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 //#define DEBUG
  24 //#define PRINT_FRAME_TIME
  25 #ifdef PRINT_FRAME_TIME
  26 static inline long long rdtsc()
  27 {
  28         long long l;
  29         asm volatile(   "rdtsc\n\t"
  30                 : "=A" (l)
  31         );
  32 //      printf("%d\n", int(l/1000));
  33         return l;
  34 }
  35 #endif
  36
  37 int ff_h263_decode_init(AVCodecContext *avctx)
  38 {
  39     MpegEncContext *s = avctx->priv_data;
  40
  41     s->avctx = avctx;
  42     s->out_format = FMT_H263;
  43
  44     s->width = avctx->width;
  45     s->height = avctx->height;
  46     s->workaround_bugs= avctx->workaround_bugs;
  47
  48     // set defaults
  49     s->quant_precision=5;
  50     s->progressive_sequence=1;
  51     s->decode_mb= ff_h263_decode_mb;
  52     s->low_delay= 1;
  53     avctx->pix_fmt= PIX_FMT_YUV420P;
  54
  55     /* select sub codec */
  56     switch(avctx->codec->id) {
  57     case CODEC_ID_H263:
  58         s->gob_number = 0;
  59         break;
  60     case CODEC_ID_MPEG4:
  61         s->time_increment_bits = 4; /* default value for broken headers */
  62         s->h263_pred = 1;
  63         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
  64         break;
  65     case CODEC_ID_MSMPEG4V1:
  66         s->h263_msmpeg4 = 1;
  67         s->h263_pred = 1;
  68         s->msmpeg4_version=1;
  69         break;
  70     case CODEC_ID_MSMPEG4V2:
  71         s->h263_msmpeg4 = 1;
  72         s->h263_pred = 1;
  73         s->msmpeg4_version=2;
  74         break;
  75     case CODEC_ID_MSMPEG4V3:
  76         s->h263_msmpeg4 = 1;
  77         s->h263_pred = 1;
  78         s->msmpeg4_version=3;
  79         break;
  80     case CODEC_ID_WMV1:
  81         s->h263_msmpeg4 = 1;
  82         s->h263_pred = 1;
  83         s->msmpeg4_version=4;
  84         break;
  85     case CODEC_ID_WMV2:
  86         s->h263_msmpeg4 = 1;
  87         s->h263_pred = 1;
  88         s->msmpeg4_version=5;
  89         break;
  90     case CODEC_ID_H263I:
  91         s->h263_intel = 1;
  92         break;
  93     default:
  94         return -1;
  95     }
  96     s->codec_id= avctx->codec->id;
  97
  98     /* for h263, we allocate the images after having read the header */
  99     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
 100         if (MPV_common_init(s) < 0)
 101             return -1;
 102
 103     if (s->h263_msmpeg4)
 104         ff_msmpeg4_decode_init(s);
 105     else
 106         h263_decode_init_vlc(s);
 107
 108     return 0;
 109 }
 110
 111 int ff_h263_decode_end(AVCodecContext *avctx)
 112 {
 113     MpegEncContext *s = avctx->priv_data;
 114
 115     MPV_common_end(s);
 116     return 0;
 117 }
 118
 119 /**
 120  * retunrs the number of bytes consumed for building the current frame
 121  */
 122 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
 123     int pos= (get_bits_count(&s->gb)+7)>>3;
 124
 125     if(s->divx_version>=500){
 126         //we would have to scan through the whole buf to handle the weird reordering ...
