doxygen: misc consistency, spelling and wording fixes
[ffmpeg.git] / libavcodec / mpeg4videodec.c
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 Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22
23 #include "mpegvideo.h"
24 #include "mpeg4video.h"
25 #include "h263.h"
26 #include "thread.h"
27
28 // The defines below define the number of bits that are read at once for
29 // reading vlc values. Changing these may improve speed and data cache needs
30 // be aware though that decreasing them may need the number of stages that is
31 // passed to get_vlc* to be increased.
32 #define SPRITE_TRAJ_VLC_BITS 6
33 #define DC_VLC_BITS 9
34 #define MB_TYPE_B_VLC_BITS 4
35
36
37 static VLC dc_lum, dc_chrom;
38 static VLC sprite_trajectory;
39 static VLC mb_type_b_vlc;
40
41 static const int mb_type_b_map[4]= {
42     MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
43     MB_TYPE_L0L1 | MB_TYPE_16x16,
44     MB_TYPE_L1 | MB_TYPE_16x16,
45     MB_TYPE_L0 | MB_TYPE_16x16,
46 };
47
48 /**
49  * Predict the ac.
50  * @param n block index (0-3 are luma, 4-5 are chroma)
51  * @param dir the ac prediction direction
52  */
53 void mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
54                    int dir)
55 {
56     int i;
57     int16_t *ac_val, *ac_val1;
58     int8_t * const qscale_table = s->current_picture.f.qscale_table;
59
60     /* find prediction */
61     ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
62     ac_val1 = ac_val;
63     if (s->ac_pred) {
64         if (dir == 0) {
65             const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
66             /* left prediction */
67             ac_val -= 16;
68
69             if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
70                 /* same qscale */
71                 for(i=1;i<8;i++) {
72                     block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
73                 }
74             }else{
75                 /* different qscale, we must rescale */
76                 for(i=1;i<8;i++) {
77                     block[s->dsp.idct_permutation[i<<3]] += ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
78                 }
79             }
80         } else {
81             const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
82             /* top prediction */
83             ac_val -= 16 * s->block_wrap[n];
84
85             if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
86                 /* same qscale */
87                 for(i=1;i<8;i++) {
88                     block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
89                 }
90             }else{
91                 /* different qscale, we must rescale */
92                 for(i=1;i<8;i++) {
93                     block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
94                 }
95             }
96         }
97     }
98     /* left copy */
99     for(i=1;i<8;i++)
100         ac_val1[i    ] = block[s->dsp.idct_permutation[i<<3]];
101
102     /* top copy */
103     for(i=1;i<8;i++)
104         ac_val1[8 + i] = block[s->dsp.idct_permutation[i   ]];
105
106 }
107
108 /**
109  * check if the next stuff is a resync marker or the end.
110  * @return 0 if not
111  */
112 static inline int mpeg4_is_resync(MpegEncContext *s){
113     int bits_count= get_bits_count(&s->gb);
114     int v= show_bits(&s->gb, 16);
115
116     if(s->workaround_bugs&FF_BUG_NO_PADDING){
117         return 0;
118     }
119
120     while(v<=0xFF){
121         if(s->pict_type==AV_PICTURE_TYPE_B || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
122             break;
123         skip_bits(&s->gb, 8+s->pict_type);
124         bits_count+= 8+s->pict_type;
125         v= show_bits(&s->gb, 16);
126     }
127
128     if(bits_count + 8 >= s->gb.size_in_bits){
129         v>>=8;
130         v|= 0x7F >> (7-(bits_count&7));
131
132         if(v==0x7F)
133             return 1;
134     }else{
135         if(v == ff_mpeg4_resync_prefix[bits_count&7]){
136             int len;
137             GetBitContext gb= s->gb;
138
139             skip_bits(&s->gb, 1);
140             align_get_bits(&s->gb);
141
142             for(len=0; len<32; len++){
143                 if(get_bits1(&s->gb)) break;
144             }
145
146             s->gb= gb;
147
148             if(len>=ff_mpeg4_get_video_packet_prefix_length(s))
149                 return 1;
150         }
151     }
152     return 0;
153 }
154
155 static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
156 {
157     int i;
158     int a= 2<<s->sprite_warping_accuracy;
159     int rho= 3-s->sprite_warping_accuracy;
160     int r=16/a;
161     const int vop_ref[4][2]= {{0,0}, {s->width,0}, {0, s->height}, {s->width, s->height}}; // only true for rectangle shapes
162     int d[4][2]={{0,0}, {0,0}, {0,0}, {0,0}};
163     int sprite_ref[4][2];
164     int virtual_ref[2][2];
165     int w2, h2, w3, h3;
166     int alpha=0, beta=0;
167     int w= s->width;
168     int h= s->height;
169     int min_ab;
170
171     for(i=0; i<s->num_sprite_warping_points; i++){
172         int length;
173         int x=0, y=0;
174
175         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
176         if(length){
177             x= get_xbits(gb, length);
178         }
179         if(!(s->divx_version==500 && s->divx_build==413)) skip_bits1(gb); /* marker bit */
180
181         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
182         if(length){
183             y=get_xbits(gb, length);
184         }
185         skip_bits1(gb); /* marker bit */
186         s->sprite_traj[i][0]= d[i][0]= x;
187         s->sprite_traj[i][1]= d[i][1]= y;
188     }
189     for(; i<4; i++)
190         s->sprite_traj[i][0]= s->sprite_traj[i][1]= 0;
191
192     while((1<<alpha)<w) alpha++;
193     while((1<<beta )<h) beta++; // there seems to be a typo in the mpeg4 std for the definition of w' and h'
194     w2= 1<<alpha;
195     h2= 1<<beta;
196
197 // Note, the 4th point isn't used for GMC
198     if(s->divx_version==500 && s->divx_build==413){
199         sprite_ref[0][0]= a*vop_ref[0][0] + d[0][0];
200         sprite_ref[0][1]= a*vop_ref[0][1] + d[0][1];
201         sprite_ref[1][0]= a*vop_ref[1][0] + d[0][0] + d[1][0];
202         sprite_ref[1][1]= a*vop_ref[1][1] + d[0][1] + d[1][1];
203         sprite_ref[2][0]= a*vop_ref[2][0] + d[0][0] + d[2][0];
204         sprite_ref[2][1]= a*vop_ref[2][1] + d[0][1] + d[2][1];
205     } else {
206         sprite_ref[0][0]= (a>>1)*(2*vop_ref[0][0] + d[0][0]);
207         sprite_ref[0][1]= (a>>1)*(2*vop_ref[0][1] + d[0][1]);
208         sprite_ref[1][0]= (a>>1)*(2*vop_ref[1][0] + d[0][0] + d[1][0]);
209         sprite_ref[1][1]= (a>>1)*(2*vop_ref[1][1] + d[0][1] + d[1][1]);
210         sprite_ref[2][0]= (a>>1)*(2*vop_ref[2][0] + d[0][0] + d[2][0]);
211         sprite_ref[2][1]= (a>>1)*(2*vop_ref[2][1] + d[0][1] + d[2][1]);
212     }
213 /*    sprite_ref[3][0]= (a>>1)*(2*vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
214     sprite_ref[3][1]= (a>>1)*(2*vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
215
216 // this is mostly identical to the mpeg4 std (and is totally unreadable because of that ...)
217 // perhaps it should be reordered to be more readable ...
218 // the idea behind this virtual_ref mess is to be able to use shifts later per pixel instead of divides
219 // so the distance between points is converted from w&h based to w2&h2 based which are of the 2^x form
220     virtual_ref[0][0]= 16*(vop_ref[0][0] + w2)
221         + 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);
222     virtual_ref[0][1]= 16*vop_ref[0][1]
223         + 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);
224     virtual_ref[1][0]= 16*vop_ref[0][0]
225         + 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);
226     virtual_ref[1][1]= 16*(vop_ref[0][1] + h2)
227         + 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);
228
229     switch(s->num_sprite_warping_points)
230     {
231         case 0:
232             s->sprite_offset[0][0]= 0;
233             s->sprite_offset[0][1]= 0;
234             s->sprite_offset[1][0]= 0;
235             s->sprite_offset[1][1]= 0;
236             s->sprite_delta[0][0]= a;
237             s->sprite_delta[0][1]= 0;
238             s->sprite_delta[1][0]= 0;
239             s->sprite_delta[1][1]= a;
240             s->sprite_shift[0]= 0;
241             s->sprite_shift[1]= 0;
242             break;
243         case 1: //GMC only
244             s->sprite_offset[0][0]= sprite_ref[0][0] - a*vop_ref[0][0];
245             s->sprite_offset[0][1]= sprite_ref[0][1] - a*vop_ref[0][1];
246             s->sprite_offset[1][0]= ((sprite_ref[0][0]>>1)|(sprite_ref[0][0]&1)) - a*(vop_ref[0][0]/2);
247             s->sprite_offset[1][1]= ((sprite_ref[0][1]>>1)|(sprite_ref[0][1]&1)) - a*(vop_ref[0][1]/2);
248             s->sprite_delta[0][0]= a;
249             s->sprite_delta[0][1]= 0;
250             s->sprite_delta[1][0]= 0;
251             s->sprite_delta[1][1]= a;
252             s->sprite_shift[0]= 0;
253             s->sprite_shift[1]= 0;
254             break;
255         case 2:
256             s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+rho))
257                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][0])
258                                                   + ( r*sprite_ref[0][1] - virtual_ref[0][1])*(-vop_ref[0][1])
259                                                   + (1<<(alpha+rho-1));
260             s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+rho))
261                                                   + (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-vop_ref[0][0])
262                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][1])
263                                                   + (1<<(alpha+rho-1));
264             s->sprite_offset[1][0]= ( (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][0] + 1)
265                                      +( r*sprite_ref[0][1] - virtual_ref[0][1])*(-2*vop_ref[0][1] + 1)
266                                      +2*w2*r*sprite_ref[0][0]
267                                      - 16*w2
268                                      + (1<<(alpha+rho+1)));
269             s->sprite_offset[1][1]= ( (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-2*vop_ref[0][0] + 1)
270                                      +(-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][1] + 1)
271                                      +2*w2*r*sprite_ref[0][1]
272                                      - 16*w2
273                                      + (1<<(alpha+rho+1)));
274             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
275             s->sprite_delta[0][1]=   (+r*sprite_ref[0][1] - virtual_ref[0][1]);
276             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1]);
277             s->sprite_delta[1][1]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
278
279             s->sprite_shift[0]= alpha+rho;
280             s->sprite_shift[1]= alpha+rho+2;
281             break;
282         case 3:
283             min_ab= FFMIN(alpha, beta);
284             w3= w2>>min_ab;
285             h3= h2>>min_ab;
286             s->sprite_offset[0][0]=  (sprite_ref[0][0]<<(alpha+beta+rho-min_ab))
287                                    + (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-vop_ref[0][0])
288                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-vop_ref[0][1])
289                                    + (1<<(alpha+beta+rho-min_ab-1));
290             s->sprite_offset[0][1]=  (sprite_ref[0][1]<<(alpha+beta+rho-min_ab))
291                                    + (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-vop_ref[0][0])
292                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-vop_ref[0][1])
293                                    + (1<<(alpha+beta+rho-min_ab-1));
294             s->sprite_offset[1][0]=  (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-2*vop_ref[0][0] + 1)
295                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-2*vop_ref[0][1] + 1)
296                                    + 2*w2*h3*r*sprite_ref[0][0]
297                                    - 16*w2*h3
298                                    + (1<<(alpha+beta+rho-min_ab+1));
299             s->sprite_offset[1][1]=  (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-2*vop_ref[0][0] + 1)
300                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-2*vop_ref[0][1] + 1)
301                                    + 2*w2*h3*r*sprite_ref[0][1]
302                                    - 16*w2*h3
303                                    + (1<<(alpha+beta+rho-min_ab+1));
304             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3;
305             s->sprite_delta[0][1]=   (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3;
306             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3;
307             s->sprite_delta[1][1]=   (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3;
308
309             s->sprite_shift[0]= alpha + beta + rho - min_ab;
310             s->sprite_shift[1]= alpha + beta + rho - min_ab + 2;
311             break;
312     }
313     /* try to simplify the situation */
314     if(   s->sprite_delta[0][0] == a<<s->sprite_shift[0]
315        && s->sprite_delta[0][1] == 0
316        && s->sprite_delta[1][0] == 0
317        && s->sprite_delta[1][1] == a<<s->sprite_shift[0])
318     {
319         s->sprite_offset[0][0]>>=s->sprite_shift[0];
320         s->sprite_offset[0][1]>>=s->sprite_shift[0];
321         s->sprite_offset[1][0]>>=s->sprite_shift[1];
322         s->sprite_offset[1][1]>>=s->sprite_shift[1];
323         s->sprite_delta[0][0]= a;
324         s->sprite_delta[0][1]= 0;
325         s->sprite_delta[1][0]= 0;
326         s->sprite_delta[1][1]= a;
327         s->sprite_shift[0]= 0;
328         s->sprite_shift[1]= 0;
329         s->real_sprite_warping_points=1;
330     }
331     else{
332         int shift_y= 16 - s->sprite_shift[0];
333         int shift_c= 16 - s->sprite_shift[1];
334         for(i=0; i<2; i++){
335             s->sprite_offset[0][i]<<= shift_y;
336             s->sprite_offset[1][i]<<= shift_c;
337             s->sprite_delta[0][i]<<= shift_y;
338             s->sprite_delta[1][i]<<= shift_y;
339             s->sprite_shift[i]= 16;
340         }
341         s->real_sprite_warping_points= s->num_sprite_warping_points;
342     }
343 }
344
345 /**
346  * Decode the next video packet.
