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 file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file h263dec.c
  25  * H.263 decoder.
  26  */
  27
  28 #include "avcodec.h"
  29 #include "dsputil.h"
  30 #include "mpegvideo.h"
  31 #include "h263_parser.h"
  32 #include "mpeg4video_parser.h"
  33
  34 //#define DEBUG
  35 //#define PRINT_FRAME_TIME
  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->coded_width;
  45     s->height = avctx->coded_height;
  46     s->workaround_bugs= avctx->workaround_bugs;
  47
  48     // set defaults
  49     MPV_decode_defaults(s);
  50     s->quant_precision=5;
  51     s->decode_mb= ff_h263_decode_mb;
  52     s->low_delay= 1;
  53     avctx->pix_fmt= PIX_FMT_YUV420P;
  54     s->unrestricted_mv= 1;
  55
  56     /* select sub codec */
  57     switch(avctx->codec->id) {
  58     case CODEC_ID_H263:
  59         s->unrestricted_mv= 0;
  60         break;
  61     case CODEC_ID_MPEG4:
  62         s->decode_mb= ff_mpeg4_decode_mb;
  63         s->time_increment_bits = 4; /* default value for broken headers */
  64         s->h263_pred = 1;
  65         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
  66         break;
  67     case CODEC_ID_MSMPEG4V1:
  68         s->h263_msmpeg4 = 1;
  69         s->h263_pred = 1;
  70         s->msmpeg4_version=1;
  71         break;
  72     case CODEC_ID_MSMPEG4V2:
  73         s->h263_msmpeg4 = 1;
  74         s->h263_pred = 1;
  75         s->msmpeg4_version=2;
  76         break;
  77     case CODEC_ID_MSMPEG4V3:
  78         s->h263_msmpeg4 = 1;
  79         s->h263_pred = 1;
  80         s->msmpeg4_version=3;
  81         break;
  82     case CODEC_ID_WMV1:
  83         s->h263_msmpeg4 = 1;
  84         s->h263_pred = 1;
  85         s->msmpeg4_version=4;
  86         break;
  87     case CODEC_ID_WMV2:
  88         s->h263_msmpeg4 = 1;
  89         s->h263_pred = 1;
  90         s->msmpeg4_version=5;
  91         break;
  92     case CODEC_ID_VC1:
  93     case CODEC_ID_WMV3:
  94         s->h263_msmpeg4 = 1;
  95         s->h263_pred = 1;
  96         s->msmpeg4_version=6;
  97         break;
  98     case CODEC_ID_H263I:
  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  * returns 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     const int mb_size= 16>>s->avctx->lowres;
 153     s->last_resync_gb= s->gb;
 154     s->first_slice_line= 1;
 155
 156     s->resync_mb_x= s->mb_x;
 157     s->resync_mb_y= s->mb_y;
 158
 159     ff_set_qscale(s, 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         ff_set_qscale(s, qscale);
 174     }
 175
 176     for(; s->mb_y < s->mb_height; s->mb_y++) {
 177         /* per-row end of slice checks */
 178         if(s->msmpeg4_version){
 179             if(s->resync_mb_y + s->slice_height == s->mb_y){
 180                 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);
 181
 182                 return 0;
 183             }
 184         }
 185
 186         if(s->msmpeg4_version==1){
 187             s->last_dc[0]=
 188             s->last_dc[1]=
 189             s->last_dc[2]= 128;
 190         }
 191
 192         ff_init_block_index(s);
 193         for(; s->mb_x < s->mb_width; s->mb_x++) {
 194             int ret;
 195
 196             ff_update_block_index(s);
 197
 198             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
 199                 s->first_slice_line=0;
 200             }
 201
 202             /* DCT & quantize */
 203
 204             s->mv_dir = MV_DIR_FORWARD;
 205             s->mv_type = MV_TYPE_16X16;
 206 //            s->mb_skipped = 0;
 207 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 208             ret= s->decode_mb(s, s->block);
 209
 210             if (s->pict_type!=B_TYPE)
 211                 ff_h263_update_motion_val(s);
 212
 213             if(ret<0){
 214                 const int xy= s->mb_x + s->mb_y*s->mb_stride;
 215                 if(ret==SLICE_END){
 216                     MPV_decode_mb(s, s->block);
 217                     if(s->loop_filter)
 218                         ff_h263_loop_filter(s);
 219
 220 //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));
 221                     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);
 222
 223                     s->padding_bug_score--;
 224
 225                     if(++s->mb_x >= s->mb_width){
 226                         s->mb_x=0;
 227                         ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
 228                         s->mb_y++;
 229                     }
 230                     return 0;
 231                 }else if(ret==SLICE_NOEND){
 232                     av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
 233                     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);
 234                     return -1;
 235                 }
 236                 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
 237                 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);
 238
 239                 return -1;
 240             }
 241