 127         return buf_size;
 128     }else if(s->flags&CODEC_FLAG_TRUNCATED){
 129         pos -= s->parse_context.last_index;
 130         if(pos<0) pos=0; // padding is not really read so this might be -1
 131         return pos;
 132     }else{
 133         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
 134         if(pos+10>buf_size) pos=buf_size; // oops ;)
 135
 136         return pos;
 137     }
 138 }
 139
 140 static int decode_slice(MpegEncContext *s){
 141     s->last_resync_gb= s->gb;
 142     s->first_slice_line= 1;
 143
 144     s->resync_mb_x= s->mb_x;
 145     s->resync_mb_y= s->mb_y;
 146
 147     s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
 148     s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
 149
 150     if(s->partitioned_frame){
 151         const int qscale= s->qscale;
 152
 153         if(s->codec_id==CODEC_ID_MPEG4){
 154             if(ff_mpeg4_decode_partitions(s) < 0)
 155                 return -1;
 156         }
 157
 158         /* restore variables which where modified */
 159         s->first_slice_line=1;
 160         s->mb_x= s->resync_mb_x;
 161         s->mb_y= s->resync_mb_y;
 162         s->qscale= qscale;
 163         s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
 164         s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
 165     }
 166
 167     for(; s->mb_y < s->mb_height; s->mb_y++) {
 168         /* per-row end of slice checks */
 169         if(s->msmpeg4_version){
 170             if(s->resync_mb_y + s->slice_height == s->mb_y){
 171                 const int xy= s->mb_x + s->mb_y*s->mb_width;
 172                 s->error_status_table[xy-1]|= AC_END|DC_END|MV_END;
 173                 return 0;
 174             }
 175         }
 176
 177         if(s->msmpeg4_version==1){
 178             s->last_dc[0]=
 179             s->last_dc[1]=
 180             s->last_dc[2]= 128;
 181         }
 182
 183         ff_init_block_index(s);
 184         for(; s->mb_x < s->mb_width; s->mb_x++) {
 185             int ret;
 186
 187             ff_update_block_index(s);
 188
 189             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
 190                 s->first_slice_line=0;
 191             }
 192
 193             /* DCT & quantize */
 194             s->dsp.clear_blocks(s->block[0]);
 195
 196             s->mv_dir = MV_DIR_FORWARD;
 197             s->mv_type = MV_TYPE_16X16;
 198 //            s->mb_skiped = 0;
 199 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 200             ret= s->decode_mb(s, s->block);
 201
 202             MPV_decode_mb(s, s->block);
 203
 204             if(ret<0){
 205                 const int xy= s->mb_x + s->mb_y*s->mb_width;
 206                 if(ret==SLICE_END){
 207 //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));
 208                     s->error_status_table[xy]|= AC_END;
 209                     if(!s->partitioned_frame)
 210                         s->error_status_table[xy]|= MV_END|DC_END;
 211
 212                     s->padding_bug_score--;
 213
 214                     if(++s->mb_x >= s->mb_width){
 215                         s->mb_x=0;
 216                         ff_draw_horiz_band(s);
 217                         s->mb_y++;
 218                     }
 219                     return 0;
 220                 }else if(ret==SLICE_NOEND){
 221                     fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
 222                     return -1;
 223                 }
 224                 fprintf(stderr,"Error at MB: %d\n", xy);
 225                 s->error_status_table[xy]|= AC_ERROR;
 226                 if(!s->partitioned_frame)
 227                     s->error_status_table[xy]|= DC_ERROR|MV_ERROR;
 228
 229                 return -1;
 230             }
 231         }
 232
 233         ff_draw_horiz_band(s);
 234
 235         s->mb_x= 0;
 236     }
 237
 238     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 239
 240     /* try to detect the padding bug */
 241     if(      s->codec_id==CODEC_ID_MPEG4
 242        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 243        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 244        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 245 //       &&   !s->resync_marker
