libavcodec/h263dec.c

   1 /*
   2  * H.263 decoder
   3  * Copyright (c) 2001 Fabrice Bellard.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file h263dec.c
  22  * H.263 decoder.
  23  */
  24
  25 #include "avcodec.h"
  26 #include "dsputil.h"
  27 #include "mpegvideo.h"
  28
  29 //#define DEBUG
  30 //#define PRINT_FRAME_TIME
  31 #ifdef PRINT_FRAME_TIME
  32 static inline long long rdtsc()
  33 {
  34         long long l;
  35         asm volatile(   "rdtsc\n\t"
  36                 : "=A" (l)
  37         );
  38 //      printf("%d\n", int(l/1000));
  39         return l;
  40 }
  41 #endif
  42
  43 int ff_h263_decode_init(AVCodecContext *avctx)
  44 {
  45     MpegEncContext *s = avctx->priv_data;
  46
  47     s->avctx = avctx;
  48     s->out_format = FMT_H263;
  49
  50     s->width = avctx->width;
  51     s->height = avctx->height;
  52     s->workaround_bugs= avctx->workaround_bugs;
  53
  54     // set defaults
  55     s->quant_precision=5;
  56     s->progressive_sequence=1;
  57     s->decode_mb= ff_h263_decode_mb;
  58     s->low_delay= 1;
  59     avctx->pix_fmt= PIX_FMT_YUV420P;
  60     s->unrestricted_mv= 1;
  61
  62     /* select sub codec */
  63     switch(avctx->codec->id) {
  64     case CODEC_ID_H263:
  65         s->gob_number = 0;
  66         break;
  67     case CODEC_ID_MPEG4:
  68         s->time_increment_bits = 4; /* default value for broken headers */
  69         s->h263_pred = 1;
  70         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
  71         break;
  72     case CODEC_ID_MSMPEG4V1:
  73         s->h263_msmpeg4 = 1;
  74         s->h263_pred = 1;
  75         s->msmpeg4_version=1;
  76         break;
  77     case CODEC_ID_MSMPEG4V2:
  78         s->h263_msmpeg4 = 1;
  79         s->h263_pred = 1;
  80         s->msmpeg4_version=2;
  81         break;
  82     case CODEC_ID_MSMPEG4V3:
  83         s->h263_msmpeg4 = 1;
  84         s->h263_pred = 1;
  85         s->msmpeg4_version=3;
  86         break;
  87     case CODEC_ID_WMV1:
  88         s->h263_msmpeg4 = 1;
  89         s->h263_pred = 1;
  90         s->msmpeg4_version=4;
  91         break;
  92     case CODEC_ID_WMV2:
  93         s->h263_msmpeg4 = 1;
  94         s->h263_pred = 1;
  95         s->msmpeg4_version=5;
  96         break;
  97     case CODEC_ID_H263I:
  98         s->h263_intel = 1;
  99         break;
 100     case CODEC_ID_FLV1:
 101         s->h263_flv = 1;
 102         break;
 103     default:
 104         return -1;
 105     }
 106     s->codec_id= avctx->codec->id;
 107
 108     /* for h263, we allocate the images after having read the header */
 109     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
 110         if (MPV_common_init(s) < 0)
 111             return -1;
 112
 113     if (s->h263_msmpeg4)
 114         ff_msmpeg4_decode_init(s);
 115     else
 116         h263_decode_init_vlc(s);
 117
 118     return 0;
 119 }
 120
 121 int ff_h263_decode_end(AVCodecContext *avctx)
 122 {
 123     MpegEncContext *s = avctx->priv_data;
 124
 125     MPV_common_end(s);
 126     return 0;
 127 }
 128
 129 /**
 130  * retunrs the number of bytes consumed for building the current frame
 131  */
 132 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
 133     int pos= (get_bits_count(&s->gb)+7)>>3;
 134
 135     if(s->divx_packed){
 136         //we would have to scan through the whole buf to handle the weird reordering ...
