git.sesse.net Git - ffmpeg/blob - 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     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             PRINT_QP("%2d", s->qscale);
 209             MPV_decode_mb(s, s->block);
 210
 211             if(ret<0){
 212                 const int xy= s->mb_x + s->mb_y*s->mb_width;
 213                 if(ret==SLICE_END){
 214 //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));
 215                     s->error_status_table[xy]|= AC_END;
 216                     if(!s->partitioned_frame)
 217                         s->error_status_table[xy]|= MV_END|DC_END;
 218
 219                     s->padding_bug_score--;
 220
 221                     if(++s->mb_x >= s->mb_width){
 222                         s->mb_x=0;
 223                         ff_draw_horiz_band(s);
 224                         s->mb_y++;
 225                     }
 226                     return 0;
 227                 }else if(ret==SLICE_NOEND){
 228                     fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
 229                     return -1;
 230                 }
 231                 fprintf(stderr,"Error at MB: %d\n", xy);
 232                 s->error_status_table[xy]|= AC_ERROR;
 233                 if(!s->partitioned_frame)
 234                     s->error_status_table[xy]|= DC_ERROR|MV_ERROR;
 235
 236                 return -1;
 237             }
 238         }
 239
 240         ff_draw_horiz_band(s);
 241
 242         PRINT_QP("%s", "\n");
 243
 244         s->mb_x= 0;
 245     }
 246
 247     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 248
 249     /* try to detect the padding bug */
 250     if(      s->codec_id==CODEC_ID_MPEG4
 251        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 252        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 253        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 254 //       &&   !s->resync_marker
 255        &&   !s->data_partitioning){
 256
 257         const int bits_count= get_bits_count(&s->gb);
 258         const int bits_left = s->gb.size_in_bits - bits_count;
 259
 260         if(bits_left==0){
 261             s->padding_bug_score+=16;
 262         }else if(bits_left>8){
 263             s->padding_bug_score++;
 264         } else if(bits_left != 1){
 265             int v= show_bits(&s->gb, 8);
 266             v|= 0x7F >> (7-(bits_count&7));
 267
 268             if(v==0x7F)
 269                 s->padding_bug_score--;
 270             else
 271                 s->padding_bug_score++;
 272         }
 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_in_bits - 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_in_bits - 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 void draw_line(uint8_t *buf, int sx, int sy, int ex, int ey, int w, int h, int stride, int color){
 345     int t, x, y, f;
 346
 347     ex= clip(ex, 0, w-1);
 348     ey= clip(ey, 0, h-1);
 349
 350     buf[sy*stride + sx]+= color;
 351
 352     if(ABS(ex - sx) > ABS(ey - sy)){
 353         if(sx > ex){
 354             t=sx; sx=ex; ex=t;
 355             t=sy; sy=ey; ey=t;
 356         }
 357         buf+= sx + sy*stride;
 358         ex-= sx;
 359         f= ((ey-sy)<<16)/ex;
 360         for(x= 0; x <= ex; x++){
 361             y= ((x*f) + (1<<15))>>16;
 362             buf[y*stride + x]+= color;
 363         }
 364     }else{
 365         if(sy > ey){
 366             t=sx; sx=ex; ex=t;
 367             t=sy; sy=ey; ey=t;
 368         }
 369         buf+= sx + sy*stride;
 370         ey-= sy;
 371         if(ey) f= ((ex-sx)<<16)/ey;
 372         else   f= 0;
 373         for(y= 0; y <= ey; y++){
 374             x= ((y*f) + (1<<15))>>16;
 375             buf[y*stride + x]+= color;
 376         }
 377     }
 378 }
 379
 380 int ff_h263_decode_frame(AVCodecContext *avctx,
 381                              void *data, int *data_size,
 382                              UINT8 *buf, int buf_size)
 383 {
 384     MpegEncContext *s = avctx->priv_data;
 385     int ret,i;
 386     AVFrame *pict = data;
 387     float new_aspect;
 388
 389 #ifdef PRINT_FRAME_TIME
 390 uint64_t time= rdtsc();
 391 #endif
 392 #ifdef DEBUG