 246        &&   !s->data_partitioning){
 247
 248         const int bits_count= get_bits_count(&s->gb);
 249         const int bits_left = s->gb.size_in_bits - bits_count;
 250
 251         if(bits_left==0){
 252             s->padding_bug_score+=16;
 253         }else if(bits_left>8){
 254             s->padding_bug_score++;
 255         } else if(bits_left != 1){
 256             int v= show_bits(&s->gb, 8);
 257             v|= 0x7F >> (7-(bits_count&7));
 258
 259             if(v==0x7F)
 260                 s->padding_bug_score--;
 261             else
 262                 s->padding_bug_score++;
 263         }
 264     }
 265
 266     // handle formats which dont have unique end markers
 267     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 268         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
 269         int max_extra=7;
 270
 271         /* no markers in M$ crap */
 272         if(s->msmpeg4_version && s->pict_type==I_TYPE)
 273             max_extra+= 17;
 274
 275         /* buggy padding but the frame should still end approximately at the bitstream end */
 276         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
 277             max_extra+= 48;
 278         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 279             max_extra+= 256*256*256*64;
 280
 281         if(left>max_extra){
 282             fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 283         }
 284         else if(left<0){
 285             fprintf(stderr, "overreading %d bits\n", -left);
 286         }else
 287             s->error_status_table[s->mb_num-1]|= AC_END|MV_END|DC_END;
 288
 289         return 0;
 290     }
 291
 292     fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n",
 293             s->gb.size_in_bits - get_bits_count(&s->gb),
 294             show_bits(&s->gb, 24));
 295     return -1;
 296 }
 297
 298 /**
 299  * finds the end of the current frame in the bitstream.
 300  * @return the position of the first byte of the next frame, or -1
 301  */
 302 static int mpeg4_find_frame_end(MpegEncContext *s, UINT8 *buf, int buf_size){
 303     ParseContext *pc= &s->parse_context;
 304     int vop_found, i;
 305     uint32_t state;
 306
 307     vop_found= pc->frame_start_found;
 308     state= pc->state;
 309
 310     i=0;
 311     if(!vop_found){
 312         for(i=0; i<buf_size; i++){
 313             state= (state<<8) | buf[i];
 314             if(state == 0x1B6){
 315                 i++;
 316                 vop_found=1;
 317                 break;
 318             }
 319         }
 320     }
 321
 322     for(; i<buf_size; i++){
 323         state= (state<<8) | buf[i];
 324         if((state&0xFFFFFF00) == 0x100){
 325             pc->frame_start_found=0;
 326             pc->state=-1;
 327             return i-3;
 328         }
 329     }
 330     pc->frame_start_found= vop_found;
 331     pc->state= state;
 332     return -1;
 333 }
 334
 335 static void draw_line(uint8_t *buf, int sx, int sy, int ex, int ey, int w, int h, int stride, int color){
 336     int t, x, y, f;
 337
 338     ex= clip(ex, 0, w-1);
 339     ey= clip(ey, 0, h-1);
 340
 341     buf[sy*stride + sx]+= color;
 342
 343     if(ABS(ex - sx) > ABS(ey - sy)){
 344         if(sx > ex){
 345             t=sx; sx=ex; ex=t;
 346             t=sy; sy=ey; ey=t;
 347         }
 348         buf+= sx + sy*stride;
 349         ex-= sx;
 350         f= ((ey-sy)<<16)/ex;
 351         for(x= 0; x <= ex; x++){
 352             y= ((x*f) + (1<<15))>>16;
 353             buf[y*stride + x]+= color;
 354         }
 355     }else{
 356         if(sy > ey){
 357             t=sx; sx=ex; ex=t;
 358             t=sy; sy=ey; ey=t;
 359         }
 360         buf+= sx + sy*stride;
 361         ey-= sy;
 362         if(ey) f= ((ex-sx)<<16)/ey;
 363         else   f= 0;
 364         for(y= 0; y <= ey; y++){
 365             x= ((y*f) + (1<<15))>>16;
 366             buf[y*stride + x]+= color;
 367         }
 368     }
 369 }
 370
 371 static void draw_arrow(uint8_t *buf, int sx, int sy, int ex, int ey, int w, int h, int stride, int color){
 372     int dx= ex - sx;
 373     int dy= ey - sy;
