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mpeg4videodec.c
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1 /*
2  * MPEG4 decoder.
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #define UNCHECKED_BITSTREAM_READER 1
24 
25 #include "libavutil/opt.h"
26 #include "mpegvideo.h"
27 #include "mpeg4video.h"
28 #include "h263.h"
29 #include "thread.h"
30 
31 // The defines below define the number of bits that are read at once for
32 // reading vlc values. Changing these may improve speed and data cache needs
33 // be aware though that decreasing them may need the number of stages that is
34 // passed to get_vlc* to be increased.
35 #define SPRITE_TRAJ_VLC_BITS 6
36 #define DC_VLC_BITS 9
37 #define MB_TYPE_B_VLC_BITS 4
38 
39 
40 static VLC dc_lum, dc_chrom;
41 static VLC sprite_trajectory;
42 static VLC mb_type_b_vlc;
43 
44 static const int mb_type_b_map[4]= {
45  MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
46  MB_TYPE_L0L1 | MB_TYPE_16x16,
47  MB_TYPE_L1 | MB_TYPE_16x16,
48  MB_TYPE_L0 | MB_TYPE_16x16,
49 };
50 
51 /**
52  * Predict the ac.
53  * @param n block index (0-3 are luma, 4-5 are chroma)
54  * @param dir the ac prediction direction
55  */
56 void ff_mpeg4_pred_ac(MpegEncContext * s, int16_t *block, int n,
57  int dir)
58 {
59  int i;
60  int16_t *ac_val, *ac_val1;
61  int8_t * const qscale_table = s->current_picture.f.qscale_table;
62 
63  /* find prediction */
64  ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
65  ac_val1 = ac_val;
66  if (s->ac_pred) {
67  if (dir == 0) {
68  const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
69  /* left prediction */
70  ac_val -= 16;
71 
72  if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
73  /* same qscale */
74  for(i=1;i<8;i++) {
75  block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
76  }
77  }else{
78  /* different qscale, we must rescale */
79  for(i=1;i<8;i++) {
80  block[s->dsp.idct_permutation[i<<3]] += ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
81  }
82  }
83  } else {
84  const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
85  /* top prediction */
86  ac_val -= 16 * s->block_wrap[n];
87 
88  if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
89  /* same qscale */
90  for(i=1;i<8;i++) {
91  block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
92  }
93  }else{
94  /* different qscale, we must rescale */
95  for(i=1;i<8;i++) {
96  block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
97  }
98  }
99  }
100  }
101  /* left copy */
102  for(i=1;i<8;i++)
103  ac_val1[i ] = block[s->dsp.idct_permutation[i<<3]];
104 
105  /* top copy */
106  for(i=1;i<8;i++)
107  ac_val1[8 + i] = block[s->dsp.idct_permutation[i ]];
108 
109 }
110 
111 /**
112  * check if the next stuff is a resync marker or the end.
113  * @return 0 if not
114  */
115 static inline int mpeg4_is_resync(MpegEncContext *s){
116  int bits_count= get_bits_count(&s->gb);
117  int v= show_bits(&s->gb, 16);
118 
119  if(s->workaround_bugs&FF_BUG_NO_PADDING && !s->resync_marker){
120  return 0;
121  }
122 
123  while(v<=0xFF){
124  if(s->pict_type==AV_PICTURE_TYPE_B || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
125  break;
126  skip_bits(&s->gb, 8+s->pict_type);
127  bits_count+= 8+s->pict_type;
128  v= show_bits(&s->gb, 16);
129  }
130 
131  if(bits_count + 8 >= s->gb.size_in_bits){
132  v>>=8;
133  v|= 0x7F >> (7-(bits_count&7));
134 
135  if(v==0x7F)
136  return s->mb_num;
137  }else{
138  if(v == ff_mpeg4_resync_prefix[bits_count&7]){
139  int len, mb_num;
140  int mb_num_bits= av_log2(s->mb_num - 1) + 1;
141  GetBitContext gb= s->gb;
142 
143  skip_bits(&s->gb, 1);
144  align_get_bits(&s->gb);
145 
146  for(len=0; len<32; len++){
147  if(get_bits1(&s->gb)) break;
148  }
149 
150  mb_num= get_bits(&s->gb, mb_num_bits);
151  if(!mb_num || mb_num > s->mb_num || get_bits_count(&s->gb)+6 > s->gb.size_in_bits)
152  mb_num= -1;
153 
154  s->gb= gb;
155 
156  if(len>=ff_mpeg4_get_video_packet_prefix_length(s))
157  return mb_num;
158  }
159  }
160  return 0;
161 }
162 
163 static int mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
164 {
165  int i;
166  int a= 2<<s->sprite_warping_accuracy;
167  int rho= 3-s->sprite_warping_accuracy;
168  int r=16/a;
169  const int vop_ref[4][2]= {{0,0}, {s->width,0}, {0, s->height}, {s->width, s->height}}; // only true for rectangle shapes
170  int d[4][2]={{0,0}, {0,0}, {0,0}, {0,0}};
171  int sprite_ref[4][2];
172  int virtual_ref[2][2];
173  int w2, h2, w3, h3;
174  int alpha=0, beta=0;
175  int w= s->width;
176  int h= s->height;
177  int min_ab;
178 
179  if(w<=0 || h<=0)
180  return -1;
181 
182  for(i=0; i<s->num_sprite_warping_points; i++){
183  int length;
184  int x=0, y=0;
185 
186  length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
187  if(length){
188  x= get_xbits(gb, length);
189  }
190  if(!(s->divx_version==500 && s->divx_build==413)) skip_bits1(gb); /* marker bit */
191 
192  length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
193  if(length){
194  y=get_xbits(gb, length);
195  }
196  skip_bits1(gb); /* marker bit */
197  s->sprite_traj[i][0]= d[i][0]= x;
198  s->sprite_traj[i][1]= d[i][1]= y;
199  }
200  for(; i<4; i++)
201  s->sprite_traj[i][0]= s->sprite_traj[i][1]= 0;
202 
203  while((1<<alpha)<w) alpha++;
204  while((1<<beta )<h) beta++; // there seems to be a typo in the mpeg4 std for the definition of w' and h'
205  w2= 1<<alpha;
206  h2= 1<<beta;
207 
208 // Note, the 4th point isn't used for GMC
209  if(s->divx_version==500 && s->divx_build==413){
210  sprite_ref[0][0]= a*vop_ref[0][0] + d[0][0];
211  sprite_ref[0][1]= a*vop_ref[0][1] + d[0][1];
212  sprite_ref[1][0]= a*vop_ref[1][0] + d[0][0] + d[1][0];
213  sprite_ref[1][1]= a*vop_ref[1][1] + d[0][1] + d[1][1];
214  sprite_ref[2][0]= a*vop_ref[2][0] + d[0][0] + d[2][0];
215  sprite_ref[2][1]= a*vop_ref[2][1] + d[0][1] + d[2][1];
216  } else {
217  sprite_ref[0][0]= (a>>1)*(2*vop_ref[0][0] + d[0][0]);
218  sprite_ref[0][1]= (a>>1)*(2*vop_ref[0][1] + d[0][1]);
219  sprite_ref[1][0]= (a>>1)*(2*vop_ref[1][0] + d[0][0] + d[1][0]);
220  sprite_ref[1][1]= (a>>1)*(2*vop_ref[1][1] + d[0][1] + d[1][1]);
221  sprite_ref[2][0]= (a>>1)*(2*vop_ref[2][0] + d[0][0] + d[2][0]);
222  sprite_ref[2][1]= (a>>1)*(2*vop_ref[2][1] + d[0][1] + d[2][1]);
223  }
224 /* sprite_ref[3][0]= (a>>1)*(2*vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
225  sprite_ref[3][1]= (a>>1)*(2*vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
226 
227 // this is mostly identical to the mpeg4 std (and is totally unreadable because of that ...)
228 // perhaps it should be reordered to be more readable ...
229 // the idea behind this virtual_ref mess is to be able to use shifts later per pixel instead of divides
230 // so the distance between points is converted from w&h based to w2&h2 based which are of the 2^x form
231  virtual_ref[0][0]= 16*(vop_ref[0][0] + w2)
232  + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + w2*(r*sprite_ref[1][0] - 16*vop_ref[1][0])),w);
233  virtual_ref[0][1]= 16*vop_ref[0][1]
234  + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + w2*(r*sprite_ref[1][1] - 16*vop_ref[1][1])),w);
235  virtual_ref[1][0]= 16*vop_ref[0][0]
236  + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + h2*(r*sprite_ref[2][0] - 16*vop_ref[2][0])),h);
237  virtual_ref[1][1]= 16*(vop_ref[0][1] + h2)
238  + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + h2*(r*sprite_ref[2][1] - 16*vop_ref[2][1])),h);
239 
240  switch(s->num_sprite_warping_points)
241  {
242  case 0:
243  s->sprite_offset[0][0]= 0;
244  s->sprite_offset[0][1]= 0;
245  s->sprite_offset[1][0]= 0;
246  s->sprite_offset[1][1]= 0;
247  s->sprite_delta[0][0]= a;
248  s->sprite_delta[0][1]= 0;
249  s->sprite_delta[1][0]= 0;
250  s->sprite_delta[1][1]= a;
251  s->sprite_shift[0]= 0;
252  s->sprite_shift[1]= 0;
253  break;
254  case 1: //GMC only
255  s->sprite_offset[0][0]= sprite_ref[0][0] - a*vop_ref[0][0];
256  s->sprite_offset[0][1]= sprite_ref[0][1] - a*vop_ref[0][1];
257  s->sprite_offset[1][0]= ((sprite_ref[0][0]>>1)|(sprite_ref[0][0]&1)) - a*(vop_ref[0][0]/2);
258  s->sprite_offset[1][1]= ((sprite_ref[0][1]>>1)|(sprite_ref[0][1]&1)) - a*(vop_ref[0][1]/2);
259  s->sprite_delta[0][0]= a;
260  s->sprite_delta[0][1]= 0;
261  s->sprite_delta[1][0]= 0;
262  s->sprite_delta[1][1]= a;
263  s->sprite_shift[0]= 0;
264  s->sprite_shift[1]= 0;
265  break;
266  case 2:
267  s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+rho))
268  + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][0])
269  + ( r*sprite_ref[0][1] - virtual_ref[0][1])*(-vop_ref[0][1])
270  + (1<<(alpha+rho-1));
271  s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+rho))
272  + (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-vop_ref[0][0])