 393     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
 394     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 395 #endif
 396     s->flags= avctx->flags;
 397
 398     *data_size = 0;
 399
 400    /* no supplementary picture */
 401     if (buf_size == 0) {
 402         return 0;
 403     }
 404
 405     if(s->flags&CODEC_FLAG_TRUNCATED){
 406         int next;
 407         ParseContext *pc= &s->parse_context;
 408
 409         pc->last_index= pc->index;
 410
 411         if(s->codec_id==CODEC_ID_MPEG4){
 412             next= mpeg4_find_frame_end(s, buf, buf_size);
 413         }else{
 414             fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
 415             return -1;
 416         }
 417         if(next==-1){
 418             if(buf_size + FF_INPUT_BUFFER_PADDING_SIZE + pc->index > pc->buffer_size){
 419                 pc->buffer_size= buf_size + pc->index + 10*1024;
 420                 pc->buffer= realloc(pc->buffer, pc->buffer_size);
 421             }
 422
 423             memcpy(&pc->buffer[pc->index], buf, buf_size);
 424             pc->index += buf_size;
 425             return buf_size;
 426         }
 427
 428         if(pc->index){
 429             if(next + FF_INPUT_BUFFER_PADDING_SIZE + pc->index > pc->buffer_size){
 430                 pc->buffer_size= next + pc->index + 10*1024;
 431                 pc->buffer= realloc(pc->buffer, pc->buffer_size);
 432             }
 433
 434             memcpy(&pc->buffer[pc->index], buf, next + FF_INPUT_BUFFER_PADDING_SIZE );
 435             pc->index = 0;
 436             buf= pc->buffer;
 437             buf_size= pc->last_index + next;
 438         }
 439     }
 440
 441 retry:
 442
 443     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
 444         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 445     }else
 446         init_get_bits(&s->gb, buf, buf_size*8);
 447     s->bitstream_buffer_size=0;
 448
 449     if (!s->context_initialized) {
 450         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 451             return -1;
 452     }
 453
 454     /* let's go :-) */
 455     if (s->msmpeg4_version==5) {
 456         ret= ff_wmv2_decode_picture_header(s);
 457     } else if (s->msmpeg4_version) {
 458         ret = msmpeg4_decode_picture_header(s);
 459     } else if (s->h263_pred) {
 460         if(s->avctx->extradata_size && s->picture_number==0){
 461             GetBitContext gb;
 462
 463             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 464             ret = ff_mpeg4_decode_picture_header(s, &gb);
 465         }
 466         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 467
 468         if(s->flags& CODEC_FLAG_LOW_DELAY)
 469             s->low_delay=1;
 470     } else if (s->h263_intel) {
 471         ret = intel_h263_decode_picture_header(s);
 472     } else {
 473         ret = h263_decode_picture_header(s);
 474     }
 475     avctx->has_b_frames= !s->low_delay;
 476
 477     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 478         if(s->padding_bug_score > -2 && !s->data_partitioning)
 479             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 480         else
 481             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 482
 483         if(s->avctx->fourcc == ff_get_fourcc("XVIX"))
 484             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 485 #if 0
 486         if(s->avctx->fourcc == ff_get_fourcc("MP4S"))
 487             s->workaround_bugs|= FF_BUG_AC_VLC;
 488
 489         if(s->avctx->fourcc == ff_get_fourcc("M4S2"))
 490             s->workaround_bugs|= FF_BUG_AC_VLC;
 491 #endif
 492         if(s->avctx->fourcc == ff_get_fourcc("UMP4")){
 493             s->workaround_bugs|= FF_BUG_UMP4;
 494             s->workaround_bugs|= FF_BUG_AC_VLC;
 495         }
 496
 497         if(s->divx_version){
 498             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 499         }
 500
 501         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
 502             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 503
 504         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
 505             s->padding_bug_score= 256*256*256*64;
 506