347  * @return <0 if something went wrong
348  */
349 int mpeg4_decode_video_packet_header(MpegEncContext *s)
350 {
351     int mb_num_bits= av_log2(s->mb_num - 1) + 1;
352     int header_extension=0, mb_num, len;
353
354     /* is there enough space left for a video packet + header */
355     if( get_bits_count(&s->gb) > s->gb.size_in_bits-20) return -1;
356
357     for(len=0; len<32; len++){
358         if(get_bits1(&s->gb)) break;
359     }
360
361     if(len!=ff_mpeg4_get_video_packet_prefix_length(s)){
362         av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
363         return -1;
364     }
365
366     if(s->shape != RECT_SHAPE){
367         header_extension= get_bits1(&s->gb);
368         //FIXME more stuff here
369     }
370
371     mb_num= get_bits(&s->gb, mb_num_bits);
372     if(mb_num>=s->mb_num){
373         av_log(s->avctx, AV_LOG_ERROR, "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
374         return -1;
375     }
376     if(s->pict_type == AV_PICTURE_TYPE_B){
377         int mb_x = 0, mb_y = 0;
378
379         while (s->next_picture.f.mbskip_table[s->mb_index2xy[mb_num]]) {
380             if (!mb_x) ff_thread_await_progress((AVFrame*)s->next_picture_ptr, mb_y++, 0);
381             mb_num++;
382             if (++mb_x == s->mb_width) mb_x = 0;
383         }
384         if(mb_num >= s->mb_num) return -1; // slice contains just skipped MBs which where already decoded
385     }
386
387     s->mb_x= mb_num % s->mb_width;
388     s->mb_y= mb_num / s->mb_width;
389
390     if(s->shape != BIN_ONLY_SHAPE){
391         int qscale= get_bits(&s->gb, s->quant_precision);
392         if(qscale)
393             s->chroma_qscale=s->qscale= qscale;
394     }
395
396     if(s->shape == RECT_SHAPE){
397         header_extension= get_bits1(&s->gb);
398     }
399     if(header_extension){
400         int time_incr=0;
401
402         while (get_bits1(&s->gb) != 0)
403             time_incr++;
404
405         check_marker(&s->gb, "before time_increment in video packed header");
406         skip_bits(&s->gb, s->time_increment_bits); /* time_increment */
407         check_marker(&s->gb, "before vop_coding_type in video packed header");
408
409         skip_bits(&s->gb, 2); /* vop coding type */
410         //FIXME not rect stuff here
411
412         if(s->shape != BIN_ONLY_SHAPE){
413             skip_bits(&s->gb, 3); /* intra dc vlc threshold */
414 //FIXME don't just ignore everything
415             if(s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
416                 mpeg4_decode_sprite_trajectory(s, &s->gb);
417                 av_log(s->avctx, AV_LOG_ERROR, "untested\n");
418             }
419
420             //FIXME reduced res stuff here
421
422             if (s->pict_type != AV_PICTURE_TYPE_I) {
423                 int f_code = get_bits(&s->gb, 3);       /* fcode_for */
424                 if(f_code==0){
425                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (f_code=0)\n");
426                 }
427             }
428             if (s->pict_type == AV_PICTURE_TYPE_B) {
429                 int b_code = get_bits(&s->gb, 3);
430                 if(b_code==0){
431                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (b_code=0)\n");
432                 }
433             }
434         }
435     }
436     //FIXME new-pred stuff
437
438     return 0;
439 }
440
441 /**
442  * Get the average motion vector for a GMC MB.
443  * @param n either 0 for the x component or 1 for y
444  * @return the average MV for a GMC MB
445  */
446 static inline int get_amv(MpegEncContext *s, int n){
447     int x, y, mb_v, sum, dx, dy, shift;
448     int len = 1 << (s->f_code + 4);
449     const int a= s->sprite_warping_accuracy;
450
451     if(s->workaround_bugs & FF_BUG_AMV)
452         len >>= s->quarter_sample;
453
454     if(s->real_sprite_warping_points==1){
455         if(s->divx_version==500 && s->divx_build==413)
456             sum= s->sprite_offset[0][n] / (1<<(a - s->quarter_sample));
457         else
458             sum= RSHIFT(s->sprite_offset[0][n]<<s->quarter_sample, a);
459     }else{
460         dx= s->sprite_delta[n][0];
461         dy= s->sprite_delta[n][1];
462         shift= s->sprite_shift[0];
463         if(n) dy -= 1<<(shift + a + 1);
464         else  dx -= 1<<(shift + a + 1);
465         mb_v= s->sprite_offset[0][n] + dx*s->mb_x*16 + dy*s->mb_y*16;
466
467         sum=0;
468         for(y=0; y<16; y++){
469             int v;
470
471             v= mb_v + dy*y;
472             //XXX FIXME optimize
473             for(x=0; x<16; x++){
474                 sum+= v>>shift;
475                 v+= dx;
476             }
477         }
478         sum= RSHIFT(sum, a+8-s->quarter_sample);
479     }
480
481     if      (sum < -len) sum= -len;
482     else if (sum >= len) sum= len-1;
483
484     return sum;
485 }
486
487 /**
488  * Decode the dc value.
489  * @param n block index (0-3 are luma, 4-5 are chroma)
490  * @param dir_ptr the prediction direction will be stored here
491  * @return the quantized dc
492  */
493 static inline int mpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
494 {
495     int level, code;
496
497     if (n < 4)
498         code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
499     else
500         code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
501     if (code < 0 || code > 9 /* && s->nbit<9 */){
502         av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
503         return -1;
504     }
505     if (code == 0) {
506         level = 0;
507     } else {
508         if(IS_3IV1){
509             if(code==1)
510                 level= 2*get_bits1(&s->gb)-1;
511             else{
512                 if(get_bits1(&s->gb))
513                     level = get_bits(&s->gb, code-1) + (1<<(code-1));
514                 else
515                     level = -get_bits(&s->gb, code-1) - (1<<(code-1));
516             }
517         }else{
518             level = get_xbits(&s->gb, code);
519         }
520
521         if (code > 8){
522             if(get_bits1(&s->gb)==0){ /* marker */
523                 if(s->err_recognition&AV_EF_BITSTREAM){
524                     av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
525                     return -1;
526                 }
527             }
528         }
529     }
530
531     return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
532 }
533
534 /**
535  * Decode first partition.