 137         return buf_size;
 138     }else if(s->flags&CODEC_FLAG_TRUNCATED){
 139         pos -= s->parse_context.last_index;
 140         if(pos<0) pos=0; // padding is not really read so this might be -1
 141         return pos;
 142     }else{
 143         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
 144         if(pos+10>buf_size) pos=buf_size; // oops ;)
 145
 146         return pos;
 147     }
 148 }
 149
 150 static int decode_slice(MpegEncContext *s){
 151     const int part_mask= s->partitioned_frame ? (AC_END|AC_ERROR) : 0x7F;
 152     s->last_resync_gb= s->gb;
 153     s->first_slice_line= 1;
 154
 155     s->resync_mb_x= s->mb_x;
 156     s->resync_mb_y= s->mb_y;
 157
 158     s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
 159     s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
 160
 161     if(s->partitioned_frame){
 162         const int qscale= s->qscale;
 163
 164         if(s->codec_id==CODEC_ID_MPEG4){
 165             if(ff_mpeg4_decode_partitions(s) < 0)
 166                 return -1;
 167         }
 168
 169         /* restore variables which were modified */
 170         s->first_slice_line=1;
 171         s->mb_x= s->resync_mb_x;
 172         s->mb_y= s->resync_mb_y;
 173         s->qscale= qscale;
 174         s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
 175         s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
 176     }
 177
 178     for(; s->mb_y < s->mb_height; s->mb_y++) {
 179         /* per-row end of slice checks */
 180         if(s->msmpeg4_version){
 181             if(s->resync_mb_y + s->slice_height == s->mb_y){
 182                 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
 183
 184                 return 0;
 185             }
 186         }
 187
 188         if(s->msmpeg4_version==1){
 189             s->last_dc[0]=
 190             s->last_dc[1]=
 191             s->last_dc[2]= 128;
 192         }
 193
 194         ff_init_block_index(s);
 195         for(; s->mb_x < s->mb_width; s->mb_x++) {
 196             int ret;
 197
 198             ff_update_block_index(s);
 199
 200             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
 201                 s->first_slice_line=0;
 202             }
 203
 204             /* DCT & quantize */
 205             s->dsp.clear_blocks(s->block[0]);
 206
 207             s->mv_dir = MV_DIR_FORWARD;
 208             s->mv_type = MV_TYPE_16X16;
 209 //            s->mb_skiped = 0;
 210 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 211             ret= s->decode_mb(s, s->block);
 212
 213             if (s->pict_type!=B_TYPE)
 214                 ff_h263_update_motion_val(s);
 215
 216             if(ret<0){
 217                 const int xy= s->mb_x + s->mb_y*s->mb_stride;
 218                 if(ret==SLICE_END){
 219                     MPV_decode_mb(s, s->block);
 220
 221 //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));
 222                     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
 223
 224                     s->padding_bug_score--;
 225
 226                     if(++s->mb_x >= s->mb_width){
 227                         s->mb_x=0;
 228                         ff_draw_horiz_band(s, s->mb_y*16, 16);
 229                         s->mb_y++;
 230                     }
 231                     return 0;
 232                 }else if(ret==SLICE_NOEND){
 233                     fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
 234                     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
 235                     return -1;
 236                 }
 237                 fprintf(stderr,"Error at MB: %d\n", xy);
 238                 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);
 239
 240                 return -1;
 241             }
 242
 243             MPV_decode_mb(s, s->block);
 244         }
 245
 246         ff_draw_horiz_band(s, s->mb_y*16, 16);
 247
 248         s->mb_x= 0;
 249     }
 250
 251     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 252
 253     /* try to detect the padding bug */
 254     if(      s->codec_id==CODEC_ID_MPEG4
 255        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 256        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 257        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 258 //       &&   !s->resync_marker
 259        &&   !s->data_partitioning){
 260
 261         const int bits_count= get_bits_count(&s->gb);
 262         const int bits_left = s->gb.size_in_bits - bits_count;
 263
 264         if(bits_left==0){
 265             s->padding_bug_score+=16;
 266         }else if(bits_left>8){
 267             s->padding_bug_score++;
 268         } else if(bits_left != 1){
 269             int v= show_bits(&s->gb, 8);
 270             v|= 0x7F >> (7-(bits_count&7));
 271
 272             if(v==0x7F)
 273                 s->padding_bug_score--;
 274             else
 275                 s->padding_bug_score++;
 276         }
 277     }
 278
 279     // handle formats which dont have unique end markers
 280     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 281         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
 282         int max_extra=7;
 283
 284         /* no markers in M$ crap */
 285         if(s->msmpeg4_version && s->pict_type==I_TYPE)
 286             max_extra+= 17;
 287
 288         /* buggy padding but the frame should still end approximately at the bitstream end */
 289         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
 290             max_extra+= 48;
 291         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 292             max_extra+= 256*256*256*64;
 293
 294         if(left>max_extra){
 295             fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 296         }
 297         else if(left<0){
 298             fprintf(stderr, "overreading %d bits\n", -left);
 299         }else
 300             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
 301
 302         return 0;
 303     }
 304
 305     fprintf(stderr, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
 306             s->gb.size_in_bits - get_bits_count(&s->gb),
 307             show_bits(&s->gb, 24), s->padding_bug_score);
 308
 309     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
 310
 311     return -1;
 312 }
 313
 314 /**
 315  * finds the end of the current frame in the bitstream.