 374
 375     if(dx*dx + dy*dy > 3*3){
 376         int rx=  dx + dy;
 377         int ry= -dx + dy;
 378         int length= ff_sqrt((rx*rx + ry*ry)<<8);
 379
 380         //FIXME subpixel accuracy
 381         rx= ROUNDED_DIV(rx*3<<4, length);
 382         ry= ROUNDED_DIV(ry*3<<4, length);
 383
 384         draw_line(buf, sx, sy, sx + rx, sy + ry, w, h, stride, color);
 385         draw_line(buf, sx, sy, sx - ry, sy + rx, w, h, stride, color);
 386     }
 387     draw_line(buf, sx, sy, ex, ey, w, h, stride, color);
 388 }
 389
 390 int ff_h263_decode_frame(AVCodecContext *avctx,
 391                              void *data, int *data_size,
 392                              UINT8 *buf, int buf_size)
 393 {
 394     MpegEncContext *s = avctx->priv_data;
 395     int ret,i;
 396     AVFrame *pict = data;
 397     float new_aspect;
 398
 399 #ifdef PRINT_FRAME_TIME
 400 uint64_t time= rdtsc();
 401 #endif
 402 #ifdef DEBUG
 403     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
 404     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 405 #endif
 406     s->flags= avctx->flags;
 407
 408     *data_size = 0;
 409
 410    /* no supplementary picture */
 411     if (buf_size == 0) {
 412         return 0;
 413     }
 414
 415     if(s->flags&CODEC_FLAG_TRUNCATED){
 416         int next;
 417
 418         if(s->codec_id==CODEC_ID_MPEG4){
 419             next= mpeg4_find_frame_end(s, buf, buf_size);
 420         }else{
 421             fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
 422             return -1;
 423         }
 424
 425         if( ff_combine_frame(s, next, &buf, &buf_size) < 0 )
 426             return buf_size;
 427     }
 428
 429 retry:
 430
 431     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
 432         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 433     }else
 434         init_get_bits(&s->gb, buf, buf_size*8);
 435     s->bitstream_buffer_size=0;
 436
 437     if (!s->context_initialized) {
 438         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 439             return -1;
 440     }
 441
 442     /* let's go :-) */
 443     if (s->msmpeg4_version==5) {
 444         ret= ff_wmv2_decode_picture_header(s);
 445     } else if (s->msmpeg4_version) {
 446         ret = msmpeg4_decode_picture_header(s);
 447     } else if (s->h263_pred) {
 448         if(s->avctx->extradata_size && s->picture_number==0){
 449             GetBitContext gb;
 450
 451             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 452             ret = ff_mpeg4_decode_picture_header(s, &gb);
 453         }
 454         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 455
 456         if(s->flags& CODEC_FLAG_LOW_DELAY)
 457             s->low_delay=1;
 458     } else if (s->h263_intel) {
 459         ret = intel_h263_decode_picture_header(s);
 460     } else {
 461         ret = h263_decode_picture_header(s);
 462     }
 463     avctx->has_b_frames= !s->low_delay;
 464
 465     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 466         if(s->padding_bug_score > -2 && !s->data_partitioning)
 467             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 468         else
 469             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 470
 471         if(s->avctx->fourcc == ff_get_fourcc("XVIX"))
 472             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 473 #if 0
 474         if(s->avctx->fourcc == ff_get_fourcc("MP4S"))
 475             s->workaround_bugs|= FF_BUG_AC_VLC;
 476
 477         if(s->avctx->fourcc == ff_get_fourcc("M4S2"))
 478             s->workaround_bugs|= FF_BUG_AC_VLC;
 479 #endif
 480         if(s->avctx->fourcc == ff_get_fourcc("UMP4")){
 481             s->workaround_bugs|= FF_BUG_UMP4;
 482             s->workaround_bugs|= FF_BUG_AC_VLC;
 483         }
 484
 485         if(s->divx_version){
 486             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 487         }
 488
 489         if(s->divx_version>502){
 490             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 491         }
 492
 493         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
 494             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 495