536  * @return number of MBs decoded or <0 if an error occurred
537  */
538 static int mpeg4_decode_partition_a(MpegEncContext *s){
539     int mb_num;
540     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
541
542     /* decode first partition */
543     mb_num=0;
544     s->first_slice_line=1;
545     for(; s->mb_y<s->mb_height; s->mb_y++){
546         ff_init_block_index(s);
547         for(; s->mb_x<s->mb_width; s->mb_x++){
548             const int xy= s->mb_x + s->mb_y*s->mb_stride;
549             int cbpc;
550             int dir=0;
551
552             mb_num++;
553             ff_update_block_index(s);
554             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
555                 s->first_slice_line=0;
556
557             if(s->pict_type==AV_PICTURE_TYPE_I){
558                 int i;
559
560                 do{
561                     if(show_bits_long(&s->gb, 19)==DC_MARKER){
562                         return mb_num-1;
563                     }
564
565                     cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
566                     if (cbpc < 0){
567                         av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
568                         return -1;
569                     }
570                 }while(cbpc == 8);
571
572                 s->cbp_table[xy]= cbpc & 3;
573                 s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
574                 s->mb_intra = 1;
575
576                 if(cbpc & 4) {
577                     ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
578                 }
579                 s->current_picture.f.qscale_table[xy]= s->qscale;
580
581                 s->mbintra_table[xy]= 1;
582                 for(i=0; i<6; i++){
583                     int dc_pred_dir;
584                     int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
585                     if(dc < 0){
586                         av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
587                         return -1;
588                     }
589                     dir<<=1;
590                     if(dc_pred_dir) dir|=1;
591                 }
592                 s->pred_dir_table[xy]= dir;
593             }else{ /* P/S_TYPE */
594                 int mx, my, pred_x, pred_y, bits;
595                 int16_t * const mot_val = s->current_picture.f.motion_val[0][s->block_index[0]];
596                 const int stride= s->b8_stride*2;
597
598 try_again:
599                 bits= show_bits(&s->gb, 17);
600                 if(bits==MOTION_MARKER){
601                     return mb_num-1;
602                 }
603                 skip_bits1(&s->gb);
604                 if(bits&0x10000){
605                     /* skip mb */
606                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
607                         s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
608                         mx= get_amv(s, 0);
609                         my= get_amv(s, 1);
610                     }else{
611                         s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
612                         mx=my=0;
613                     }
614                     mot_val[0       ]= mot_val[2       ]=
615                     mot_val[0+stride]= mot_val[2+stride]= mx;
616                     mot_val[1       ]= mot_val[3       ]=
617                     mot_val[1+stride]= mot_val[3+stride]= my;
618
619                     if(s->mbintra_table[xy])
620                         ff_clean_intra_table_entries(s);
621                     continue;
622                 }
623
624                 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
625                 if (cbpc < 0){
626                     av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
627                     return -1;
628                 }
629                 if(cbpc == 20)
630                     goto try_again;
631
632                 s->cbp_table[xy]= cbpc&(8+3); //8 is dquant
633
634                 s->mb_intra = ((cbpc & 4) != 0);
635
636                 if(s->mb_intra){
637                     s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
638                     s->mbintra_table[xy]= 1;
639                     mot_val[0       ]= mot_val[2       ]=
640                     mot_val[0+stride]= mot_val[2+stride]= 0;
641                     mot_val[1       ]= mot_val[3       ]=
642                     mot_val[1+stride]= mot_val[3+stride]= 0;
643                 }else{
644                     if(s->mbintra_table[xy])
645                         ff_clean_intra_table_entries(s);
646
647                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
648                         s->mcsel= get_bits1(&s->gb);
649                     else s->mcsel= 0;
650
651                     if ((cbpc & 16) == 0) {
652                         /* 16x16 motion prediction */
653
654                         h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
655                         if(!s->mcsel){
656                             mx = h263_decode_motion(s, pred_x, s->f_code);
657                             if (mx >= 0xffff)
658                                 return -1;
659
660                             my = h263_decode_motion(s, pred_y, s->f_code);
661                             if (my >= 0xffff)
662                                 return -1;
663                             s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
664                         } else {
665                             mx = get_amv(s, 0);
666                             my = get_amv(s, 1);
667                             s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
668                         }
669
670                         mot_val[0       ]= mot_val[2       ] =
671                         mot_val[0+stride]= mot_val[2+stride]= mx;
672                         mot_val[1       ]= mot_val[3       ]=
673                         mot_val[1+stride]= mot_val[3+stride]= my;
674                     } else {
675                         int i;
676                         s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
677                         for(i=0;i<4;i++) {
678                             int16_t *mot_val= h263_pred_motion(s, i, 0, &pred_x, &pred_y);
679                             mx = h263_decode_motion(s, pred_x, s->f_code);
680                             if (mx >= 0xffff)
681                                 return -1;
682
683                             my = h263_decode_motion(s, pred_y, s->f_code);
684                             if (my >= 0xffff)
685                                 return -1;
686                             mot_val[0] = mx;
687                             mot_val[1] = my;
688                         }
689                     }
690                 }
691             }
692         }
693         s->mb_x= 0;
694     }
695
696     return mb_num;
697 }
698
699 /**
700  * decode second partition.
701  * @return <0 if an error occurred
702  */
703 static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count){
704     int mb_num=0;
705     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
706
707     s->mb_x= s->resync_mb_x;
708     s->first_slice_line=1;
709     for(s->mb_y= s->resync_mb_y; mb_num < mb_count; s->mb_y++){
710         ff_init_block_index(s);
711         for(; mb_num < mb_count && s->mb_x<s->mb_width; s->mb_x++){
712             const int xy= s->mb_x + s->mb_y*s->mb_stride;
713
714             mb_num++;
715             ff_update_block_index(s);
716             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
717                 s->first_slice_line=0;
718
719             if(s->pict_type==AV_PICTURE_TYPE_I){
720                 int ac_pred= get_bits1(&s->gb);
721                 int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
722                 if(cbpy<0){
723                     av_log(s->avctx, AV_LOG_ERROR, "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
724                     return -1;
725                 }
726
727                 s->cbp_table[xy]|= cbpy<<2;
728                 s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
729             }else{ /* P || S_TYPE */
730                 if (IS_INTRA(s->current_picture.f.mb_type[xy])) {
731                     int dir=0,i;
732                     int ac_pred = get_bits1(&s->gb);
733                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
734
735                     if(cbpy<0){
736                         av_log(s->avctx, AV_LOG_ERROR, "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
737                         return -1;
738                     }
739
740                     if(s->cbp_table[xy] & 8) {
741                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
742                     }
743                     s->current_picture.f.qscale_table[xy] = s->qscale;
744
745                     for(i=0; i<6; i++){
746                         int dc_pred_dir;
747                         int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
748                         if(dc < 0){
749                             av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
750                             return -1;
751                         }
752                         dir<<=1;
753                         if(dc_pred_dir) dir|=1;
754                     }
755                     s->cbp_table[xy]&= 3; //remove dquant
756                     s->cbp_table[xy]|= cbpy<<2;
757                     s->current_picture.f.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
758                     s->pred_dir_table[xy]= dir;
759                 } else if (IS_SKIP(s->current_picture.f.mb_type[xy])) {
760                     s->current_picture.f.qscale_table[xy] = s->qscale;
761                     s->cbp_table[xy]= 0;
762                 }else{
763                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
764
765                     if(cbpy<0){
766                         av_log(s->avctx, AV_LOG_ERROR, "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
767                         return -1;
768                     }
769
770                     if(s->cbp_table[xy] & 8) {
771                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
772                     }
773                     s->current_picture.f.qscale_table[xy] = s->qscale;
774
775                     s->cbp_table[xy]&= 3; //remove dquant
776                     s->cbp_table[xy]|= (cbpy^0xf)<<2;
777                 }
778             }
779         }
780         if(mb_num >= mb_count) return 0;
781         s->mb_x= 0;
782     }
783     return 0;
784 }
785
786 /**
787  * Decode the first and second partition.
788  * @return <0 if error (and sets error type in the error_status_table)
789  */
790 int ff_mpeg4_decode_partitions(MpegEncContext *s)
791 {
792     int mb_num;
793     const int part_a_error= s->pict_type==AV_PICTURE_TYPE_I ? (DC_ERROR|MV_ERROR) : MV_ERROR;
794     const int part_a_end  = s->pict_type==AV_PICTURE_TYPE_I ? (DC_END  |MV_END)   : MV_END;
795
796     mb_num= mpeg4_decode_partition_a(s);
797     if(mb_num<0){
798         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
799         return -1;
800     }
801
802     if(s->resync_mb_x + s->resync_mb_y*s->mb_width + mb_num > s->mb_num){
803         av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
804         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
805         return -1;
806     }
807
808     s->mb_num_left= mb_num;
809
810     if(s->pict_type==AV_PICTURE_TYPE_I){
811         while(show_bits(&s->gb, 9) == 1)
812             skip_bits(&s->gb, 9);
813         if(get_bits_long(&s->gb, 19)!=DC_MARKER){
814             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first I partition at %d %d\n", s->mb_x, s->mb_y);
815             return -1;
816         }
817     }else{
818         while(show_bits(&s->gb, 10) == 1)
819             skip_bits(&s->gb, 10);
820         if(get_bits(&s->gb, 17)!=MOTION_MARKER){
821             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first P partition at %d %d\n", s->mb_x, s->mb_y);
822             return -1;
823         }
824     }
825     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, part_a_end);
826
827     if( mpeg4_decode_partition_b(s, mb_num) < 0){
828         if(s->pict_type==AV_PICTURE_TYPE_P)
829             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, DC_ERROR);
830         return -1;
831     }else{
832         if(s->pict_type==AV_PICTURE_TYPE_P)
833             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, DC_END);
834     }
835
836     return 0;
837 }
838
839 /**
840  * Decode a block.
