* using DSPContext - so each codec could use its local (sub)set of CPU extension
[ffmpeg.git] / libavcodec / h263dec.c
1 /*
2  * H263 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 #include "avcodec.h"
20 #include "dsputil.h"
21 #include "mpegvideo.h"
22
23 #if 1
24 #define PRINT_QP(a, b) {}
25 #else
26 #define PRINT_QP(a, b) printf(a, b)
27 #endif
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 static int 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
59     /* select sub codec */
60     switch(avctx->codec->id) {
61     case CODEC_ID_H263:
62         s->gob_number = 0;
63         break;
64     case CODEC_ID_MPEG4:
65         s->time_increment_bits = 4; /* default value for broken headers */
66         s->h263_pred = 1;
67         s->has_b_frames = 1; //default, might be overriden in the vol header during header parsing
68         break;
69     case CODEC_ID_MSMPEG4V1:
70         s->h263_msmpeg4 = 1;
71         s->h263_pred = 1;
72         s->msmpeg4_version=1;
73         break;
74     case CODEC_ID_MSMPEG4V2:
75         s->h263_msmpeg4 = 1;
76         s->h263_pred = 1;
77         s->msmpeg4_version=2;
78         break;
79     case CODEC_ID_MSMPEG4V3:
80         s->h263_msmpeg4 = 1;
81         s->h263_pred = 1;
82         s->msmpeg4_version=3;
83         break;
84     case CODEC_ID_WMV1:
85         s->h263_msmpeg4 = 1;
86         s->h263_pred = 1;
87         s->msmpeg4_version=4;
88         break;
89     case CODEC_ID_WMV2:
90         s->h263_msmpeg4 = 1;
91         s->h263_pred = 1;
92         s->msmpeg4_version=5;
93         break;
94     case CODEC_ID_H263I:
95         s->h263_intel = 1;
96         break;
97     default:
98         return -1;
99     }
100     s->codec_id= avctx->codec->id;
101
102     /* for h263, we allocate the images after having read the header */
103     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
104         if (MPV_common_init(s) < 0)
105             return -1;
106
107     if (s->h263_msmpeg4)
108         ff_msmpeg4_decode_init(s);
109     else
110         h263_decode_init_vlc(s);
111     
112     return 0;
113 }
114
115 static int h263_decode_end(AVCodecContext *avctx)
116 {
117     MpegEncContext *s = avctx->priv_data;
118
119     MPV_common_end(s);
120     return 0;
121 }
122
123 /**
124  * retunrs the number of bytes consumed for building the current frame
125  */
126 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
127     int pos= (get_bits_count(&s->gb)+7)>>3;
128     
129     if(s->divx_version>=500){
130         //we would have to scan through the whole buf to handle the weird reordering ...
131         return buf_size; 
132     }else if(s->flags&CODEC_FLAG_TRUNCATED){
133         pos -= s->parse_context.last_index;
134         if(pos<0) pos=0; // padding is not really read so this might be -1
135         return pos;
136     }else{
137         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
138         if(pos+10>buf_size) pos=buf_size; // oops ;)
139
140         return pos;
141     }
142 }
143
144 static int decode_slice(MpegEncContext *s){
145     s->last_resync_gb= s->gb;
146     s->first_slice_line= 1;
147         
148     s->resync_mb_x= s->mb_x;
149     s->resync_mb_y= s->mb_y;
150
151     s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
152     s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
153     
154     if(s->partitioned_frame){
155         const int qscale= s->qscale;
156
157         if(s->codec_id==CODEC_ID_MPEG4){
158             if(ff_mpeg4_decode_partitions(s) < 0)
159                 return -1; 
160         }
161         
162         /* restore variables which where modified */
163         s->first_slice_line=1;
164         s->mb_x= s->resync_mb_x;
165         s->mb_y= s->resync_mb_y;
166         s->qscale= qscale;
167         s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
168         s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
169     }
170
171     for(; s->mb_y < s->mb_height; s->mb_y++) {
172         /* per-row end of slice checks */
173         if(s->msmpeg4_version){
174             if(s->resync_mb_y + s->slice_height == s->mb_y){
175                 const int xy= s->mb_x + s->mb_y*s->mb_width;
176                 s->error_status_table[xy-1]|= AC_END|DC_END|MV_END;
177                 return 0;