 496         if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
 497             s->padding_bug_score= 256*256*256*64;
 498
 499         if(s->xvid_build && s->xvid_build<=3)
 500             s->padding_bug_score= 256*256*256*64;
 501
 502         if(s->xvid_build && s->xvid_build<=1)
 503             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 504
 505 #define SET_QPEL_FUNC(postfix1, postfix2) \
 506     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 507     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 508     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 509
 510         if(s->lavc_build && s->lavc_build<4653)
 511             s->workaround_bugs|= FF_BUG_STD_QPEL;
 512
 513 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 514 #if 0
 515         if(s->divx_version==500)
 516             s->workaround_bugs|= FF_BUG_NO_PADDING;
 517
 518         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 519          * lets hope this at least works
 520          */
 521         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 522            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 523             s->workaround_bugs|= FF_BUG_NO_PADDING;
 524
 525         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 526             s->workaround_bugs|= FF_BUG_NO_PADDING;
 527 #endif
 528     }
 529
 530     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 531         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 532         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 533         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 534         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 535         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 536         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 537
 538         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 539         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 540         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 541         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 542         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 543         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 544     }
 545
 546 #if 0 // dump bits per frame / qp / complexity
 547 {
 548     static FILE *f=NULL;
 549     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 550     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 551 }
 552 #endif
 553
 554         /* After H263 & mpeg4 header decode we have the height, width,*/
 555         /* and other parameters. So then we could init the picture   */
 556         /* FIXME: By the way H263 decoder is evolving it should have */
 557         /* an H263EncContext                                         */
 558     if(s->aspected_height)
 559         new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
 560     else
 561         new_aspect=0;
 562
 563     if (   s->width != avctx->width || s->height != avctx->height
 564         || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
 565         /* H.263 could change picture size any time */
 566         MPV_common_end(s);
 567         s->context_initialized=0;
 568     }
 569     if (!s->context_initialized) {
 570         avctx->width = s->width;
 571         avctx->height = s->height;
 572         avctx->aspect_ratio= new_aspect;
 573
 574         goto retry;
 575     }
 576
 577     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
 578         s->gob_index = ff_h263_get_gob_height(s);
 579
 580     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
 581     /* skip if the header was thrashed */
 582     if (ret < 0){
 583         fprintf(stderr, "header damaged\n");
 584         return -1;
 585     }
 586
 587     // for hurry_up==5
 588     s->current_picture.pict_type= s->pict_type;
 589     s->current_picture.key_frame= s->pict_type == I_TYPE;
 590
 591     /* skip b frames if we dont have reference frames */
 592     if(s->last_picture.data[0]==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 593     /* skip b frames if we are in a hurry */
 594     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 595     /* skip everything if we are in a hurry>=5 */
