per file doxy
[ffmpeg.git] / libavcodec / h263dec.c
1 /*
2  * H.263 decoder
3  * Copyright (c) 2001 Fabrice Bellard.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with this library; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19  
20 /**
21  * @file h263dec.c
22  * H.263 decoder.
23  */
24  
25 #include "avcodec.h"
26 #include "dsputil.h"
27 #include "mpegvideo.h"
28
29 //#define DEBUG
30 //#define PRINT_FRAME_TIME
31 #ifdef PRINT_FRAME_TIME
32 static inline long long rdtsc()
33 {
34         long long l;
35         asm volatile(   "rdtsc\n\t"
36                 : "=A" (l)
37         );
38 //      printf("%d\n", int(l/1000));
39         return l;
40 }
41 #endif
42
43 int ff_h263_decode_init(AVCodecContext *avctx)
44 {
45     MpegEncContext *s = avctx->priv_data;
46
47     s->avctx = avctx;
48     s->out_format = FMT_H263;
49
50     s->width = avctx->width;
51     s->height = avctx->height;
52     s->workaround_bugs= avctx->workaround_bugs;
53
54     // set defaults
55     s->quant_precision=5;
56     s->progressive_sequence=1;
57     s->decode_mb= ff_h263_decode_mb;
58     s->low_delay= 1;
59     avctx->pix_fmt= PIX_FMT_YUV420P;
60
61     /* select sub codec */
62     switch(avctx->codec->id) {
63     case CODEC_ID_H263:
64         s->gob_number = 0;
65         break;
66     case CODEC_ID_MPEG4:
67         s->time_increment_bits = 4; /* default value for broken headers */
68         s->h263_pred = 1;
69         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
70         break;
71     case CODEC_ID_MSMPEG4V1:
72         s->h263_msmpeg4 = 1;
73         s->h263_pred = 1;
74         s->msmpeg4_version=1;
75         break;
76     case CODEC_ID_MSMPEG4V2:
77         s->h263_msmpeg4 = 1;
78         s->h263_pred = 1;
79         s->msmpeg4_version=2;
80         break;
81     case CODEC_ID_MSMPEG4V3:
82         s->h263_msmpeg4 = 1;
83         s->h263_pred = 1;
84         s->msmpeg4_version=3;
85         break;
86     case CODEC_ID_WMV1:
87         s->h263_msmpeg4 = 1;
88         s->h263_pred = 1;
89         s->msmpeg4_version=4;
90         break;
91     case CODEC_ID_WMV2:
92         s->h263_msmpeg4 = 1;
93         s->h263_pred = 1;
94         s->msmpeg4_version=5;
95         break;
96     case CODEC_ID_H263I:
97         s->h263_intel = 1;
98         break;
99     default:
100         return -1;
101     }
102     s->codec_id= avctx->codec->id;
103
104     /* for h263, we allocate the images after having read the header */
105     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
106         if (MPV_common_init(s) < 0)
107             return -1;
108
109     if (s->h263_msmpeg4)
110         ff_msmpeg4_decode_init(s);
111     else
112         h263_decode_init_vlc(s);
113     
114     return 0;
115 }
116
117 int ff_h263_decode_end(AVCodecContext *avctx)
118 {
119     MpegEncContext *s = avctx->priv_data;
120
121     MPV_common_end(s);
122     return 0;
123 }
124
125 /**
126  * retunrs the number of bytes consumed for building the current frame
127  */
128 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
129     int pos= (get_bits_count(&s->gb)+7)>>3;
130     
131     if(s->divx_version>=500){
132         //we would have to scan through the whole buf to handle the weird reordering ...