 316  * @return the position of the first byte of the next frame, or -1
 317  */
 318 static int mpeg4_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
 319     ParseContext *pc= &s->parse_context;
 320     int vop_found, i;
 321     uint32_t state;
 322
 323     vop_found= pc->frame_start_found;
 324     state= pc->state;
 325
 326     i=0;
 327     if(!vop_found){
 328         for(i=0; i<buf_size; i++){
 329             state= (state<<8) | buf[i];
 330             if(state == 0x1B6){
 331                 i++;
 332                 vop_found=1;
 333                 break;
 334             }
 335         }
 336     }
 337
 338     if(vop_found){
 339       for(; i<buf_size; i++){
 340         state= (state<<8) | buf[i];
 341         if((state&0xFFFFFF00) == 0x100){
 342             pc->frame_start_found=0;
 343             pc->state=-1;
 344             return i-3;
 345         }
 346       }
 347     }
 348     pc->frame_start_found= vop_found;
 349     pc->state= state;
 350     return END_NOT_FOUND;
 351 }
 352
 353 static int h263_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
 354     ParseContext *pc= &s->parse_context;
 355     int vop_found, i;
 356     uint32_t state;
 357
 358     vop_found= pc->frame_start_found;
 359     state= pc->state;
 360
 361     i=0;
 362     if(!vop_found){
 363         for(i=0; i<buf_size; i++){
 364             state= (state<<8) | buf[i];
 365             if(state>>(32-22) == 0x20){
 366                 i++;
 367                 vop_found=1;
 368                 break;
 369             }
 370         }
 371     }
 372
 373     if(vop_found){
 374       for(; i<buf_size; i++){
 375         state= (state<<8) | buf[i];
 376         if(state>>(32-22) == 0x20){
 377             pc->frame_start_found=0;
 378             pc->state=-1;
 379             return i-3;
 380         }
 381       }
 382     }
 383     pc->frame_start_found= vop_found;
 384     pc->state= state;
 385
 386     return END_NOT_FOUND;
 387 }
 388
 389 int ff_h263_decode_frame(AVCodecContext *avctx,
 390                              void *data, int *data_size,
 391                              uint8_t *buf, int buf_size)
 392 {
 393     MpegEncContext *s = avctx->priv_data;
 394     int ret;
 395     AVFrame *pict = data;
 396     float new_aspect;
 397
 398 #ifdef PRINT_FRAME_TIME
 399 uint64_t time= rdtsc();
 400 #endif
 401 #ifdef DEBUG
 402     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
 403     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 404 #endif
 405     s->flags= avctx->flags;
 406
 407     *data_size = 0;
 408
 409     /* no supplementary picture */
 410     if (buf_size == 0) {
 411         /* special case for last picture */
 412         if (s->low_delay==0 && s->next_picture_ptr) {
 413             *pict= *(AVFrame*)s->next_picture_ptr;
 414             s->next_picture_ptr= NULL;
 415
 416             *data_size = sizeof(AVFrame);
 417         }
 418
 419         return 0;
 420     }
 421
 422     if(s->flags&CODEC_FLAG_TRUNCATED){
 423         int next;
 424
 425         if(s->codec_id==CODEC_ID_MPEG4){
 426             next= mpeg4_find_frame_end(s, buf, buf_size);
 427         }else if(s->codec_id==CODEC_ID_H263){
 428             next= h263_find_frame_end(s, buf, buf_size);
 429         }else{
 430             fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
 431             return -1;
 432         }
 433
 434         if( ff_combine_frame(s, next, &buf, &buf_size) < 0 )
 435             return buf_size;
 436     }
 437
 438 retry:
 439
 440     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
 441         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 442     }else
 443         init_get_bits(&s->gb, buf, buf_size*8);
 444     s->bitstream_buffer_size=0;
 445
 446     if (!s->context_initialized) {
 447         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 448             return -1;
 449     }
 450
 451     /* let's go :-) */
 452     if (s->msmpeg4_version==5) {
 453         ret= ff_wmv2_decode_picture_header(s);
 454     } else if (s->msmpeg4_version) {
 455         ret = msmpeg4_decode_picture_header(s);
 456     } else if (s->h263_pred) {
 457         if(s->avctx->extradata_size && s->picture_number==0){
 458             GetBitContext gb;
 459
 460             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 461             ret = ff_mpeg4_decode_picture_header(s, &gb);
 462         }
