libavcodec/h263dec.c

   1 /*
   2  * H.263 decoder
   3  * Copyright (c) 2001 Fabrice Bellard.
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file h263dec.c
  23  * H.263 decoder.
  24  */
  25
  26 #include "avcodec.h"
  27 #include "dsputil.h"
  28 #include "mpegvideo.h"
  29
  30 //#define DEBUG
  31 //#define PRINT_FRAME_TIME
  32
  33 int ff_h263_decode_init(AVCodecContext *avctx)
  34 {
  35     MpegEncContext *s = avctx->priv_data;
  36
  37     s->avctx = avctx;
  38     s->out_format = FMT_H263;
  39
  40     s->width  = avctx->coded_width;
  41     s->height = avctx->coded_height;
  42     s->workaround_bugs= avctx->workaround_bugs;
  43
  44     // set defaults
  45     MPV_decode_defaults(s);
  46     s->quant_precision=5;
  47     s->decode_mb= ff_h263_decode_mb;
  48     s->low_delay= 1;
  49     avctx->pix_fmt= PIX_FMT_YUV420P;
  50     s->unrestricted_mv= 1;
  51
  52     /* select sub codec */
  53     switch(avctx->codec->id) {
  54     case CODEC_ID_H263:
  55         s->unrestricted_mv= 0;
  56         break;
  57     case CODEC_ID_MPEG4:
  58         s->decode_mb= ff_mpeg4_decode_mb;
  59         s->time_increment_bits = 4; /* default value for broken headers */
  60         s->h263_pred = 1;
  61         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
  62         break;
  63     case CODEC_ID_MSMPEG4V1:
  64         s->h263_msmpeg4 = 1;
  65         s->h263_pred = 1;
  66         s->msmpeg4_version=1;
  67         break;
  68     case CODEC_ID_MSMPEG4V2:
  69         s->h263_msmpeg4 = 1;
  70         s->h263_pred = 1;
  71         s->msmpeg4_version=2;
  72         break;
  73     case CODEC_ID_MSMPEG4V3:
  74         s->h263_msmpeg4 = 1;
  75         s->h263_pred = 1;
  76         s->msmpeg4_version=3;
  77         break;
  78     case CODEC_ID_WMV1:
  79         s->h263_msmpeg4 = 1;
  80         s->h263_pred = 1;
  81         s->msmpeg4_version=4;
  82         break;
  83     case CODEC_ID_WMV2:
  84         s->h263_msmpeg4 = 1;
  85         s->h263_pred = 1;
  86         s->msmpeg4_version=5;
  87         break;
  88     case CODEC_ID_VC1:
  89     case CODEC_ID_WMV3:
  90         s->h263_msmpeg4 = 1;
  91         s->h263_pred = 1;
  92         s->msmpeg4_version=6;
  93         break;
  94     case CODEC_ID_H263I:
  95         break;
  96     case CODEC_ID_FLV1:
  97         s->h263_flv = 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  * returns 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_packed){
 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     const int part_mask= s->partitioned_frame ? (AC_END|AC_ERROR) : 0x7F;
 148     const int mb_size= 16>>s->avctx->lowres;
 149     s->last_resync_gb= s->gb;
 150     s->first_slice_line= 1;
 151
 152     s->resync_mb_x= s->mb_x;
 153     s->resync_mb_y= s->mb_y;
 154
 155     ff_set_qscale(s, s->qscale);
 156
 157     if(s->partitioned_frame){
 158         const int qscale= s->qscale;
 159
 160         if(s->codec_id==CODEC_ID_MPEG4){
 161             if(ff_mpeg4_decode_partitions(s) < 0)
 162                 return -1;
 163         }
 164
 165         /* restore variables which were modified */
 166         s->first_slice_line=1;
 167         s->mb_x= s->resync_mb_x;
 168         s->mb_y= s->resync_mb_y;
 169         ff_set_qscale(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                 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);
 177
 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
 200             s->mv_dir = MV_DIR_FORWARD;
 201             s->mv_type = MV_TYPE_16X16;
 202 //            s->mb_skipped = 0;
 203 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 204             ret= s->decode_mb(s, s->block);
 205
 206             if (s->pict_type!=B_TYPE)
 207                 ff_h263_update_motion_val(s);
 208
 209             if(ret<0){
 210                 const int xy= s->mb_x + s->mb_y*s->mb_stride;
 211                 if(ret==SLICE_END){
 212                     MPV_decode_mb(s, s->block);
 213                     if(s->loop_filter)
 214                         ff_h263_loop_filter(s);
 215
 216 //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));
 217                     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);
 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, s->mb_y*mb_size, mb_size);
 224                         s->mb_y++;
 225                     }
 226                     return 0;
 227                 }else if(ret==SLICE_NOEND){
 228                     av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
 229                     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);