 242             MPV_decode_mb(s, s->block);
 243             if(s->loop_filter)
 244                 ff_h263_loop_filter(s);
 245         }
 246
 247         ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
 248
 249         s->mb_x= 0;
 250     }
 251
 252     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 253
 254     /* try to detect the padding bug */
 255     if(      s->codec_id==CODEC_ID_MPEG4
 256        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 257        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 258        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 259 //       &&   !s->resync_marker
 260        &&   !s->data_partitioning){
 261
 262         const int bits_count= get_bits_count(&s->gb);
 263         const int bits_left = s->gb.size_in_bits - bits_count;
 264
 265         if(bits_left==0){
 266             s->padding_bug_score+=16;
 267         } else if(bits_left != 1){
 268             int v= show_bits(&s->gb, 8);
 269             v|= 0x7F >> (7-(bits_count&7));
 270
 271             if(v==0x7F && bits_left<=8)
 272                 s->padding_bug_score--;
 273             else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
 274                 s->padding_bug_score+= 4;
 275             else
 276                 s->padding_bug_score++;
 277         }
 278     }
 279
 280     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 281         if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version || !s->resync_marker)*/)
 282             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 283         else
 284             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 285     }
 286
 287     // handle formats which don't have unique end markers
 288     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 289         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
 290         int max_extra=7;
 291
 292         /* no markers in M$ crap */
 293         if(s->msmpeg4_version && s->pict_type==I_TYPE)
 294             max_extra+= 17;
 295
 296         /* buggy padding but the frame should still end approximately at the bitstream end */
 297         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
 298             max_extra+= 48;
 299         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 300             max_extra+= 256*256*256*64;
 301
 302         if(left>max_extra){
 303             av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 304         }
 305         else if(left<0){
 306             av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
 307         }else
 308             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);
 309
 310         return 0;
 311     }
 312
 313     av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
 314             s->gb.size_in_bits - get_bits_count(&s->gb),
 315             show_bits(&s->gb, 24), s->padding_bug_score);
 316
 317     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);
 318
 319     return -1;
 320 }
 321
 322 int ff_h263_decode_frame(AVCodecContext *avctx,
 323                              void *data, int *data_size,
 324                              uint8_t *buf, int buf_size)
 325 {
 326     MpegEncContext *s = avctx->priv_data;
 327     int ret;
 328     AVFrame *pict = data;
 329
 330 #ifdef PRINT_FRAME_TIME
 331 uint64_t time= rdtsc();
 332 #endif
 333 #ifdef DEBUG
 334     av_log(avctx, AV_LOG_DEBUG, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
 335     if(buf_size>0)
 336         av_log(avctx, AV_LOG_DEBUG, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 337 #endif
 338     s->flags= avctx->flags;
 339     s->flags2= avctx->flags2;
 340
 341     /* no supplementary picture */
 342     if (buf_size == 0) {
 343         /* special case for last picture */
 344         if (s->low_delay==0 && s->next_picture_ptr) {
 345             *pict= *(AVFrame*)s->next_picture_ptr;
 346             s->next_picture_ptr= NULL;
 347
 348             *data_size = sizeof(AVFrame);
 349         }
 350
 351         return 0;
 352     }
 353
 354     if(s->flags&CODEC_FLAG_TRUNCATED){
 355         int next;
 356
 357         if(s->codec_id==CODEC_ID_MPEG4){
 358             next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
 359         }else if(s->codec_id==CODEC_ID_H263){
 360             next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
 361         }else{
 362             av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
 363             return -1;
 364         }
 365
 366         if( ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
 367             return buf_size;
 368     }
 369
 370
 371 retry:
 372
 373     if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
 374         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 375     }else
 376         init_get_bits(&s->gb, buf, buf_size*8);
 377     s->bitstream_buffer_size=0;
 378
 379     if (!s->context_initialized) {
 380         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 381             return -1;
 382     }
 383