 463         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 464
 465         if(s->flags& CODEC_FLAG_LOW_DELAY)
 466             s->low_delay=1;
 467     } else if (s->h263_intel) {
 468         ret = intel_h263_decode_picture_header(s);
 469     } else if (s->h263_flv) {
 470         ret = flv_h263_decode_picture_header(s);
 471     } else {
 472         ret = h263_decode_picture_header(s);
 473     }
 474
 475     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
 476
 477     /* skip if the header was thrashed */
 478     if (ret < 0){
 479         fprintf(stderr, "header damaged\n");
 480         return -1;
 481     }
 482
 483     avctx->has_b_frames= !s->low_delay;
 484
 485     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 486         if(s->avctx->stream_codec_tag == ff_get_fourcc("XVID") ||
 487            s->avctx->codec_tag == ff_get_fourcc("XVID") || s->avctx->codec_tag == ff_get_fourcc("XVIX"))
 488             s->xvid_build= -1;
 489 #if 0
 490         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
 491            && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
 492             s->xvid_build= -1;
 493 #endif
 494     }
 495
 496     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 497         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
 498             s->divx_version= 400; //divx 4
 499     }
 500
 501     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 502         s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 503
 504         if(s->padding_bug_score > -2 && !s->data_partitioning && (s->divx_version || !s->resync_marker))
 505             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 506
 507         if(s->avctx->codec_tag == ff_get_fourcc("XVIX"))
 508             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 509
 510         if(s->avctx->codec_tag == ff_get_fourcc("UMP4")){
 511             s->workaround_bugs|= FF_BUG_UMP4;
 512         }
 513
 514         if(s->divx_version>=500){
 515             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 516         }
 517
 518         if(s->divx_version>502){
 519             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 520         }
 521
 522         if(s->xvid_build && s->xvid_build<=3)
 523             s->padding_bug_score= 256*256*256*64;
 524
 525         if(s->xvid_build && s->xvid_build<=1)
 526             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 527
 528         if(s->xvid_build && s->xvid_build<=12)
 529             s->workaround_bugs|= FF_BUG_EDGE;
 530
 531 #define SET_QPEL_FUNC(postfix1, postfix2) \
 532     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 533     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 534     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 535
 536         if(s->lavc_build && s->lavc_build<4653)
 537             s->workaround_bugs|= FF_BUG_STD_QPEL;
 538
 539         if(s->lavc_build && s->lavc_build<4655)
 540             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 541
 542         if(s->lavc_build && s->lavc_build<4670){
 543             s->workaround_bugs|= FF_BUG_EDGE;
 544         }
 545
 546         if(s->divx_version)
 547             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 548 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 549         if(s->divx_version==501 && s->divx_build==20020416)
 550             s->padding_bug_score= 256*256*256*64;
 551
 552         if(s->divx_version && s->divx_version<500){
 553             s->workaround_bugs|= FF_BUG_EDGE;
 554         }
 555
 556 #if 0
 557         if(s->divx_version==500)
 558             s->padding_bug_score= 256*256*256*64;
 559
 560         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 561          * lets hope this at least works
 562          */
 563         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 564            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 565             s->workaround_bugs|= FF_BUG_NO_PADDING;
 566
 567         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 568             s->workaround_bugs|= FF_BUG_NO_PADDING;
 569 #endif
 570     }
 571
 572     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 573         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 574         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 575         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 576         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 577         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 578         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 579