 507         if(s->xvid_build && s->xvid_build<=3)
 508             s->padding_bug_score= 256*256*256*64;
 509
 510         if(s->xvid_build && s->xvid_build<=1)
 511             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 512
 513 #define SET_QPEL_FUNC(postfix1, postfix2) \
 514     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 515     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 516     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 517
 518         if(s->lavc_build && s->lavc_build<4653)
 519             s->workaround_bugs|= FF_BUG_STD_QPEL;
 520
 521 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 522 #if 0
 523         if(s->divx_version==500)
 524             s->workaround_bugs|= FF_BUG_NO_PADDING;
 525
 526         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 527          * lets hope this at least works
 528          */
 529         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 530            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 531             s->workaround_bugs|= FF_BUG_NO_PADDING;
 532
 533         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 534             s->workaround_bugs|= FF_BUG_NO_PADDING;
 535 #endif
 536     }
 537
 538     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 539         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 540         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 541         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 542         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 543         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 544         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 545
 546         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 547         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 548         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 549         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 550         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 551         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 552     }
 553
 554 #if 0 // dump bits per frame / qp / complexity
 555 {
 556     static FILE *f=NULL;
 557     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 558     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 559 }
 560 #endif
 561
 562         /* After H263 & mpeg4 header decode we have the height, width,*/
 563         /* and other parameters. So then we could init the picture   */
 564         /* FIXME: By the way H263 decoder is evolving it should have */
 565         /* an H263EncContext                                         */
 566     if(s->aspected_height)
 567         new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
 568     else
 569         new_aspect=0;
 570
 571     if (   s->width != avctx->width || s->height != avctx->height
 572         || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
 573         /* H.263 could change picture size any time */
 574         MPV_common_end(s);
 575         s->context_initialized=0;
 576     }
 577     if (!s->context_initialized) {
 578         avctx->width = s->width;
 579         avctx->height = s->height;
 580         avctx->aspect_ratio= new_aspect;
 581
 582         goto retry;
 583     }
 584
 585     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
 586         s->gob_index = ff_h263_get_gob_height(s);
 587
 588     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
 589     /* skip if the header was thrashed */
 590     if (ret < 0){
 591         fprintf(stderr, "header damaged\n");
 592         return -1;
 593     }
 594
 595     // for hurry_up==5
 596     s->current_picture.pict_type= s->pict_type;
 597     s->current_picture.key_frame= s->pict_type == I_TYPE;
 598
 599     /* skip b frames if we dont have reference frames */
 600     if(s->last_picture.data[0]==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 601     /* skip b frames if we are in a hurry */
 602     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 603     /* skip everything if we are in a hurry>=5 */
 604     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 605
 606     if(s->next_p_frame_damaged){