 596     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 597
 598     if(s->next_p_frame_damaged){
 599         if(s->pict_type==B_TYPE)
 600             return get_consumed_bytes(s, buf_size);
 601         else
 602             s->next_p_frame_damaged=0;
 603     }
 604
 605     if(MPV_frame_start(s, avctx) < 0)
 606         return -1;
 607
 608 #ifdef DEBUG
 609     printf("qscale=%d\n", s->qscale);
 610 #endif
 611
 612     if(s->error_resilience)
 613         memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(UINT8));
 614
 615     /* decode each macroblock */
 616     s->block_wrap[0]=
 617     s->block_wrap[1]=
 618     s->block_wrap[2]=
 619     s->block_wrap[3]= s->mb_width*2 + 2;
 620     s->block_wrap[4]=
 621     s->block_wrap[5]= s->mb_width + 2;
 622     s->mb_x=0;
 623     s->mb_y=0;
 624
 625     decode_slice(s);
 626     s->error_status_table[0]|= VP_START;
 627     while(s->mb_y<s->mb_height && s->gb.size_in_bits - get_bits_count(&s->gb)>16){
 628         if(s->msmpeg4_version){
 629             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
 630                 break;
 631         }else{
 632             if(ff_h263_resync(s)<0)
 633                 break;
 634         }
 635
 636         if(s->msmpeg4_version<4 && s->h263_pred)
 637             ff_mpeg4_clean_buffers(s);
 638
 639         decode_slice(s);
 640
 641         s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
 642     }
 643
 644     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 645         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 646             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 647         }
 648
 649     /* divx 5.01+ bistream reorder stuff */
 650     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
 651         int current_pos= get_bits_count(&s->gb)>>3;
 652
 653         if(   buf_size - current_pos > 5
 654            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
 655             int i;
 656             int startcode_found=0;
 657             for(i=current_pos; i<buf_size-3; i++){
 658                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 659                     startcode_found=1;
 660                     break;
 661                 }
 662             }
 663             if(startcode_found){
 664                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 665                 s->bitstream_buffer_size= buf_size - current_pos;
 666             }
 667         }
 668     }
 669
 670     if(s->error_resilience){
 671         int error=0, num_end_markers=0;
 672         for(i=0; i<s->mb_num; i++){
 673             int status= s->error_status_table[i];
 674 #if 0
 675             if(i%s->mb_width == 0) printf("\n");
 676             printf("%2X ", status);
 677 #endif
 678             if(status==0) continue;
 679
 680             if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
 681                 error=1;
 682             if(status&VP_START){
 683                 if(num_end_markers)
 684                     error=1;
 685                 num_end_markers=3;
 686             }
 687             if(status&AC_END)
 688                 num_end_markers--;
 689             if(status&DC_END)
 690                 num_end_markers--;
 691             if(status&MV_END)
 692                 num_end_markers--;
 693         }
 694         if(num_end_markers || error){
 695             fprintf(stderr, "concealing errors\n");
 696             ff_error_resilience(s);
 697         }
 698     }
 699
 700     MPV_frame_end(s);
 701
 702     if((avctx->debug&FF_DEBUG_VIS_MV) && s->last_picture.data[0]){
 703         const int shift= 1 + s->quarter_sample;
 704         int mb_y;
 705         uint8_t *ptr= s->last_picture.data[0];
 706         s->low_delay=0; //needed to see the vectors without trashing the buffers
 707
 708         for(mb_y=0; mb_y<s->mb_height; mb_y++){
 709             int mb_x;
 710             for(mb_x=0; mb_x<s->mb_width; mb_x++){
 711                 const int mb_index= mb_x + mb_y*s->mb_width;
 712                 if(s->co_located_type_table[mb_index] == MV_TYPE_8X8){
 713                     int i;