 580         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 581         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 582         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 583         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 584         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 585         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 586     }
 587
 588     if(avctx->debug & FF_DEBUG_BUGS)
 589         printf("bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
 590                s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
 591                s->divx_packed ? "p" : "");
 592
 593 #if 0 // dump bits per frame / qp / complexity
 594 {
 595     static FILE *f=NULL;
 596     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 597     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 598 }
 599 #endif
 600
 601         /* After H263 & mpeg4 header decode we have the height, width,*/
 602         /* and other parameters. So then we could init the picture   */
 603         /* FIXME: By the way H263 decoder is evolving it should have */
 604         /* an H263EncContext                                         */
 605     if(s->aspected_height)
 606         new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
 607     else
 608         new_aspect=0;
 609
 610     if (   s->width != avctx->width || s->height != avctx->height
 611         || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
 612         /* H.263 could change picture size any time */
 613         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 614         s->parse_context.buffer=0;
 615         MPV_common_end(s);
 616         s->parse_context= pc;
 617     }
 618     if (!s->context_initialized) {
 619         avctx->width = s->width;
 620         avctx->height = s->height;
 621         avctx->aspect_ratio= new_aspect;
 622
 623         goto retry;
 624     }
 625
 626     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
 627         s->gob_index = ff_h263_get_gob_height(s);
 628
 629     // for hurry_up==5
 630     s->current_picture.pict_type= s->pict_type;
 631     s->current_picture.key_frame= s->pict_type == I_TYPE;
 632
 633     /* skip b frames if we dont have reference frames */
 634     if(s->last_picture_ptr==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 635     /* skip b frames if we are in a hurry */
 636     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 637     /* skip everything if we are in a hurry>=5 */
 638     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 639
 640     if(s->next_p_frame_damaged){
 641         if(s->pict_type==B_TYPE)
 642             return get_consumed_bytes(s, buf_size);
 643         else
 644             s->next_p_frame_damaged=0;
 645     }
 646
 647     if(MPV_frame_start(s, avctx) < 0)
 648         return -1;
 649
 650 #ifdef DEBUG
 651     printf("qscale=%d\n", s->qscale);
 652 #endif
 653
 654     ff_er_frame_start(s);
 655
 656     //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
 657     //which isnt available before MPV_frame_start()
 658     if (s->msmpeg4_version==5){
 659         if(ff_wmv2_decode_secondary_picture_header(s) < 0)
 660             return -1;
 661     }
 662
 663     /* decode each macroblock */
 664     s->mb_x=0;
 665     s->mb_y=0;
 666
 667     decode_slice(s);
 668     while(s->mb_y<s->mb_height){
 669         if(s->msmpeg4_version){
 670             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
 671                 break;
 672         }else{
 673             if(ff_h263_resync(s)<0)
 674                 break;
 675         }
 676
 677         if(s->msmpeg4_version<4 && s->h263_pred)
 678             ff_mpeg4_clean_buffers(s);
 679
 680         decode_slice(s);
 681     }
 682
 683     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 684         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 685             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 686         }
 687
 688     /* divx 5.01+ bistream reorder stuff */
 689     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
 690         int current_pos= get_bits_count(&s->gb)>>3;
 691
 692         if(   buf_size - current_pos > 5
 693            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