273  + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][1])
274  + (1<<(alpha+rho-1));
275  s->sprite_offset[1][0]= ( (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][0] + 1)
276  +( r*sprite_ref[0][1] - virtual_ref[0][1])*(-2*vop_ref[0][1] + 1)
277  +2*w2*r*sprite_ref[0][0]
278  - 16*w2
279  + (1<<(alpha+rho+1)));
280  s->sprite_offset[1][1]= ( (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-2*vop_ref[0][0] + 1)
281  +(-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][1] + 1)
282  +2*w2*r*sprite_ref[0][1]
283  - 16*w2
284  + (1<<(alpha+rho+1)));
285  s->sprite_delta[0][0]= (-r*sprite_ref[0][0] + virtual_ref[0][0]);
286  s->sprite_delta[0][1]= (+r*sprite_ref[0][1] - virtual_ref[0][1]);
287  s->sprite_delta[1][0]= (-r*sprite_ref[0][1] + virtual_ref[0][1]);
288  s->sprite_delta[1][1]= (-r*sprite_ref[0][0] + virtual_ref[0][0]);
289 
290  s->sprite_shift[0]= alpha+rho;
291  s->sprite_shift[1]= alpha+rho+2;
292  break;
293  case 3:
294  min_ab= FFMIN(alpha, beta);
295  w3= w2>>min_ab;
296  h3= h2>>min_ab;
297  s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+beta+rho-min_ab))
298  + (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-vop_ref[0][0])
299  + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-vop_ref[0][1])
300  + (1<<(alpha+beta+rho-min_ab-1));
301  s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+beta+rho-min_ab))
302  + (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-vop_ref[0][0])
303  + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-vop_ref[0][1])
304  + (1<<(alpha+beta+rho-min_ab-1));
305  s->sprite_offset[1][0]= (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-2*vop_ref[0][0] + 1)
306  + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-2*vop_ref[0][1] + 1)
307  + 2*w2*h3*r*sprite_ref[0][0]
308  - 16*w2*h3
309  + (1<<(alpha+beta+rho-min_ab+1));
310  s->sprite_offset[1][1]= (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-2*vop_ref[0][0] + 1)
311  + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-2*vop_ref[0][1] + 1)
312  + 2*w2*h3*r*sprite_ref[0][1]
313  - 16*w2*h3
314  + (1<<(alpha+beta+rho-min_ab+1));
315  s->sprite_delta[0][0]= (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3;
316  s->sprite_delta[0][1]= (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3;
317  s->sprite_delta[1][0]= (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3;
318  s->sprite_delta[1][1]= (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3;
319 
320  s->sprite_shift[0]= alpha + beta + rho - min_ab;
321  s->sprite_shift[1]= alpha + beta + rho - min_ab + 2;
322  break;
323  }
324  /* try to simplify the situation */
325  if( s->sprite_delta[0][0] == a<<s->sprite_shift[0]
326  && s->sprite_delta[0][1] == 0
327  && s->sprite_delta[1][0] == 0
328  && s->sprite_delta[1][1] == a<<s->sprite_shift[0])
329  {
330  s->sprite_offset[0][0]>>=s->sprite_shift[0];
331  s->sprite_offset[0][1]>>=s->sprite_shift[0];
332  s->sprite_offset[1][0]>>=s->sprite_shift[1];
333  s->sprite_offset[1][1]>>=s->sprite_shift[1];
334  s->sprite_delta[0][0]= a;
335  s->sprite_delta[0][1]= 0;
336  s->sprite_delta[1][0]= 0;
337  s->sprite_delta[1][1]= a;
338  s->sprite_shift[0]= 0;
339  s->sprite_shift[1]= 0;
340  s->real_sprite_warping_points=1;
341  }
342  else{
343  int shift_y= 16 - s->sprite_shift[0];
344  int shift_c= 16 - s->sprite_shift[1];
345  for(i=0; i<2; i++){
346  s->sprite_offset[0][i]<<= shift_y;
347  s->sprite_offset[1][i]<<= shift_c;
348  s->sprite_delta[0][i]<<= shift_y;
349  s->sprite_delta[1][i]<<= shift_y;
350  s->sprite_shift[i]= 16;
351  }
352  s->real_sprite_warping_points= s->num_sprite_warping_points;
353  }
354  return 0;
355 }
356 
357 /**
358  * Decode the next video packet.
359  * @return <0 if something went wrong
360  */
361 int ff_mpeg4_decode_video_packet_header(MpegEncContext *s)
362 {
363  int mb_num_bits= av_log2(s->mb_num - 1) + 1;
364  int header_extension=0, mb_num, len;
365 
366  /* is there enough space left for a video packet + header */
367  if( get_bits_count(&s->gb) > s->gb.size_in_bits-20) return -1;
368 
369  for(len=0; len<32; len++){
370  if(get_bits1(&s->gb)) break;
371  }
372 
373  if(len!=ff_mpeg4_get_video_packet_prefix_length(s)){
374  av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
375  return -1;
376  }
377 
378  if(s->shape != RECT_SHAPE){
379  header_extension= get_bits1(&s->gb);
380  //FIXME more stuff here
381  }
382 
383  mb_num= get_bits(&s->gb, mb_num_bits);
384  if(mb_num>=s->mb_num){
385  av_log(s->avctx, AV_LOG_ERROR, "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
386  return -1;
387  }
388 
389  s->mb_x= mb_num % s->mb_width;
390  s->mb_y= mb_num / s->mb_width;
391 
392  if(s->shape != BIN_ONLY_SHAPE){
393  int qscale= get_bits(&s->gb, s->quant_precision);
394  if(qscale)
395  s->chroma_qscale=s->qscale= qscale;
396  }
397 
398  if(s->shape == RECT_SHAPE){
399  header_extension= get_bits1(&s->gb);
400  }
401  if(header_extension){
402  int time_incr=0;
403 
404  while (get_bits1(&s->gb) != 0)
405  time_incr++;
406 
407  check_marker(&s->gb, "before time_increment in video packed header");
408  skip_bits(&s->gb, s->time_increment_bits); /* time_increment */
409  check_marker(&s->gb, "before vop_coding_type in video packed header");
410 
411  skip_bits(&s->gb, 2); /* vop coding type */
412  //FIXME not rect stuff here
413 
414  if(s->shape != BIN_ONLY_SHAPE){
415  skip_bits(&s->gb, 3); /* intra dc vlc threshold */
416 //FIXME don't just ignore everything
417  if(s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
418  if(mpeg4_decode_sprite_trajectory(s, &s->gb) < 0)
419  return -1;
420  av_log(s->avctx, AV_LOG_ERROR, "untested\n");
421  }
422 
423  //FIXME reduced res stuff here
424 
425  if (s->pict_type != AV_PICTURE_TYPE_I) {
426  int f_code = get_bits(&s->gb, 3); /* fcode_for */
427  if(f_code==0){
428  av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (f_code=0)\n");
429  }
430  }
431  if (s->pict_type == AV_PICTURE_TYPE_B) {
432  int b_code = get_bits(&s->gb, 3);
433  if(b_code==0){
434  av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (b_code=0)\n");
435  }
436  }
437  }
438  }
439  //FIXME new-pred stuff
440 
441  return 0;
442 }
443 
444 /**
445  * Get the average motion vector for a GMC MB.
446  * @param n either 0 for the x component or 1 for y
447  * @return the average MV for a GMC MB
448  */
449 static inline int get_amv(MpegEncContext *s, int n){
450  int x, y, mb_v, sum, dx, dy, shift;
451  int len = 1 << (s->f_code + 4);
452  const int a= s->sprite_warping_accuracy;
453 
454  if(s->workaround_bugs & FF_BUG_AMV)
455  len >>= s->quarter_sample;
456 
457  if(s->real_sprite_warping_points==1){
458  if(s->divx_version==500 && s->divx_build==413)
459  sum= s->sprite_offset[0][n] / (1<<(a - s->quarter_sample));
460  else
461  sum= RSHIFT(s->sprite_offset[0][n]<<s->quarter_sample, a);
462  }else{
463  dx= s->sprite_delta[n][0];
464  dy= s->sprite_delta[n][1];
465  shift= s->sprite_shift[0];
466  if(n) dy -= 1<<(shift + a + 1);
467  else dx -= 1<<(shift + a + 1);
468  mb_v= s->sprite_offset[0][n] + dx*s->mb_x*16 + dy*s->mb_y*16;
469 
470  sum=0;
471  for(y=0; y<16; y++){
472  int v;
473 
474  v= mb_v + dy*y;
475  //XXX FIXME optimize
476  for(x=0; x<16; x++){
477  sum+= v>>shift;
478  v+= dx;
479  }
480  }
481  sum= RSHIFT(sum, a+8-s->quarter_sample);
482  }
483 
484  if (sum < -len) sum= -len;
485  else if (sum >= len) sum= len-1;
486 
487  return sum;
488 }
489 
490 /**
491  * Decode the dc value.
492  * @param n block index (0-3 are luma, 4-5 are chroma)
493  * @param dir_ptr the prediction direction will be stored here
494  * @return the quantized dc
495  */
496 static inline int mpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
497 {
498  int level, code;
499 
500  if (n < 4)
501  code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
502  else
503  code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
504  if (code < 0 || code > 9 /* && s->nbit<9 */){
505  av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
506  return -1;
507  }
508  if (code == 0) {
509  level = 0;
510  } else {
511  if(IS_3IV1){
512  if(code==1)
513  level= 2*get_bits1(&s->gb)-1;
514  else{
515  if(get_bits1(&s->gb))
516  level = get_bits(&s->gb, code-1) + (1<<(code-1));
517  else
518  level = -get_bits(&s->gb, code-1) - (1<<(code-1));
519  }
520  }else{
521  level = get_xbits(&s->gb, code);
522  }
523 
524  if (code > 8){
525  if(get_bits1(&s->gb)==0){ /* marker */
526  if(s->err_recognition&(AV_EF_BITSTREAM|AV_EF_COMPLIANT)){
527  av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
528  return -1;
529  }
530  }
531  }
532  }
533 
534  return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
535 }
536 
537 /**
538  * Decode first partition.