 607         if(s->pict_type==B_TYPE)
 608             return get_consumed_bytes(s, buf_size);
 609         else
 610             s->next_p_frame_damaged=0;
 611     }
 612
 613     if(MPV_frame_start(s, avctx) < 0)
 614         return -1;
 615
 616 #ifdef DEBUG
 617     printf("qscale=%d\n", s->qscale);
 618 #endif
 619
 620     if(s->error_resilience)
 621         memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(UINT8));
 622
 623     /* decode each macroblock */
 624     s->block_wrap[0]=
 625     s->block_wrap[1]=
 626     s->block_wrap[2]=
 627     s->block_wrap[3]= s->mb_width*2 + 2;
 628     s->block_wrap[4]=
 629     s->block_wrap[5]= s->mb_width + 2;
 630     s->mb_x=0;
 631     s->mb_y=0;
 632
 633     decode_slice(s);
 634     s->error_status_table[0]|= VP_START;
 635     while(s->mb_y<s->mb_height && s->gb.size_in_bits - get_bits_count(&s->gb)>16){
 636         if(s->msmpeg4_version){
 637             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
 638                 break;
 639         }else{
 640             if(ff_h263_resync(s)<0)
 641                 break;
 642         }
 643
 644         if(s->msmpeg4_version<4 && s->h263_pred)
 645             ff_mpeg4_clean_buffers(s);
 646
 647         decode_slice(s);
 648
 649         s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
 650     }
 651
 652     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 653         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 654             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 655         }
 656
 657     /* divx 5.01+ bistream reorder stuff */
 658     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
 659         int current_pos= get_bits_count(&s->gb)>>3;
 660
 661         if(   buf_size - current_pos > 5
 662            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
 663             int i;
 664             int startcode_found=0;
 665             for(i=current_pos; i<buf_size-3; i++){
 666                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 667                     startcode_found=1;
 668                     break;
 669                 }
 670             }
 671             if(startcode_found){
 672                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 673                 s->bitstream_buffer_size= buf_size - current_pos;
 674             }
 675         }
 676     }
 677
 678     if(s->error_resilience){
 679         int error=0, num_end_markers=0;
 680         for(i=0; i<s->mb_num; i++){
 681             int status= s->error_status_table[i];
 682 #if 0
 683             if(i%s->mb_width == 0) printf("\n");
 684             printf("%2X ", status);
 685 #endif
 686             if(status==0) continue;
 687
 688             if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
 689                 error=1;
 690             if(status&VP_START){
 691                 if(num_end_markers)
 692                     error=1;
 693                 num_end_markers=3;
 694             }
 695             if(status&AC_END)
 696                 num_end_markers--;
 697             if(status&DC_END)
 698                 num_end_markers--;
 699             if(status&MV_END)
 700                 num_end_markers--;
 701         }
 702         if(num_end_markers || error){
 703             fprintf(stderr, "concealing errors\n");
 704             ff_error_resilience(s);
 705         }
 706     }
 707
 708     MPV_frame_end(s);
 709
 710     if((avctx->debug&FF_DEBUG_VIS_MV) && s->last_picture.data[0]){
 711         const int shift= 1 + s->quarter_sample;
 712         int mb_y;
 713         uint8_t *ptr= s->last_picture.data[0];
 714         s->low_delay=0; //needed to see the vectors without trashing the buffers
 715
 716         for(mb_y=0; mb_y<s->mb_height; mb_y++){
 717             int mb_x;
 718             for(mb_x=0; mb_x<s->mb_width; mb_x++){
 719                 const int mb_index= mb_x + mb_y*s->mb_width;
 720                 if(s->co_located_type_table[mb_index] == MV_TYPE_8X8){
 721                     int i;
 722                     for(i=0; i<4; i++){
 723                         int sx= mb_x*16 + 4 + 8*(i&1);
 724                         int sy= mb_y*16 + 4 + 8*(i>>1);