 230                     return -1;
 231                 }
 232                 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
 233                 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);
 234
 235                 return -1;
 236             }
 237
 238             MPV_decode_mb(s, s->block);
 239             if(s->loop_filter)
 240                 ff_h263_loop_filter(s);
 241         }
 242
 243         ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
 244
 245         s->mb_x= 0;
 246     }
 247
 248     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 249
 250     /* try to detect the padding bug */
 251     if(      s->codec_id==CODEC_ID_MPEG4
 252        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 253        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 254        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 255 //       &&   !s->resync_marker
 256        &&   !s->data_partitioning){
 257
 258         const int bits_count= get_bits_count(&s->gb);
 259         const int bits_left = s->gb.size_in_bits - bits_count;
 260
 261         if(bits_left==0){
 262             s->padding_bug_score+=16;
 263         } else if(bits_left != 1){
 264             int v= show_bits(&s->gb, 8);
 265             v|= 0x7F >> (7-(bits_count&7));
 266
 267             if(v==0x7F && bits_left<=8)
 268                 s->padding_bug_score--;
 269             else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
 270                 s->padding_bug_score+= 4;
 271             else
 272                 s->padding_bug_score++;
 273         }
 274     }
 275
 276     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 277         if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version || !s->resync_marker)*/)
 278             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 279         else
 280             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 281     }
 282
 283     // handle formats which don't have unique end markers
 284     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 285         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
 286         int max_extra=7;
 287
 288         /* no markers in M$ crap */
 289         if(s->msmpeg4_version && s->pict_type==I_TYPE)
 290             max_extra+= 17;
 291
 292         /* buggy padding but the frame should still end approximately at the bitstream end */
 293         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
 294             max_extra+= 48;
 295         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 296             max_extra+= 256*256*256*64;
 297
 298         if(left>max_extra){
 299             av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 300         }
 301         else if(left<0){
 302             av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
 303         }else
 304             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);
 305
 306         return 0;
 307     }
 308
 309     av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
 310             s->gb.size_in_bits - get_bits_count(&s->gb),
 311             show_bits(&s->gb, 24), s->padding_bug_score);
 312
 313     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);
 314
 315     return -1;
 316 }
 317
 318 /**
 319  * finds the end of the current frame in the bitstream.
 320  * @return the position of the first byte of the next frame, or -1
 321  */
 322 int ff_mpeg4_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){
 323     int vop_found, i;
 324     uint32_t state;
 325
 326     vop_found= pc->frame_start_found;
 327     state= pc->state;
 328
 329     i=0;
 330     if(!vop_found){
 331         for(i=0; i<buf_size; i++){
 332             state= (state<<8) | buf[i];
 333             if(state == 0x1B6){
 334                 i++;
 335                 vop_found=1;
 336                 break;
 337             }
 338         }
 339     }
 340
 341     if(vop_found){
 342         /* EOF considered as end of frame */
 343         if (buf_size == 0)
 344             return 0;
 345         for(; i<buf_size; i++){
 346             state= (state<<8) | buf[i];
 347             if((state&0xFFFFFF00) == 0x100){
 348                 pc->frame_start_found=0;
 349                 pc->state=-1;
 350                 return i-3;
 351             }
 352         }
 353     }
 354     pc->frame_start_found= vop_found;
 355     pc->state= state;
 356     return END_NOT_FOUND;
 357 }
 358
 359 static int h263_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){
 360     int vop_found, i;
 361     uint32_t state;
 362