539  * @return number of MBs decoded or <0 if an error occurred
540  */
541 static int mpeg4_decode_partition_a(MpegEncContext *s){
542  int mb_num;
543  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
544 
545  /* decode first partition */
546  mb_num=0;
547  s->first_slice_line=1;
548  for(; s->mb_y<s->mb_height; s->mb_y++){
549  ff_init_block_index(s);
550  for(; s->mb_x<s->mb_width; s->mb_x++){
551  const int xy= s->mb_x + s->mb_y*s->mb_stride;
552  int cbpc;
553  int dir=0;
554 
555  mb_num++;
556  ff_update_block_index(s);
557  if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
558  s->first_slice_line=0;
559 
560  if(s->pict_type==AV_PICTURE_TYPE_I){
561  int i;
562 
563  do{
564  if(show_bits_long(&s->gb, 19)==DC_MARKER){
565  return mb_num-1;
566  }
567 
568  cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
569  if (cbpc < 0){
570  av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
571  return -1;
572  }
573  }while(cbpc == 8);
574 
575  s->cbp_table[xy]= cbpc & 3;
576  s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
577  s->mb_intra = 1;
578 
579  if(cbpc & 4) {
580  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
581  }
582  s->current_picture.f.qscale_table[xy]= s->qscale;
583 
584  s->mbintra_table[xy]= 1;
585  for(i=0; i<6; i++){
586  int dc_pred_dir;
587  int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
588  if(dc < 0){
589  av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
590  return -1;
591  }
592  dir<<=1;
593  if(dc_pred_dir) dir|=1;
594  }
595  s->pred_dir_table[xy]= dir;
596  }else{ /* P/S_TYPE */
597  int mx, my, pred_x, pred_y, bits;
598  int16_t * const mot_val = s->current_picture.f.motion_val[0][s->block_index[0]];
599  const int stride= s->b8_stride*2;
600 
601 try_again:
602  bits= show_bits(&s->gb, 17);
603  if(bits==MOTION_MARKER){
604  return mb_num-1;
605  }
606  skip_bits1(&s->gb);
607  if(bits&0x10000){
608  /* skip mb */
609  if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
610  s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
611  mx= get_amv(s, 0);
612  my= get_amv(s, 1);
613  }else{
614  s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
615  mx=my=0;
616  }
617  mot_val[0 ]= mot_val[2 ]=
618  mot_val[0+stride]= mot_val[2+stride]= mx;
619  mot_val[1 ]= mot_val[3 ]=
620  mot_val[1+stride]= mot_val[3+stride]= my;
621 
622  if(s->mbintra_table[xy])
623  ff_clean_intra_table_entries(s);
624  continue;
625  }
626 
627  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
628  if (cbpc < 0){
629  av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
630  return -1;
631  }
632  if(cbpc == 20)
633  goto try_again;
634 
635  s->cbp_table[xy]= cbpc&(8+3); //8 is dquant
636 
637  s->mb_intra = ((cbpc & 4) != 0);
638 
639  if(s->mb_intra){
640  s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
641  s->mbintra_table[xy]= 1;
642  mot_val[0 ]= mot_val[2 ]=
643  mot_val[0+stride]= mot_val[2+stride]= 0;
644  mot_val[1 ]= mot_val[3 ]=
645  mot_val[1+stride]= mot_val[3+stride]= 0;
646  }else{
647  if(s->mbintra_table[xy])
648  ff_clean_intra_table_entries(s);
649 
650  if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
651  s->mcsel= get_bits1(&s->gb);
652  else s->mcsel= 0;
653 
654  if ((cbpc & 16) == 0) {
655  /* 16x16 motion prediction */
656 
657  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
658  if(!s->mcsel){
659  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
660  if (mx >= 0xffff)
661  return -1;
662 
663  my = ff_h263_decode_motion(s, pred_y, s->f_code);
664  if (my >= 0xffff)
665  return -1;
666  s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
667  } else {
668  mx = get_amv(s, 0);
669  my = get_amv(s, 1);
670  s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
671  }
672 
673  mot_val[0 ]= mot_val[2 ] =
674  mot_val[0+stride]= mot_val[2+stride]= mx;
675  mot_val[1 ]= mot_val[3 ]=
676  mot_val[1+stride]= mot_val[3+stride]= my;
677  } else {
678  int i;
679  s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
680  for(i=0;i<4;i++) {
681  int16_t *mot_val= ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
682  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
683  if (mx >= 0xffff)
684  return -1;
685 
686  my = ff_h263_decode_motion(s, pred_y, s->f_code);
687  if (my >= 0xffff)
688  return -1;
689  mot_val[0] = mx;
690  mot_val[1] = my;
691  }
692  }
693  }
694  }
695  }
696  s->mb_x= 0;
697  }
698 
699  return mb_num;
700 }
701 
702 /**
703  * decode second partition.
704  * @return <0 if an error occurred
705  */
706 static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count){
707  int mb_num=0;
708  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
709 
710  s->mb_x= s->resync_mb_x;
711  s->first_slice_line=1;
712  for(s->mb_y= s->resync_mb_y; mb_num < mb_count; s->mb_y++){
713  ff_init_block_index(s);
714  for(; mb_num < mb_count && s->mb_x<s->mb_width; s->mb_x++){
715  const int xy= s->mb_x + s->mb_y*s->mb_stride;
716 
717  mb_num++;
718  ff_update_block_index(s);
719  if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
720  s->first_slice_line=0;
721 
722  if(s->pict_type==AV_PICTURE_TYPE_I){
723  int ac_pred= get_bits1(&s->gb);
724  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
725  if(cbpy<0){
726  av_log(s->avctx, AV_LOG_ERROR, "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
727  return -1;
728  }
729 
730  s->cbp_table[xy]|= cbpy<<2;
731  s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
732  }else{ /* P || S_TYPE */
733  if (IS_INTRA(s->current_picture.f.mb_type[xy])) {
734  int dir=0,i;
735  int ac_pred = get_bits1(&s->gb);
736  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
737 
738  if(cbpy<0){
739  av_log(s->avctx, AV_LOG_ERROR, "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
740  return -1;
741  }
742 
743  if(s->cbp_table[xy] & 8) {
744  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
745  }
746  s->current_picture.f.qscale_table[xy] = s->qscale;
747 
748  for(i=0; i<6; i++){
749  int dc_pred_dir;
750  int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
751  if(dc < 0){
752  av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
753  return -1;
754  }
755  dir<<=1;
756  if(dc_pred_dir) dir|=1;
757  }
758  s->cbp_table[xy]&= 3; //remove dquant
759  s->cbp_table[xy]|= cbpy<<2;
760  s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
761  s->pred_dir_table[xy]= dir;
762  } else if (IS_SKIP(s->current_picture.f.mb_type[xy])) {
763  s->current_picture.f.qscale_table[xy] = s->qscale;
764  s->cbp_table[xy]= 0;
765  }else{
766  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
767 
768  if(cbpy<0){
769  av_log(s->avctx, AV_LOG_ERROR, "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
770  return -1;
771  }
772 
773  if(s->cbp_table[xy] & 8) {
774  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
775  }
776  s->current_picture.f.qscale_table[xy] = s->qscale;
777 
778  s->cbp_table[xy]&= 3; //remove dquant
779  s->cbp_table[xy]|= (cbpy^0xf)<<2;
780  }
781  }
782  }
783  if(mb_num >= mb_count) return 0;
784  s->mb_x= 0;
785  }
786  return 0;
787 }
788 
789 /**
790  * Decode the first and second partition.
791  * @return <0 if error (and sets error type in the error_status_table)
792  */
793 int ff_mpeg4_decode_partitions(MpegEncContext *s)
794 {
795  int mb_num;
796  const int part_a_error= s->pict_type==AV_PICTURE_TYPE_I ? (ER_DC_ERROR|ER_MV_ERROR) : ER_MV_ERROR;
797  const int part_a_end = s->pict_type==AV_PICTURE_TYPE_I ? (ER_DC_END |ER_MV_END) : ER_MV_END;
798 
799  mb_num= mpeg4_decode_partition_a(s);
800  if(mb_num<0){
801  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
802  return -1;
803  }
804 
805  if(s->resync_mb_x + s->resync_mb_y*s->mb_width + mb_num > s->mb_num){
806  av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
807  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
808  return -1;
809  }
810 
811  s->mb_num_left= mb_num;
812 
813  if(s->pict_type==AV_PICTURE_TYPE_I){
814  while(show_bits(&s->gb, 9) == 1)
815  skip_bits(&s->gb, 9);
816  if(get_bits_long(&s->gb, 19)!=DC_MARKER){
817  av_log(s->avctx, AV_LOG_ERROR, "marker missing after first I partition at %d %d\n", s->mb_x, s->mb_y);
818  return -1;
819  }
820  }else{
821  while(show_bits(&s->gb, 10) == 1)
822  skip_bits(&s->gb, 10);
823  if(get_bits(&s->gb, 17)!=MOTION_MARKER){
824  av_log(s->avctx, AV_LOG_ERROR, "marker missing after first P partition at %d %d\n", s->mb_x, s->mb_y);
825  return -1;
826  }
827  }
828  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, part_a_end);
829 
830  if( mpeg4_decode_partition_b(s, mb_num) < 0){
831  if(s->pict_type==AV_PICTURE_TYPE_P)
832  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_DC_ERROR);
833  return -1;
834  }else{
835  if(s->pict_type==AV_PICTURE_TYPE_P)
836  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_DC_END);
837  }
838 
839  return 0;
840 }
841 
842 /**
843  * Decode a block.
844  * @return <0 if an error occurred
845  */
846 static inline int mpeg4_decode_block(MpegEncContext * s, int16_t * block,
847  int n, int coded, int intra, int rvlc)
848 {
849  int level, i, last, run;
850  int av_uninit(dc_pred_dir);
851  RLTable * rl;
852  RL_VLC_ELEM * rl_vlc;
853  const uint8_t * scan_table;
854  int qmul, qadd;
855 
856  //Note intra & rvlc should be optimized away if this is inlined
857 
858  if(intra) {
859  if(s->use_intra_dc_vlc){
860  /* DC coef */
861  if(s->partitioned_frame){
862  level = s->dc_val[0][ s->block_index[n] ];
863  if(n<4) level= FASTDIV((level + (s->y_dc_scale>>1)), s->y_dc_scale);
864  else level= FASTDIV((level + (s->c_dc_scale>>1)), s->c_dc_scale);
865  dc_pred_dir= (s->pred_dir_table[s->mb_x + s->mb_y*s->mb_stride]<<n)&32;
866  }else{
867  level = mpeg4_decode_dc(s, n, &dc_pred_dir);
868  if (level < 0)
869  return -1;
870  }
871  block[0] = level;
872  i = 0;
873  }else{
874  i = -1;
875  ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
876  }
877  if (!coded)
878  goto not_coded;
879 
880  if(rvlc){
881  rl = &ff_rvlc_rl_intra;
882  rl_vlc = ff_rvlc_rl_intra.rl_vlc[0];
883  }else{
884  rl = &ff_mpeg4_rl_intra;
885  rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
886  }
887  if (s->ac_pred) {
888  if (dc_pred_dir == 0)