133         return buf_size; 
134     }else if(s->flags&CODEC_FLAG_TRUNCATED){
135         pos -= s->parse_context.last_index;
136         if(pos<0) pos=0; // padding is not really read so this might be -1
137         return pos;
138     }else{
139         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
140         if(pos+10>buf_size) pos=buf_size; // oops ;)
141
142         return pos;
143     }
144 }
145
146 static int decode_slice(MpegEncContext *s){
147     s->last_resync_gb= s->gb;
148     s->first_slice_line= 1;
149         
150     s->resync_mb_x= s->mb_x;
151     s->resync_mb_y= s->mb_y;
152
153     s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
154     s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
155     
156     if(s->partitioned_frame){
157         const int qscale= s->qscale;
158
159         if(s->codec_id==CODEC_ID_MPEG4){
160             if(ff_mpeg4_decode_partitions(s) < 0)
161                 return -1; 
162         }
163         
164         /* restore variables which where modified */
165         s->first_slice_line=1;
166         s->mb_x= s->resync_mb_x;
167         s->mb_y= s->resync_mb_y;
168         s->qscale= qscale;
169         s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
170         s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
171     }
172
173     for(; s->mb_y < s->mb_height; s->mb_y++) {
174         /* per-row end of slice checks */
175         if(s->msmpeg4_version){
176             if(s->resync_mb_y + s->slice_height == s->mb_y){
177                 const int xy= s->mb_x + s->mb_y*s->mb_width;
178                 s->error_status_table[xy-1]|= AC_END|DC_END|MV_END;
179                 return 0;
180             }
181         }
182         
183         if(s->msmpeg4_version==1){
184             s->last_dc[0]=
185             s->last_dc[1]=
186             s->last_dc[2]= 128;
187         }
188     
189         ff_init_block_index(s);
190         for(; s->mb_x < s->mb_width; s->mb_x++) {
191             int ret;
192
193             ff_update_block_index(s);
194
195             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
196                 s->first_slice_line=0; 
197             }
198
199             /* DCT & quantize */
200             s->dsp.clear_blocks(s->block[0]);
201             
202             s->mv_dir = MV_DIR_FORWARD;
203             s->mv_type = MV_TYPE_16X16;
204 //            s->mb_skiped = 0;
205 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
206             ret= s->decode_mb(s, s->block);
207             
208             MPV_decode_mb(s, s->block);
209
210             if(ret<0){
211                 const int xy= s->mb_x + s->mb_y*s->mb_width;
212                 if(ret==SLICE_END){
213 //printf("%d %d %d %06X\n", s->mb_x, s->mb_y, s->gb.size*8 - get_bits_count(&s->gb), show_bits(&s->gb, 24));
214                     s->error_status_table[xy]|= AC_END;
215                     if(!s->partitioned_frame)
216                         s->error_status_table[xy]|= MV_END|DC_END;
217
218                     s->padding_bug_score--;
219                         
220                     if(++s->mb_x >= s->mb_width){
221                         s->mb_x=0;
222                         ff_draw_horiz_band(s, s->mb_y*16, 16);
223                         s->mb_y++;
224                     }
225                     return 0; 
226                 }else if(ret==SLICE_NOEND){
227                     fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
228                     return -1;
229                 }
230                 fprintf(stderr,"Error at MB: %d\n", xy);
231                 s->error_status_table[xy]|= AC_ERROR;
232                 if(!s->partitioned_frame)
233                     s->error_status_table[xy]|= DC_ERROR|MV_ERROR;
234     
235                 return -1;
236             }
237         }
238         
239         ff_draw_horiz_band(s, s->mb_y*16, 16);
240         
241         s->mb_x= 0;
242     }
243     
244     assert(s->mb_x==0 && s->mb_y==s->mb_height);
245
246     /* try to detect the padding bug */
247     if(      s->codec_id==CODEC_ID_MPEG4
248        &&   (s->workaround_bugs&FF_BUG_AUTODETECT) 
249        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
250        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