 363     vop_found= pc->frame_start_found;
 364     state= pc->state;
 365
 366     i=0;
 367     if(!vop_found){
 368         for(i=0; i<buf_size; i++){
 369             state= (state<<8) | buf[i];
 370             if(state>>(32-22) == 0x20){
 371                 i++;
 372                 vop_found=1;
 373                 break;
 374             }
 375         }
 376     }
 377
 378     if(vop_found){
 379       for(; i<buf_size; i++){
 380         state= (state<<8) | buf[i];
 381         if(state>>(32-22) == 0x20){
 382             pc->frame_start_found=0;
 383             pc->state=-1;
 384             return i-3;
 385         }
 386       }
 387     }
 388     pc->frame_start_found= vop_found;
 389     pc->state= state;
 390
 391     return END_NOT_FOUND;
 392 }
 393
 394 #ifdef CONFIG_H263_PARSER
 395 static int h263_parse(AVCodecParserContext *s,
 396                            AVCodecContext *avctx,
 397                            uint8_t **poutbuf, int *poutbuf_size,
 398                            const uint8_t *buf, int buf_size)
 399 {
 400     ParseContext *pc = s->priv_data;
 401     int next;
 402
 403     next= h263_find_frame_end(pc, buf, buf_size);
 404
 405     if (ff_combine_frame(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
 406         *poutbuf = NULL;
 407         *poutbuf_size = 0;
 408         return buf_size;
 409     }
 410
 411     *poutbuf = (uint8_t *)buf;
 412     *poutbuf_size = buf_size;
 413     return next;
 414 }
 415 #endif
 416
 417 int ff_h263_decode_frame(AVCodecContext *avctx,
 418                              void *data, int *data_size,
 419                              uint8_t *buf, int buf_size)
 420 {
 421     MpegEncContext *s = avctx->priv_data;
 422     int ret;
 423     AVFrame *pict = data;
 424
 425 #ifdef PRINT_FRAME_TIME
 426 uint64_t time= rdtsc();
 427 #endif
 428 #ifdef DEBUG
 429     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
 430     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 431 #endif
 432     s->flags= avctx->flags;
 433     s->flags2= avctx->flags2;
 434
 435     /* no supplementary picture */
 436     if (buf_size == 0) {
 437         /* special case for last picture */
 438         if (s->low_delay==0 && s->next_picture_ptr) {
 439             *pict= *(AVFrame*)s->next_picture_ptr;
 440             s->next_picture_ptr= NULL;
 441
 442             *data_size = sizeof(AVFrame);
 443         }
 444
 445         return 0;
 446     }
 447
 448     if(s->flags&CODEC_FLAG_TRUNCATED){
 449         int next;
 450
 451         if(s->codec_id==CODEC_ID_MPEG4){
 452             next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
 453         }else if(s->codec_id==CODEC_ID_H263){
 454             next= h263_find_frame_end(&s->parse_context, buf, buf_size);
 455         }else{
 456             av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
 457             return -1;
 458         }
 459
 460         if( ff_combine_frame(&s->parse_context, next, &buf, &buf_size) < 0 )
 461             return buf_size;
 462     }
 463
 464
 465 retry:
 466
 467     if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
 468         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 469     }else
 470         init_get_bits(&s->gb, buf, buf_size*8);
 471     s->bitstream_buffer_size=0;
 472
 473     if (!s->context_initialized) {
 474         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 475             return -1;
 476     }
 477
 478     //we need to set current_picture_ptr before reading the header, otherwise we cant store anyting im there
 479     if(s->current_picture_ptr==NULL || s->current_picture_ptr->data[0]){
 480         int i= ff_find_unused_picture(s, 0);
 481         s->current_picture_ptr= &s->picture[i];
 482     }
 483
 484     /* let's go :-) */
 485     if (s->msmpeg4_version==5) {
 486         ret= ff_wmv2_decode_picture_header(s);
 487     } else if (s->msmpeg4_version) {
 488         ret = msmpeg4_decode_picture_header(s);
 489     } else if (s->h263_pred) {
 490         if(s->avctx->extradata_size && s->picture_number==0){
 491             GetBitContext gb;
 492
 493             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 494             ret = ff_mpeg4_decode_picture_header(s, &gb);
 495         }
 496         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 497
 498         if(s->flags& CODEC_FLAG_LOW_DELAY)
 499             s->low_delay=1;
 500     } else if (s->codec_id == CODEC_ID_H263I) {
 501         ret = intel_h263_decode_picture_header(s);
 502     } else if (s->h263_flv) {
 503         ret = flv_h263_decode_picture_header(s);