841  * @return <0 if an error occurred
842  */
843 static inline int mpeg4_decode_block(MpegEncContext * s, DCTELEM * block,
844                               int n, int coded, int intra, int rvlc)
845 {
846     int level, i, last, run;
847     int dc_pred_dir;
848     RLTable * rl;
849     RL_VLC_ELEM * rl_vlc;
850     const uint8_t * scan_table;
851     int qmul, qadd;
852
853     //Note intra & rvlc should be optimized away if this is inlined
854
855     if(intra) {
856       if(s->use_intra_dc_vlc){
857         /* DC coef */
858         if(s->partitioned_frame){
859             level = s->dc_val[0][ s->block_index[n] ];
860             if(n<4) level= FASTDIV((level + (s->y_dc_scale>>1)), s->y_dc_scale);
861             else    level= FASTDIV((level + (s->c_dc_scale>>1)), s->c_dc_scale);
862             dc_pred_dir= (s->pred_dir_table[s->mb_x + s->mb_y*s->mb_stride]<<n)&32;
863         }else{
864             level = mpeg4_decode_dc(s, n, &dc_pred_dir);
865             if (level < 0)
866                 return -1;
867         }
868         block[0] = level;
869         i = 0;
870       }else{
871             i = -1;
872             ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
873       }
874       if (!coded)
875           goto not_coded;
876
877       if(rvlc){
878           rl = &rvlc_rl_intra;
879           rl_vlc = rvlc_rl_intra.rl_vlc[0];
880       }else{
881           rl = &ff_mpeg4_rl_intra;
882           rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
883       }
884       if (s->ac_pred) {
885           if (dc_pred_dir == 0)
886               scan_table = s->intra_v_scantable.permutated; /* left */
887           else
888               scan_table = s->intra_h_scantable.permutated; /* top */
889       } else {
890             scan_table = s->intra_scantable.permutated;
891       }
892       qmul=1;
893       qadd=0;
894     } else {
895         i = -1;
896         if (!coded) {
897             s->block_last_index[n] = i;
898             return 0;
899         }
900         if(rvlc) rl = &rvlc_rl_inter;
901         else     rl = &ff_h263_rl_inter;
902
903         scan_table = s->intra_scantable.permutated;
904
905         if(s->mpeg_quant){
906             qmul=1;
907             qadd=0;
908             if(rvlc){
909                 rl_vlc = rvlc_rl_inter.rl_vlc[0];
910             }else{
911                 rl_vlc = ff_h263_rl_inter.rl_vlc[0];
912             }
913         }else{
914             qmul = s->qscale << 1;
915             qadd = (s->qscale - 1) | 1;
916             if(rvlc){
917                 rl_vlc = rvlc_rl_inter.rl_vlc[s->qscale];
918             }else{
919                 rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
920             }
921         }
922     }
923   {
924     OPEN_READER(re, &s->gb);
925     for(;;) {
926         UPDATE_CACHE(re, &s->gb);
927         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
928         if (level==0) {
929           /* escape */
930           if(rvlc){
931                 if(SHOW_UBITS(re, &s->gb, 1)==0){
932                     av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in rvlc esc\n");
933                     return -1;
934                 }; SKIP_CACHE(re, &s->gb, 1);
935
936                 last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
937                 run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
938                 SKIP_COUNTER(re, &s->gb, 1+1+6);
939                 UPDATE_CACHE(re, &s->gb);
940
941                 if(SHOW_UBITS(re, &s->gb, 1)==0){
942                     av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in rvlc esc\n");
943                     return -1;
944                 }; SKIP_CACHE(re, &s->gb, 1);
945
946                 level= SHOW_UBITS(re, &s->gb, 11); SKIP_CACHE(re, &s->gb, 11);
947
948                 if(SHOW_UBITS(re, &s->gb, 5)!=0x10){
949                     av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
950                     return -1;
951                 }; SKIP_CACHE(re, &s->gb, 5);
952
953                 level=  level * qmul + qadd;
954                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_CACHE(re, &s->gb, 1);
955                 SKIP_COUNTER(re, &s->gb, 1+11+5+1);
956
957                 i+= run + 1;
958                 if(last) i+=192;
959           }else{
960             int cache;
961             cache= GET_CACHE(re, &s->gb);
962
963             if(IS_3IV1)
964                 cache ^= 0xC0000000;
965
966             if (cache&0x80000000) {
967                 if (cache&0x40000000) {
968                     /* third escape */
969                     SKIP_CACHE(re, &s->gb, 2);
970                     last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
971                     run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
972                     SKIP_COUNTER(re, &s->gb, 2+1+6);
973                     UPDATE_CACHE(re, &s->gb);
974
975                     if(IS_3IV1){
976                         level= SHOW_SBITS(re, &s->gb, 12); LAST_SKIP_BITS(re, &s->gb, 12);
977                     }else{
978                         if(SHOW_UBITS(re, &s->gb, 1)==0){
979                             av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in 3. esc\n");
980                             return -1;
981                         }; SKIP_CACHE(re, &s->gb, 1);
982
983                         level= SHOW_SBITS(re, &s->gb, 12); SKIP_CACHE(re, &s->gb, 12);
984
985                         if(SHOW_UBITS(re, &s->gb, 1)==0){
986                             av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in 3. esc\n");
987                             return -1;
988                         }; LAST_SKIP_CACHE(re, &s->gb, 1);
989
990                         SKIP_COUNTER(re, &s->gb, 1+12+1);
991                     }
992
993                     if (level>0) level= level * qmul + qadd;
994                     else         level= level * qmul - qadd;
995
996                     if((unsigned)(level + 2048) > 4095){
997                         if(s->err_recognition & AV_EF_BITSTREAM){
998                             if(level > 2560 || level<-2560){
999                                 av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc, qp=%d\n", s->qscale);
1000                                 return -1;
1001                             }
1002                         }
1003                         level= level<0 ? -2048 : 2047;
1004                     }
1005
1006                     i+= run + 1;
1007                     if(last) i+=192;
1008                 } else {
1009                     /* second escape */
1010                     SKIP_BITS(re, &s->gb, 2);
1011                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1012                     i+= run + rl->max_run[run>>7][level/qmul] +1; //FIXME opt indexing
1013                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1014                     LAST_SKIP_BITS(re, &s->gb, 1);
1015                 }
1016             } else {
1017                 /* first escape */
1018                 SKIP_BITS(re, &s->gb, 1);
1019                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1020                 i+= run;
1021                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
1022                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1023                 LAST_SKIP_BITS(re, &s->gb, 1);
1024             }
1025           }
1026         } else {
1027             i+= run;
1028             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1029             LAST_SKIP_BITS(re, &s->gb, 1);
1030         }
1031         if (i > 62){
1032             i-= 192;
1033             if(i&(~63)){
1034                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1035                 return -1;
1036             }
1037
1038             block[scan_table[i]] = level;
1039             break;
1040         }
1041
1042         block[scan_table[i]] = level;
1043     }
1044     CLOSE_READER(re, &s->gb);
1045   }
1046  not_coded:
1047     if (intra) {
1048         if(!s->use_intra_dc_vlc){
1049             block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
1050
1051             i -= i>>31; //if(i == -1) i=0;
1052         }
1053
1054         mpeg4_pred_ac(s, block, n, dc_pred_dir);
1055         if (s->ac_pred) {
1056             i = 63; /* XXX: not optimal */
1057         }
1058     }
1059     s->block_last_index[n] = i;
1060     return 0;
1061 }
1062
1063 /**
1064  * decode partition C of one MB.
1065  * @return <0 if an error occurred
1066  */
1067 static int mpeg4_decode_partitioned_mb(MpegEncContext *s, DCTELEM block[6][64])
1068 {
1069     int cbp, mb_type;
1070     const int xy= s->mb_x + s->mb_y*s->mb_stride;
1071
1072     mb_type = s->current_picture.f.mb_type[xy];
1073     cbp = s->cbp_table[xy];
1074
1075     s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
1076
1077     if (s->current_picture.f.qscale_table[xy] != s->qscale) {
1078         ff_set_qscale(s, s->current_picture.f.qscale_table[xy]);
1079     }
1080
1081     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
1082         int i;
1083         for(i=0; i<4; i++){
1084             s->mv[0][i][0] = s->current_picture.f.motion_val[0][s->block_index[i]][0];
1085             s->mv[0][i][1] = s->current_picture.f.motion_val[0][s->block_index[i]][1];
1086         }
1087         s->mb_intra = IS_INTRA(mb_type);
1088
1089         if (IS_SKIP(mb_type)) {
1090             /* skip mb */
1091             for(i=0;i<6;i++)
1092                 s->block_last_index[i] = -1;
1093             s->mv_dir = MV_DIR_FORWARD;
1094             s->mv_type = MV_TYPE_16X16;
1095             if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
1096                 s->mcsel=1;
1097                 s->mb_skipped = 0;
1098             }else{
1099                 s->mcsel=0;
1100                 s->mb_skipped = 1;
1101             }
1102         }else if(s->mb_intra){
1103             s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
1104         }else if(!s->mb_intra){
1105 //            s->mcsel= 0; //FIXME do we need to init that
1106
1107             s->mv_dir = MV_DIR_FORWARD;
1108             if (IS_8X8(mb_type)) {
1109                 s->mv_type = MV_TYPE_8X8;
1110             } else {
1111                 s->mv_type = MV_TYPE_16X16;
1112             }
1113         }
1114     } else { /* I-Frame */
1115         s->mb_intra = 1;
1116         s->ac_pred = IS_ACPRED(s->current_picture.f.mb_type[xy]);
1117     }
1118
1119     if (!IS_SKIP(mb_type)) {
1120         int i;
1121         s->dsp.clear_blocks(s->block[0]);
1122         /* decode each block */
1123         for (i = 0; i < 6; i++) {
1124             if(mpeg4_decode_block(s, block[i], i, cbp&32, s->mb_intra, s->rvlc) < 0){
1125                 av_log(s->avctx, AV_LOG_ERROR, "texture corrupted at %d %d %d\n", s->mb_x, s->mb_y, s->mb_intra);
1126                 return -1;
1127             }
1128             cbp+=cbp;
1129         }
1130     }
1131
1132     /* per-MB end of slice check */
1133
1134     if(--s->mb_num_left <= 0){
1135         if(mpeg4_is_resync(s))
1136             return SLICE_END;
1137         else
1138             return SLICE_NOEND;
1139     }else{
1140         if(mpeg4_is_resync(s)){
1141             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1142             if(s->cbp_table[xy+delta])
1143                 return SLICE_END;
1144         }
1145         return SLICE_OK;
1146     }
1147 }
1148
1149 static int mpeg4_decode_mb(MpegEncContext *s,
1150                       DCTELEM block[6][64])
1151 {
1152     int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
1153     int16_t *mot_val;
1154     static int8_t quant_tab[4] = { -1, -2, 1, 2 };
1155     const int xy= s->mb_x + s->mb_y * s->mb_stride;
1156
1157     assert(s->h263_pred);
1158
1159     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
1160         do{
1161             if (get_bits1(&s->gb)) {
1162                 /* skip mb */
1163                 s->mb_intra = 0;
1164                 for(i=0;i<6;i++)
1165                     s->block_last_index[i] = -1;
1166                 s->mv_dir = MV_DIR_FORWARD;
1167                 s->mv_type = MV_TYPE_16X16;
1168                 if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
1169                     s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
1170                     s->mcsel=1;
1171                     s->mv[0][0][0]= get_amv(s, 0);
1172                     s->mv[0][0][1]= get_amv(s, 1);
1173
1174                     s->mb_skipped = 0;
1175                 }else{
1176                     s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
1177                     s->mcsel=0;
1178                     s->mv[0][0][0] = 0;
1179                     s->mv[0][0][1] = 0;
1180                     s->mb_skipped = 1;
1181                 }
1182                 goto end;
1183             }
1184             cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
1185             if (cbpc < 0){
1186                 av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1187                 return -1;
1188             }
1189         }while(cbpc == 20);
1190
1191         s->dsp.clear_blocks(s->block[0]);
1192         dquant = cbpc & 8;
1193         s->mb_intra = ((cbpc & 4) != 0);
1194         if (s->mb_intra) goto intra;
1195