251 //       &&   !s->resync_marker
252        &&   !s->data_partitioning){
253         
254         const int bits_count= get_bits_count(&s->gb);
255         const int bits_left = s->gb.size_in_bits - bits_count;
256         
257         if(bits_left==0){
258             s->padding_bug_score+=16;
259         }else if(bits_left>8){
260             s->padding_bug_score++;
261         } else if(bits_left != 1){
262             int v= show_bits(&s->gb, 8);
263             v|= 0x7F >> (7-(bits_count&7));
264
265             if(v==0x7F)
266                 s->padding_bug_score--;
267             else
268                 s->padding_bug_score++;            
269         }                          
270     }
271
272     // handle formats which dont have unique end markers
273     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
274         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
275         int max_extra=7;
276         
277         /* no markers in M$ crap */
278         if(s->msmpeg4_version && s->pict_type==I_TYPE)
279             max_extra+= 17;
280         
281         /* buggy padding but the frame should still end approximately at the bitstream end */
282         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
283             max_extra+= 48;
284         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
285             max_extra+= 256*256*256*64;
286         
287         if(left>max_extra){
288             fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
289         }
290         else if(left<0){
291             fprintf(stderr, "overreading %d bits\n", -left);
292         }else
293             s->error_status_table[s->mb_num-1]|= AC_END|MV_END|DC_END;
294         
295         return 0;
296     }
297
298     fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n", 
299             s->gb.size_in_bits - get_bits_count(&s->gb),
300             show_bits(&s->gb, 24));
301     return -1;
302 }
303
304 /**
305  * finds the end of the current frame in the bitstream.
306  * @return the position of the first byte of the next frame, or -1
307  */
308 static int mpeg4_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
309     ParseContext *pc= &s->parse_context;
310     int vop_found, i;
311     uint32_t state;
312     
313     vop_found= pc->frame_start_found;
314     state= pc->state;
315     
316     i=0;
317     if(!vop_found){
318         for(i=0; i<buf_size; i++){
319             state= (state<<8) | buf[i];
320             if(state == 0x1B6){
321                 i++;
322                 vop_found=1;
323                 break;
324             }
325         }
326     }
327     
328     for(; i<buf_size; i++){
329         state= (state<<8) | buf[i];
330         if((state&0xFFFFFF00) == 0x100){
331             pc->frame_start_found=0;
332             pc->state=-1; 
333             return i-3;
334         }
335     }
336     pc->frame_start_found= vop_found;
337     pc->state= state;
338     return -1;
339 }
340
341 /**
342  * draws an line from (ex, ey) -> (sx, sy).
343  * @param w width of the image
344  * @param h height of the image
345  * @param stride stride/linesize of the image
346  * @param color color of the arrow
347  */
348 static void draw_line(uint8_t *buf, int sx, int sy, int ex, int ey, int w, int h, int stride, int color){
349     int t, x, y, f;
350     
351     ex= clip(ex, 0, w-1);
352     ey= clip(ey, 0, h-1);
353     
354     buf[sy*stride + sx]+= color;
355     
356     if(ABS(ex - sx) > ABS(ey - sy)){
357         if(sx > ex){
358             t=sx; sx=ex; ex=t;
359             t=sy; sy=ey; ey=t;
360         }
361         buf+= sx + sy*stride;
362         ex-= sx;
363         f= ((ey-sy)<<16)/ex;
364         for(x= 0; x <= ex; x++){
365             y= ((x*f) + (1<<15))>>16;
366             buf[y*stride + x]+= color;
367         }
368     }else{
369         if(sy > ey){
370             t=sx; sx=ex; ex=t;
371             t=sy; sy=ey; ey=t;
372         }
373         buf+= sx + sy*stride;
374         ey-= sy;
375         if(ey) f= ((ex-sx)<<16)/ey;
376         else   f= 0;
377         for(y= 0; y <= ey; y++){
378             x= ((y*f) + (1<<15))>>16;
379             buf[y*stride + x]+= color;
380         }
381     }
382 }
383
384 /**
385  * draws an arrow from (ex, ey) -> (sx, sy).