 384     //we need to set current_picture_ptr before reading the header, otherwise we cant store anyting im there
 385     if(s->current_picture_ptr==NULL || s->current_picture_ptr->data[0]){
 386         int i= ff_find_unused_picture(s, 0);
 387         s->current_picture_ptr= &s->picture[i];
 388     }
 389
 390     /* let's go :-) */
 391     if (s->msmpeg4_version==5) {
 392         ret= ff_wmv2_decode_picture_header(s);
 393     } else if (s->msmpeg4_version) {
 394         ret = msmpeg4_decode_picture_header(s);
 395     } else if (s->h263_pred) {
 396         if(s->avctx->extradata_size && s->picture_number==0){
 397             GetBitContext gb;
 398
 399             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 400             ret = ff_mpeg4_decode_picture_header(s, &gb);
 401         }
 402         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 403
 404         if(s->flags& CODEC_FLAG_LOW_DELAY)
 405             s->low_delay=1;
 406     } else if (s->codec_id == CODEC_ID_H263I) {
 407         ret = intel_h263_decode_picture_header(s);
 408     } else if (s->h263_flv) {
 409         ret = flv_h263_decode_picture_header(s);
 410     } else {
 411         ret = h263_decode_picture_header(s);
 412     }
 413
 414     if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
 415
 416     /* skip if the header was thrashed */
 417     if (ret < 0){
 418         av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
 419         return -1;
 420     }
 421
 422     avctx->has_b_frames= !s->low_delay;
 423
 424     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 425         if(s->stream_codec_tag == ff_get_fourcc("XVID") ||
 426            s->codec_tag == ff_get_fourcc("XVID") || s->codec_tag == ff_get_fourcc("XVIX") ||
 427            s->codec_tag == ff_get_fourcc("RMP4"))
 428             s->xvid_build= -1;
 429 #if 0
 430         if(s->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
 431            && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
 432             s->xvid_build= -1;
 433 #endif
 434     }
 435
 436     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 437         if(s->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
 438             s->divx_version= 400; //divx 4
 439     }
 440
 441     if(s->xvid_build && s->divx_version){
 442         s->divx_version=
 443         s->divx_build= 0;
 444     }
 445
 446     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 447         if(s->codec_tag == ff_get_fourcc("XVIX"))
 448             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 449
 450         if(s->codec_tag == ff_get_fourcc("UMP4")){
 451             s->workaround_bugs|= FF_BUG_UMP4;
 452         }
 453
 454         if(s->divx_version>=500){
 455             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 456         }
 457
 458         if(s->divx_version>502){
 459             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 460         }
 461
 462         if(s->xvid_build && s->xvid_build<=3)
 463             s->padding_bug_score= 256*256*256*64;
 464
 465         if(s->xvid_build && s->xvid_build<=1)
 466             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 467
 468         if(s->xvid_build && s->xvid_build<=12)
 469             s->workaround_bugs|= FF_BUG_EDGE;
 470
 471         if(s->xvid_build && s->xvid_build<=32)
 472             s->workaround_bugs|= FF_BUG_DC_CLIP;
 473
 474 #define SET_QPEL_FUNC(postfix1, postfix2) \
 475     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 476     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 477     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 478
 479         if(s->lavc_build && s->lavc_build<4653)
 480             s->workaround_bugs|= FF_BUG_STD_QPEL;
 481
 482         if(s->lavc_build && s->lavc_build<4655)
 483             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 484
 485         if(s->lavc_build && s->lavc_build<4670){
 486             s->workaround_bugs|= FF_BUG_EDGE;
 487         }
 488
 489         if(s->lavc_build && s->lavc_build<=4712)
 490             s->workaround_bugs|= FF_BUG_DC_CLIP;
 491
 492         if(s->divx_version)
 493             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 494 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 495         if(s->divx_version==501 && s->divx_build==20020416)
 496             s->padding_bug_score= 256*256*256*64;
 497
 498         if(s->divx_version && s->divx_version<500){
 499             s->workaround_bugs|= FF_BUG_EDGE;
 500         }
 501
 502         if(s->divx_version)
 503             s->workaround_bugs|= FF_BUG_HPEL_CHROMA;
 504 #if 0
 505         if(s->divx_version==500)
 506             s->padding_bug_score= 256*256*256*64;
 507
 508         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 509          * lets hope this at least works
 510          */
 511         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 512            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 513             s->workaround_bugs|= FF_BUG_NO_PADDING;
 514