889  scan_table = s->intra_v_scantable.permutated; /* left */
890  else
891  scan_table = s->intra_h_scantable.permutated; /* top */
892  } else {
893  scan_table = s->intra_scantable.permutated;
894  }
895  qmul=1;
896  qadd=0;
897  } else {
898  i = -1;
899  if (!coded) {
900  s->block_last_index[n] = i;
901  return 0;
902  }
903  if(rvlc) rl = &ff_rvlc_rl_inter;
904  else rl = &ff_h263_rl_inter;
905 
906  scan_table = s->intra_scantable.permutated;
907 
908  if(s->mpeg_quant){
909  qmul=1;
910  qadd=0;
911  if(rvlc){
912  rl_vlc = ff_rvlc_rl_inter.rl_vlc[0];
913  }else{
914  rl_vlc = ff_h263_rl_inter.rl_vlc[0];
915  }
916  }else{
917  qmul = s->qscale << 1;
918  qadd = (s->qscale - 1) | 1;
919  if(rvlc){
920  rl_vlc = ff_rvlc_rl_inter.rl_vlc[s->qscale];
921  }else{
922  rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
923  }
924  }
925  }
926  {
927  OPEN_READER(re, &s->gb);
928  for(;;) {
929  UPDATE_CACHE(re, &s->gb);
930  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
931  if (level==0) {
932  /* escape */
933  if(rvlc){
934  if(SHOW_UBITS(re, &s->gb, 1)==0){
935  av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in rvlc esc\n");
936  return -1;
937  }; SKIP_CACHE(re, &s->gb, 1);
938 
939  last= SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
940  run= SHOW_UBITS(re, &s->gb, 6);
941  SKIP_COUNTER(re, &s->gb, 1+1+6);
942  UPDATE_CACHE(re, &s->gb);
943 
944  if(SHOW_UBITS(re, &s->gb, 1)==0){
945  av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in rvlc esc\n");
946  return -1;
947  }; SKIP_CACHE(re, &s->gb, 1);
948 
949  level= SHOW_UBITS(re, &s->gb, 11); SKIP_CACHE(re, &s->gb, 11);
950 
951  if(SHOW_UBITS(re, &s->gb, 5)!=0x10){
952  av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
953  return -1;
954  }; SKIP_CACHE(re, &s->gb, 5);
955 
956  level= level * qmul + qadd;
957  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
958  SKIP_COUNTER(re, &s->gb, 1+11+5+1);
959 
960  i+= run + 1;
961  if(last) i+=192;
962  }else{
963  int cache;
964  cache= GET_CACHE(re, &s->gb);
965 
966  if(IS_3IV1)
967  cache ^= 0xC0000000;
968 
969  if (cache&0x80000000) {
970  if (cache&0x40000000) {
971  /* third escape */
972  SKIP_CACHE(re, &s->gb, 2);
973  last= SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
974  run= SHOW_UBITS(re, &s->gb, 6);
975  SKIP_COUNTER(re, &s->gb, 2+1+6);
976  UPDATE_CACHE(re, &s->gb);
977 
978  if(IS_3IV1){
979  level= SHOW_SBITS(re, &s->gb, 12); LAST_SKIP_BITS(re, &s->gb, 12);
980  }else{
981  if(SHOW_UBITS(re, &s->gb, 1)==0){
982  av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in 3. esc\n");
983  return -1;
984  }; SKIP_CACHE(re, &s->gb, 1);
985 
986  level= SHOW_SBITS(re, &s->gb, 12); SKIP_CACHE(re, &s->gb, 12);
987 
988  if(SHOW_UBITS(re, &s->gb, 1)==0){
989  av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in 3. esc\n");
990  return -1;
991  }
992 
993  SKIP_COUNTER(re, &s->gb, 1+12+1);
994  }
995 
996 #if 0
997  if(s->error_recognition >= FF_ER_COMPLIANT){
998  const int abs_level= FFABS(level);
999  if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
1000  const int run1= run - rl->max_run[last][abs_level] - 1;
1001  if(abs_level <= rl->max_level[last][run]){
1002  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
1003  return -1;
1004  }
1005  if(s->error_recognition > FF_ER_COMPLIANT){
1006  if(abs_level <= rl->max_level[last][run]*2){
1007  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
1008  return -1;
1009  }
1010  if(run1 >= 0 && abs_level <= rl->max_level[last][run1]){
1011  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
1012  return -1;
1013  }
1014  }
1015  }
1016  }
1017 #endif
1018  if (level>0) level= level * qmul + qadd;
1019  else level= level * qmul - qadd;
1020 
1021  if((unsigned)(level + 2048) > 4095){
1022  if(s->err_recognition & (AV_EF_BITSTREAM|AV_EF_AGGRESSIVE)){
1023  if(level > 2560 || level<-2560){
1024  av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc, qp=%d\n", s->qscale);
1025  return -1;
1026  }
1027  }
1028  level= level<0 ? -2048 : 2047;
1029  }
1030 
1031  i+= run + 1;
1032  if(last) i+=192;
1033  } else {
1034  /* second escape */
1035  SKIP_BITS(re, &s->gb, 2);
1036  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1037  i+= run + rl->max_run[run>>7][level/qmul] +1; //FIXME opt indexing
1038  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1039  LAST_SKIP_BITS(re, &s->gb, 1);
1040  }
1041  } else {
1042  /* first escape */
1043  SKIP_BITS(re, &s->gb, 1);
1044  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1045  i+= run;
1046  level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
1047  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1048  LAST_SKIP_BITS(re, &s->gb, 1);
1049  }
1050  }
1051  } else {
1052  i+= run;
1053  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1054  LAST_SKIP_BITS(re, &s->gb, 1);
1055  }
1056  if (i > 62){
1057  i-= 192;
1058  if(i&(~63)){
1059  av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1060  return -1;
1061  }
1062 
1063  block[scan_table[i]] = level;
1064  break;
1065  }
1066 
1067  block[scan_table[i]] = level;
1068  }
1069  CLOSE_READER(re, &s->gb);
1070  }
1071  not_coded:
1072  if (intra) {
1073  if(!s->use_intra_dc_vlc){
1074  block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
1075 
1076  i -= i>>31; //if(i == -1) i=0;
1077  }
1078 
1079  ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
1080  if (s->ac_pred) {
1081  i = 63; /* XXX: not optimal */
1082  }
1083  }
1084  s->block_last_index[n] = i;
1085  return 0;
1086 }
1087 
1088 /**
1089  * decode partition C of one MB.
1090  * @return <0 if an error occurred
1091  */
1092 static int mpeg4_decode_partitioned_mb(MpegEncContext *s, int16_t block[6][64])
1093 {
1094  int cbp, mb_type;
1095  const int xy= s->mb_x + s->mb_y*s->mb_stride;
1096 
1097  mb_type = s->current_picture.f.mb_type[xy];
1098  cbp = s->cbp_table[xy];
1099 
1100  s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
1101 
1102  if (s->current_picture.f.qscale_table[xy] != s->qscale) {
1103  ff_set_qscale(s, s->current_picture.f.qscale_table[xy]);
1104  }
1105 
1106  if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
1107  int i;
1108  for(i=0; i<4; i++){
1109  s->mv[0][i][0] = s->current_picture.f.motion_val[0][s->block_index[i]][0];
1110  s->mv[0][i][1] = s->current_picture.f.motion_val[0][s->block_index[i]][1];
1111  }
1112  s->mb_intra = IS_INTRA(mb_type);
1113 
1114  if (IS_SKIP(mb_type)) {
1115  /* skip mb */
1116  for(i=0;i<6;i++)
1117  s->block_last_index[i] = -1;
1118  s->mv_dir = MV_DIR_FORWARD;
1119  s->mv_type = MV_TYPE_16X16;
1120  if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
1121  s->mcsel=1;
1122  s->mb_skipped = 0;
1123  }else{
1124  s->mcsel=0;
1125  s->mb_skipped = 1;
1126  }
1127  }else if(s->mb_intra){
1128  s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
1129  }else if(!s->mb_intra){
1130 // s->mcsel= 0; //FIXME do we need to init that
1131 
1132  s->mv_dir = MV_DIR_FORWARD;
1133  if (IS_8X8(mb_type)) {
1134  s->mv_type = MV_TYPE_8X8;
1135  } else {
1136  s->mv_type = MV_TYPE_16X16;
1137  }
1138  }
1139  } else { /* I-Frame */
1140  s->mb_intra = 1;
1141  s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
1142  }
1143 
1144  if (!IS_SKIP(mb_type)) {
1145  int i;
1146  s->dsp.clear_blocks(s->block[0]);
1147  /* decode each block */
1148  for (i = 0; i < 6; i++) {
1149  if(mpeg4_decode_block(s, block[i], i, cbp&32, s->mb_intra, s->rvlc) < 0){
1150  av_log(s->avctx, AV_LOG_ERROR, "texture corrupted at %d %d %d\n", s->mb_x, s->mb_y, s->mb_intra);
1151  return -1;
1152  }
1153  cbp+=cbp;
1154  }
1155  }
1156 
1157  /* per-MB end of slice check */
1158 
1159  if(--s->mb_num_left <= 0){
1160  if(mpeg4_is_resync(s))
1161  return SLICE_END;
1162  else
1163  return SLICE_NOEND;
1164  }else{
1165  if(mpeg4_is_resync(s)){
1166  const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1167  if(s->cbp_table[xy+delta])
1168  return SLICE_END;
1169  }
1170  return SLICE_OK;
1171  }
1172 }
1173 
1174 static int mpeg4_decode_mb(MpegEncContext *s,
1175  int16_t block[6][64])
1176 {
1177  int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
1178  int16_t *mot_val;
1179  static int8_t quant_tab[4] = { -1, -2, 1, 2 };
1180  const int xy= s->mb_x + s->mb_y * s->mb_stride;
1181 
1182  av_assert2(s->h263_pred);
1183 
1184  if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
1185  do{
1186  if (get_bits1(&s->gb)) {
1187  /* skip mb */
1188  s->mb_intra = 0;
1189  for(i=0;i<6;i++)
1190  s->block_last_index[i] = -1;
1191  s->mv_dir = MV_DIR_FORWARD;
1192  s->mv_type = MV_TYPE_16X16;
1193  if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
1194  s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
1195  s->mcsel=1;
1196  s->mv[0][0][0]= get_amv(s, 0);
1197  s->mv[0][0][1]= get_amv(s, 1);
1198 
1199  s->mb_skipped = 0;
1200  }else{
1201  s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
1202  s->mcsel=0;
1203  s->mv[0][0][0] = 0;
1204  s->mv[0][0][1] = 0;
1205  s->mb_skipped = 1;
1206  }
1207  goto end;
1208  }
1209  cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
1210  if (cbpc < 0){
1211  av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1212  return -1;
1213  }
1214  }while(cbpc == 20);
1215 
1216  s->dsp.clear_blocks(s->block[0]);
1217  dquant = cbpc & 8;
1218  s->mb_intra = ((cbpc & 4) != 0);
1219  if (s->mb_intra) goto intra;
1220 
1221  if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
1222  s->mcsel= get_bits1(&s->gb);
1223  else s->mcsel= 0;
1224  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
1225 
1226  cbp = (cbpc & 3) | (cbpy << 2);
1227  if (dquant) {
1228  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1229  }
1230  if((!s->progressive_sequence) && (cbp || (s->workaround_bugs&FF_BUG_XVID_ILACE)))
1231  s->interlaced_dct= get_bits1(&s->gb);
1232 
1233  s->mv_dir = MV_DIR_FORWARD;
1234  if ((cbpc & 16) == 0) {
1235  if(s->mcsel){
1236  s->current_picture.f.mb_type[xy] = MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
1237  /* 16x16 global motion prediction */
1238  s->mv_type = MV_TYPE_16X16;
1239  mx= get_amv(s, 0);
1240  my= get_amv(s, 1);
1241  s->mv[0][0][0] = mx;
1242  s->mv[0][0][1] = my;
1243  }else if((!s->progressive_sequence) && get_bits1(&s->gb)){
