qpel encoding
[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 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
60     /* select sub codec */
61     switch(avctx->codec->id) {
62     case CODEC_ID_H263:
63         s->gob_number = 0;
64         break;
65     case CODEC_ID_MPEG4:
66         s->time_increment_bits = 4; /* default value for broken headers */
67         s->h263_pred = 1;
68         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
69         break;
70     case CODEC_ID_MSMPEG4V1:
71         s->h263_msmpeg4 = 1;
72         s->h263_pred = 1;
73         s->msmpeg4_version=1;
74         break;
75     case CODEC_ID_MSMPEG4V2:
76         s->h263_msmpeg4 = 1;
77         s->h263_pred = 1;
78         s->msmpeg4_version=2;
79         break;
80     case CODEC_ID_MSMPEG4V3:
81         s->h263_msmpeg4 = 1;
82         s->h263_pred = 1;
83         s->msmpeg4_version=3;
84         break;
85     case CODEC_ID_WMV1:
86         s->h263_msmpeg4 = 1;
87         s->h263_pred = 1;
88         s->msmpeg4_version=4;
89         break;
90     case CODEC_ID_WMV2:
91         s->h263_msmpeg4 = 1;
92         s->h263_pred = 1;
93         s->msmpeg4_version=5;
94         break;
95     case CODEC_ID_H263I:
96         s->h263_intel = 1;
97         break;
98     default:
99         return -1;
100     }
101     s->codec_id= avctx->codec->id;
102
103     /* for h263, we allocate the images after having read the header */
104     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
105         if (MPV_common_init(s) < 0)
106             return -1;
107
108     if (s->h263_msmpeg4)
109         ff_msmpeg4_decode_init(s);
110     else
111         h263_decode_init_vlc(s);
112     
113     return 0;
114 }
115
116 int ff_h263_decode_end(AVCodecContext *avctx)
117 {
118     MpegEncContext *s = avctx->priv_data;
119
120     MPV_common_end(s);
121     return 0;
122 }
123
124 /**
125  * retunrs the number of bytes consumed for building the current frame
126  */
127 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
128     int pos= (get_bits_count(&s->gb)+7)>>3;
129     
130     if(s->divx_version>=500){
131         //we would have to scan through the whole buf to handle the weird reordering ...
132         return buf_size; 
133     }else if(s->flags&CODEC_FLAG_TRUNCATED){
134         pos -= s->parse_context.last_index;
135         if(pos<0) pos=0; // padding is not really read so this might be -1
136         return pos;
137     }else{
138         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
139         if(pos+10>buf_size) pos=buf_size; // oops ;)
140
141         return pos;
142     }
143 }
144
145 static int decode_slice(MpegEncContext *s){
146     s->last_resync_gb= s->gb;
147     s->first_slice_line= 1;
148         
149     s->resync_mb_x= s->mb_x;
150     s->resync_mb_y= s->mb_y;
151
152     s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
153     s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
154     
155     if(s->partitioned_frame){
156         const int qscale= s->qscale;
157
158         if(s->codec_id==CODEC_ID_MPEG4){
159             if(ff_mpeg4_decode_partitions(s) < 0)
160                 return -1; 
161         }
162         
163         /* restore variables which where modified */
164         s->first_slice_line=1;
165         s->mb_x= s->resync_mb_x;
166         s->mb_y= s->resync_mb_y;
167         s->qscale= qscale;
168         s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
169         s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
170     }
171
172     for(; s->mb_y < s->mb_height; s->mb_y++) {
173         /* per-row end of slice checks */
174         if(s->msmpeg4_version){
175             if(s->resync_mb_y + s->slice_height == s->mb_y){
176                 const int xy= s->mb_x + s->mb_y*s->mb_width;
177                 s->error_status_table[xy-1]|= AC_END|DC_END|MV_END;
178                 return 0;
179             }
180         }
181         
182         if(s->msmpeg4_version==1){
183             s->last_dc[0]=
184             s->last_dc[1]=
185             s->last_dc[2]= 128;
186         }
187     
188         ff_init_block_index(s);
189         for(; s->mb_x < s->mb_width; s->mb_x++) {
190             int ret;
191
192             ff_update_block_index(s);
193
194             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
195                 s->first_slice_line=0; 
196             }
197
198             /* DCT & quantize */
199             s->dsp.clear_blocks(s->block[0]);
200             
201             s->mv_dir = MV_DIR_FORWARD;
202             s->mv_type = MV_TYPE_16X16;
203 //            s->mb_skiped = 0;
204 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
205             ret= s->decode_mb(s, s->block);
206             
207             PRINT_QP("%2d", s->qscale);
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);
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);
240         
241         PRINT_QP("%s", "\n");
242         
243         s->mb_x= 0;
244     }
245     