 515         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 516             s->workaround_bugs|= FF_BUG_NO_PADDING;
 517 #endif
 518     }
 519
 520     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 521         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 522         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 523         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 524         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 525         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 526         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 527
 528         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 529         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 530         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 531         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 532         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 533         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 534     }
 535
 536     if(avctx->debug & FF_DEBUG_BUGS)
 537         av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
 538                s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
 539                s->divx_packed ? "p" : "");
 540
 541 #if 0 // dump bits per frame / qp / complexity
 542 {
 543     static FILE *f=NULL;
 544     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 545     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 546 }
 547 #endif
 548
 549 #if defined(HAVE_MMX) && defined(CONFIG_GPL)
 550     if(s->codec_id == CODEC_ID_MPEG4 && s->xvid_build && avctx->idct_algo == FF_IDCT_AUTO && (mm_flags & MM_MMX)){
 551         avctx->idct_algo= FF_IDCT_XVIDMMX;
 552         avctx->coded_width= 0; // force reinit
 553 //        dsputil_init(&s->dsp, avctx);
 554         s->picture_number=0;
 555     }
 556 #endif
 557
 558         /* After H263 & mpeg4 header decode we have the height, width,*/
 559         /* and other parameters. So then we could init the picture   */
 560         /* FIXME: By the way H263 decoder is evolving it should have */
 561         /* an H263EncContext                                         */
 562
 563     if (   s->width  != avctx->coded_width
 564         || s->height != avctx->coded_height) {
 565         /* H.263 could change picture size any time */
 566         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 567         s->parse_context.buffer=0;
 568         MPV_common_end(s);
 569         s->parse_context= pc;
 570     }
 571     if (!s->context_initialized) {
 572         avcodec_set_dimensions(avctx, s->width, s->height);
 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     // for hurry_up==5
 581     s->current_picture.pict_type= s->pict_type;
 582     s->current_picture.key_frame= s->pict_type == I_TYPE;
 583
 584     /* skip B-frames if we don't have reference frames */
 585     if(s->last_picture_ptr==NULL && (s->pict_type==B_TYPE || s->dropable)) return get_consumed_bytes(s, buf_size);
 586     /* skip b frames if we are in a hurry */
 587     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 588     if(   (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==B_TYPE)
 589        || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=I_TYPE)
 590        ||  avctx->skip_frame >= AVDISCARD_ALL)
 591         return get_consumed_bytes(s, buf_size);
 592     /* skip everything if we are in a hurry>=5 */
 593     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 594
 595     if(s->next_p_frame_damaged){
 596         if(s->pict_type==B_TYPE)
 597             return get_consumed_bytes(s, buf_size);
 598         else
 599             s->next_p_frame_damaged=0;
 600     }
 601
 602     if((s->avctx->flags2 & CODEC_FLAG2_FAST) && s->pict_type==B_TYPE){
 603         s->me.qpel_put= s->dsp.put_2tap_qpel_pixels_tab;
 604         s->me.qpel_avg= s->dsp.avg_2tap_qpel_pixels_tab;
 605     }else if((!s->no_rounding) || s->pict_type==B_TYPE){
 606         s->me.qpel_put= s->dsp.put_qpel_pixels_tab;
 607         s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
 608     }else{
 609         s->me.qpel_put= s->dsp.put_no_rnd_qpel_pixels_tab;
 610         s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
 611     }
 612
 613     if(MPV_frame_start(s, avctx) < 0)
 614         return -1;
 615
 616 #ifdef DEBUG
 617     av_log(avctx, AV_LOG_DEBUG, "qscale=%d\n", s->qscale);
 618 #endif
 619
 620     ff_er_frame_start(s);
 621
 622     //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
 623     //which isnt available before MPV_frame_start()
 624     if (s->msmpeg4_version==5){
 625         if(ff_wmv2_decode_secondary_picture_header(s) < 0)
 626             return -1;
 627     }
 628
 629     /* decode each macroblock */
 630     s->mb_x=0;
 631     s->mb_y=0;
 632
 633     decode_slice(s);
 634     while(s->mb_y<s->mb_height){
 635         if(s->msmpeg4_version){
 636             if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
 637                 break;
 638         }else{
 639             if(ff_h263_resync(s)<0)