386  * @param w width of the image
387  * @param h height of the image
388  * @param stride stride/linesize of the image
389  * @param color color of the arrow
390  */
391 static void draw_arrow(uint8_t *buf, int sx, int sy, int ex, int ey, int w, int h, int stride, int color){ 
392     int dx= ex - sx;
393     int dy= ey - sy;
394     
395     if(dx*dx + dy*dy > 3*3){
396         int rx=  dx + dy;
397         int ry= -dx + dy;
398         int length= ff_sqrt((rx*rx + ry*ry)<<8);
399         
400         //FIXME subpixel accuracy
401         rx= ROUNDED_DIV(rx*3<<4, length);
402         ry= ROUNDED_DIV(ry*3<<4, length);
403         
404         draw_line(buf, sx, sy, sx + rx, sy + ry, w, h, stride, color);
405         draw_line(buf, sx, sy, sx - ry, sy + rx, w, h, stride, color);
406     }
407     draw_line(buf, sx, sy, ex, ey, w, h, stride, color);
408 }
409
410 int ff_h263_decode_frame(AVCodecContext *avctx, 
411                              void *data, int *data_size,
412                              uint8_t *buf, int buf_size)
413 {
414     MpegEncContext *s = avctx->priv_data;
415     int ret,i;
416     AVFrame *pict = data; 
417     float new_aspect;
418     
419 #ifdef PRINT_FRAME_TIME
420 uint64_t time= rdtsc();
421 #endif
422 #ifdef DEBUG
423     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
424     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
425 #endif
426     s->flags= avctx->flags;
427
428     *data_size = 0;
429    
430    /* no supplementary picture */
431     if (buf_size == 0) {
432         return 0;
433     }
434
435     if(s->flags&CODEC_FLAG_TRUNCATED){
436         int next;
437         
438         if(s->codec_id==CODEC_ID_MPEG4){
439             next= mpeg4_find_frame_end(s, buf, buf_size);
440         }else{
441             fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
442             return -1;
443         }
444         
445         if( ff_combine_frame(s, next, &buf, &buf_size) < 0 )
446             return buf_size;
447     }
448
449 retry:
450     
451     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
452         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
453     }else
454         init_get_bits(&s->gb, buf, buf_size*8);
455     s->bitstream_buffer_size=0;
456
457     if (!s->context_initialized) {
458         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
459             return -1;
460     }
461       
462     /* let's go :-) */
463     if (s->msmpeg4_version==5) {
464         ret= ff_wmv2_decode_picture_header(s);
465     } else if (s->msmpeg4_version) {
466         ret = msmpeg4_decode_picture_header(s);
467     } else if (s->h263_pred) {
468         if(s->avctx->extradata_size && s->picture_number==0){
469             GetBitContext gb;
470             
471             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
472             ret = ff_mpeg4_decode_picture_header(s, &gb);
473         }
474         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
475
476         if(s->flags& CODEC_FLAG_LOW_DELAY)
477             s->low_delay=1;
478     } else if (s->h263_intel) {
479         ret = intel_h263_decode_picture_header(s);
480     } else {
481         ret = h263_decode_picture_header(s);
482     }
483     avctx->has_b_frames= !s->low_delay;
484
485     if(s->workaround_bugs&FF_BUG_AUTODETECT){
486         if(s->padding_bug_score > -2 && !s->data_partitioning)
487             s->workaround_bugs |=  FF_BUG_NO_PADDING;
488         else
489             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
490
491         if(s->avctx->fourcc == ff_get_fourcc("XVIX")) 
492             s->workaround_bugs|= FF_BUG_XVID_ILACE;
493 #if 0
494         if(s->avctx->fourcc == ff_get_fourcc("MP4S")) 
495             s->workaround_bugs|= FF_BUG_AC_VLC;
496         
497         if(s->avctx->fourcc == ff_get_fourcc("M4S2")) 
498             s->workaround_bugs|= FF_BUG_AC_VLC;
499 #endif
500         if(s->avctx->fourcc == ff_get_fourcc("UMP4")){
501             s->workaround_bugs|= FF_BUG_UMP4;
502             s->workaround_bugs|= FF_BUG_AC_VLC;
503         }
504
505         if(s->divx_version){
506             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
507         }
508
509         if(s->divx_version>502){
510             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
