
const uint8_t ff_h263_intra_MCBPC_code[9]
Definition: h263data.c:34
static int set_direct_mv(MpegEncContext *s)
Definition: ituh263dec.c:660
ScanTable intra_scantable
Definition: mpegvideo.h:91
int height
picture size. must be a multiple of 16
Definition: mpegvideo.h:100
#define IS_QUANT(a)
Definition: mpegutils.h:95
#define OPEN_READER(name, gb)
Definition: get_bits.h:121
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:515
VLC ff_h263_intra_MCBPC_vlc
Definition: ituh263dec.c:98
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:321
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:346
ScanTable intra_h_scantable
Definition: mpegvideo.h:92
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:314
Rational number (pair of numerator and denominator).
Definition: rational.h:58
struct AVFrame * f
Definition: mpegpicture.h:46
#define CBPC_B_VLC_BITS
Definition: ituh263dec.c:56
RLTable ff_h263_rl_inter
Definition: h263data.c:161
#define CONFIG_FLV_DECODER
Definition: config.h:757
static VLC mv_vlc
Definition: ituh263dec.c:101
int ff_h263_resync(MpegEncContext *s)
Decode the group of blocks / video packet header / slice header (MPEG-4 Studio).
Definition: ituh263dec.c:213
#define SKIP_CACHE(name, gb, num)
Definition: get_bits.h:163
const uint8_t ff_cbpc_b_tab[4][2]
Definition: h263data.c:77
int f_code
forward MV resolution
Definition: mpegvideo.h:238
#define MB_TYPE_SKIP
Definition: mpegutils.h:62
const uint8_t ff_h263_cbpy_tab[16][2]
Definition: h263data.c:84
#define tab_size
Definition: ituh263dec.c:630
int ff_h263_decode_picture_header(MpegEncContext *s)
Definition: ituh263dec.c:999
#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:212
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:130
static void h263_decode_dquant(MpegEncContext *s)
Definition: ituh263dec.c:430
int h263_pred
use MPEG-4/H.263 ac/dc predictions
Definition: mpegvideo.h:105
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:189
uint8_t level
Definition: svq3.c:207
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:131
MpegEncContext.
Definition: mpegvideo.h:81
#define LOCAL_ALIGNED_32(t, v,...)
Definition: internal.h:137
struct AVCodecContext * avctx
Definition: mpegvideo.h:98
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:195
#define MB_TYPE_L0L1
Definition: mpegutils.h:69
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:130
void ff_h263_pred_acdc(MpegEncContext *s, int16_t *block, int n)
Definition: h263.c:220
#define TEX_VLC_BITS
Definition: dv.h:96
static int get_unary(GetBitContext *gb, int stop, int len)
Get unary code of limited length.
Definition: unary.h:33
static double c[64]
Picture last_picture
copy of the previous picture structure.
Definition: mpegvideo.h:162
Bi-dir predicted.
Definition: avutil.h:276
int den
Denominator.
Definition: rational.h:60
#define CONFIG_RV10_DECODER
Definition: config.h:861
const uint8_t * chroma_qscale_table
qscale -> chroma_qscale (H.263)
Definition: mpegvideo.h:190
#define IS_INTRA(x, y)
void * priv_data
Definition: avcodec.h:1545
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
#define IS_8X8(a)
Definition: mpegutils.h:89
int16_t(* block)[64]
points to one of the following blocks
Definition: mpegvideo.h:507
VLC_TYPE(* table)[2]
code, bits
Definition: vlc.h:28
Picture next_picture
copy of the next picture structure.
Definition: mpegvideo.h:168
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:472
int chroma_qscale
chroma QP
Definition: mpegvideo.h:205
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2204
static void preview_obmc(MpegEncContext *s)
read the next MVs for OBMC.
Definition: ituh263dec.c:338
uint32_t * mb_type
types and macros are defined in mpegutils.h
Definition: mpegpicture.h:56
int rv10_version
RV10 version: 0 or 3.
Definition: mpegvideo.h:420
static int skip_1stop_8data_bits(GetBitContext *gb)
Definition: get_bits.h:601
int h263_long_vectors
use horrible H.263v1 long vector mode
Definition: mpegvideo.h:224
#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
#define MB_TYPE_L0
Definition: mpegutils.h:67
int ff_h263_decode_mb(MpegEncContext *s, int16_t block[6][64])
Definition: ituh263dec.c:697
Predicted.
Definition: avutil.h:275
#define INTRA_MCBPC_VLC_BITS
Definition: h263.h:37
uint16_t pb_time
time distance between the last b and p,s,i frame
Definition: mpegvideo.h:393
const uint8_t ff_mvtab[33][2]
Definition: h263data.c:90