1196         if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
1197             s->mcsel= get_bits1(&s->gb);
1198         else s->mcsel= 0;
1199         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
1200
1201         cbp = (cbpc & 3) | (cbpy << 2);
1202         if (dquant) {
1203             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1204         }
1205         if((!s->progressive_sequence) && (cbp || (s->workaround_bugs&FF_BUG_XVID_ILACE)))
1206             s->interlaced_dct= get_bits1(&s->gb);
1207
1208         s->mv_dir = MV_DIR_FORWARD;
1209         if ((cbpc & 16) == 0) {
1210             if(s->mcsel){
1211                 s->current_picture.f.mb_type[xy] = MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
1212                 /* 16x16 global motion prediction */
1213                 s->mv_type = MV_TYPE_16X16;
1214                 mx= get_amv(s, 0);
1215                 my= get_amv(s, 1);
1216                 s->mv[0][0][0] = mx;
1217                 s->mv[0][0][1] = my;
1218             }else if((!s->progressive_sequence) && get_bits1(&s->gb)){
1219                 s->current_picture.f.mb_type[xy] = MB_TYPE_16x8 | MB_TYPE_L0 | MB_TYPE_INTERLACED;
1220                 /* 16x8 field motion prediction */
1221                 s->mv_type= MV_TYPE_FIELD;
1222
1223                 s->field_select[0][0]= get_bits1(&s->gb);
1224                 s->field_select[0][1]= get_bits1(&s->gb);
1225
1226                 h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1227
1228                 for(i=0; i<2; i++){
1229                     mx = h263_decode_motion(s, pred_x, s->f_code);
1230                     if (mx >= 0xffff)
1231                         return -1;
1232
1233                     my = h263_decode_motion(s, pred_y/2, s->f_code);
1234                     if (my >= 0xffff)
1235                         return -1;
1236
1237                     s->mv[0][i][0] = mx;
1238                     s->mv[0][i][1] = my;
1239                 }
1240             }else{
1241                 s->current_picture.f.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
1242                 /* 16x16 motion prediction */
1243                 s->mv_type = MV_TYPE_16X16;
1244                 h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1245                 mx = h263_decode_motion(s, pred_x, s->f_code);
1246
1247                 if (mx >= 0xffff)
1248                     return -1;
1249
1250                 my = h263_decode_motion(s, pred_y, s->f_code);
1251
1252                 if (my >= 0xffff)
1253                     return -1;
1254                 s->mv[0][0][0] = mx;
1255                 s->mv[0][0][1] = my;
1256             }
1257         } else {
1258             s->current_picture.f.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
1259             s->mv_type = MV_TYPE_8X8;
1260             for(i=0;i<4;i++) {
1261                 mot_val = h263_pred_motion(s, i, 0, &pred_x, &pred_y);
1262                 mx = h263_decode_motion(s, pred_x, s->f_code);
1263                 if (mx >= 0xffff)
1264                     return -1;
1265
1266                 my = h263_decode_motion(s, pred_y, s->f_code);
1267                 if (my >= 0xffff)
1268                     return -1;
1269                 s->mv[0][i][0] = mx;
1270                 s->mv[0][i][1] = my;
1271                 mot_val[0] = mx;
1272                 mot_val[1] = my;
1273             }
1274         }
1275     } else if(s->pict_type==AV_PICTURE_TYPE_B) {
1276         int modb1; // first bit of modb
1277         int modb2; // second bit of modb
1278         int mb_type;
1279
1280         s->mb_intra = 0; //B-frames never contain intra blocks
1281         s->mcsel=0;      //     ...               true gmc blocks
1282
1283         if(s->mb_x==0){
1284             for(i=0; i<2; i++){
1285                 s->last_mv[i][0][0]=
1286                 s->last_mv[i][0][1]=
1287                 s->last_mv[i][1][0]=
1288                 s->last_mv[i][1][1]= 0;
1289             }
1290
1291             ff_thread_await_progress((AVFrame*)s->next_picture_ptr, s->mb_y, 0);
1292         }
1293
1294         /* if we skipped it in the future P Frame than skip it now too */
1295         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
1296
1297         if(s->mb_skipped){
1298                 /* skip mb */
1299             for(i=0;i<6;i++)
1300                 s->block_last_index[i] = -1;
1301
1302             s->mv_dir = MV_DIR_FORWARD;
1303             s->mv_type = MV_TYPE_16X16;
1304             s->mv[0][0][0] = 0;
1305             s->mv[0][0][1] = 0;
1306             s->mv[1][0][0] = 0;
1307             s->mv[1][0][1] = 0;
1308             s->current_picture.f.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
1309             goto end;
1310         }
1311
1312         modb1= get_bits1(&s->gb);
1313         if(modb1){
1314             mb_type= MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1; //like MB_TYPE_B_DIRECT but no vectors coded
1315             cbp=0;
1316         }else{
1317             modb2= get_bits1(&s->gb);
1318             mb_type= get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
1319             if(mb_type<0){
1320                 av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
1321                 return -1;
1322             }
1323             mb_type= mb_type_b_map[ mb_type ];
1324             if(modb2) cbp= 0;
1325             else{
1326                 s->dsp.clear_blocks(s->block[0]);
1327                 cbp= get_bits(&s->gb, 6);
1328             }
1329
1330             if ((!IS_DIRECT(mb_type)) && cbp) {
1331                 if(get_bits1(&s->gb)){
1332                     ff_set_qscale(s, s->qscale + get_bits1(&s->gb)*4 - 2);
1333                 }
1334             }
1335
1336             if(!s->progressive_sequence){
1337                 if(cbp)
1338                     s->interlaced_dct= get_bits1(&s->gb);
1339
1340                 if(!IS_DIRECT(mb_type) && get_bits1(&s->gb)){
1341                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
1342                     mb_type &= ~MB_TYPE_16x16;
1343
1344                     if(USES_LIST(mb_type, 0)){
1345                         s->field_select[0][0]= get_bits1(&s->gb);
1346                         s->field_select[0][1]= get_bits1(&s->gb);
1347                     }
1348                     if(USES_LIST(mb_type, 1)){
1349                         s->field_select[1][0]= get_bits1(&s->gb);
1350                         s->field_select[1][1]= get_bits1(&s->gb);
1351                     }
1352                 }
1353             }
1354
1355             s->mv_dir = 0;
1356             if((mb_type & (MB_TYPE_DIRECT2|MB_TYPE_INTERLACED)) == 0){
1357                 s->mv_type= MV_TYPE_16X16;
1358
1359                 if(USES_LIST(mb_type, 0)){
1360                     s->mv_dir = MV_DIR_FORWARD;
1361
1362                     mx = h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
1363                     my = h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
1364                     s->last_mv[0][1][0]= s->last_mv[0][0][0]= s->mv[0][0][0] = mx;
1365                     s->last_mv[0][1][1]= s->last_mv[0][0][1]= s->mv[0][0][1] = my;
1366                 }
1367
1368                 if(USES_LIST(mb_type, 1)){
1369                     s->mv_dir |= MV_DIR_BACKWARD;
1370
1371                     mx = h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
1372                     my = h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
1373                     s->last_mv[1][1][0]= s->last_mv[1][0][0]= s->mv[1][0][0] = mx;
1374                     s->last_mv[1][1][1]= s->last_mv[1][0][1]= s->mv[1][0][1] = my;
1375                 }
1376             }else if(!IS_DIRECT(mb_type)){
1377                 s->mv_type= MV_TYPE_FIELD;
1378
1379                 if(USES_LIST(mb_type, 0)){
1380                     s->mv_dir = MV_DIR_FORWARD;
1381
1382                     for(i=0; i<2; i++){
1383                         mx = h263_decode_motion(s, s->last_mv[0][i][0]  , s->f_code);
1384                         my = h263_decode_motion(s, s->last_mv[0][i][1]/2, s->f_code);
1385                         s->last_mv[0][i][0]=  s->mv[0][i][0] = mx;
1386                         s->last_mv[0][i][1]= (s->mv[0][i][1] = my)*2;
1387                     }
1388                 }
1389
1390                 if(USES_LIST(mb_type, 1)){
1391                     s->mv_dir |= MV_DIR_BACKWARD;
1392
1393                     for(i=0; i<2; i++){
1394                         mx = h263_decode_motion(s, s->last_mv[1][i][0]  , s->b_code);
1395                         my = h263_decode_motion(s, s->last_mv[1][i][1]/2, s->b_code);
1396                         s->last_mv[1][i][0]=  s->mv[1][i][0] = mx;
1397                         s->last_mv[1][i][1]= (s->mv[1][i][1] = my)*2;
1398                     }
1399                 }
1400             }
1401         }
1402
1403         if(IS_DIRECT(mb_type)){
1404             if(IS_SKIP(mb_type))
1405                 mx=my=0;
1406             else{
1407                 mx = h263_decode_motion(s, 0, 1);
1408                 my = h263_decode_motion(s, 0, 1);
1409             }
1410
1411             s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
1412             mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
1413         }
1414         s->current_picture.f.mb_type[xy] = mb_type;
1415     } else { /* I-Frame */
1416         do{
1417             cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
1418             if (cbpc < 0){
1419                 av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1420                 return -1;
1421             }
1422         }while(cbpc == 8);
1423
1424         dquant = cbpc & 4;
1425         s->mb_intra = 1;
1426 intra:
1427         s->ac_pred = get_bits1(&s->gb);
1428         if(s->ac_pred)
1429             s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
1430         else
1431             s->current_picture.f.mb_type[xy] = MB_TYPE_INTRA;
1432
1433         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
1434         if(cbpy<0){
1435             av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
1436             return -1;
1437         }
1438         cbp = (cbpc & 3) | (cbpy << 2);
1439
1440         s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
1441
1442         if (dquant) {
1443             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1444         }
1445
1446         if(!s->progressive_sequence)
1447             s->interlaced_dct= get_bits1(&s->gb);
1448
1449         s->dsp.clear_blocks(s->block[0]);
1450         /* decode each block */
1451         for (i = 0; i < 6; i++) {
1452             if (mpeg4_decode_block(s, block[i], i, cbp&32, 1, 0) < 0)
1453                 return -1;
1454             cbp+=cbp;
1455         }
1456         goto end;
1457     }
1458
1459     /* decode each block */
1460     for (i = 0; i < 6; i++) {
1461         if (mpeg4_decode_block(s, block[i], i, cbp&32, 0, 0) < 0)
1462             return -1;
1463         cbp+=cbp;
1464     }
1465 end:
1466
1467         /* per-MB end of slice check */
1468     if(s->codec_id==CODEC_ID_MPEG4){
1469         if(mpeg4_is_resync(s)){
1470             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1471
1472             if (s->pict_type == AV_PICTURE_TYPE_B && s->next_picture.f.mbskip_table[xy + delta]) {
1473                 ff_thread_await_progress((AVFrame*)s->next_picture_ptr,
1474                                         (s->mb_x + delta >= s->mb_width) ? FFMIN(s->mb_y+1, s->mb_height-1) : s->mb_y, 0);
1475             }
1476
1477             if (s->pict_type == AV_PICTURE_TYPE_B && s->next_picture.f.mbskip_table[xy + delta])
1478                 return SLICE_OK;
1479             return SLICE_END;
1480         }
1481     }
1482
1483     return SLICE_OK;
1484 }
1485
1486
1487 static int mpeg4_decode_gop_header(MpegEncContext * s, GetBitContext *gb){
1488     int hours, minutes, seconds;
1489     unsigned time_code = show_bits(gb, 18);
1490
1491     if (time_code & 0x40) {     /* marker_bit */
1492         hours   = time_code >> 13;
1493         minutes = time_code >>  7 & 0x3f;
1494         seconds = time_code       & 0x3f;
1495         s->time_base = seconds + 60*(minutes + 60*hours);
1496         skip_bits(gb, 20);      /* time_code, closed_gov, broken_link */
1497     } else {
1498         av_log(s->avctx, AV_LOG_WARNING, "GOP header missing marker_bit\n");
1499     }
1500
1501     return 0;
1502 }
1503
1504 static int mpeg4_decode_profile_level(MpegEncContext * s, GetBitContext *gb){
1505   int profile_and_level_indication;
1506
1507   profile_and_level_indication = get_bits(gb, 8);
1508
1509   s->avctx->profile = (profile_and_level_indication & 0xf0) >> 4;
1510   s->avctx->level   = (profile_and_level_indication & 0x0f);
1511
1512   // for Simple profile, level 0
1513   if (s->avctx->profile == 0 && s->avctx->level == 8) {
1514       s->avctx->level = 0;
1515   }
1516
1517   return 0;
1518 }
1519
1520 static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
1521     int width, height, vo_ver_id;
1522
1523     /* vol header */
1524     skip_bits(gb, 1); /* random access */
1525     s->vo_type= get_bits(gb, 8);
1526     if (get_bits1(gb) != 0) { /* is_ol_id */
1527         vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
1528         skip_bits(gb, 3); /* vo_priority */