511         }
512
513         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
514             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
515         
516         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
517             s->padding_bug_score= 256*256*256*64;
518         
519         if(s->xvid_build && s->xvid_build<=3)
520             s->padding_bug_score= 256*256*256*64;
521         
522         if(s->xvid_build && s->xvid_build<=1)
523             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
524
525 #define SET_QPEL_FUNC(postfix1, postfix2) \
526     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
527     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
528     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
529
530         if(s->lavc_build && s->lavc_build<4653)
531             s->workaround_bugs|= FF_BUG_STD_QPEL;
532         
533         if(s->lavc_build && s->lavc_build<4655)
534             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
535
536         if(s->divx_version)
537             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
538 //printf("padding_bug_score: %d\n", s->padding_bug_score);
539         if(s->divx_version==501 && s->divx_build==20020416)
540             s->padding_bug_score= 256*256*256*64;
541 #if 0
542         if(s->divx_version==500)
543             s->padding_bug_score= 256*256*256*64;
544
545         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
546          * lets hope this at least works
547          */
548         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
549            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
550             s->workaround_bugs|= FF_BUG_NO_PADDING;
551         
552         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
553             s->workaround_bugs|= FF_BUG_NO_PADDING;
554 #endif
555     }
556     
557     if(s->workaround_bugs& FF_BUG_STD_QPEL){
558         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
559         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
560         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
561         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
562         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
563         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
564
565         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
566         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
567         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
568         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
569         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
570         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
571     }
572
573 #if 0 // dump bits per frame / qp / complexity
574 {
575     static FILE *f=NULL;
576     if(!f) f=fopen("rate_qp_cplx.txt", "w");
577     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
578 }
579 #endif
580        
581         /* After H263 & mpeg4 header decode we have the height, width,*/
582         /* and other parameters. So then we could init the picture   */
583         /* FIXME: By the way H263 decoder is evolving it should have */
584         /* an H263EncContext                                         */
585     if(s->aspected_height)
586         new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
587     else
588         new_aspect=0;
589     
590     if (   s->width != avctx->width || s->height != avctx->height 
591         || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
592         /* H.263 could change picture size any time */
593         MPV_common_end(s);
594         s->context_initialized=0;
595     }
596     if (!s->context_initialized) {
597         avctx->width = s->width;
598         avctx->height = s->height;
599         avctx->aspect_ratio= new_aspect;
600
601         goto retry;
602     }
603
604     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
605         s->gob_index = ff_h263_get_gob_height(s);
606
607     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
608     /* skip if the header was thrashed */
609     if (ret < 0){
610         fprintf(stderr, "header damaged\n");
611         return -1;
612     }
613     
614     // for hurry_up==5
615     s->current_picture.pict_type= s->pict_type;