 504     } else {
 505         ret = h263_decode_picture_header(s);
 506     }
 507
 508     if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
 509
 510     /* skip if the header was thrashed */
 511     if (ret < 0){
 512         av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
 513         return -1;
 514     }
 515
 516     avctx->has_b_frames= !s->low_delay;
 517
 518     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 519         if(s->avctx->stream_codec_tag == ff_get_fourcc("XVID") ||
 520            s->avctx->codec_tag == ff_get_fourcc("XVID") || s->avctx->codec_tag == ff_get_fourcc("XVIX") ||
 521            s->avctx->codec_tag == ff_get_fourcc("RMP4"))
 522             s->xvid_build= -1;
 523 #if 0
 524         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
 525            && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
 526             s->xvid_build= -1;
 527 #endif
 528     }
 529
 530     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 531         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
 532             s->divx_version= 400; //divx 4
 533     }
 534
 535     if(s->xvid_build && s->divx_version){
 536         s->divx_version=
 537         s->divx_build= 0;
 538     }
 539
 540     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 541         if(s->avctx->codec_tag == ff_get_fourcc("XVIX"))
 542             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 543
 544         if(s->avctx->codec_tag == ff_get_fourcc("UMP4")){
 545             s->workaround_bugs|= FF_BUG_UMP4;
 546         }
 547
 548         if(s->divx_version>=500){
 549             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 550         }
 551
 552         if(s->divx_version>502){
 553             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 554         }
 555
 556         if(s->xvid_build && s->xvid_build<=3)
 557             s->padding_bug_score= 256*256*256*64;
 558
 559         if(s->xvid_build && s->xvid_build<=1)
 560             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 561
 562         if(s->xvid_build && s->xvid_build<=12)
 563             s->workaround_bugs|= FF_BUG_EDGE;
 564
 565         if(s->xvid_build && s->xvid_build<=32)
 566             s->workaround_bugs|= FF_BUG_DC_CLIP;
 567
 568 #define SET_QPEL_FUNC(postfix1, postfix2) \
 569     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 570     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 571     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 572
 573         if(s->lavc_build && s->lavc_build<4653)
 574             s->workaround_bugs|= FF_BUG_STD_QPEL;
 575
 576         if(s->lavc_build && s->lavc_build<4655)
 577             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 578
 579         if(s->lavc_build && s->lavc_build<4670){
 580             s->workaround_bugs|= FF_BUG_EDGE;
 581         }
 582
 583         if(s->lavc_build && s->lavc_build<=4712)
 584             s->workaround_bugs|= FF_BUG_DC_CLIP;
 585
 586         if(s->divx_version)
 587             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 588 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 589         if(s->divx_version==501 && s->divx_build==20020416)
 590             s->padding_bug_score= 256*256*256*64;
 591
 592         if(s->divx_version && s->divx_version<500){
 593             s->workaround_bugs|= FF_BUG_EDGE;
 594         }
 595
 596         if(s->divx_version)
 597             s->workaround_bugs|= FF_BUG_HPEL_CHROMA;
 598 #if 0
 599         if(s->divx_version==500)
 600             s->padding_bug_score= 256*256*256*64;
 601
 602         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 603          * lets hope this at least works
 604          */
 605         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 606            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 607             s->workaround_bugs|= FF_BUG_NO_PADDING;
 608
 609         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 610             s->workaround_bugs|= FF_BUG_NO_PADDING;
 611 #endif
 612     }
 613
 614     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 615         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 616         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 617         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 618         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 619         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 620         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 621