246     assert(s->mb_x==0 && s->mb_y==s->mb_height);
247
248     /* try to detect the padding bug */
249     if(      s->codec_id==CODEC_ID_MPEG4
250        &&   (s->workaround_bugs&FF_BUG_AUTODETECT) 
251        &&    s->gb.size*8 - get_bits_count(&s->gb) >=0
252        &&    s->gb.size*8 - get_bits_count(&s->gb) < 48
253 //       &&   !s->resync_marker
254        &&   !s->data_partitioning){
255         
256         const int bits_count= get_bits_count(&s->gb);
257         const int bits_left = s->gb.size*8 - bits_count;
258         
259         if(bits_left==0 || 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         if(s->padding_bug_score > -2)
272             s->workaround_bugs |=  FF_BUG_NO_PADDING;
273         else
274             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
275     }
276
277     // handle formats which dont have unique end markers
278     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
279         int left= s->gb.size*8 - get_bits_count(&s->gb);
280         int max_extra=7;
281         
282         /* no markers in M$ crap */
283         if(s->msmpeg4_version && s->pict_type==I_TYPE)
284             max_extra+= 17;
285         
286         /* buggy padding but the frame should still end approximately at the bitstream end */
287         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
288             max_extra+= 48;
289         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
290             max_extra+= 256*256*256*64;
291         
292         if(left>max_extra){
293             fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
294         }
295         else if(left<0){
296             fprintf(stderr, "overreading %d bits\n", -left);
297         }else
298             s->error_status_table[s->mb_num-1]|= AC_END|MV_END|DC_END;
299         
300         return 0;
301     }
302
303     fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n", 
304             s->gb.size*8 - get_bits_count(&s->gb),
305             show_bits(&s->gb, 24));
306     return -1;
307 }
308
309 /**
310  * finds the end of the current frame in the bitstream.
311  * @return the position of the first byte of the next frame, or -1
312  */
313 static int mpeg4_find_frame_end(MpegEncContext *s, UINT8 *buf, int buf_size){
314     ParseContext *pc= &s->parse_context;
315     int vop_found, i;
316     uint32_t state;
317     
318     vop_found= pc->frame_start_found;
319     state= pc->state;
320     
321     i=0;
322     if(!vop_found){
323         for(i=0; i<buf_size; i++){
324             state= (state<<8) | buf[i];
325             if(state == 0x1B6){
326                 i++;
327                 vop_found=1;
328                 break;
329             }
330         }
331     }
332     
333     for(; i<buf_size; i++){
334         state= (state<<8) | buf[i];
335         if((state&0xFFFFFF00) == 0x100){
336             pc->frame_start_found=0;
337             pc->state=-1; 
338             return i-3;
339         }
340     }
341     pc->frame_start_found= vop_found;
342     pc->state= state;
343     return -1;
344 }
345
346 int ff_h263_decode_frame(AVCodecContext *avctx, 
347                              void *data, int *data_size,
348                              UINT8 *buf, int buf_size)
349 {
350     MpegEncContext *s = avctx->priv_data;
351     int ret,i;
352     AVFrame *pict = data; 
353     float new_aspect;
354     
355 #ifdef PRINT_FRAME_TIME
356 uint64_t time= rdtsc();
357 #endif
358 #ifdef DEBUG
359     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
360     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
361 #endif
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->msmpeg4_version==5) {
422         ret= ff_wmv2_decode_picture_header(s);
423     } else if (s->msmpeg4_version) {
424         ret = msmpeg4_decode_picture_header(s);
425     } else if (s->h263_pred) {
426         if(s->avctx->extradata_size && s->picture_number==0){
427             GetBitContext gb;
428             
429             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size);
430             ret = ff_mpeg4_decode_picture_header(s, &gb);
431         }
432         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
433
434         if(s->flags& CODEC_FLAG_LOW_DELAY)
435             s->low_delay=1;
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->low_delay;
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 #if 0
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 #endif
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->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
466             s->padding_bug_score= 256*256*256*64;
467         
468         if(s->xvid_build && s->xvid_build<=1)
469             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
470
471 //printf("padding_bug_score: %d\n", s->padding_bug_score);
472 #if 0
473         if(s->divx_version==500)
474             s->workaround_bugs|= FF_BUG_NO_PADDING;
475
476         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
477          * lets hope this at least works