1529     } else {
1530         vo_ver_id = 1;
1531     }
1532     s->aspect_ratio_info= get_bits(gb, 4);
1533     if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){
1534         s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
1535         s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
1536     }else{
1537         s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
1538     }
1539
1540     if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
1541         int chroma_format= get_bits(gb, 2);
1542         if(chroma_format!=CHROMA_420){
1543             av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
1544         }
1545         s->low_delay= get_bits1(gb);
1546         if(get_bits1(gb)){ /* vbv parameters */
1547             get_bits(gb, 15);   /* first_half_bitrate */
1548             skip_bits1(gb);     /* marker */
1549             get_bits(gb, 15);   /* latter_half_bitrate */
1550             skip_bits1(gb);     /* marker */
1551             get_bits(gb, 15);   /* first_half_vbv_buffer_size */
1552             skip_bits1(gb);     /* marker */
1553             get_bits(gb, 3);    /* latter_half_vbv_buffer_size */
1554             get_bits(gb, 11);   /* first_half_vbv_occupancy */
1555             skip_bits1(gb);     /* marker */
1556             get_bits(gb, 15);   /* latter_half_vbv_occupancy */
1557             skip_bits1(gb);     /* marker */
1558         }
1559     }else{
1560         // set low delay flag only once the smartest? low delay detection won't be overriden
1561         if(s->picture_number==0)
1562             s->low_delay=0;
1563     }
1564
1565     s->shape = get_bits(gb, 2); /* vol shape */
1566     if(s->shape != RECT_SHAPE) av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
1567     if(s->shape == GRAY_SHAPE && vo_ver_id != 1){
1568         av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
1569         skip_bits(gb, 4);  //video_object_layer_shape_extension
1570     }
1571
1572     check_marker(gb, "before time_increment_resolution");
1573
1574     s->avctx->time_base.den = get_bits(gb, 16);
1575     if(!s->avctx->time_base.den){
1576         av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
1577         s->avctx->time_base.num = 0;
1578         return -1;
1579     }
1580
1581     s->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
1582     if (s->time_increment_bits < 1)
1583         s->time_increment_bits = 1;
1584
1585     check_marker(gb, "before fixed_vop_rate");
1586
1587     if (get_bits1(gb) != 0) {   /* fixed_vop_rate  */
1588         s->avctx->time_base.num = get_bits(gb, s->time_increment_bits);
1589     }else
1590         s->avctx->time_base.num = 1;
1591
1592     s->t_frame=0;
1593
1594     if (s->shape != BIN_ONLY_SHAPE) {
1595         if (s->shape == RECT_SHAPE) {
1596             skip_bits1(gb);   /* marker */
1597             width = get_bits(gb, 13);
1598             skip_bits1(gb);   /* marker */
1599             height = get_bits(gb, 13);
1600             skip_bits1(gb);   /* marker */
1601             if(width && height && !(s->width && s->codec_tag == AV_RL32("MP4S"))){ /* they should be non zero but who knows ... */
1602                 s->width = width;
1603                 s->height = height;
1604             }
1605         }
1606
1607         s->progressive_sequence=
1608         s->progressive_frame= get_bits1(gb)^1;
1609         s->interlaced_dct=0;
1610         if(!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
1611             av_log(s->avctx, AV_LOG_INFO, "MPEG4 OBMC not supported (very likely buggy encoder)\n");   /* OBMC Disable */
1612         if (vo_ver_id == 1) {
1613             s->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
1614         } else {
1615             s->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
1616         }
1617         if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
1618         if(s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE){
1619             if(s->vol_sprite_usage==STATIC_SPRITE){
1620                 s->sprite_width = get_bits(gb, 13);
1621                 skip_bits1(gb); /* marker */
1622                 s->sprite_height= get_bits(gb, 13);
1623                 skip_bits1(gb); /* marker */
1624                 s->sprite_left  = get_bits(gb, 13);
1625                 skip_bits1(gb); /* marker */
1626                 s->sprite_top   = get_bits(gb, 13);
1627                 skip_bits1(gb); /* marker */
1628             }
1629             s->num_sprite_warping_points= get_bits(gb, 6);
1630             if(s->num_sprite_warping_points > 3){
1631                 av_log(s->avctx, AV_LOG_ERROR, "%d sprite_warping_points\n", s->num_sprite_warping_points);
1632                 s->num_sprite_warping_points= 0;
1633                 return -1;
1634             }
1635             s->sprite_warping_accuracy = get_bits(gb, 2);
1636             s->sprite_brightness_change= get_bits1(gb);
1637             if(s->vol_sprite_usage==STATIC_SPRITE)
1638                 s->low_latency_sprite= get_bits1(gb);
1639         }
1640         // FIXME sadct disable bit if verid!=1 && shape not rect
1641
1642         if (get_bits1(gb) == 1) {   /* not_8_bit */
1643             s->quant_precision = get_bits(gb, 4); /* quant_precision */
1644             if(get_bits(gb, 4)!=8) av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n"); /* bits_per_pixel */
1645             if(s->quant_precision!=5) av_log(s->avctx, AV_LOG_ERROR, "quant precision %d\n", s->quant_precision);
1646         } else {
1647             s->quant_precision = 5;
1648         }
1649
1650         // FIXME a bunch of grayscale shape things
1651
1652         if((s->mpeg_quant=get_bits1(gb))){ /* vol_quant_type */
1653             int i, v;
1654
1655             /* load default matrixes */
1656             for(i=0; i<64; i++){
1657                 int j= s->dsp.idct_permutation[i];
1658                 v= ff_mpeg4_default_intra_matrix[i];
1659                 s->intra_matrix[j]= v;
1660                 s->chroma_intra_matrix[j]= v;
1661
1662                 v= ff_mpeg4_default_non_intra_matrix[i];
1663                 s->inter_matrix[j]= v;
1664                 s->chroma_inter_matrix[j]= v;
1665             }
1666
1667             /* load custom intra matrix */
1668             if(get_bits1(gb)){
1669                 int last=0;
1670                 for(i=0; i<64; i++){
1671                     int j;
1672                     v= get_bits(gb, 8);
1673                     if(v==0) break;
1674
1675                     last= v;
1676                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1677                     s->intra_matrix[j]= v;
1678                     s->chroma_intra_matrix[j]= v;
1679                 }
1680
1681                 /* replicate last value */
1682                 for(; i<64; i++){
1683                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1684                     s->intra_matrix[j]= last;
1685                     s->chroma_intra_matrix[j]= last;
1686                 }
1687             }
1688
1689             /* load custom non intra matrix */
1690             if(get_bits1(gb)){
1691                 int last=0;
1692                 for(i=0; i<64; i++){
1693                     int j;
1694                     v= get_bits(gb, 8);
1695                     if(v==0) break;
1696
1697                     last= v;
1698                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1699                     s->inter_matrix[j]= v;
1700                     s->chroma_inter_matrix[j]= v;
1701                 }
1702
1703                 /* replicate last value */
1704                 for(; i<64; i++){
1705                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1706                     s->inter_matrix[j]= last;
1707                     s->chroma_inter_matrix[j]= last;
1708                 }
1709             }
1710
1711             // FIXME a bunch of grayscale shape things
1712         }
1713
1714         if(vo_ver_id != 1)
1715              s->quarter_sample= get_bits1(gb);
1716         else s->quarter_sample=0;
1717
1718         if(!get_bits1(gb)){
1719             int pos= get_bits_count(gb);
1720             int estimation_method= get_bits(gb, 2);
1721             if(estimation_method<2){
1722                 if(!get_bits1(gb)){
1723                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //opaque
1724                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //transparent
1725                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_cae
1726                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //inter_cae
1727                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //no_update
1728                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //upampling
1729                 }
1730                 if(!get_bits1(gb)){
1731                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_blocks
1732                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter_blocks
1733                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter4v_blocks
1734                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //not coded blocks
1735                 }
1736                 if(!check_marker(gb, "in complexity estimation part 1")){
1737                     skip_bits_long(gb, pos - get_bits_count(gb));
1738                     goto no_cplx_est;
1739                 }
1740                 if(!get_bits1(gb)){
1741                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_coeffs
1742                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_lines
1743                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //vlc_syms
1744                     s->cplx_estimation_trash_i += 4*get_bits1(gb); //vlc_bits
1745                 }
1746                 if(!get_bits1(gb)){
1747                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //apm
1748                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //npm
1749                     s->cplx_estimation_trash_b += 8*get_bits1(gb); //interpolate_mc_q
1750                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //forwback_mc_q
1751                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel2
1752                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel4
1753                 }
1754                 if(!check_marker(gb, "in complexity estimation part 2")){
1755                     skip_bits_long(gb, pos - get_bits_count(gb));
1756                     goto no_cplx_est;
1757                 }
1758                 if(estimation_method==1){
1759                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //sadct
1760                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //qpel
1761                 }
1762             }else
1763                 av_log(s->avctx, AV_LOG_ERROR, "Invalid Complexity estimation method %d\n", estimation_method);
1764         }else{
1765 no_cplx_est:
1766             s->cplx_estimation_trash_i=
1767             s->cplx_estimation_trash_p=
1768             s->cplx_estimation_trash_b= 0;
1769         }
1770
1771         s->resync_marker= !get_bits1(gb); /* resync_marker_disabled */
1772
1773         s->data_partitioning= get_bits1(gb);
1774         if(s->data_partitioning){
1775             s->rvlc= get_bits1(gb);
1776         }
1777
1778         if(vo_ver_id != 1) {
1779             s->new_pred= get_bits1(gb);
1780             if(s->new_pred){
1781                 av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
1782                 skip_bits(gb, 2); /* requested upstream message type */
1783                 skip_bits1(gb); /* newpred segment type */
1784             }
1785             s->reduced_res_vop= get_bits1(gb);
1786             if(s->reduced_res_vop) av_log(s->avctx, AV_LOG_ERROR, "reduced resolution VOP not supported\n");
1787         }
1788         else{
1789             s->new_pred=0;
1790             s->reduced_res_vop= 0;
1791         }
1792
1793         s->scalability= get_bits1(gb);
1794
1795         if (s->scalability) {
1796             GetBitContext bak= *gb;
1797             int h_sampling_factor_n;
1798             int h_sampling_factor_m;
1799             int v_sampling_factor_n;
1800             int v_sampling_factor_m;
1801
1802             s->hierachy_type= get_bits1(gb);
1803             skip_bits(gb, 4);  /* ref_layer_id */
1804             skip_bits1(gb);    /* ref_layer_sampling_dir */
1805             h_sampling_factor_n= get_bits(gb, 5);
1806             h_sampling_factor_m= get_bits(gb, 5);
1807             v_sampling_factor_n= get_bits(gb, 5);
1808             v_sampling_factor_m= get_bits(gb, 5);
1809             s->enhancement_type= get_bits1(gb);
1810
1811             if(   h_sampling_factor_n==0 || h_sampling_factor_m==0
1812                || v_sampling_factor_n==0 || v_sampling_factor_m==0){
1813                 /* illegal scalability header (VERY broken encoder),
1814                  * trying to workaround */
1815                 s->scalability=0;
1816                 *gb= bak;
1817             }else
1818                 av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
1819
1820             // bin shape stuff FIXME
1821         }
1822     }
1823     return 0;
1824 }
1825
1826 /**
1827  * Decode the user data stuff in the header.