 622         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 623         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 624         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 625         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 626         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 627         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 628     }
 629
 630     if(avctx->debug & FF_DEBUG_BUGS)
 631         av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
 632                s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
 633                s->divx_packed ? "p" : "");
 634
 635 #if 0 // dump bits per frame / qp / complexity
 636 {
 637     static FILE *f=NULL;
 638     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 639     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 640 }
 641 #endif
 642
 643 #if defined(HAVE_MMX) && defined(CONFIG_GPL)
 644     if(s->codec_id == CODEC_ID_MPEG4 && s->xvid_build && avctx->idct_algo == FF_IDCT_AUTO && (mm_flags & MM_MMX)){
 645         avctx->idct_algo= FF_IDCT_XVIDMMX;
 646         avctx->coded_width= 0; // force reinit
 647 //        dsputil_init(&s->dsp, avctx);
 648         s->picture_number=0;
 649     }
 650 #endif
 651
 652         /* After H263 & mpeg4 header decode we have the height, width,*/
 653         /* and other parameters. So then we could init the picture   */
 654         /* FIXME: By the way H263 decoder is evolving it should have */
 655         /* an H263EncContext                                         */
 656
 657     if (   s->width  != avctx->coded_width
 658         || s->height != avctx->coded_height) {
 659         /* H.263 could change picture size any time */
 660         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 661         s->parse_context.buffer=0;
 662         MPV_common_end(s);
 663         s->parse_context= pc;
 664     }
 665     if (!s->context_initialized) {
 666         avcodec_set_dimensions(avctx, s->width, s->height);
 667
 668         goto retry;
 669     }
 670
 671     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
 672         s->gob_index = ff_h263_get_gob_height(s);
 673
 674     // for hurry_up==5
 675     s->current_picture.pict_type= s->pict_type;
 676     s->current_picture.key_frame= s->pict_type == I_TYPE;
 677
 678     /* skip B-frames if we don't have reference frames */
 679     if(s->last_picture_ptr==NULL && (s->pict_type==B_TYPE || s->dropable)) return get_consumed_bytes(s, buf_size);
 680     /* skip b frames if we are in a hurry */
 681     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 682     if(   (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==B_TYPE)
 683        || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=I_TYPE)
 684        ||  avctx->skip_frame >= AVDISCARD_ALL)
 685         return get_consumed_bytes(s, buf_size);
 686     /* skip everything if we are in a hurry>=5 */
 687     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 688
 689     if(s->next_p_frame_damaged){
 690         if(s->pict_type==B_TYPE)
 691             return get_consumed_bytes(s, buf_size);
 692         else
 693             s->next_p_frame_damaged=0;
 694     }
 695
 696     if(MPV_frame_start(s, avctx) < 0)
 697         return -1;
 698
 699 #ifdef DEBUG
 700     av_log(avctx, AV_LOG_DEBUG, "qscale=%d\n", s->qscale);
 701 #endif
 702
 703     ff_er_frame_start(s);
 704
 705     //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
 706     //which isnt available before MPV_frame_start()
 707     if (s->msmpeg4_version==5){
 708         if(ff_wmv2_decode_secondary_picture_header(s) < 0)
 709             return -1;
 710     }
 711
 712     /* decode each macroblock */
 713     s->mb_x=0;
 714     s->mb_y=0;
 715
 716     decode_slice(s);
 717     while(s->mb_y<s->mb_height){
 718         if(s->msmpeg4_version){
 719             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
 720                 break;
 721         }else{
 722             if(ff_h263_resync(s)<0)
 723                 break;
 724         }
 725
 726         if(s->msmpeg4_version<4 && s->h263_pred)
 727             ff_mpeg4_clean_buffers(s);
 728
 729         decode_slice(s);
 730     }
 731
 732     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 733         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 734             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 735         }
 736
 737     /* divx 5.01+ bistream reorder stuff */
 738     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
 739         int current_pos= get_bits_count(&s->gb)>>3;
 740         int startcode_found=0;
 741
 742         if(buf_size - current_pos > 5){