 714                     for(i=0; i<4; i++){
 715                         int sx= mb_x*16 + 4 + 8*(i&1);
 716                         int sy= mb_y*16 + 4 + 8*(i>>1);
 717                         int xy= 1 + mb_x*2 + (i&1) + (mb_y*2 + 1 + (i>>1))*(s->mb_width*2 + 2);
 718                         int mx= (s->motion_val[xy][0]>>shift) + sx;
 719                         int my= (s->motion_val[xy][1]>>shift) + sy;
 720                         draw_arrow(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
 721                     }
 722                 }else{
 723                     int sx= mb_x*16 + 8;
 724                     int sy= mb_y*16 + 8;
 725                     int xy= 1 + mb_x*2 + (mb_y*2 + 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_arrow(ptr, sx, sy, mx, my, s->width, s->height, s->linesize, 100);
 729                 }
 730                 s->mbskip_table[mb_index]=0;
 731             }
 732         }
 733     }
 734
 735
 736     if(s->pict_type==B_TYPE || s->low_delay){
 737         *pict= *(AVFrame*)&s->current_picture;
 738     } else {
 739         *pict= *(AVFrame*)&s->last_picture;
 740     }
 741
 742     if(avctx->debug&FF_DEBUG_QP){
 743         int8_t *qtab= pict->qscale_table;
 744         int x,y;
 745
 746         for(y=0; y<s->mb_height; y++){
 747             for(x=0; x<s->mb_width; x++){
 748                 printf("%2d ", qtab[x + y*s->mb_width]);
 749             }
 750             printf("\n");
 751         }
 752         printf("\n");
 753     }
 754
 755     /* Return the Picture timestamp as the frame number */
 756     /* we substract 1 because it is added on utils.c    */
 757     avctx->frame_number = s->picture_number - 1;
 758
 759     /* dont output the last pic after seeking */
 760     if(s->last_picture.data[0] || s->low_delay)
 761         *data_size = sizeof(AVFrame);
 762 #ifdef PRINT_FRAME_TIME
 763 printf("%Ld\n", rdtsc()-time);
 764 #endif
 765     return get_consumed_bytes(s, buf_size);
 766 }
 767
 768 AVCodec mpeg4_decoder = {
 769     "mpeg4",
 770     CODEC_TYPE_VIDEO,
 771     CODEC_ID_MPEG4,
 772     sizeof(MpegEncContext),
 773     ff_h263_decode_init,
 774     NULL,
 775     ff_h263_decode_end,
 776     ff_h263_decode_frame,
 777     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 778 };
 779
 780 AVCodec h263_decoder = {
 781     "h263",
 782     CODEC_TYPE_VIDEO,
 783     CODEC_ID_H263,
 784     sizeof(MpegEncContext),
 785     ff_h263_decode_init,
 786     NULL,
 787     ff_h263_decode_end,
 788     ff_h263_decode_frame,
 789     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 790 };
 791
 792 AVCodec msmpeg4v1_decoder = {
 793     "msmpeg4v1",
 794     CODEC_TYPE_VIDEO,
 795     CODEC_ID_MSMPEG4V1,
 796     sizeof(MpegEncContext),
 797     ff_h263_decode_init,
 798     NULL,
 799     ff_h263_decode_end,
 800     ff_h263_decode_frame,
 801     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 802 };
 803
 804 AVCodec msmpeg4v2_decoder = {
 805     "msmpeg4v2",
 806     CODEC_TYPE_VIDEO,
 807     CODEC_ID_MSMPEG4V2,
 808     sizeof(MpegEncContext),
 809     ff_h263_decode_init,
 810     NULL,
 811     ff_h263_decode_end,
 812     ff_h263_decode_frame,
 813     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 814 };
 815
 816 AVCodec msmpeg4v3_decoder = {
 817     "msmpeg4",
 818     CODEC_TYPE_VIDEO,
 819     CODEC_ID_MSMPEG4V3,
 820     sizeof(MpegEncContext),
 821     ff_h263_decode_init,
 822     NULL,
 823     ff_h263_decode_end,
 824     ff_h263_decode_frame,
 825     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 826 };
 827
 828 AVCodec wmv1_decoder = {
 829     "wmv1",
 830     CODEC_TYPE_VIDEO,
 831     CODEC_ID_WMV1,
 832     sizeof(MpegEncContext),
 833     ff_h263_decode_init,
 834     NULL,
 835     ff_h263_decode_end,
 836     ff_h263_decode_frame,
 837     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 838 };
 839
 840 AVCodec h263i_decoder = {
 841     "h263i",
 842     CODEC_TYPE_VIDEO,
 843     CODEC_ID_H263I,
 844     sizeof(MpegEncContext),
 845     ff_h263_decode_init,
 846     NULL,
 847     ff_h263_decode_end,
 848     ff_h263_decode_frame,
 849     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 850 };
 851