478          */
479         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
480            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
481             s->workaround_bugs|= FF_BUG_NO_PADDING;
482         
483         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
484             s->workaround_bugs|= FF_BUG_NO_PADDING;
485 #endif
486     }
487     
488
489 #if 0 // dump bits per frame / qp / complexity
490 {
491     static FILE *f=NULL;
492     if(!f) f=fopen("rate_qp_cplx.txt", "w");
493     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
494 }
495 #endif
496        
497         /* After H263 & mpeg4 header decode we have the height, width,*/
498         /* and other parameters. So then we could init the picture   */
499         /* FIXME: By the way H263 decoder is evolving it should have */
500         /* an H263EncContext                                         */
501     if(s->aspected_height)
502         new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
503     else
504         new_aspect=0;
505     
506     if (   s->width != avctx->width || s->height != avctx->height 
507         || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
508         /* H.263 could change picture size any time */
509         MPV_common_end(s);
510         s->context_initialized=0;
511     }
512     if (!s->context_initialized) {
513         avctx->width = s->width;
514         avctx->height = s->height;
515         avctx->aspect_ratio= new_aspect;
516
517         goto retry;
518     }
519
520     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
521         s->gob_index = ff_h263_get_gob_height(s);
522
523     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
524     /* skip if the header was thrashed */
525     if (ret < 0){
526         fprintf(stderr, "header damaged\n");
527         return -1;
528     }
529     
530     // for hurry_up==5
531     s->current_picture.pict_type= s->pict_type;
532     s->current_picture.key_frame= s->pict_type == I_TYPE;
533
534     /* skip b frames if we dont have reference frames */
535     if(s->last_picture.data[0]==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
536     /* skip b frames if we are in a hurry */
537     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
538     /* skip everything if we are in a hurry>=5 */
539     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
540     
541     if(s->next_p_frame_damaged){
542         if(s->pict_type==B_TYPE)
543             return get_consumed_bytes(s, buf_size);
544         else
545             s->next_p_frame_damaged=0;
546     }
547
548     if(MPV_frame_start(s, avctx) < 0)
549         return -1;
550
551 #ifdef DEBUG
552     printf("qscale=%d\n", s->qscale);
553 #endif
554
555     if(s->error_resilience)
556         memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(UINT8));
557     
558     /* decode each macroblock */
559     s->block_wrap[0]=
560     s->block_wrap[1]=
561     s->block_wrap[2]=
562     s->block_wrap[3]= s->mb_width*2 + 2;
563     s->block_wrap[4]=
564     s->block_wrap[5]= s->mb_width + 2;
565     s->mb_x=0; 
566     s->mb_y=0;
567     
568     decode_slice(s);
569     s->error_status_table[0]|= VP_START;
570     while(s->mb_y<s->mb_height && s->gb.size*8 - get_bits_count(&s->gb)>16){
571         if(s->msmpeg4_version){
572             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
573                 break;
574         }else{
575             if(ff_h263_resync(s)<0)
576                 break;
577         }
578         
579         if(s->msmpeg4_version!=4 && s->h263_pred)
580             ff_mpeg4_clean_buffers(s);
581
582         decode_slice(s);
583
584         s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
585     }
586
587     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
588         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
589             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
590         }
591     
592     /* divx 5.01+ bistream reorder stuff */
593     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
594         int current_pos= get_bits_count(&s->gb)>>3;
595
596         if(   buf_size - current_pos > 5 
597            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
598             int i;
599             int startcode_found=0;
600             for(i=current_pos; i<buf_size-3; i++){
601                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
602                     startcode_found=1;
603                     break;
604                 }
605             }
606             if(startcode_found){
607                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
608                 s->bitstream_buffer_size= buf_size - current_pos;
609             }
610         }
611     }
612
613     if(s->error_resilience){
614         int error=0, num_end_markers=0;
615         for(i=0; i<s->mb_num; i++){
616             int status= s->error_status_table[i];
617 #if 0
618             if(i%s->mb_width == 0) printf("\n");
619             printf("%2X ", status); 