 743             int i;
 744             for(i=current_pos; i<buf_size-3; i++){
 745                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 746                     startcode_found=1;
 747                     break;
 748                 }
 749             }
 750         }
 751         if(s->gb.buffer == s->bitstream_buffer && buf_size>20){ //xvid style
 752             startcode_found=1;
 753             current_pos=0;
 754         }
 755
 756         if(startcode_found){
 757             s->bitstream_buffer= av_fast_realloc(
 758                 s->bitstream_buffer,
 759                 &s->allocated_bitstream_buffer_size,
 760                 buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
 761             memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 762             s->bitstream_buffer_size= buf_size - current_pos;
 763         }
 764     }
 765
 766     ff_er_frame_end(s);
 767
 768     MPV_frame_end(s);
 769
 770 assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
 771 assert(s->current_picture.pict_type == s->pict_type);
 772     if (s->pict_type == B_TYPE || s->low_delay) {
 773         *pict= *(AVFrame*)s->current_picture_ptr;
 774     } else if (s->last_picture_ptr != NULL) {
 775         *pict= *(AVFrame*)s->last_picture_ptr;
 776     }
 777
 778     if(s->last_picture_ptr || s->low_delay){
 779         *data_size = sizeof(AVFrame);
 780         ff_print_debug_info(s, pict);
 781     }
 782
 783     /* Return the Picture timestamp as the frame number */
 784     /* we substract 1 because it is added on utils.c    */
 785     avctx->frame_number = s->picture_number - 1;
 786
 787 #ifdef PRINT_FRAME_TIME
 788 av_log(avctx, AV_LOG_DEBUG, "%Ld\n", rdtsc()-time);
 789 #endif
 790
 791     return get_consumed_bytes(s, buf_size);
 792 }
 793
 794 AVCodec mpeg4_decoder = {
 795     "mpeg4",
 796     CODEC_TYPE_VIDEO,
 797     CODEC_ID_MPEG4,
 798     sizeof(MpegEncContext),
 799     ff_h263_decode_init,
 800     NULL,
 801     ff_h263_decode_end,
 802     ff_h263_decode_frame,
 803     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 804     .flush= ff_mpeg_flush,
 805 };
 806
 807 AVCodec h263_decoder = {
 808     "h263",
 809     CODEC_TYPE_VIDEO,
 810     CODEC_ID_H263,
 811     sizeof(MpegEncContext),
 812     ff_h263_decode_init,
 813     NULL,
 814     ff_h263_decode_end,
 815     ff_h263_decode_frame,
 816     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 817     .flush= ff_mpeg_flush,
 818 };
 819
 820 AVCodec msmpeg4v1_decoder = {
 821     "msmpeg4v1",
 822     CODEC_TYPE_VIDEO,
 823     CODEC_ID_MSMPEG4V1,
 824     sizeof(MpegEncContext),
 825     ff_h263_decode_init,
 826     NULL,
 827     ff_h263_decode_end,
 828     ff_h263_decode_frame,
 829     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 830 };
 831
 832 AVCodec msmpeg4v2_decoder = {
 833     "msmpeg4v2",
 834     CODEC_TYPE_VIDEO,
 835     CODEC_ID_MSMPEG4V2,
 836     sizeof(MpegEncContext),
 837     ff_h263_decode_init,
 838     NULL,
 839     ff_h263_decode_end,
 840     ff_h263_decode_frame,
 841     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 842 };
 843
 844 AVCodec msmpeg4v3_decoder = {
 845     "msmpeg4",
 846     CODEC_TYPE_VIDEO,
 847     CODEC_ID_MSMPEG4V3,
 848     sizeof(MpegEncContext),
 849     ff_h263_decode_init,
 850     NULL,
 851     ff_h263_decode_end,
 852     ff_h263_decode_frame,
 853     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 854 };
 855
 856 AVCodec wmv1_decoder = {
 857     "wmv1",
 858     CODEC_TYPE_VIDEO,
 859     CODEC_ID_WMV1,
 860     sizeof(MpegEncContext),
 861     ff_h263_decode_init,
 862     NULL,
 863     ff_h263_decode_end,
 864     ff_h263_decode_frame,
 865     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 866 };
 867
 868 AVCodec h263i_decoder = {
 869     "h263i",
 870     CODEC_TYPE_VIDEO,
 871     CODEC_ID_H263I,
 872     sizeof(MpegEncContext),
 873     ff_h263_decode_init,
 874     NULL,
 875     ff_h263_decode_end,
 876     ff_h263_decode_frame,
 877     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 878 };
 879
 880 AVCodec flv_decoder = {
 881     "flv",
 882     CODEC_TYPE_VIDEO,
 883     CODEC_ID_FLV1,
 884     sizeof(MpegEncContext),
 885     ff_h263_decode_init,
 886     NULL,
 887     ff_h263_decode_end,
 888     ff_h263_decode_frame,
 889     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1
 890 };
 891
 892 #ifdef CONFIG_H263_PARSER
 893 AVCodecParser h263_parser = {
 894     { CODEC_ID_H263 },
 895     sizeof(ParseContext),
 896     NULL,
 897     h263_parse,
 898     ff_parse_close,
 899 };
 900 #endif