1244  s->current_picture.f.mb_type[xy] = MB_TYPE_16x8 | MB_TYPE_L0 | MB_TYPE_INTERLACED;
1245  /* 16x8 field motion prediction */
1246  s->mv_type= MV_TYPE_FIELD;
1247 
1248  s->field_select[0][0]= get_bits1(&s->gb);
1249  s->field_select[0][1]= get_bits1(&s->gb);
1250 
1251  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1252 
1253  for(i=0; i<2; i++){
1254  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1255  if (mx >= 0xffff)
1256  return -1;
1257 
1258  my = ff_h263_decode_motion(s, pred_y/2, s->f_code);
1259  if (my >= 0xffff)
1260  return -1;
1261 
1262  s->mv[0][i][0] = mx;
1263  s->mv[0][i][1] = my;
1264  }
1265  }else{
1266  s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
1267  /* 16x16 motion prediction */
1268  s->mv_type = MV_TYPE_16X16;
1269  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1270  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1271 
1272  if (mx >= 0xffff)
1273  return -1;
1274 
1275  my = ff_h263_decode_motion(s, pred_y, s->f_code);
1276 
1277  if (my >= 0xffff)
1278  return -1;
1279  s->mv[0][0][0] = mx;
1280  s->mv[0][0][1] = my;
1281  }
1282  } else {
1283  s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
1284  s->mv_type = MV_TYPE_8X8;
1285  for(i=0;i<4;i++) {
1286  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
1287  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1288  if (mx >= 0xffff)
1289  return -1;
1290 
1291  my = ff_h263_decode_motion(s, pred_y, s->f_code);
1292  if (my >= 0xffff)
1293  return -1;
1294  s->mv[0][i][0] = mx;
1295  s->mv[0][i][1] = my;
1296  mot_val[0] = mx;
1297  mot_val[1] = my;
1298  }
1299  }
1300  } else if(s->pict_type==AV_PICTURE_TYPE_B) {
1301  int modb1; // first bit of modb
1302  int modb2; // second bit of modb
1303  int mb_type;
1304 
1305  s->mb_intra = 0; //B-frames never contain intra blocks
1306  s->mcsel=0; // ... true gmc blocks
1307 
1308  if(s->mb_x==0){
1309  for(i=0; i<2; i++){
1310  s->last_mv[i][0][0]=
1311  s->last_mv[i][0][1]=
1312  s->last_mv[i][1][0]=
1313  s->last_mv[i][1][1]= 0;
1314  }
1315 
1316  ff_thread_await_progress(&s->next_picture_ptr->f, s->mb_y, 0);
1317  }
1318 
1319  /* if we skipped it in the future P Frame than skip it now too */
1320  s->mb_skipped = s->next_picture.f.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]; // Note, skiptab=0 if last was GMC
1321 
1322  if(s->mb_skipped){
1323  /* skip mb */
1324  for(i=0;i<6;i++)
1325  s->block_last_index[i] = -1;
1326 
1327  s->mv_dir = MV_DIR_FORWARD;
1328  s->mv_type = MV_TYPE_16X16;
1329  s->mv[0][0][0] = 0;
1330  s->mv[0][0][1] = 0;
1331  s->mv[1][0][0] = 0;
1332  s->mv[1][0][1] = 0;
1333  s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
1334  goto end;
1335  }
1336 
1337  modb1= get_bits1(&s->gb);
1338  if(modb1){
1339  mb_type= MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1; //like MB_TYPE_B_DIRECT but no vectors coded
1340  cbp=0;
1341  }else{
1342  modb2= get_bits1(&s->gb);
1343  mb_type= get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
1344  if(mb_type<0){
1345  av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
1346  return -1;
1347  }
1348  mb_type= mb_type_b_map[ mb_type ];
1349  if(modb2) cbp= 0;
1350  else{
1351  s->dsp.clear_blocks(s->block[0]);
1352  cbp= get_bits(&s->gb, 6);
1353  }
1354 
1355  if ((!IS_DIRECT(mb_type)) && cbp) {
1356  if(get_bits1(&s->gb)){
1357  ff_set_qscale(s, s->qscale + get_bits1(&s->gb)*4 - 2);
1358  }
1359  }
1360 
1361  if(!s->progressive_sequence){
1362  if(cbp)
1363  s->interlaced_dct= get_bits1(&s->gb);
1364 
1365  if(!IS_DIRECT(mb_type) && get_bits1(&s->gb)){
1366  mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
1367  mb_type &= ~MB_TYPE_16x16;
1368 
1369  if(USES_LIST(mb_type, 0)){
1370  s->field_select[0][0]= get_bits1(&s->gb);
1371  s->field_select[0][1]= get_bits1(&s->gb);
1372  }
1373  if(USES_LIST(mb_type, 1)){
1374  s->field_select[1][0]= get_bits1(&s->gb);
1375  s->field_select[1][1]= get_bits1(&s->gb);
1376  }
1377  }
1378  }
1379 
1380  s->mv_dir = 0;
1381  if((mb_type & (MB_TYPE_DIRECT2|MB_TYPE_INTERLACED)) == 0){
1382  s->mv_type= MV_TYPE_16X16;
1383 
1384  if(USES_LIST(mb_type, 0)){
1385  s->mv_dir = MV_DIR_FORWARD;
1386 
1387  mx = ff_h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
1388  my = ff_h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
1389  s->last_mv[0][1][0]= s->last_mv[0][0][0]= s->mv[0][0][0] = mx;
1390  s->last_mv[0][1][1]= s->last_mv[0][0][1]= s->mv[0][0][1] = my;
1391  }
1392 
1393  if(USES_LIST(mb_type, 1)){
1394  s->mv_dir |= MV_DIR_BACKWARD;
1395 
1396  mx = ff_h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
1397  my = ff_h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
1398  s->last_mv[1][1][0]= s->last_mv[1][0][0]= s->mv[1][0][0] = mx;
1399  s->last_mv[1][1][1]= s->last_mv[1][0][1]= s->mv[1][0][1] = my;
1400  }
1401  }else if(!IS_DIRECT(mb_type)){
1402  s->mv_type= MV_TYPE_FIELD;
1403 
1404  if(USES_LIST(mb_type, 0)){
1405  s->mv_dir = MV_DIR_FORWARD;
1406 
1407  for(i=0; i<2; i++){
1408  mx = ff_h263_decode_motion(s, s->last_mv[0][i][0] , s->f_code);
1409  my = ff_h263_decode_motion(s, s->last_mv[0][i][1]/2, s->f_code);
1410  s->last_mv[0][i][0]= s->mv[0][i][0] = mx;
1411  s->last_mv[0][i][1]= (s->mv[0][i][1] = my)*2;
1412  }
1413  }
1414 
1415  if(USES_LIST(mb_type, 1)){
1416  s->mv_dir |= MV_DIR_BACKWARD;
1417 
1418  for(i=0; i<2; i++){
1419  mx = ff_h263_decode_motion(s, s->last_mv[1][i][0] , s->b_code);
1420  my = ff_h263_decode_motion(s, s->last_mv[1][i][1]/2, s->b_code);
1421  s->last_mv[1][i][0]= s->mv[1][i][0] = mx;
1422  s->last_mv[1][i][1]= (s->mv[1][i][1] = my)*2;
1423  }
1424  }
1425  }
1426  }
1427 
1428  if(IS_DIRECT(mb_type)){
1429  if(IS_SKIP(mb_type))
1430  mx=my=0;
1431  else{
1432  mx = ff_h263_decode_motion(s, 0, 1);
1433  my = ff_h263_decode_motion(s, 0, 1);
1434  }
1435 
1436  s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
1437  mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
1438  }
1439  s->current_picture.f.mb_type[xy] = mb_type;
1440  } else { /* I-Frame */
1441  do{
1442  cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
1443  if (cbpc < 0){
1444  av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1445  return -1;
1446  }
1447  }while(cbpc == 8);
1448 
1449  dquant = cbpc & 4;
1450  s->mb_intra = 1;
1451 intra:
1452  s->ac_pred = get_bits1(&s->gb);
1453  if(s->ac_pred)
1454  s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
1455  else
1456  s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
1457 
1458  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
1459  if(cbpy<0){
1460  av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
1461  return -1;
1462  }
1463  cbp = (cbpc & 3) | (cbpy << 2);
1464 
1465  s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
1466 
1467  if (dquant) {
1468  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1469  }
1470 
1471  if(!s->progressive_sequence)
1472  s->interlaced_dct= get_bits1(&s->gb);
1473 
1474  s->dsp.clear_blocks(s->block[0]);
1475  /* decode each block */
1476  for (i = 0; i < 6; i++) {
1477  if (mpeg4_decode_block(s, block[i], i, cbp&32, 1, 0) < 0)
1478  return -1;
1479  cbp+=cbp;
1480  }
1481  goto end;
1482  }
1483 
1484  /* decode each block */
1485  for (i = 0; i < 6; i++) {
1486  if (mpeg4_decode_block(s, block[i], i, cbp&32, 0, 0) < 0)
1487  return -1;
1488  cbp+=cbp;
1489  }
1490 end:
1491 
1492  /* per-MB end of slice check */
1493  if(s->codec_id==AV_CODEC_ID_MPEG4){
1494  int next= mpeg4_is_resync(s);
1495  if(next) {
1496  if (s->mb_x + s->mb_y*s->mb_width + 1 > next && (s->avctx->err_recognition & AV_EF_AGGRESSIVE)) {
1497  return -1;
1498  } else if (s->mb_x + s->mb_y*s->mb_width + 1 >= next)
1499  return SLICE_END;
1500 
1501  if(s->pict_type==AV_PICTURE_TYPE_B){
1502  const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1503  ff_thread_await_progress(&s->next_picture_ptr->f,
1504  (s->mb_x + delta >= s->mb_width) ? FFMIN(s->mb_y+1, s->mb_height-1) : s->mb_y, 0);
1505  if (s->next_picture.f.mbskip_table[xy + delta])
1506  return SLICE_OK;
1507  }
1508 
1509  return SLICE_END;
1510  }
1511  }
1512 
1513  return SLICE_OK;
1514 }
1515 
1516 
1517 static int mpeg4_decode_gop_header(MpegEncContext * s, GetBitContext *gb){
1518  int hours, minutes, seconds;
1519 
1520  if(!show_bits(gb, 23)){
1521  av_log(s->avctx, AV_LOG_WARNING, "GOP header invalid\n");
1522  return -1;
1523  }
1524 
1525  hours= get_bits(gb, 5);
1526  minutes= get_bits(gb, 6);
1527  skip_bits1(gb);
1528  seconds= get_bits(gb, 6);
1529 
1530  s->time_base= seconds + 60*(minutes + 60*hours);
1531 
1532  skip_bits1(gb);
1533  skip_bits1(gb);
1534 
1535  return 0;
1536 }
1537 
1538 static int mpeg4_decode_profile_level(MpegEncContext * s, GetBitContext *gb){
1539 
1540  s->avctx->profile = get_bits(gb, 4);
1541  s->avctx->level = get_bits(gb, 4);
1542 
1543  // for Simple profile, level 0
1544  if (s->avctx->profile == 0 && s->avctx->level == 8) {
1545  s->avctx->level = 0;
1546  }
1547 
1548  return 0;
1549 }
1550 
1551 static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
1552  int width, height, vo_ver_id;
1553 
1554  /* vol header */
1555  skip_bits(gb, 1); /* random access */
1556  s->vo_type= get_bits(gb, 8);
1557  if (get_bits1(gb) != 0) { /* is_ol_id */
1558  vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
1559  skip_bits(gb, 3); /* vo_priority */
1560  } else {
1561  vo_ver_id = 1;
1562  }
1563  s->aspect_ratio_info= get_bits(gb, 4);
1564  if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){
1565  s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
1566  s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
1567  }else{
1568  s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
1569  }
1570 
1571  if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
1572  int chroma_format= get_bits(gb, 2);
1573  if(chroma_format!=CHROMA_420){
1574  av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
1575  }
1576  s->low_delay= get_bits1(gb);
1577  if(get_bits1(gb)){ /* vbv parameters */
1578  get_bits(gb, 15); /* first_half_bitrate */
1579  skip_bits1(gb); /* marker */
1580  get_bits(gb, 15); /* latter_half_bitrate */
1581  skip_bits1(gb); /* marker */
1582  get_bits(gb, 15); /* first_half_vbv_buffer_size */