 725                         int xy= 1 + mb_x*2 + (i&1) + (mb_y*2 + 1 + (i>>1))*(s->mb_width*2 + 2);
 726                         int mx= (s->motion_val[xy][0]>>shift) + sx;
 727                         int my= (s->motion_val[xy][1]>>shift) + sy;
 728                         draw_line(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
 729                     }
 730                 }else{
 731                     int sx= mb_x*16 + 8;
 732                     int sy= mb_y*16 + 8;
 733                     int xy= 1 + mb_x*2 + (mb_y*2 + 1)*(s->mb_width*2 + 2);
 734                     int mx= (s->motion_val[xy][0]>>shift) + sx;
 735                     int my= (s->motion_val[xy][1]>>shift) + sy;
 736                     draw_line(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
 737                 }
 738                 s->mbskip_table[mb_index]=0;
 739             }
 740         }
 741     }
 742
 743
 744     if(s->pict_type==B_TYPE || s->low_delay){
 745         *pict= *(AVFrame*)&s->current_picture;
 746     } else {
 747         *pict= *(AVFrame*)&s->last_picture;
 748     }
 749
 750     if(avctx->debug&FF_DEBUG_QP){
 751         int8_t *qtab= pict->qscale_table;
 752         int x,y;
 753
 754         for(y=0; y<s->mb_height; y++){
 755             for(x=0; x<s->mb_width; x++){
 756                 printf("%2d ", qtab[x + y*s->mb_width]);
 757             }
 758             printf("\n");
 759         }
 760         printf("\n");
 761     }
 762
 763     /* Return the Picture timestamp as the frame number */
 764     /* we substract 1 because it is added on utils.c    */
 765     avctx->frame_number = s->picture_number - 1;
 766
 767     /* dont output the last pic after seeking */
 768     if(s->last_picture.data[0] || s->low_delay)
 769         *data_size = sizeof(AVFrame);
 770 #ifdef PRINT_FRAME_TIME
 771 printf("%Ld\n", rdtsc()-time);
 772 #endif
 773     return get_consumed_bytes(s, buf_size);
 774 }
 775
 776 AVCodec mpeg4_decoder = {
 777     "mpeg4",
 778     CODEC_TYPE_VIDEO,
 779     CODEC_ID_MPEG4,
 780     sizeof(MpegEncContext),
 781     ff_h263_decode_init,
 782     NULL,
 783     ff_h263_decode_end,
 784     ff_h263_decode_frame,
 785     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 786 };
 787
 788 AVCodec h263_decoder = {
 789     "h263",
 790     CODEC_TYPE_VIDEO,
 791     CODEC_ID_H263,
 792     sizeof(MpegEncContext),
 793     ff_h263_decode_init,
 794     NULL,
 795     ff_h263_decode_end,
 796     ff_h263_decode_frame,
 797     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 798 };
 799
 800 AVCodec msmpeg4v1_decoder = {
 801     "msmpeg4v1",
 802     CODEC_TYPE_VIDEO,
 803     CODEC_ID_MSMPEG4V1,
 804     sizeof(MpegEncContext),
 805     ff_h263_decode_init,
 806     NULL,
 807     ff_h263_decode_end,
 808     ff_h263_decode_frame,
 809     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 810 };
 811
 812 AVCodec msmpeg4v2_decoder = {
 813     "msmpeg4v2",
 814     CODEC_TYPE_VIDEO,
 815     CODEC_ID_MSMPEG4V2,
 816     sizeof(MpegEncContext),
 817     ff_h263_decode_init,
 818     NULL,
 819     ff_h263_decode_end,
 820     ff_h263_decode_frame,
 821     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 822 };
 823
 824 AVCodec msmpeg4v3_decoder = {
 825     "msmpeg4",
 826     CODEC_TYPE_VIDEO,
 827     CODEC_ID_MSMPEG4V3,
 828     sizeof(MpegEncContext),
 829     ff_h263_decode_init,
 830     NULL,
 831     ff_h263_decode_end,
 832     ff_h263_decode_frame,
 833     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 834 };
 835
 836 AVCodec wmv1_decoder = {
 837     "wmv1",
 838     CODEC_TYPE_VIDEO,
 839     CODEC_ID_WMV1,
 840     sizeof(MpegEncContext),
 841     ff_h263_decode_init,
 842     NULL,
 843     ff_h263_decode_end,
 844     ff_h263_decode_frame,
 845     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 846 };
 847
 848 AVCodec h263i_decoder = {
 849     "h263i",
 850     CODEC_TYPE_VIDEO,
 851     CODEC_ID_H263I,
 852     sizeof(MpegEncContext),
 853     ff_h263_decode_init,
 854     NULL,
 855     ff_h263_decode_end,
 856     ff_h263_decode_frame,
 857     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 858 };
 859