178             }
179         }
180         
181         if(s->msmpeg4_version==1){
182             s->last_dc[0]=
183             s->last_dc[1]=
184             s->last_dc[2]= 128;
185         }
186     
187         ff_init_block_index(s);
188         for(; s->mb_x < s->mb_width; s->mb_x++) {
189             int ret;
190
191             ff_update_block_index(s);
192
193             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
194                 s->first_slice_line=0; 
195             }
196
197             /* DCT & quantize */
198             s->dsp.clear_blocks(s->block[0]);
199             
200             s->mv_dir = MV_DIR_FORWARD;
201             s->mv_type = MV_TYPE_16X16;
202 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
203             ret= s->decode_mb(s, s->block);
204             
205             PRINT_QP("%2d", s->qscale);
206             MPV_decode_mb(s, s->block);
207
208             if(ret<0){
209                 const int xy= s->mb_x + s->mb_y*s->mb_width;
210                 if(ret==SLICE_END){
211 //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));
212                     s->error_status_table[xy]|= AC_END;
213                     if(!s->partitioned_frame)
214                         s->error_status_table[xy]|= MV_END|DC_END;
215
216                     s->padding_bug_score--;
217                         
218                     if(++s->mb_x >= s->mb_width){
219                         s->mb_x=0;
220                         ff_draw_horiz_band(s);
221                         s->mb_y++;
222                     }
223                     return 0; 
224                 }else if(ret==SLICE_NOEND){
225                     fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
226                     return -1;
227                 }
228                 fprintf(stderr,"Error at MB: %d\n", xy);
229                 s->error_status_table[xy]|= AC_ERROR;
230                 if(!s->partitioned_frame)
231                     s->error_status_table[xy]|= DC_ERROR|MV_ERROR;
232     
233                 return -1;
234             }
235         }
236         
237         ff_draw_horiz_band(s);
238         
239         PRINT_QP("%s", "\n");
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*8 - get_bits_count(&s->gb) >=0
250        &&    s->gb.size*8 - 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*8 - bits_count;
256         
257         if(bits_left==0 || bits_left>8){
258             s->padding_bug_score++;
259         } else if(bits_left != 1){
260             int v= show_bits(&s->gb, 8);
261             v|= 0x7F >> (7-(bits_count&7));
262
263             if(v==0x7F)
264                 s->padding_bug_score--;
265             else
266                 s->padding_bug_score++;            
267         }
268         
269         if(s->padding_bug_score > -2)
270             s->workaround_bugs |=  FF_BUG_NO_PADDING;
271         else
272             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
273     }
274
275     // handle formats which dont have unique end markers
276     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
277         int left= s->gb.size*8 - get_bits_count(&s->gb);
278         int max_extra=7;
279         
280         /* no markers in M$ crap */
281         if(s->msmpeg4_version && s->pict_type==I_TYPE)
282             max_extra+= 17;
283         
284         /* buggy padding but the frame should still end approximately at the bitstream end */
285         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
286             max_extra+= 48;
287         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
288             max_extra+= 256*256*256*64;
289         
290         if(left>max_extra){
291             fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
292         }
293         else if(left<0){
294             fprintf(stderr, "overreading %d bits\n", -left);
295         }else
296             s->error_status_table[s->mb_num-1]|= AC_END|MV_END|DC_END;
297         
298         return 0;
299     }
300
301     fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n", 
302             s->gb.size*8 - get_bits_count(&s->gb),
303             show_bits(&s->gb, 24));
304     return -1;
305 }
306
307 /**
308  * finds the end of the current frame in the bitstream.