 694             int i;
 695             int startcode_found=0;
 696             for(i=current_pos; i<buf_size-3; i++){
 697                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 698                     startcode_found=1;
 699                     break;
 700                 }
 701             }
 702             if(startcode_found){
 703                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 704                 s->bitstream_buffer_size= buf_size - current_pos;
 705             }
 706         }
 707     }
 708
 709     ff_er_frame_end(s);
 710
 711     MPV_frame_end(s);
 712
 713 assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
 714 assert(s->current_picture.pict_type == s->pict_type);
 715     if(s->pict_type==B_TYPE || s->low_delay){
 716         *pict= *(AVFrame*)&s->current_picture;
 717         ff_print_debug_info(s, s->current_picture_ptr);
 718     } else {
 719         *pict= *(AVFrame*)&s->last_picture;
 720         ff_print_debug_info(s, s->last_picture_ptr);
 721     }
 722
 723     /* Return the Picture timestamp as the frame number */
 724     /* we substract 1 because it is added on utils.c    */
 725     avctx->frame_number = s->picture_number - 1;
 726
 727     /* dont output the last pic after seeking */
 728     if(s->last_picture_ptr || s->low_delay)
 729         *data_size = sizeof(AVFrame);
 730 #ifdef PRINT_FRAME_TIME
 731 printf("%Ld\n", rdtsc()-time);
 732 #endif
 733
 734     return get_consumed_bytes(s, buf_size);
 735 }
 736
 737 static const AVOption mpeg4_decoptions[] =
 738 {
 739     AVOPTION_SUB(avoptions_workaround_bug),
 740     AVOPTION_END()
 741 };
 742
 743 AVCodec mpeg4_decoder = {
 744     "mpeg4",
 745     CODEC_TYPE_VIDEO,
 746     CODEC_ID_MPEG4,
 747     sizeof(MpegEncContext),
 748     ff_h263_decode_init,
 749     NULL,
 750     ff_h263_decode_end,
 751     ff_h263_decode_frame,
 752     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 753     .options = mpeg4_decoptions,
 754     .flush= ff_mpeg_flush,
 755 };
 756
 757 AVCodec h263_decoder = {
 758     "h263",
 759     CODEC_TYPE_VIDEO,
 760     CODEC_ID_H263,
 761     sizeof(MpegEncContext),
 762     ff_h263_decode_init,
 763     NULL,
 764     ff_h263_decode_end,
 765     ff_h263_decode_frame,
 766     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 767     .flush= ff_mpeg_flush,
 768 };
 769
 770 AVCodec msmpeg4v1_decoder = {
 771     "msmpeg4v1",
 772     CODEC_TYPE_VIDEO,
 773     CODEC_ID_MSMPEG4V1,
 774     sizeof(MpegEncContext),
 775     ff_h263_decode_init,
 776     NULL,
 777     ff_h263_decode_end,
 778     ff_h263_decode_frame,
 779     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 780     mpeg4_decoptions,
 781 };
 782
 783 AVCodec msmpeg4v2_decoder = {
 784     "msmpeg4v2",
 785     CODEC_TYPE_VIDEO,
 786     CODEC_ID_MSMPEG4V2,
 787     sizeof(MpegEncContext),
 788     ff_h263_decode_init,
 789     NULL,
 790     ff_h263_decode_end,
 791     ff_h263_decode_frame,
 792     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 793     mpeg4_decoptions,
 794 };
 795
 796 AVCodec msmpeg4v3_decoder = {
 797     "msmpeg4",
 798     CODEC_TYPE_VIDEO,
 799     CODEC_ID_MSMPEG4V3,
 800     sizeof(MpegEncContext),
 801     ff_h263_decode_init,
 802     NULL,
 803     ff_h263_decode_end,
 804     ff_h263_decode_frame,
 805     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 806     .options = mpeg4_decoptions,
 807 };
 808
 809 AVCodec wmv1_decoder = {
 810     "wmv1",
 811     CODEC_TYPE_VIDEO,
 812     CODEC_ID_WMV1,
 813     sizeof(MpegEncContext),
 814     ff_h263_decode_init,
 815     NULL,
 816     ff_h263_decode_end,
 817     ff_h263_decode_frame,
 818     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 819     mpeg4_decoptions,
 820 };
 821
 822 AVCodec h263i_decoder = {
 823     "h263i",
 824     CODEC_TYPE_VIDEO,
 825     CODEC_ID_H263I,
 826     sizeof(MpegEncContext),
 827     ff_h263_decode_init,
 828     NULL,
 829     ff_h263_decode_end,
 830     ff_h263_decode_frame,
 831     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 832     mpeg4_decoptions,
 833 };
 834
 835 AVCodec flv_decoder = {
 836     "flv",
 837     CODEC_TYPE_VIDEO,
 838     CODEC_ID_FLV1,
 839     sizeof(MpegEncContext),
 840     ff_h263_decode_init,
 841     NULL,
 842     ff_h263_decode_end,
 843     ff_h263_decode_frame,
 844     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1
 845 };