 640                 break;
 641         }
 642
 643         if(s->msmpeg4_version<4 && s->h263_pred)
 644             ff_mpeg4_clean_buffers(s);
 645
 646         decode_slice(s);
 647     }
 648
 649     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 650         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 651             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 652         }
 653
 654     /* divx 5.01+ bistream reorder stuff */
 655     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
 656         int current_pos= get_bits_count(&s->gb)>>3;
 657         int startcode_found=0;
 658
 659         if(buf_size - current_pos > 5){
 660             int i;
 661             for(i=current_pos; i<buf_size-3; i++){
 662                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 663                     startcode_found=1;
 664                     break;
 665                 }
 666             }
 667         }
 668         if(s->gb.buffer == s->bitstream_buffer && buf_size>20){ //xvid style
 669             startcode_found=1;
 670             current_pos=0;
 671         }
 672
 673         if(startcode_found){
 674             s->bitstream_buffer= av_fast_realloc(
 675                 s->bitstream_buffer,
 676                 &s->allocated_bitstream_buffer_size,
 677                 buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
 678             memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 679             s->bitstream_buffer_size= buf_size - current_pos;
 680         }
 681     }
 682
 683     ff_er_frame_end(s);
 684
 685     MPV_frame_end(s);
 686
 687 assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
 688 assert(s->current_picture.pict_type == s->pict_type);
 689     if (s->pict_type == B_TYPE || s->low_delay) {
 690         *pict= *(AVFrame*)s->current_picture_ptr;
 691     } else if (s->last_picture_ptr != NULL) {
 692         *pict= *(AVFrame*)s->last_picture_ptr;
 693     }
 694
 695     if(s->last_picture_ptr || s->low_delay){
 696         *data_size = sizeof(AVFrame);
 697         ff_print_debug_info(s, pict);
 698     }
 699
 700     /* Return the Picture timestamp as the frame number */
 701     /* we substract 1 because it is added on utils.c    */
 702     avctx->frame_number = s->picture_number - 1;
 703
 704 #ifdef PRINT_FRAME_TIME
 705 av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
 706 #endif
 707
 708     return get_consumed_bytes(s, buf_size);
 709 }
 710
 711 AVCodec mpeg4_decoder = {
 712     "mpeg4",
 713     CODEC_TYPE_VIDEO,
 714     CODEC_ID_MPEG4,
 715     sizeof(MpegEncContext),
 716     ff_h263_decode_init,
 717     NULL,
 718     ff_h263_decode_end,
 719     ff_h263_decode_frame,
 720     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 721     .flush= ff_mpeg_flush,
 722 };
 723
 724 AVCodec h263_decoder = {
 725     "h263",
 726     CODEC_TYPE_VIDEO,
 727     CODEC_ID_H263,
 728     sizeof(MpegEncContext),
 729     ff_h263_decode_init,
 730     NULL,
 731     ff_h263_decode_end,
 732     ff_h263_decode_frame,
 733     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 734     .flush= ff_mpeg_flush,
 735 };
 736
 737 AVCodec msmpeg4v1_decoder = {
 738     "msmpeg4v1",
 739     CODEC_TYPE_VIDEO,
 740     CODEC_ID_MSMPEG4V1,
 741     sizeof(MpegEncContext),
 742     ff_h263_decode_init,
 743     NULL,
 744     ff_h263_decode_end,
 745     ff_h263_decode_frame,
 746     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 747 };
 748
 749 AVCodec msmpeg4v2_decoder = {
 750     "msmpeg4v2",
 751     CODEC_TYPE_VIDEO,
 752     CODEC_ID_MSMPEG4V2,
 753     sizeof(MpegEncContext),
 754     ff_h263_decode_init,
 755     NULL,
 756     ff_h263_decode_end,
 757     ff_h263_decode_frame,
 758     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 759 };
 760
 761 AVCodec msmpeg4v3_decoder = {
 762     "msmpeg4",
 763     CODEC_TYPE_VIDEO,
 764     CODEC_ID_MSMPEG4V3,
 765     sizeof(MpegEncContext),
 766     ff_h263_decode_init,
 767     NULL,
 768     ff_h263_decode_end,
 769     ff_h263_decode_frame,
 770     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 771 };
 772
 773 AVCodec wmv1_decoder = {
 774     "wmv1",
 775     CODEC_TYPE_VIDEO,
 776     CODEC_ID_WMV1,
 777     sizeof(MpegEncContext),
 778     ff_h263_decode_init,
 779     NULL,
 780     ff_h263_decode_end,
 781     ff_h263_decode_frame,
 782     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 783 };
 784
 785 AVCodec h263i_decoder = {
 786     "h263i",
 787     CODEC_TYPE_VIDEO,
 788     CODEC_ID_H263I,
 789     sizeof(MpegEncContext),
 790     ff_h263_decode_init,
 791     NULL,
 792     ff_h263_decode_end,
 793     ff_h263_decode_frame,
 794     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 795 };
 796
 797 AVCodec flv_decoder = {
 798     "flv",
 799     CODEC_TYPE_VIDEO,
 800     CODEC_ID_FLV1,
 801     sizeof(MpegEncContext),
 802     ff_h263_decode_init,
 803     NULL,
 804     ff_h263_decode_end,
 805     ff_h263_decode_frame,
 806     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1
 807 };