1583  skip_bits1(gb); /* marker */
1584  get_bits(gb, 3); /* latter_half_vbv_buffer_size */
1585  get_bits(gb, 11); /* first_half_vbv_occupancy */
1586  skip_bits1(gb); /* marker */
1587  get_bits(gb, 15); /* latter_half_vbv_occupancy */
1588  skip_bits1(gb); /* marker */
1589  }
1590  }else{
1591  // set low delay flag only once the smartest? low delay detection won't be overridden
1592  if(s->picture_number==0)
1593  s->low_delay=0;
1594  }
1595 
1596  s->shape = get_bits(gb, 2); /* vol shape */
1597  if(s->shape != RECT_SHAPE) av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
1598  if(s->shape == GRAY_SHAPE && vo_ver_id != 1){
1599  av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
1600  skip_bits(gb, 4); //video_object_layer_shape_extension
1601  }
1602 
1603  check_marker(gb, "before time_increment_resolution");
1604 
1605  s->avctx->time_base.den = get_bits(gb, 16);
1606  if(!s->avctx->time_base.den){
1607  av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
1608  s->avctx->time_base.num = 0;
1609  return -1;
1610  }
1611 
1612  s->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
1613  if (s->time_increment_bits < 1)
1614  s->time_increment_bits = 1;
1615 
1616  check_marker(gb, "before fixed_vop_rate");
1617 
1618  if (get_bits1(gb) != 0) { /* fixed_vop_rate */
1619  s->avctx->time_base.num = get_bits(gb, s->time_increment_bits);
1620  }else
1621  s->avctx->time_base.num = 1;
1622 
1623  s->t_frame=0;
1624 
1625  if (s->shape != BIN_ONLY_SHAPE) {
1626  if (s->shape == RECT_SHAPE) {
1627  skip_bits1(gb); /* marker */
1628  width = get_bits(gb, 13);
1629  skip_bits1(gb); /* marker */
1630  height = get_bits(gb, 13);
1631  skip_bits1(gb); /* marker */
1632  if(width && height && !(s->width && s->codec_tag == AV_RL32("MP4S"))){ /* they should be non zero but who knows ... */
1633  if (s->width && s->height &&
1634  (s->width != width || s->height != height))
1635  s->context_reinit = 1;
1636  s->width = width;
1637  s->height = height;
1638  }
1639  }
1640 
1641  s->progressive_sequence=
1642  s->progressive_frame= get_bits1(gb)^1;
1643  s->interlaced_dct=0;
1644  if(!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
1645  av_log(s->avctx, AV_LOG_INFO, "MPEG4 OBMC not supported (very likely buggy encoder)\n"); /* OBMC Disable */
1646  if (vo_ver_id == 1) {
1647  s->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
1648  } else {
1649  s->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
1650  }
1651  if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
1652  if(s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE){
1653  if(s->vol_sprite_usage==STATIC_SPRITE){
1654  s->sprite_width = get_bits(gb, 13);
1655  skip_bits1(gb); /* marker */
1656  s->sprite_height= get_bits(gb, 13);
1657  skip_bits1(gb); /* marker */
1658  s->sprite_left = get_bits(gb, 13);
1659  skip_bits1(gb); /* marker */
1660  s->sprite_top = get_bits(gb, 13);
1661  skip_bits1(gb); /* marker */
1662  }
1663  s->num_sprite_warping_points= get_bits(gb, 6);
1664  if(s->num_sprite_warping_points > 3){
1665  av_log(s->avctx, AV_LOG_ERROR, "%d sprite_warping_points\n", s->num_sprite_warping_points);
1666  s->num_sprite_warping_points= 0;
1667  return -1;
1668  }
1669  s->sprite_warping_accuracy = get_bits(gb, 2);
1670  s->sprite_brightness_change= get_bits1(gb);
1671  if(s->vol_sprite_usage==STATIC_SPRITE)
1672  s->low_latency_sprite= get_bits1(gb);
1673  }
1674  // FIXME sadct disable bit if verid!=1 && shape not rect
1675 
1676  if (get_bits1(gb) == 1) { /* not_8_bit */
1677  s->quant_precision = get_bits(gb, 4); /* quant_precision */
1678  if(get_bits(gb, 4)!=8) av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n"); /* bits_per_pixel */
1679  if(s->quant_precision!=5) av_log(s->avctx, AV_LOG_ERROR, "quant precision %d\n", s->quant_precision);
1680  if(s->quant_precision<3 || s->quant_precision>9) {
1681  s->quant_precision = 5;
1682  }
1683  } else {
1684  s->quant_precision = 5;
1685  }
1686 
1687  // FIXME a bunch of grayscale shape things
1688 
1689  if((s->mpeg_quant=get_bits1(gb))){ /* vol_quant_type */
1690  int i, v;
1691 
1692  /* load default matrixes */
1693  for(i=0; i<64; i++){
1694  int j= s->dsp.idct_permutation[i];
1695  v= ff_mpeg4_default_intra_matrix[i];
1696  s->intra_matrix[j]= v;
1697  s->chroma_intra_matrix[j]= v;
1698 
1699  v= ff_mpeg4_default_non_intra_matrix[i];
1700  s->inter_matrix[j]= v;
1701  s->chroma_inter_matrix[j]= v;
1702  }
1703 
1704  /* load custom intra matrix */
1705  if(get_bits1(gb)){
1706  int last=0;
1707  for(i=0; i<64; i++){
1708  int j;
1709  v= get_bits(gb, 8);
1710  if(v==0) break;
1711 
1712  last= v;
1713  j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1714  s->intra_matrix[j]= v;
1715  s->chroma_intra_matrix[j]= v;
1716  }
1717 
1718  /* replicate last value */
1719  for(; i<64; i++){
1720  int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1721  s->intra_matrix[j]= last;
1722  s->chroma_intra_matrix[j]= last;
1723  }
1724  }
1725 
1726  /* load custom non intra matrix */
1727  if(get_bits1(gb)){
1728  int last=0;
1729  for(i=0; i<64; i++){
1730  int j;
1731  v= get_bits(gb, 8);
1732  if(v==0) break;
1733 
1734  last= v;
1735  j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1736  s->inter_matrix[j]= v;
1737  s->chroma_inter_matrix[j]= v;
1738  }
1739 
1740  /* replicate last value */
1741  for(; i<64; i++){
1742  int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1743  s->inter_matrix[j]= last;
1744  s->chroma_inter_matrix[j]= last;
1745  }
1746  }
1747 
1748  // FIXME a bunch of grayscale shape things
1749  }
1750 
1751  if(vo_ver_id != 1)
1752  s->quarter_sample= get_bits1(gb);
1753  else s->quarter_sample=0;
1754 
1755  if(!get_bits1(gb)){
1756  int pos= get_bits_count(gb);
1757  int estimation_method= get_bits(gb, 2);
1758  if(estimation_method<2){
1759  if(!get_bits1(gb)){
1760  s->cplx_estimation_trash_i += 8*get_bits1(gb); //opaque
1761  s->cplx_estimation_trash_i += 8*get_bits1(gb); //transparent
1762  s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_cae
1763  s->cplx_estimation_trash_i += 8*get_bits1(gb); //inter_cae
1764  s->cplx_estimation_trash_i += 8*get_bits1(gb); //no_update
1765  s->cplx_estimation_trash_i += 8*get_bits1(gb); //upampling
1766  }
1767  if(!get_bits1(gb)){
1768  s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_blocks
1769  s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter_blocks
1770  s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter4v_blocks
1771  s->cplx_estimation_trash_i += 8*get_bits1(gb); //not coded blocks
1772  }
1773  if(!check_marker(gb, "in complexity estimation part 1")){
1774  skip_bits_long(gb, pos - get_bits_count(gb));
1775  goto no_cplx_est;
1776  }
1777  if(!get_bits1(gb)){
1778  s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_coeffs
1779  s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_lines
1780  s->cplx_estimation_trash_i += 8*get_bits1(gb); //vlc_syms
1781  s->cplx_estimation_trash_i += 4*get_bits1(gb); //vlc_bits
1782  }
1783  if(!get_bits1(gb)){
1784  s->cplx_estimation_trash_p += 8*get_bits1(gb); //apm
1785  s->cplx_estimation_trash_p += 8*get_bits1(gb); //npm
1786  s->cplx_estimation_trash_b += 8*get_bits1(gb); //interpolate_mc_q
1787  s->cplx_estimation_trash_p += 8*get_bits1(gb); //forwback_mc_q
1788  s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel2
1789  s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel4
1790  }
1791  if(!check_marker(gb, "in complexity estimation part 2")){
1792  skip_bits_long(gb, pos - get_bits_count(gb));
1793  goto no_cplx_est;
1794  }
1795  if(estimation_method==1){
1796  s->cplx_estimation_trash_i += 8*get_bits1(gb); //sadct
1797  s->cplx_estimation_trash_p += 8*get_bits1(gb); //qpel
1798  }
1799  }else
1800  av_log(s->avctx, AV_LOG_ERROR, "Invalid Complexity estimation method %d\n", estimation_method);
1801  }else{
1802 no_cplx_est:
1803  s->cplx_estimation_trash_i=
1804  s->cplx_estimation_trash_p=
1805  s->cplx_estimation_trash_b= 0;
1806  }
1807 
1808  s->resync_marker= !get_bits1(gb); /* resync_marker_disabled */
1809 
1810  s->data_partitioning= get_bits1(gb);
1811  if(s->data_partitioning){
1812  s->rvlc= get_bits1(gb);
1813  }
1814 
1815  if(vo_ver_id != 1) {
1816  s->new_pred= get_bits1(gb);
1817  if(s->new_pred){
1818  av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
1819  skip_bits(gb, 2); /* requested upstream message type */
1820  skip_bits1(gb); /* newpred segment type */
1821  }
1822  s->reduced_res_vop= get_bits1(gb);
1823  if(s->reduced_res_vop) av_log(s->avctx, AV_LOG_ERROR, "reduced resolution VOP not supported\n");
1824  }
1825  else{
1826  s->new_pred=0;
1827  s->reduced_res_vop= 0;
1828  }
1829 
1830  s->scalability= get_bits1(gb);
1831 
1832  if (s->scalability) {
1833  GetBitContext bak= *gb;
1834  int h_sampling_factor_n;
1835  int h_sampling_factor_m;
1836  int v_sampling_factor_n;
1837  int v_sampling_factor_m;
1838 
1839  s->hierachy_type= get_bits1(gb);
1840  skip_bits(gb, 4); /* ref_layer_id */
1841  skip_bits1(gb); /* ref_layer_sampling_dir */
1842  h_sampling_factor_n= get_bits(gb, 5);
1843  h_sampling_factor_m= get_bits(gb, 5);
1844  v_sampling_factor_n= get_bits(gb, 5);
1845  v_sampling_factor_m= get_bits(gb, 5);
1846  s->enhancement_type= get_bits1(gb);
1847 
1848  if( h_sampling_factor_n==0 || h_sampling_factor_m==0
1849  || v_sampling_factor_n==0 || v_sampling_factor_m==0){
1850  /* illegal scalability header (VERY broken encoder),
1851  * trying to workaround */
1852  s->scalability=0;
1853  *gb= bak;
1854  }else
1855  av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
1856 
1857  // bin shape stuff FIXME
1858  }
1859  }
1860 
1861  if(s->avctx->debug&FF_DEBUG_PICT_INFO) {
1862  av_log(s->avctx, AV_LOG_DEBUG, "tb %d/%d, tincrbits:%d, qp_prec:%d, ps:%d, %s%s%s%s\n",
1863  s->avctx->time_base.num, s->avctx->time_base.den,
1864  s->time_increment_bits,
1865  s->quant_precision,
1866  s->progressive_sequence,
1867  s->scalability ? "scalability " :"" , s->quarter_sample ? "qpel " : "",
1868  s->data_partitioning ? "partition " : "", s->rvlc ? "rvlc " : ""
1869  );
1870  }
1871 
1872  return 0;
1873 }
1874 
1875 /**
1876  * Decode the user data stuff in the header.