1828  * Also initializes divx/xvid/lavc_version/build.
1829  */
1830 static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
1831     char buf[256];
1832     int i;
1833     int e;
1834     int ver = 0, build = 0, ver2 = 0, ver3 = 0;
1835     char last;
1836
1837     for(i=0; i<255 && get_bits_count(gb) < gb->size_in_bits; i++){
1838         if(show_bits(gb, 23) == 0) break;
1839         buf[i]= get_bits(gb, 8);
1840     }
1841     buf[i]=0;
1842
1843     /* divx detection */
1844     e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
1845     if(e<2)
1846         e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
1847     if(e>=2){
1848         s->divx_version= ver;
1849         s->divx_build= build;
1850         s->divx_packed= e==3 && last=='p';
1851         if(s->divx_packed && !s->showed_packed_warning) {
1852             av_log(s->avctx, AV_LOG_WARNING, "Invalid and inefficient vfw-avi packed B frames detected\n");
1853             s->showed_packed_warning=1;
1854         }
1855     }
1856
1857     /* libavcodec detection */
1858     e=sscanf(buf, "FFmpe%*[^b]b%d", &build)+3;
1859     if(e!=4)
1860         e=sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
1861     if(e!=4){
1862         e=sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3)+1;
1863         if (e>1)
1864             build= (ver<<16) + (ver2<<8) + ver3;
1865     }
1866     if(e!=4){
1867         if(strcmp(buf, "ffmpeg")==0){
1868             s->lavc_build= 4600;
1869         }
1870     }
1871     if(e==4){
1872         s->lavc_build= build;
1873     }
1874
1875     /* Xvid detection */
1876     e=sscanf(buf, "XviD%d", &build);
1877     if(e==1){
1878         s->xvid_build= build;
1879     }
1880
1881     return 0;
1882 }
1883
1884 static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
1885     int time_incr, time_increment;
1886
1887     s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I;        /* pict type: I = 0 , P = 1 */
1888     if(s->pict_type==AV_PICTURE_TYPE_B && s->low_delay && s->vol_control_parameters==0 && !(s->flags & CODEC_FLAG_LOW_DELAY)){
1889         av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
1890         s->low_delay=0;
1891     }
1892
1893     s->partitioned_frame= s->data_partitioning && s->pict_type!=AV_PICTURE_TYPE_B;
1894     if(s->partitioned_frame)
1895         s->decode_mb= mpeg4_decode_partitioned_mb;
1896     else
1897         s->decode_mb= mpeg4_decode_mb;
1898
1899     time_incr=0;
1900     while (get_bits1(gb) != 0)
1901         time_incr++;
1902
1903     check_marker(gb, "before time_increment");
1904
1905     if(s->time_increment_bits==0 || !(show_bits(gb, s->time_increment_bits+1)&1)){
1906         av_log(s->avctx, AV_LOG_ERROR, "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
1907
1908         for(s->time_increment_bits=1 ;s->time_increment_bits<16; s->time_increment_bits++){
1909             if (    s->pict_type == AV_PICTURE_TYPE_P
1910                 || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE)) {
1911                 if((show_bits(gb, s->time_increment_bits+6)&0x37) == 0x30) break;
1912             }else
1913                 if((show_bits(gb, s->time_increment_bits+5)&0x1F) == 0x18) break;
1914         }
1915
1916         av_log(s->avctx, AV_LOG_ERROR, "my guess is %d bits ;)\n",s->time_increment_bits);
1917     }
1918
1919     if(IS_3IV1) time_increment= get_bits1(gb); //FIXME investigate further
1920     else time_increment= get_bits(gb, s->time_increment_bits);
1921
1922     if(s->pict_type!=AV_PICTURE_TYPE_B){
1923         s->last_time_base= s->time_base;
1924         s->time_base+= time_incr;
1925         s->time= s->time_base*s->avctx->time_base.den + time_increment;
1926         if(s->workaround_bugs&FF_BUG_UMP4){
1927             if(s->time < s->last_non_b_time){
1928                 /* header is not mpeg-4-compatible, broken encoder,
1929                  * trying to workaround */
1930                 s->time_base++;
1931                 s->time+= s->avctx->time_base.den;
1932             }
1933         }
1934         s->pp_time= s->time - s->last_non_b_time;
1935         s->last_non_b_time= s->time;
1936     }else{
1937         s->time= (s->last_time_base + time_incr)*s->avctx->time_base.den + time_increment;
1938         s->pb_time= s->pp_time - (s->last_non_b_time - s->time);
1939         if(s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time<=0){
1940             /* messed up order, maybe after seeking? skipping current b-frame */
1941             return FRAME_SKIPPED;
1942         }
1943         ff_mpeg4_init_direct_mv(s);
1944
1945         if(s->t_frame==0) s->t_frame= s->pb_time;
1946         if(s->t_frame==0) s->t_frame=1; // 1/0 protection
1947         s->pp_field_time= (  ROUNDED_DIV(s->last_non_b_time, s->t_frame)
1948                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
1949         s->pb_field_time= (  ROUNDED_DIV(s->time, s->t_frame)
1950                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
1951         if(!s->progressive_sequence){
1952             if(s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1)
1953                 return FRAME_SKIPPED;
1954         }
1955     }
1956
1957     if(s->avctx->time_base.num)
1958         s->current_picture_ptr->f.pts = (s->time + s->avctx->time_base.num / 2) / s->avctx->time_base.num;
1959     else
1960         s->current_picture_ptr->f.pts = AV_NOPTS_VALUE;
1961     if(s->avctx->debug&FF_DEBUG_PTS)
1962         av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n",
1963                s->current_picture_ptr->f.pts);
1964
1965     check_marker(gb, "before vop_coded");
1966
1967     /* vop coded */
1968     if (get_bits1(gb) != 1){
1969         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
1970             av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
1971         return FRAME_SKIPPED;
1972     }
1973     if (s->shape != BIN_ONLY_SHAPE && ( s->pict_type == AV_PICTURE_TYPE_P
1974                           || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE))) {
1975         /* rounding type for motion estimation */
1976         s->no_rounding = get_bits1(gb);
1977     } else {
1978         s->no_rounding = 0;
1979     }
1980 //FIXME reduced res stuff
1981
1982      if (s->shape != RECT_SHAPE) {
1983          if (s->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
1984              skip_bits(gb, 13); /* width */
1985              skip_bits1(gb);   /* marker */
1986              skip_bits(gb, 13); /* height */
1987              skip_bits1(gb);   /* marker */
1988              skip_bits(gb, 13); /* hor_spat_ref */
1989              skip_bits1(gb);   /* marker */
1990              skip_bits(gb, 13); /* ver_spat_ref */
1991          }
1992          skip_bits1(gb); /* change_CR_disable */
1993
1994          if (get_bits1(gb) != 0) {
1995              skip_bits(gb, 8); /* constant_alpha_value */
1996          }
1997      }
1998 //FIXME complexity estimation stuff
1999
2000      if (s->shape != BIN_ONLY_SHAPE) {
2001          skip_bits_long(gb, s->cplx_estimation_trash_i);
2002          if(s->pict_type != AV_PICTURE_TYPE_I)
2003             skip_bits_long(gb, s->cplx_estimation_trash_p);
2004          if(s->pict_type == AV_PICTURE_TYPE_B)
2005             skip_bits_long(gb, s->cplx_estimation_trash_b);
2006
2007          s->intra_dc_threshold= mpeg4_dc_threshold[ get_bits(gb, 3) ];
2008          if(!s->progressive_sequence){
2009              s->top_field_first= get_bits1(gb);
2010              s->alternate_scan= get_bits1(gb);
2011          }else
2012              s->alternate_scan= 0;
2013      }
2014
2015      if(s->alternate_scan){
2016          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
2017          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
2018          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
2019          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
2020      } else{
2021          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
2022          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
2023          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
2024          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
2025      }
2026
2027      if(s->pict_type == AV_PICTURE_TYPE_S && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
2028          mpeg4_decode_sprite_trajectory(s, gb);
2029          if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
2030          if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
2031      }
2032
2033      if (s->shape != BIN_ONLY_SHAPE) {
2034          s->chroma_qscale= s->qscale = get_bits(gb, s->quant_precision);
2035          if(s->qscale==0){
2036              av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (qscale=0)\n");
2037              return -1; // makes no sense to continue, as there is nothing left from the image then
2038          }
2039
2040          if (s->pict_type != AV_PICTURE_TYPE_I) {
2041              s->f_code = get_bits(gb, 3);       /* fcode_for */
2042              if(s->f_code==0){
2043                  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (f_code=0)\n");
2044                  return -1; // makes no sense to continue, as the MV decoding will break very quickly
2045              }
2046          }else
2047              s->f_code=1;
2048
2049          if (s->pict_type == AV_PICTURE_TYPE_B) {
2050              s->b_code = get_bits(gb, 3);
2051          }else
2052              s->b_code=1;
2053
2054          if(s->avctx->debug&FF_DEBUG_PICT_INFO){
2055              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\n",
2056                  s->qscale, s->f_code, s->b_code,
2057                  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")),
2058                  gb->size_in_bits,s->progressive_sequence, s->alternate_scan, s->top_field_first,
2059                  s->quarter_sample ? "q" : "h", s->data_partitioning, s->resync_marker, s->num_sprite_warping_points,
2060                  s->sprite_warping_accuracy, 1-s->no_rounding, s->vo_type, s->vol_control_parameters ? " VOLC" : " ", s->intra_dc_threshold, s->cplx_estimation_trash_i, s->cplx_estimation_trash_p, s->cplx_estimation_trash_b);
2061          }
2062
2063          if(!s->scalability){
2064              if (s->shape!=RECT_SHAPE && s->pict_type!=AV_PICTURE_TYPE_I) {
2065                  skip_bits1(gb); // vop shape coding type
2066              }
2067          }else{
2068              if(s->enhancement_type){
2069                  int load_backward_shape= get_bits1(gb);
2070                  if(load_backward_shape){
2071                      av_log(s->avctx, AV_LOG_ERROR, "load backward shape isn't supported\n");
2072                  }
2073              }
2074              skip_bits(gb, 2); //ref_select_code
2075          }
2076      }
2077      /* detect buggy encoders which don't set the low_delay flag (divx4/xvid/opendivx)*/
2078      // note we cannot detect divx5 without b-frames easily (although it's buggy too)
2079      if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==-1 && s->picture_number==0){
2080          av_log(s->avctx, AV_LOG_WARNING, "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
2081          s->low_delay=1;
2082      }
2083
2084      s->picture_number++; // better than pic number==0 always ;)
2085
2086      s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support
2087      s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
2088
2089      if(s->workaround_bugs&FF_BUG_EDGE){
2090          s->h_edge_pos= s->width;
2091          s->v_edge_pos= s->height;
2092      }
2093      return 0;
2094 }
2095
2096 /**
2097  * Decode mpeg4 headers.
