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
  32 int ff_h263_decode_init(AVCodecContext *avctx)
  33 {
  34     MpegEncContext *s = avctx->priv_data;
  35
  36     s->avctx = avctx;
  37     s->out_format = FMT_H263;
  38
  39     s->width = avctx->width;
  40     s->height = avctx->height;
  41     s->workaround_bugs= avctx->workaround_bugs;
  42
  43     // set defaults
  44     s->quant_precision=5;
  45     s->progressive_sequence=1;
  46     s->decode_mb= ff_h263_decode_mb;
  47     s->low_delay= 1;
  48     avctx->pix_fmt= PIX_FMT_YUV420P;
  49     s->unrestricted_mv= 1;
  50
  51     /* select sub codec */
  52     switch(avctx->codec->id) {
  53     case CODEC_ID_H263:
  54         s->unrestricted_mv= 0;
  55         break;
  56     case CODEC_ID_MPEG4:
  57         s->decode_mb= ff_mpeg4_decode_mb;
  58         s->time_increment_bits = 4; /* default value for broken headers */
  59         s->h263_pred = 1;
  60         s->low_delay = 0; //default, might be overriden in the vol header during header parsing
  61         break;
  62     case CODEC_ID_MSMPEG4V1:
  63         s->h263_msmpeg4 = 1;
  64         s->h263_pred = 1;
  65         s->msmpeg4_version=1;
  66         break;
  67     case CODEC_ID_MSMPEG4V2:
  68         s->h263_msmpeg4 = 1;
  69         s->h263_pred = 1;
  70         s->msmpeg4_version=2;
  71         break;
  72     case CODEC_ID_MSMPEG4V3:
  73         s->h263_msmpeg4 = 1;
  74         s->h263_pred = 1;
  75         s->msmpeg4_version=3;
  76         break;
  77     case CODEC_ID_WMV1:
  78         s->h263_msmpeg4 = 1;
  79         s->h263_pred = 1;
  80         s->msmpeg4_version=4;
  81         break;
  82     case CODEC_ID_WMV2:
  83         s->h263_msmpeg4 = 1;
  84         s->h263_pred = 1;
  85         s->msmpeg4_version=5;
  86         break;
  87     case CODEC_ID_H263I:
  88         break;
  89     case CODEC_ID_FLV1:
  90         s->h263_flv = 1;
  91         break;
  92     default:
  93         return -1;
  94     }
  95     s->codec_id= avctx->codec->id;
  96
  97     /* for h263, we allocate the images after having read the header */
  98     if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
  99         if (MPV_common_init(s) < 0)
 100             return -1;
 101
 102     if (s->h263_msmpeg4)
 103         ff_msmpeg4_decode_init(s);
 104     else
 105         h263_decode_init_vlc(s);
 106
 107     return 0;
 108 }
 109
 110 int ff_h263_decode_end(AVCodecContext *avctx)
 111 {
 112     MpegEncContext *s = avctx->priv_data;
 113
 114     MPV_common_end(s);
 115     return 0;
 116 }
 117
 118 /**
 119  * retunrs the number of bytes consumed for building the current frame
 120  */
 121 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
 122     int pos= (get_bits_count(&s->gb)+7)>>3;
 123
 124     if(s->divx_packed){
 125         //we would have to scan through the whole buf to handle the weird reordering ...