1877  * Also initializes divx/xvid/lavc_version/build.
1878  */
1879 static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
1880  char buf[256];
1881  int i;
1882  int e;
1883  int ver = 0, build = 0, ver2 = 0, ver3 = 0;
1884  char last;
1885 
1886  for(i=0; i<255 && get_bits_count(gb) < gb->size_in_bits; i++){
1887  if(show_bits(gb, 23) == 0) break;
1888  buf[i]= get_bits(gb, 8);
1889  }
1890  buf[i]=0;
1891 
1892  /* divx detection */
1893  e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
1894  if(e<2)
1895  e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
1896  if(e>=2){
1897  s->divx_version= ver;
1898  s->divx_build= build;
1899  s->divx_packed= e==3 && last=='p';
1900  if(s->divx_packed && !s->showed_packed_warning) {
1901  av_log(s->avctx, AV_LOG_WARNING, "Invalid and inefficient vfw-avi packed B frames detected\n");
1902  s->showed_packed_warning=1;
1903  }
1904  }
1905 
1906  /* libavcodec detection */
1907  e=sscanf(buf, "FFmpe%*[^b]b%d", &build)+3;
1908  if(e!=4)
1909  e=sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
1910  if(e!=4){
1911  e=sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3)+1;
1912  if (e>1)
1913  build= (ver<<16) + (ver2<<8) + ver3;
1914  }
1915  if(e!=4){
1916  if(strcmp(buf, "ffmpeg")==0){
1917  s->lavc_build= 4600;
1918  }
1919  }
1920  if(e==4){
1921  s->lavc_build= build;
1922  }
1923 
1924  /* Xvid detection */
1925  e=sscanf(buf, "XviD%d", &build);
1926  if(e==1){
1927  s->xvid_build= build;
1928  }
1929 
1930  return 0;
1931 }
1932 
1933 static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
1934  int time_incr, time_increment;
1935 
1936  s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I; /* pict type: I = 0 , P = 1 */
1937  if(s->pict_type==AV_PICTURE_TYPE_B && s->low_delay && s->vol_control_parameters==0 && !(s->flags & CODEC_FLAG_LOW_DELAY)){
1938  av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
1939  s->low_delay=0;
1940  }
1941 
1942  s->partitioned_frame= s->data_partitioning && s->pict_type!=AV_PICTURE_TYPE_B;
1943  if(s->partitioned_frame)
1944  s->decode_mb= mpeg4_decode_partitioned_mb;
1945  else
1946  s->decode_mb= mpeg4_decode_mb;
1947 
1948  time_incr=0;
1949  while (get_bits1(gb) != 0)
1950  time_incr++;
1951 
1952  check_marker(gb, "before time_increment");
1953 
1954  if(s->time_increment_bits==0 || !(show_bits(gb, s->time_increment_bits+1)&1)){
1955  av_log(s->avctx, AV_LOG_ERROR, "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
1956 
1957  for(s->time_increment_bits=1 ;s->time_increment_bits<16; s->time_increment_bits++){
1958  if ( s->pict_type == AV_PICTURE_TYPE_P
1959  || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE)) {
1960  if((show_bits(gb, s->time_increment_bits+6)&0x37) == 0x30) break;
1961  }else
1962  if((show_bits(gb, s->time_increment_bits+5)&0x1F) == 0x18) break;
1963  }
1964 
1965  av_log(s->avctx, AV_LOG_ERROR, "my guess is %d bits ;)\n",s->time_increment_bits);
1966  if (s->avctx->time_base.den && 4*s->avctx->time_base.den < 1<<s->time_increment_bits) {
1967  s->avctx->time_base.den = 1<<s->time_increment_bits;
1968  }
1969  }
1970 
1971  if(IS_3IV1) time_increment= get_bits1(gb); //FIXME investigate further
1972  else time_increment= get_bits(gb, s->time_increment_bits);
1973 
1974  if(s->pict_type!=AV_PICTURE_TYPE_B){
1975  s->last_time_base= s->time_base;
1976  s->time_base+= time_incr;
1977  s->time= s->time_base*s->avctx->time_base.den + time_increment;
1978  if(s->workaround_bugs&FF_BUG_UMP4){
1979  if(s->time < s->last_non_b_time){
1980  /* header is not mpeg-4-compatible, broken encoder,
1981  * trying to workaround */
1982  s->time_base++;
1983  s->time+= s->avctx->time_base.den;
1984  }
1985  }
1986  s->pp_time= s->time - s->last_non_b_time;
1987  s->last_non_b_time= s->time;
1988  }else{
1989  s->time= (s->last_time_base + time_incr)*s->avctx->time_base.den + time_increment;
1990  s->pb_time= s->pp_time - (s->last_non_b_time - s->time);
1991  if(s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time<=0){
1992  /* messed up order, maybe after seeking? skipping current b-frame */
1993  return FRAME_SKIPPED;
1994  }
1995  ff_mpeg4_init_direct_mv(s);
1996 
1997  if(s->t_frame==0) s->t_frame= s->pb_time;
1998  if(s->t_frame==0) s->t_frame=1; // 1/0 protection
1999  s->pp_field_time= ( ROUNDED_DIV(s->last_non_b_time, s->t_frame)
2000  - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
2001  s->pb_field_time= ( ROUNDED_DIV(s->time, s->t_frame)
2002  - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
2003  if(!s->progressive_sequence){
2004  if(s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1)
2005  return FRAME_SKIPPED;
2006  }
2007  }
2008 
2009  if(s->avctx->time_base.num)
2010  s->current_picture_ptr->f.pts = ROUNDED_DIV(s->time, s->avctx->time_base.num);
2011  else
2012  s->current_picture_ptr->f.pts = AV_NOPTS_VALUE;
2013  if(s->avctx->debug&FF_DEBUG_PTS)
2014  av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n",
2015  s->current_picture_ptr->f.pts);
2016 
2017  check_marker(gb, "before vop_coded");
2018 
2019  /* vop coded */
2020  if (get_bits1(gb) != 1){
2021  if(s->avctx->debug&FF_DEBUG_PICT_INFO)
2022  av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
2023  return FRAME_SKIPPED;
2024  }
2025  if (s->shape != BIN_ONLY_SHAPE && ( s->pict_type == AV_PICTURE_TYPE_P
2026  || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE))) {
2027  /* rounding type for motion estimation */
2028  s->no_rounding = get_bits1(gb);
2029  } else {
2030  s->no_rounding = 0;
2031  }
2032 //FIXME reduced res stuff
2033 
2034  if (s->shape != RECT_SHAPE) {
2035  if (s->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
2036  skip_bits(gb, 13); /* width */
2037  skip_bits1(gb); /* marker */
2038  skip_bits(gb, 13); /* height */
2039  skip_bits1(gb); /* marker */
2040  skip_bits(gb, 13); /* hor_spat_ref */
2041  skip_bits1(gb); /* marker */
2042  skip_bits(gb, 13); /* ver_spat_ref */
2043  }
2044  skip_bits1(gb); /* change_CR_disable */
2045 
2046  if (get_bits1(gb) != 0) {
2047  skip_bits(gb, 8); /* constant_alpha_value */
2048  }
2049  }
2050 //FIXME complexity estimation stuff
2051 
2052  if (s->shape != BIN_ONLY_SHAPE) {
2053  skip_bits_long(gb, s->cplx_estimation_trash_i);
2054  if(s->pict_type != AV_PICTURE_TYPE_I)
2055  skip_bits_long(gb, s->cplx_estimation_trash_p);
2056  if(s->pict_type == AV_PICTURE_TYPE_B)
2057  skip_bits_long(gb, s->cplx_estimation_trash_b);
2058 
2059  if(get_bits_left(gb) < 3) {
2060  av_log(s->avctx, AV_LOG_ERROR, "Header truncated\n");
2061  return -1;
2062  }
2063  s->intra_dc_threshold= ff_mpeg4_dc_threshold[ get_bits(gb, 3) ];
2064  if(!s->progressive_sequence){
2065  s->top_field_first= get_bits1(gb);
2066  s->alternate_scan= get_bits1(gb);
2067  }else
2068  s->alternate_scan= 0;
2069  }
2070 
2071  if(s->alternate_scan){
2072  ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable , ff_alternate_vertical_scan);
2073  ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable , ff_alternate_vertical_scan);
2074  ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
2075  ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
2076  } else{
2077  ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable , ff_zigzag_direct);
2078  ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable , ff_zigzag_direct);
2079  ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
2080  ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
2081  }
2082 
2083  if(s->pict_type == AV_PICTURE_TYPE_S && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
2084  if(mpeg4_decode_sprite_trajectory(s, gb) < 0)
2085  return -1;
2086  if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
2087  if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
2088  }
2089 
2090  if (s->shape != BIN_ONLY_SHAPE) {
2091  s->chroma_qscale= s->qscale = get_bits(gb, s->quant_precision);
2092  if(s->qscale==0){
2093  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (qscale=0)\n");
2094  return -1; // makes no sense to continue, as there is nothing left from the image then
2095  }
2096 
2097  if (s->pict_type != AV_PICTURE_TYPE_I) {
2098  s->f_code = get_bits(gb, 3); /* fcode_for */
2099  if(s->f_code==0){
2100  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (f_code=0)\n");
2101  s->f_code=1;
2102  return -1; // makes no sense to continue, as the MV decoding will break very quickly
2103  }
2104  }else
2105  s->f_code=1;
2106 
2107  if (s->pict_type == AV_PICTURE_TYPE_B) {
2108  s->b_code = get_bits(gb, 3);
2109  if(s->b_code==0){
2110  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (b_code=0)\n");
2111  s->b_code=1;
2112  return -1; // makes no sense to continue, as the MV decoding will break very quickly
2113  }
2114  }else
2115  s->b_code=1;
2116 
2117  if(s->avctx->debug&FF_DEBUG_PICT_INFO){
2118  av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
2119  s->qscale, s->f_code, s->b_code,
2120  s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
2121  gb->size_in_bits,s->progressive_sequence, s->alternate_scan, s->top_field_first,
2122  s->quarter_sample ? "q" : "h", s->data_partitioning, s->resync_marker, s->num_sprite_warping_points,
2123  s->sprite_warping_accuracy, 1-s->no_rounding, s->vo_type, s->vol_control_parameters ? " VOLC" : " ", s->intra_dc_threshold,
2124  s->cplx_estimation_trash_i, s->cplx_estimation_trash_p, s->cplx_estimation_trash_b,
2125  s->time,
2126  time_increment
2127  );
2128  }
2129 
2130  if(!s->scalability){
2131  if (s->shape!=RECT_SHAPE && s->pict_type!=AV_PICTURE_TYPE_I) {
2132  skip_bits1(gb); // vop shape coding type
2133  }
2134  }else{
2135  if(s->enhancement_type){
2136  int load_backward_shape= get_bits1(gb);
2137  if(load_backward_shape){
2138  av_log(s->avctx, AV_LOG_ERROR, "load backward shape isn't supported\n");
2139  }
2140  }
2141  skip_bits(gb, 2); //ref_select_code
2142  }
2143  }
2144  /* detect buggy encoders which don't set the low_delay flag (divx4/xvid/opendivx)*/
2145  // note we cannot detect divx5 without b-frames easily (although it's buggy too)
2146  if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==-1 && s->picture_number==0){
2147  av_log(s->avctx, AV_LOG_WARNING, "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
2148  s->low_delay=1;
2149  }
2150 
2151  s->picture_number++; // better than pic number==0 always ;)
2152 
2153  s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support
2154  s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
2155 
2156  if(s->workaround_bugs&FF_BUG_EDGE){
2157  s->h_edge_pos= s->width;
2158  s->v_edge_pos= s->height;
2159  }
2160  return 0;
2161 }
2162 
2163 /**
2164  * Decode mpeg4 headers.