2098  * @return <0 if no VOP found (or a damaged one)
2099  *         FRAME_SKIPPED if a not coded VOP is found
2100  *         0 if a VOP is found
2101  */
2102 int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb)
2103 {
2104     unsigned startcode, v;
2105
2106     /* search next start code */
2107     align_get_bits(gb);
2108
2109     if(s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630){
2110         skip_bits(gb, 24);
2111         if(get_bits(gb, 8) == 0xF0)
2112             goto end;
2113     }
2114
2115     startcode = 0xff;
2116     for(;;) {
2117         if(get_bits_count(gb) >= gb->size_in_bits){
2118             if(gb->size_in_bits==8 && (s->divx_version>=0 || s->xvid_build>=0)){
2119                 av_log(s->avctx, AV_LOG_WARNING, "frame skip %d\n", gb->size_in_bits);
2120                 return FRAME_SKIPPED; //divx bug
2121             }else
2122                 return -1; //end of stream
2123         }
2124
2125         /* use the bits after the test */
2126         v = get_bits(gb, 8);
2127         startcode = ((startcode << 8) | v) & 0xffffffff;
2128
2129         if((startcode&0xFFFFFF00) != 0x100)
2130             continue; //no startcode
2131
2132         if(s->avctx->debug&FF_DEBUG_STARTCODE){
2133             av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
2134             if     (startcode<=0x11F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
2135             else if(startcode<=0x12F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
2136             else if(startcode<=0x13F) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2137             else if(startcode<=0x15F) av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
2138             else if(startcode<=0x1AF) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2139             else if(startcode==0x1B0) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
2140             else if(startcode==0x1B1) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
2141             else if(startcode==0x1B2) av_log(s->avctx, AV_LOG_DEBUG, "User Data");
2142             else if(startcode==0x1B3) av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
2143             else if(startcode==0x1B4) av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
2144             else if(startcode==0x1B5) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
2145             else if(startcode==0x1B6) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
2146             else if(startcode==0x1B7) av_log(s->avctx, AV_LOG_DEBUG, "slice start");
2147             else if(startcode==0x1B8) av_log(s->avctx, AV_LOG_DEBUG, "extension start");
2148             else if(startcode==0x1B9) av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
2149             else if(startcode==0x1BA) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
2150             else if(startcode==0x1BB) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
2151             else if(startcode==0x1BC) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
2152             else if(startcode==0x1BD) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
2153             else if(startcode==0x1BE) av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
2154             else if(startcode==0x1BF) av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
2155             else if(startcode==0x1C0) av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
2156             else if(startcode==0x1C1) av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
2157             else if(startcode==0x1C2) av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
2158             else if(startcode==0x1C3) av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
2159             else if(startcode<=0x1C5) av_log(s->avctx, AV_LOG_DEBUG, "reserved");
2160             else if(startcode<=0x1FF) av_log(s->avctx, AV_LOG_DEBUG, "System start");
2161             av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
2162         }
2163
2164         if(startcode >= 0x120 && startcode <= 0x12F){
2165             if(decode_vol_header(s, gb) < 0)
2166                 return -1;
2167         }
2168         else if(startcode == USER_DATA_STARTCODE){
2169             decode_user_data(s, gb);
2170         }
2171         else if(startcode == GOP_STARTCODE){
2172             mpeg4_decode_gop_header(s, gb);
2173         }
2174         else if(startcode == VOS_STARTCODE){
2175             mpeg4_decode_profile_level(s, gb);
2176         }
2177         else if(startcode == VOP_STARTCODE){
2178             break;
2179         }
2180
2181         align_get_bits(gb);
2182         startcode = 0xff;
2183     }
2184 end:
2185     if(s->flags& CODEC_FLAG_LOW_DELAY)
2186         s->low_delay=1;
2187     s->avctx->has_b_frames= !s->low_delay;
2188     return decode_vop_header(s, gb);
2189 }
2190
2191 static av_cold int decode_init(AVCodecContext *avctx)
2192 {
2193     MpegEncContext *s = avctx->priv_data;
2194     int ret;
2195     static int done = 0;
2196
2197     s->divx_version=
2198     s->divx_build=
2199     s->xvid_build=
2200     s->lavc_build= -1;
2201
2202     if((ret=ff_h263_decode_init(avctx)) < 0)
2203         return ret;
2204
2205     if (!done) {
2206         done = 1;
2207
2208         init_rl(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);
2209         init_rl(&rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
2210         init_rl(&rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
2211         INIT_VLC_RL(ff_mpeg4_rl_intra, 554);
2212         INIT_VLC_RL(rvlc_rl_inter, 1072);
2213         INIT_VLC_RL(rvlc_rl_intra, 1072);
2214         INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
2215                  &ff_mpeg4_DCtab_lum[0][1], 2, 1,
2216                  &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
2217         INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
2218                  &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
2219                  &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
2220         INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
2221                  &sprite_trajectory_tab[0][1], 4, 2,
2222                  &sprite_trajectory_tab[0][0], 4, 2, 128);
2223         INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
2224                  &mb_type_b_tab[0][1], 2, 1,
2225                  &mb_type_b_tab[0][0], 2, 1, 16);
2226     }
2227
2228     s->h263_pred = 1;
2229     s->low_delay = 0; //default, might be overriden in the vol header during header parsing
2230     s->decode_mb= mpeg4_decode_mb;
2231     s->time_increment_bits = 4; /* default value for broken headers */
2232     avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
2233
2234     return 0;
2235 }
2236
2237 static const AVProfile mpeg4_video_profiles[] = {
2238     { FF_PROFILE_MPEG4_SIMPLE,                    "Simple Profile" },
2239     { FF_PROFILE_MPEG4_SIMPLE_SCALABLE,           "Simple Scalable Profile" },
2240     { FF_PROFILE_MPEG4_CORE,                      "Core Profile" },
2241     { FF_PROFILE_MPEG4_MAIN,                      "Main Profile" },
2242     { FF_PROFILE_MPEG4_N_BIT,                     "N-bit Profile" },
2243     { FF_PROFILE_MPEG4_SCALABLE_TEXTURE,          "Scalable Texture Profile" },
2244     { FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION,     "Simple Face Animation Profile" },
2245     { FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE,    "Basic Animated Texture Profile" },
2246     { FF_PROFILE_MPEG4_HYBRID,                    "Hybrid Profile" },
2247     { FF_PROFILE_MPEG4_ADVANCED_REAL_TIME,        "Advanced Real Time Simple Profile" },
2248     { FF_PROFILE_MPEG4_CORE_SCALABLE,             "Code Scalable Profile" },
2249     { FF_PROFILE_MPEG4_ADVANCED_CODING,           "Advanced Coding Profile" },
2250     { FF_PROFILE_MPEG4_ADVANCED_CORE,             "Advanced Core Profile" },
2251     { FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE, "Advanced Scalable Texture Profile" },
2252     { FF_PROFILE_MPEG4_SIMPLE_STUDIO,             "Simple Studio Profile" },
2253     { FF_PROFILE_MPEG4_ADVANCED_SIMPLE,           "Advanced Simple Profile" },
2254 };
2255
2256 AVCodec ff_mpeg4_decoder = {
2257     .name           = "mpeg4",
2258     .type           = AVMEDIA_TYPE_VIDEO,
2259     .id             = CODEC_ID_MPEG4,
2260     .priv_data_size = sizeof(MpegEncContext),
2261     .init           = decode_init,
2262     .close          = ff_h263_decode_end,
2263     .decode         = ff_h263_decode_frame,
2264     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_FRAME_THREADS,
2265     .flush= ff_mpeg_flush,
2266     .max_lowres= 3,
2267     .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
2268     .pix_fmts= ff_hwaccel_pixfmt_list_420,
2269     .profiles = NULL_IF_CONFIG_SMALL(mpeg4_video_profiles),
2270     .update_thread_context= ONLY_IF_THREADS_ENABLED(ff_mpeg_update_thread_context)
2271 };
2272
2273
2274 #if CONFIG_MPEG4_VDPAU_DECODER
2275 AVCodec ff_mpeg4_vdpau_decoder = {
2276     .name           = "mpeg4_vdpau",
2277     .type           = AVMEDIA_TYPE_VIDEO,
2278     .id             = CODEC_ID_MPEG4,
2279     .priv_data_size = sizeof(MpegEncContext),
2280     .init           = decode_init,
2281     .close          = ff_h263_decode_end,
2282     .decode         = ff_h263_decode_frame,
2283     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_HWACCEL_VDPAU,
2284     .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
2285     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_VDPAU_MPEG4, PIX_FMT_NONE},
2286 };
2287 #endif