309  * @return the position of the first byte of the next frame, or -1
310  */
311 static int mpeg4_find_frame_end(MpegEncContext *s, UINT8 *buf, int buf_size){
312     ParseContext *pc= &s->parse_context;
313     int vop_found, i;
314     uint32_t state;
315     
316     vop_found= pc->frame_start_found;
317     state= pc->state;
318     
319     i=0;
320     if(!vop_found){
321         for(i=0; i<buf_size; i++){
322             state= (state<<8) | buf[i];
323             if(state == 0x1B6){
324                 i++;
325                 vop_found=1;
326                 break;
327             }
328         }
329     }
330     
331     for(; i<buf_size; i++){
332         state= (state<<8) | buf[i];
333         if((state&0xFFFFFF00) == 0x100){
334             pc->frame_start_found=0;
335             pc->state=-1; 
336             return i-3;
337         }
338     }
339     pc->frame_start_found= vop_found;
340     pc->state= state;
341     return -1;
342 }
343
344 static int h263_decode_frame(AVCodecContext *avctx, 
345                              void *data, int *data_size,
346                              UINT8 *buf, int buf_size)
347 {
348     MpegEncContext *s = avctx->priv_data;
349     int ret,i;
350     AVPicture *pict = data; 
351 #ifdef PRINT_FRAME_TIME
352 uint64_t time= rdtsc();
353 #endif
354 #ifdef DEBUG
355     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
356     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
357 #endif
358
359     s->hurry_up= avctx->hurry_up;
360     s->error_resilience= avctx->error_resilience;
361
362     s->flags= avctx->flags;
363
364     *data_size = 0;
365    
366    /* no supplementary picture */
367     if (buf_size == 0) {
368         return 0;
369     }
370     
371     if(s->flags&CODEC_FLAG_TRUNCATED){
372         int next;
373         ParseContext *pc= &s->parse_context;
374         
375         pc->last_index= pc->index;
376
377         if(s->codec_id==CODEC_ID_MPEG4){
378             next= mpeg4_find_frame_end(s, buf, buf_size);
379         }else{
380             fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
381             return -1;
382         }
383         if(next==-1){
384             if(buf_size + FF_INPUT_BUFFER_PADDING_SIZE + pc->index > pc->buffer_size){
385                 pc->buffer_size= buf_size + pc->index + 10*1024;
386                 pc->buffer= realloc(pc->buffer, pc->buffer_size);
387             }
388
389             memcpy(&pc->buffer[pc->index], buf, buf_size);
390             pc->index += buf_size;
391             return buf_size;
392         }
393
394         if(pc->index){
395             if(next + FF_INPUT_BUFFER_PADDING_SIZE + pc->index > pc->buffer_size){
396                 pc->buffer_size= next + pc->index + 10*1024;
397                 pc->buffer= realloc(pc->buffer, pc->buffer_size);
398             }
399
400             memcpy(&pc->buffer[pc->index], buf, next + FF_INPUT_BUFFER_PADDING_SIZE );
401             pc->index = 0;
402             buf= pc->buffer;
403             buf_size= pc->last_index + next;
404         }
405     }
406
407 retry:
408     
409     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
410         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size);
411     }else
412         init_get_bits(&s->gb, buf, buf_size);
413     s->bitstream_buffer_size=0;
414
415     if (!s->context_initialized) {
416         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
417             return -1;
418     }
419         
420     /* let's go :-) */
421     if (s->h263_msmpeg4) {
422         ret = msmpeg4_decode_picture_header(s);
423     } else if (s->h263_pred) {
424         if(s->avctx->extradata_size && s->picture_number==0){
425             GetBitContext gb;
426             
427             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size);
428             ret = ff_mpeg4_decode_picture_header(s, &gb);
429         }
430         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
431
432         if(s->flags& CODEC_FLAG_LOW_DELAY)