616     s->current_picture.key_frame= s->pict_type == I_TYPE;
617
618     /* skip b frames if we dont have reference frames */
619     if(s->last_picture.data[0]==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
620     /* skip b frames if we are in a hurry */
621     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
622     /* skip everything if we are in a hurry>=5 */
623     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
624     
625     if(s->next_p_frame_damaged){
626         if(s->pict_type==B_TYPE)
627             return get_consumed_bytes(s, buf_size);
628         else
629             s->next_p_frame_damaged=0;
630     }
631
632     if(MPV_frame_start(s, avctx) < 0)
633         return -1;
634
635 #ifdef DEBUG
636     printf("qscale=%d\n", s->qscale);
637 #endif
638
639     if(s->error_resilience)
640         memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(uint8_t));
641     
642     /* decode each macroblock */
643     s->block_wrap[0]=
644     s->block_wrap[1]=
645     s->block_wrap[2]=
646     s->block_wrap[3]= s->mb_width*2 + 2;
647     s->block_wrap[4]=
648     s->block_wrap[5]= s->mb_width + 2;
649     s->mb_x=0; 
650     s->mb_y=0;
651     
652     decode_slice(s);
653     s->error_status_table[0]|= VP_START;
654     while(s->mb_y<s->mb_height && s->gb.size_in_bits - get_bits_count(&s->gb)>16){
655         if(s->msmpeg4_version){
656             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
657                 break;
658         }else{
659             if(ff_h263_resync(s)<0)
660                 break;
661         }
662         
663         if(s->msmpeg4_version<4 && s->h263_pred)
664             ff_mpeg4_clean_buffers(s);
665
666         decode_slice(s);
667
668         s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
669     }
670
671     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
672         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
673             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
674         }
675     
676     /* divx 5.01+ bistream reorder stuff */
677     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
678         int current_pos= get_bits_count(&s->gb)>>3;
679
680         if(   buf_size - current_pos > 5 
681            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
682             int i;
683             int startcode_found=0;
684             for(i=current_pos; i<buf_size-3; i++){
685                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
686                     startcode_found=1;
687                     break;
688                 }
689             }
690             if(startcode_found){
691                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
692                 s->bitstream_buffer_size= buf_size - current_pos;
693             }
694         }
695     }
696
697     if(s->error_resilience){
698         int error=0, num_end_markers=0;
699         for(i=0; i<s->mb_num; i++){
700             int status= s->error_status_table[i];
701 #if 0
702             if(i%s->mb_width == 0) printf("\n");
703             printf("%2X ", status); 
704 #endif
705             if(status==0) continue;
706
707             if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
708                 error=1;
709             if(status&VP_START){
710                 if(num_end_markers) 
711                     error=1;
712                 num_end_markers=3;
713             }
714             if(status&AC_END)
715                 num_end_markers--;
716             if(status&DC_END)
717                 num_end_markers--;
718             if(status&MV_END)
719                 num_end_markers--;
720         }
721         if(num_end_markers || error){
722             fprintf(stderr, "concealing errors\n");
723             ff_error_resilience(s);
724         }
725     }
726
727     MPV_frame_end(s);
728
729     if((avctx->debug&FF_DEBUG_VIS_MV) && s->last_picture.data[0]){
730         const int shift= 1 + s->quarter_sample;
731         int mb_y;
732         uint8_t *ptr= s->last_picture.data[0];
733         s->low_delay=0; //needed to see the vectors without trashing the buffers
734
735         for(mb_y=0; mb_y<s->mb_height; mb_y++){
736             int mb_x;
737             for(mb_x=0; mb_x<s->mb_width; mb_x++){
738                 const int mb_index= mb_x + mb_y*s->mb_width;