2165  * @return <0 if no VOP found (or a damaged one)
2166  * FRAME_SKIPPED if a not coded VOP is found
2167  * 0 if a VOP is found
2168  */
2169 int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb)
2170 {
2171  unsigned startcode, v;
2172 
2173  /* search next start code */
2174  align_get_bits(gb);
2175 
2176  if(s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630){
2177  skip_bits(gb, 24);
2178  if(get_bits(gb, 8) == 0xF0)
2179  goto end;
2180  }
2181 
2182  startcode = 0xff;
2183  for(;;) {
2184  if(get_bits_count(gb) >= gb->size_in_bits){
2185  if(gb->size_in_bits==8 && (s->divx_version>=0 || s->xvid_build>=0) || s->codec_tag == AV_RL32("QMP4")){
2186  av_log(s->avctx, AV_LOG_VERBOSE, "frame skip %d\n", gb->size_in_bits);
2187  return FRAME_SKIPPED; //divx bug
2188  }else
2189  return -1; //end of stream
2190  }
2191 
2192  /* use the bits after the test */
2193  v = get_bits(gb, 8);
2194  startcode = ((startcode << 8) | v) & 0xffffffff;
2195 
2196  if((startcode&0xFFFFFF00) != 0x100)
2197  continue; //no startcode
2198 
2199  if(s->avctx->debug&FF_DEBUG_STARTCODE){
2200  av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
2201  if (startcode<=0x11F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
2202  else if(startcode<=0x12F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
2203  else if(startcode<=0x13F) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2204  else if(startcode<=0x15F) av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
2205  else if(startcode<=0x1AF) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2206  else if(startcode==0x1B0) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
2207  else if(startcode==0x1B1) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
2208  else if(startcode==0x1B2) av_log(s->avctx, AV_LOG_DEBUG, "User Data");
2209  else if(startcode==0x1B3) av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
2210  else if(startcode==0x1B4) av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
2211  else if(startcode==0x1B5) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
2212  else if(startcode==0x1B6) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
2213  else if(startcode==0x1B7) av_log(s->avctx, AV_LOG_DEBUG, "slice start");
2214  else if(startcode==0x1B8) av_log(s->avctx, AV_LOG_DEBUG, "extension start");
2215  else if(startcode==0x1B9) av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
2216  else if(startcode==0x1BA) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
2217  else if(startcode==0x1BB) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
2218  else if(startcode==0x1BC) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
2219  else if(startcode==0x1BD) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
2220  else if(startcode==0x1BE) av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
2221  else if(startcode==0x1BF) av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
2222  else if(startcode==0x1C0) av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
2223  else if(startcode==0x1C1) av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
2224  else if(startcode==0x1C2) av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
2225  else if(startcode==0x1C3) av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
2226  else if(startcode<=0x1C5) av_log(s->avctx, AV_LOG_DEBUG, "reserved");
2227  else if(startcode<=0x1FF) av_log(s->avctx, AV_LOG_DEBUG, "System start");
2228  av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
2229  }
2230 
2231  if(startcode >= 0x120 && startcode <= 0x12F){
2232  if(decode_vol_header(s, gb) < 0)
2233  return -1;
2234  }
2235  else if(startcode == USER_DATA_STARTCODE){
2236  decode_user_data(s, gb);
2237  }
2238  else if(startcode == GOP_STARTCODE){
2239  mpeg4_decode_gop_header(s, gb);
2240  }
2241  else if(startcode == VOS_STARTCODE){
2242  mpeg4_decode_profile_level(s, gb);
2243  }
2244  else if(startcode == VOP_STARTCODE){
2245  break;
2246  }
2247 
2248  align_get_bits(gb);
2249  startcode = 0xff;
2250  }
2251 end:
2252  if(s->flags& CODEC_FLAG_LOW_DELAY)
2253  s->low_delay=1;
2254  s->avctx->has_b_frames= !s->low_delay;
2255  return decode_vop_header(s, gb);
2256 }
2257 
2258 av_cold void ff_mpeg4videodec_static_init(void) {
2259  static int done = 0;
2260 
2261  if (!done) {
2262  ff_init_rl(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);
2263  ff_init_rl(&ff_rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
2264  ff_init_rl(&ff_rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
2265  INIT_VLC_RL(ff_mpeg4_rl_intra, 554);
2266  INIT_VLC_RL(ff_rvlc_rl_inter, 1072);
2267  INIT_VLC_RL(ff_rvlc_rl_intra, 1072);
2268  INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
2269  &ff_mpeg4_DCtab_lum[0][1], 2, 1,
2270  &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
2271  INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
2272  &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
2273  &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
2274  INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
2275  &ff_sprite_trajectory_tab[0][1], 4, 2,
2276  &ff_sprite_trajectory_tab[0][0], 4, 2, 128);
2277  INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
2278  &ff_mb_type_b_tab[0][1], 2, 1,
2279  &ff_mb_type_b_tab[0][0], 2, 1, 16);
2280  done = 1;
2281  }
2282 }
2283 
2284 static av_cold int decode_init(AVCodecContext *avctx)
2285 {
2286  MpegEncContext *s = avctx->priv_data;
2287  int ret;
2288 
2289  s->divx_version=
2290  s->divx_build=
2291  s->xvid_build=
2292  s->lavc_build= -1;
2293 
2294  if((ret=ff_h263_decode_init(avctx)) < 0)
2295  return ret;
2296 
2297  ff_mpeg4videodec_static_init();
2298 
2299  s->h263_pred = 1;
2300  s->low_delay = 0; //default, might be overridden in the vol header during header parsing
2301  s->decode_mb= mpeg4_decode_mb;
2302  s->time_increment_bits = 4; /* default value for broken headers */
2303  avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
2304 
2305  return 0;
2306 }
2307 
2308 static const AVProfile mpeg4_video_profiles[] = {
2309  { FF_PROFILE_MPEG4_SIMPLE, "Simple Profile" },
2310  { FF_PROFILE_MPEG4_SIMPLE_SCALABLE, "Simple Scalable Profile" },
2311  { FF_PROFILE_MPEG4_CORE, "Core Profile" },
2312  { FF_PROFILE_MPEG4_MAIN, "Main Profile" },
2313  { FF_PROFILE_MPEG4_N_BIT, "N-bit Profile" },
2314  { FF_PROFILE_MPEG4_SCALABLE_TEXTURE, "Scalable Texture Profile" },
2315  { FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION, "Simple Face Animation Profile" },
2316  { FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE, "Basic Animated Texture Profile" },
2317  { FF_PROFILE_MPEG4_HYBRID, "Hybrid Profile" },
2318  { FF_PROFILE_MPEG4_ADVANCED_REAL_TIME, "Advanced Real Time Simple Profile" },
2319  { FF_PROFILE_MPEG4_CORE_SCALABLE, "Code Scalable Profile" },
2320  { FF_PROFILE_MPEG4_ADVANCED_CODING, "Advanced Coding Profile" },
2321  { FF_PROFILE_MPEG4_ADVANCED_CORE, "Advanced Core Profile" },
2322  { FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE, "Advanced Scalable Texture Profile" },
2323  { FF_PROFILE_MPEG4_SIMPLE_STUDIO, "Simple Studio Profile" },
2324  { FF_PROFILE_MPEG4_ADVANCED_SIMPLE, "Advanced Simple Profile" },
2325  { FF_PROFILE_UNKNOWN },
2326 };
2327 
2328 static const AVOption mpeg4_options[] = {
2329  {"quarter_sample", "1/4 subpel MC", offsetof(MpegEncContext, quarter_sample), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
2330  {"divx_packed", "divx style packed b frames", offsetof(MpegEncContext, divx_packed), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
2331  {NULL}
2332 };
2333 
2334 static const AVClass mpeg4_class = {
2335  "MPEG4 Video Decoder",
2336  av_default_item_name,
2337  mpeg4_options,
2338  LIBAVUTIL_VERSION_INT,
2339 };
2340 
2341 static const AVClass mpeg4_vdpau_class = {
2342  "MPEG4 Video VDPAU Decoder",
2343  av_default_item_name,
2344  mpeg4_options,
2345  LIBAVUTIL_VERSION_INT,
2346 };
2347 
2348 AVCodec ff_mpeg4_decoder = {
2349  .name = "mpeg4",
2350  .type = AVMEDIA_TYPE_VIDEO,
2351  .id = AV_CODEC_ID_MPEG4,
2352  .priv_data_size = sizeof(MpegEncContext),
2353  .init = decode_init,
2354  .close = ff_h263_decode_end,
2355  .decode = ff_h263_decode_frame,
2356  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2357  CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2358  CODEC_CAP_FRAME_THREADS,
2359  .flush = ff_mpeg_flush,
2360  .max_lowres = 3,
2361  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
2362  .pix_fmts = ff_h263_hwaccel_pixfmt_list_420,
2363  .profiles = NULL_IF_CONFIG_SMALL(mpeg4_video_profiles),
2364  .update_thread_context = ONLY_IF_THREADS_ENABLED(ff_mpeg_update_thread_context),
2365  .priv_class = &mpeg4_class,
2366 };
2367 
2368 
2369 #if CONFIG_MPEG4_VDPAU_DECODER
2370 AVCodec ff_mpeg4_vdpau_decoder = {
2371  .name = "mpeg4_vdpau",
2372  .type = AVMEDIA_TYPE_VIDEO,
2373  .id = AV_CODEC_ID_MPEG4,
2374  .priv_data_size = sizeof(MpegEncContext),
2375  .init = decode_init,
2376  .close = ff_h263_decode_end,
2377  .decode = ff_h263_decode_frame,
2378  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2379  CODEC_CAP_HWACCEL_VDPAU,
2380  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
2381  .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_VDPAU_MPEG4,
2382  AV_PIX_FMT_NONE },
2383  .priv_class = &mpeg4_vdpau_class,
2384 };
2385 #endif
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