433             s->low_delay=1;
434
435         s->has_b_frames= !s->low_delay;
436     } else if (s->h263_intel) {
437         ret = intel_h263_decode_picture_header(s);
438     } else {
439         ret = h263_decode_picture_header(s);
440     }
441     avctx->has_b_frames= s->has_b_frames;
442
443     if(s->workaround_bugs&FF_BUG_AUTODETECT){
444         if(s->avctx->fourcc == ff_get_fourcc("XVIX")) 
445             s->workaround_bugs|= FF_BUG_XVID_ILACE;
446
447         if(s->avctx->fourcc == ff_get_fourcc("MP4S")) 
448             s->workaround_bugs|= FF_BUG_AC_VLC;
449         
450         if(s->avctx->fourcc == ff_get_fourcc("M4S2")) 
451             s->workaround_bugs|= FF_BUG_AC_VLC;
452                 
453         if(s->avctx->fourcc == ff_get_fourcc("UMP4")){
454             s->workaround_bugs|= FF_BUG_UMP4;
455             s->workaround_bugs|= FF_BUG_AC_VLC;
456         }
457
458         if(s->divx_version){
459             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
460         }
461
462         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
463             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
464         
465         if(s->xvid_build && s->xvid_build<=1)
466             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
467
468 //printf("padding_bug_score: %d\n", s->padding_bug_score);
469 #if 0
470         if(s->divx_version==500)
471             s->workaround_bugs|= FF_BUG_NO_PADDING;
472
473         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
474          * lets hope this at least works
475          */
476         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
477            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
478             s->workaround_bugs|= FF_BUG_NO_PADDING;
479         
480         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
481             s->workaround_bugs|= FF_BUG_NO_PADDING;
482 #endif
483     }
484     
485
486 #if 0 // dump bits per frame / qp / complexity
487 {
488     static FILE *f=NULL;
489     if(!f) f=fopen("rate_qp_cplx.txt", "w");
490     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
491 }
492 #endif
493        
494         /* After H263 & mpeg4 header decode we have the height, width,*/
495         /* and other parameters. So then we could init the picture   */
496         /* FIXME: By the way H263 decoder is evolving it should have */
497         /* an H263EncContext                                         */
498     if (   s->width != avctx->width || s->height != avctx->height 
499         || avctx->aspect_ratio_info != s->aspect_ratio_info
500         || avctx->aspected_width != s->aspected_width
501         || avctx->aspected_height != s->aspected_height) {
502         /* H.263 could change picture size any time */
503         MPV_common_end(s);
504         s->context_initialized=0;
505     }
506     if (!s->context_initialized) {
507         avctx->width = s->width;
508         avctx->height = s->height;
509         avctx->aspect_ratio_info= s->aspect_ratio_info;
510         if (s->aspect_ratio_info == FF_ASPECT_EXTENDED)
511         {
512             avctx->aspected_width = s->aspected_width;
513             avctx->aspected_height = s->aspected_height;
514         }
515
516         goto retry;
517     }
518
519     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
520         s->gob_index = ff_h263_get_gob_height(s);
521
522     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
523     /* skip if the header was thrashed */
524     if (ret < 0){
525         fprintf(stderr, "header damaged\n");
526         return -1;
527     }
528     
529     s->avctx->key_frame   = (s->pict_type == I_TYPE);
530     s->avctx->pict_type   = s->pict_type;
531
532     /* skip b frames if we dont have reference frames */
533     if(s->num_available_buffers<2 && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
534     /* skip b frames if we are in a hurry */
535     if(s->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