739                 if(s->co_located_type_table[mb_index] == MV_TYPE_8X8){
740                     int i;
741                     for(i=0; i<4; i++){
742                         int sx= mb_x*16 + 4 + 8*(i&1);
743                         int sy= mb_y*16 + 4 + 8*(i>>1);
744                         int xy= 1 + mb_x*2 + (i&1) + (mb_y*2 + 1 + (i>>1))*(s->mb_width*2 + 2);
745                         int mx= (s->motion_val[xy][0]>>shift) + sx;
746                         int my= (s->motion_val[xy][1]>>shift) + sy;
747                         draw_arrow(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
748                     }
749                 }else{
750                     int sx= mb_x*16 + 8;
751                     int sy= mb_y*16 + 8;
752                     int xy= 1 + mb_x*2 + (mb_y*2 + 1)*(s->mb_width*2 + 2);
753                     int mx= (s->motion_val[xy][0]>>shift) + sx;
754                     int my= (s->motion_val[xy][1]>>shift) + sy;
755                     draw_arrow(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
756                 }
757                 s->mbskip_table[mb_index]=0;
758             }
759         }
760     }
761
762
763     if(s->pict_type==B_TYPE || s->low_delay){
764         *pict= *(AVFrame*)&s->current_picture;
765     } else {
766         *pict= *(AVFrame*)&s->last_picture;
767     }
768
769     if(avctx->debug&FF_DEBUG_QP){
770         int8_t *qtab= pict->qscale_table;
771         int x,y;
772         
773         for(y=0; y<s->mb_height; y++){
774             for(x=0; x<s->mb_width; x++){
775                 printf("%2d ", qtab[x + y*s->mb_width]);
776             }
777             printf("\n");
778         }
779         printf("\n");
780     }
781
782     /* Return the Picture timestamp as the frame number */
783     /* we substract 1 because it is added on utils.c    */
784     avctx->frame_number = s->picture_number - 1;
785
786     /* dont output the last pic after seeking */
787     if(s->last_picture.data[0] || s->low_delay)
788         *data_size = sizeof(AVFrame);
789 #ifdef PRINT_FRAME_TIME
790 printf("%Ld\n", rdtsc()-time);
791 #endif
792     return get_consumed_bytes(s, buf_size);
793 }
794
795 AVCodec mpeg4_decoder = {
796     "mpeg4",
797     CODEC_TYPE_VIDEO,
798     CODEC_ID_MPEG4,
799     sizeof(MpegEncContext),
800     ff_h263_decode_init,
801     NULL,
802     ff_h263_decode_end,
803     ff_h263_decode_frame,
804     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
805 };
806
807 AVCodec h263_decoder = {
808     "h263",
809     CODEC_TYPE_VIDEO,
810     CODEC_ID_H263,
811     sizeof(MpegEncContext),
812     ff_h263_decode_init,
813     NULL,
814     ff_h263_decode_end,
815     ff_h263_decode_frame,
816     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
817 };
818
819 AVCodec msmpeg4v1_decoder = {
820     "msmpeg4v1",
821     CODEC_TYPE_VIDEO,
822     CODEC_ID_MSMPEG4V1,
823     sizeof(MpegEncContext),
824     ff_h263_decode_init,
825     NULL,
826     ff_h263_decode_end,
827     ff_h263_decode_frame,
828     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
829 };
830
831 AVCodec msmpeg4v2_decoder = {
832     "msmpeg4v2",
833     CODEC_TYPE_VIDEO,
834     CODEC_ID_MSMPEG4V2,
835     sizeof(MpegEncContext),
836     ff_h263_decode_init,
837     NULL,
838     ff_h263_decode_end,
839     ff_h263_decode_frame,
840     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
841 };
842
843 AVCodec msmpeg4v3_decoder = {
844     "msmpeg4",
845     CODEC_TYPE_VIDEO,
846     CODEC_ID_MSMPEG4V3,
847     sizeof(MpegEncContext),
848     ff_h263_decode_init,
849     NULL,
850     ff_h263_decode_end,
851     ff_h263_decode_frame,
852     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
853 };
854
855 AVCodec wmv1_decoder = {
856     "wmv1",
857     CODEC_TYPE_VIDEO,
858     CODEC_ID_WMV1,
859     sizeof(MpegEncContext),
860     ff_h263_decode_init,
861     NULL,
862     ff_h263_decode_end,
863     ff_h263_decode_frame,
864     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
865 };
866
867 AVCodec h263i_decoder = {
868     "h263i",
869     CODEC_TYPE_VIDEO,
870     CODEC_ID_H263I,
871     sizeof(MpegEncContext),
872     ff_h263_decode_init,
873     NULL,
874     ff_h263_decode_end,
875     ff_h263_decode_frame,
876     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
877 };
878