620 #endif
621             if(status==0) continue;
622
623             if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
624                 error=1;
625             if(status&VP_START){
626                 if(num_end_markers) 
627                     error=1;
628                 num_end_markers=3;
629             }
630             if(status&AC_END)
631                 num_end_markers--;
632             if(status&DC_END)
633                 num_end_markers--;
634             if(status&MV_END)
635                 num_end_markers--;
636         }
637         if(num_end_markers || error){
638             fprintf(stderr, "concealing errors\n");
639             ff_error_resilience(s);
640         }
641     }
642
643     MPV_frame_end(s);
644 #if 0 //dirty show MVs, we should export the MV tables and write a filter to show them
645 {
646   int mb_y;
647   s->has_b_frames=1;
648   for(mb_y=0; mb_y<s->mb_height; mb_y++){
649     int mb_x;
650     int y= mb_y*16 + 8;
651     for(mb_x=0; mb_x<s->mb_width; mb_x++){
652       int x= mb_x*16 + 8;
653       uint8_t *ptr= s->last_picture.data[0];
654       int xy= 1 + mb_x*2 + (mb_y*2 + 1)*(s->mb_width*2 + 2);
655       int mx= (s->motion_val[xy][0]>>1) + x;
656       int my= (s->motion_val[xy][1]>>1) + y;
657       int i;
658       int max;
659
660       if(mx<0) mx=0;
661       if(my<0) my=0;
662       if(mx>=s->width)  mx= s->width -1;
663       if(my>=s->height) my= s->height-1;
664       max= ABS(mx-x);
665       if(ABS(my-y) > max) max= ABS(my-y);
666       /* the ugliest linedrawing routine ... */
667       for(i=0; i<max; i++){
668         int x1= x + (mx-x)*i/max;
669         int y1= y + (my-y)*i/max;
670         ptr[y1*s->linesize + x1]+=100;
671       }
672       ptr[y*s->linesize + x]+=100;
673       s->mbskip_table[mb_x + mb_y*s->mb_width]=0;
674     }
675   }
676
677 }
678 #endif
679
680     if(s->pict_type==B_TYPE || s->low_delay){
681         *pict= *(AVFrame*)&s->current_picture;
682     } else {
683         *pict= *(AVFrame*)&s->last_picture;
684     }
685
686     if(avctx->debug&FF_DEBUG_QP){
687         int8_t *qtab= pict->qscale_table;
688         int x,y;
689         
690         for(y=0; y<s->mb_height; y++){
691             for(x=0; x<s->mb_width; x++){
692                 printf("%2d ", qtab[x + y*s->mb_width]);
693             }
694             printf("\n");
695         }
696         printf("\n");
697     }
698
699     /* Return the Picture timestamp as the frame number */
700     /* we substract 1 because it is added on utils.c    */
701     avctx->frame_number = s->picture_number - 1;
702
703     /* dont output the last pic after seeking */
704     if(s->last_picture.data[0] || s->low_delay)
705         *data_size = sizeof(AVFrame);
706 #ifdef PRINT_FRAME_TIME
707 printf("%Ld\n", rdtsc()-time);
708 #endif
709     return get_consumed_bytes(s, buf_size);
710 }
711
712 AVCodec mpeg4_decoder = {
713     "mpeg4",
714     CODEC_TYPE_VIDEO,
715     CODEC_ID_MPEG4,
716     sizeof(MpegEncContext),
717     ff_h263_decode_init,
718     NULL,
719     ff_h263_decode_end,
720     ff_h263_decode_frame,
721     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
722 };
723
724 AVCodec h263_decoder = {
725     "h263",
726     CODEC_TYPE_VIDEO,
727     CODEC_ID_H263,
728     sizeof(MpegEncContext),
729     ff_h263_decode_init,
730     NULL,
731     ff_h263_decode_end,
732     ff_h263_decode_frame,
733     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
734 };
735
736 AVCodec msmpeg4v1_decoder = {
737     "msmpeg4v1",
738     CODEC_TYPE_VIDEO,
739     CODEC_ID_MSMPEG4V1,
740     sizeof(MpegEncContext),
741     ff_h263_decode_init,
742     NULL,
743     ff_h263_decode_end,
744     ff_h263_decode_frame,
745     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
746 };
747
748 AVCodec msmpeg4v2_decoder = {
749     "msmpeg4v2",
750     CODEC_TYPE_VIDEO,
751     CODEC_ID_MSMPEG4V2,
752     sizeof(MpegEncContext),
753     ff_h263_decode_init,
754     NULL,
755     ff_h263_decode_end,
756     ff_h263_decode_frame,
757     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
758 };
759
760 AVCodec msmpeg4v3_decoder = {
761     "msmpeg4",
762     CODEC_TYPE_VIDEO,
763     CODEC_ID_MSMPEG4V3,
764     sizeof(MpegEncContext),
765     ff_h263_decode_init,
766     NULL,
767     ff_h263_decode_end,
768     ff_h263_decode_frame,
769     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
770 };
771
772 AVCodec wmv1_decoder = {
773     "wmv1",
774     CODEC_TYPE_VIDEO,
775     CODEC_ID_WMV1,
776     sizeof(MpegEncContext),
777     ff_h263_decode_init,
778     NULL,
779     ff_h263_decode_end,
780     ff_h263_decode_frame,
781     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
782 };
783
784 AVCodec h263i_decoder = {
785     "h263i",
786     CODEC_TYPE_VIDEO,
787     CODEC_ID_H263I,
788     sizeof(MpegEncContext),
789     ff_h263_decode_init,
790     NULL,
791     ff_h263_decode_end,
792     ff_h263_decode_frame,
793     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
794 };
795