536     /* skip everything if we are in a hurry>=5 */
537     if(s->hurry_up>=5) return get_consumed_bytes(s, buf_size);
538     
539     if(s->next_p_frame_damaged){
540         if(s->pict_type==B_TYPE)
541             return get_consumed_bytes(s, buf_size);
542         else
543             s->next_p_frame_damaged=0;
544     }
545
546     if(MPV_frame_start(s, avctx) < 0)
547         return -1;
548
549 #ifdef DEBUG
550     printf("qscale=%d\n", s->qscale);
551 #endif
552
553     if(s->error_resilience)
554         memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(UINT8));
555     
556     /* decode each macroblock */
557     s->block_wrap[0]=
558     s->block_wrap[1]=
559     s->block_wrap[2]=
560     s->block_wrap[3]= s->mb_width*2 + 2;
561     s->block_wrap[4]=
562     s->block_wrap[5]= s->mb_width + 2;
563     s->mb_x=0; 
564     s->mb_y=0;
565     
566     decode_slice(s);
567     s->error_status_table[0]|= VP_START;
568     while(s->mb_y<s->mb_height && s->gb.size*8 - get_bits_count(&s->gb)>16){
569         if(s->msmpeg4_version){
570             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
571                 break;
572         }else{
573             if(ff_h263_resync(s)<0)
574                 break;
575         }
576         
577         if(s->msmpeg4_version!=4 && s->h263_pred)
578             ff_mpeg4_clean_buffers(s);
579
580         decode_slice(s);
581
582         s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
583     }
584
585     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
586         if(msmpeg4_decode_ext_header(s, buf_size) < 0) return -1;
587     
588     /* divx 5.01+ bistream reorder stuff */
589     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
590         int current_pos= get_bits_count(&s->gb)>>3;
591
592         if(   buf_size - current_pos > 5 
593            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
594             int i;
595             int startcode_found=0;
596             for(i=current_pos; i<buf_size-3; i++){
597                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
598                     startcode_found=1;
599                     break;
600                 }
601             }
602             if(startcode_found){
603                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
604                 s->bitstream_buffer_size= buf_size - current_pos;
605             }
606         }
607     }
608
609     if(s->error_resilience){
610         int error=0, num_end_markers=0;
611         for(i=0; i<s->mb_num; i++){
612             int status= s->error_status_table[i];
613 #if 0
614             if(i%s->mb_width == 0) printf("\n");
615             printf("%2X ", status); 
616 #endif
617             if(status==0) continue;
618
619             if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
620                 error=1;
621             if(status&VP_START){
622                 if(num_end_markers) 
623                     error=1;
624                 num_end_markers=3;
625             }
626             if(status&AC_END)
627                 num_end_markers--;
628             if(status&DC_END)
629                 num_end_markers--;
630             if(status&MV_END)
631                 num_end_markers--;
632         }
633         if(num_end_markers || error){
634             fprintf(stderr, "concealing errors\n");
635 //printf("type:%d\n", s->pict_type);
636             ff_error_resilience(s);
637         }
638     }
639
640     MPV_frame_end(s);
641 #if 0 //dirty show MVs, we should export the MV tables and write a filter to show them
642 {
643   int mb_y;
644   s->has_b_frames=1;
645   for(mb_y=0; mb_y<s->mb_height; mb_y++){
646     int mb_x;
647     int y= mb_y*16 + 8;
648     for(mb_x=0; mb_x<s->mb_width; mb_x++){
649       int x= mb_x*16 + 8;
650       uint8_t *ptr= s->last_picture[0];
651       int xy= 1 + mb_x*2 + (mb_y*2 + 1)*(s->mb_width*2 + 2);
652       int mx= (s->motion_val[xy][0]>>1) + x;
653       int my= (s->motion_val[xy][1]>>1) + y;
654       int i;
655       int max;
656
657       if(mx<0) mx=0;
658       if(my<0) my=0;
659       if(mx>=s->width)  mx= s->width -1;
660       if(my>=s->height) my= s->height-1;
661       max= ABS(mx-x);
662       if(ABS(my-y) > max) max= ABS(my-y);
663       /* the ugliest linedrawing routine ... */
664       for(i=0; i<max; i++){
665         int x1= x + (mx-x)*i/max;
666         int y1= y + (my-y)*i/max;
667         ptr[y1*s->linesize + x1]+=100;
668       }
669       ptr[y*s->linesize + x]+=100;
670       s->mbskip_table[mb_x + mb_y*s->mb_width]=0;
671     }
672   }
673
674 }
675 #endif    
676     if(s->pict_type==B_TYPE || (!s->has_b_frames)){
677         pict->data[0] = s->current_picture[0];
678         pict->data[1] = s->current_picture[1];
679         pict->data[2] = s->current_picture[2];
680     } else {
681         pict->data[0] = s->last_picture[0];
682         pict->data[1] = s->last_picture[1];
683         pict->data[2] = s->last_picture[2];
684     }
685     pict->linesize[0] = s->linesize;
686     pict->linesize[1] = s->uvlinesize;
687     pict->linesize[2] = s->uvlinesize;
688
689     avctx->quality = s->qscale;
690
691     /* Return the Picture timestamp as the frame number */
692     /* we substract 1 because it is added on utils.c    */
693     avctx->frame_number = s->picture_number - 1;
694
695     /* dont output the last pic after seeking 
696        note we allready added +1 for the current pix in MPV_frame_end(s) */
697     if(s->num_available_buffers>=2 || (!s->has_b_frames))
698         *data_size = sizeof(AVPicture);
699 #ifdef PRINT_FRAME_TIME
700 printf("%Ld\n", rdtsc()-time);
701 #endif
702     return get_consumed_bytes(s, buf_size);
703 }
704
705 AVCodec mpeg4_decoder = {
706     "mpeg4",
707     CODEC_TYPE_VIDEO,
708     CODEC_ID_MPEG4,
709     sizeof(MpegEncContext),
710     h263_decode_init,
711     NULL,
712     h263_decode_end,
713     h263_decode_frame,
714     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
715 };
716
717 AVCodec h263_decoder = {
718     "h263",
719     CODEC_TYPE_VIDEO,
720     CODEC_ID_H263,
721     sizeof(MpegEncContext),
722     h263_decode_init,
723     NULL,
724     h263_decode_end,
725     h263_decode_frame,
726     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
727 };
728
729 AVCodec msmpeg4v1_decoder = {
730     "msmpeg4v1",
731     CODEC_TYPE_VIDEO,
732     CODEC_ID_MSMPEG4V1,
733     sizeof(MpegEncContext),
734     h263_decode_init,
735     NULL,
736     h263_decode_end,
737     h263_decode_frame,
738     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
739 };
740
741 AVCodec msmpeg4v2_decoder = {
742     "msmpeg4v2",
743     CODEC_TYPE_VIDEO,
744     CODEC_ID_MSMPEG4V2,
745     sizeof(MpegEncContext),
746     h263_decode_init,
747     NULL,
748     h263_decode_end,
749     h263_decode_frame,
750     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
751 };
752
753 AVCodec msmpeg4v3_decoder = {
754     "msmpeg4",
755     CODEC_TYPE_VIDEO,
756     CODEC_ID_MSMPEG4V3,
757     sizeof(MpegEncContext),
758     h263_decode_init,
759     NULL,
760     h263_decode_end,
761     h263_decode_frame,
762     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
763 };
764
765 AVCodec wmv1_decoder = {
766     "wmv1",
767     CODEC_TYPE_VIDEO,
768     CODEC_ID_WMV1,
769     sizeof(MpegEncContext),
770     h263_decode_init,
771     NULL,
772     h263_decode_end,
773     h263_decode_frame,
774     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
775 };
776
777 AVCodec wmv2_decoder = {
778     "wmv2",
779     CODEC_TYPE_VIDEO,
780     CODEC_ID_WMV2,
781     sizeof(MpegEncContext),
782     h263_decode_init,
783     NULL,
784     h263_decode_end,
785     h263_decode_frame,
786     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
787 };
788
789 AVCodec h263i_decoder = {
790     "h263i",
791     CODEC_TYPE_VIDEO,
792     CODEC_ID_H263I,
793     sizeof(MpegEncContext),
794     h263_decode_init,
795     NULL,
796     h263_decode_end,
797     h263_decode_frame,
798     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
799 };
800