 126         return buf_size;
 127     }else if(s->flags&CODEC_FLAG_TRUNCATED){
 128         pos -= s->parse_context.last_index;
 129         if(pos<0) pos=0; // padding is not really read so this might be -1
 130         return pos;
 131     }else{
 132         if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
 133         if(pos+10>buf_size) pos=buf_size; // oops ;)
 134
 135         return pos;
 136     }
 137 }
 138
 139 static int decode_slice(MpegEncContext *s){
 140     const int part_mask= s->partitioned_frame ? (AC_END|AC_ERROR) : 0x7F;
 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     ff_set_qscale(s, s->qscale);
 148
 149     if(s->partitioned_frame){
 150         const int qscale= s->qscale;
 151
 152         if(s->codec_id==CODEC_ID_MPEG4){
 153             if(ff_mpeg4_decode_partitions(s) < 0)
 154                 return -1;
 155         }
 156
 157         /* restore variables which were modified */
 158         s->first_slice_line=1;
 159         s->mb_x= s->resync_mb_x;
 160         s->mb_y= s->resync_mb_y;
 161         ff_set_qscale(s, qscale);
 162     }
 163
 164     for(; s->mb_y < s->mb_height; s->mb_y++) {
 165         /* per-row end of slice checks */
 166         if(s->msmpeg4_version){
 167             if(s->resync_mb_y + s->slice_height == s->mb_y){
 168                 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);
 169
 170                 return 0;
 171             }
 172         }
 173
 174         if(s->msmpeg4_version==1){
 175             s->last_dc[0]=
 176             s->last_dc[1]=
 177             s->last_dc[2]= 128;
 178         }
 179
 180         ff_init_block_index(s);
 181         for(; s->mb_x < s->mb_width; s->mb_x++) {
 182             int ret;
 183
 184             ff_update_block_index(s);
 185
 186             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
 187                 s->first_slice_line=0;
 188             }
 189
 190             /* DCT & quantize */
 191             s->dsp.clear_blocks(s->block[0]);
 192
 193             s->mv_dir = MV_DIR_FORWARD;
 194             s->mv_type = MV_TYPE_16X16;
 195 //            s->mb_skiped = 0;
 196 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 197             ret= s->decode_mb(s, s->block);
 198
 199             if (s->pict_type!=B_TYPE)
 200                 ff_h263_update_motion_val(s);
 201
 202             if(ret<0){
 203                 const int xy= s->mb_x + s->mb_y*s->mb_stride;
 204                 if(ret==SLICE_END){
 205                     MPV_decode_mb(s, s->block);
 206                     if(s->loop_filter)
 207                         ff_h263_loop_filter(s);
 208
 209 //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));
 210                     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);
 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, s->mb_y*16, 16);
 217                         s->mb_y++;
 218                     }
 219                     return 0;
 220                 }else if(ret==SLICE_NOEND){
 221                     av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
 222                     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);
 223                     return -1;
 224                 }
 225                 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
 226                 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);
 227
 228                 return -1;
 229             }
 230
 231             MPV_decode_mb(s, s->block);
 232             if(s->loop_filter)
 233                 ff_h263_loop_filter(s);
 234         }
 235
 236         ff_draw_horiz_band(s, s->mb_y*16, 16);
 237
 238         s->mb_x= 0;
 239     }
 240
 241     assert(s->mb_x==0 && s->mb_y==s->mb_height);
 242
 243     /* try to detect the padding bug */
 244     if(      s->codec_id==CODEC_ID_MPEG4
 245        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 246        &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
 247        &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
 248 //       &&   !s->resync_marker
 249        &&   !s->data_partitioning){
 250
 251         const int bits_count= get_bits_count(&s->gb);
 252         const int bits_left = s->gb.size_in_bits - bits_count;
 253
 254         if(bits_left==0){
 255             s->padding_bug_score+=16;
 256         }else if(bits_left>8){
 257             s->padding_bug_score++;
 258         } else if(bits_left != 1){
 259             int v= show_bits(&s->gb, 8);
 260             v|= 0x7F >> (7-(bits_count&7));
 261
 262             if(v==0x7F)
 263                 s->padding_bug_score--;
 264             else
 265                 s->padding_bug_score++;
 266         }
 267     }
 268
 269     // handle formats which dont have unique end markers
 270     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 271         int left= s->gb.size_in_bits - get_bits_count(&s->gb);
 272         int max_extra=7;
 273
 274         /* no markers in M$ crap */
 275         if(s->msmpeg4_version && s->pict_type==I_TYPE)
 276             max_extra+= 17;
 277
 278         /* buggy padding but the frame should still end approximately at the bitstream end */
 279         if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
 280             max_extra+= 48;
 281         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 282             max_extra+= 256*256*256*64;
 283
 284         if(left>max_extra){
 285             av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 286         }
 287         else if(left<0){
 288             av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
 289         }else
 290             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);
 291
 292         return 0;
 293     }
 294
 295     av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
 296             s->gb.size_in_bits - get_bits_count(&s->gb),
 297             show_bits(&s->gb, 24), s->padding_bug_score);
 298
 299     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);
 300
 301     return -1;
 302 }
 303
 304 /**
 305  * finds the end of the current frame in the bitstream.
 306  * @return the position of the first byte of the next frame, or -1
 307  */
 308 static int mpeg4_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
 309     ParseContext *pc= &s->parse_context;
 310     int vop_found, i;
 311     uint32_t state;
 312
 313     vop_found= pc->frame_start_found;
 314     state= pc->state;
 315
 316     i=0;
 317     if(!vop_found){
 318         for(i=0; i<buf_size; i++){
 319             state= (state<<8) | buf[i];
 320             if(state == 0x1B6){
 321                 i++;
 322                 vop_found=1;
 323                 break;
 324             }
 325         }
 326     }
 327
 328     if(vop_found){
 329       for(; i<buf_size; i++){
 330         state= (state<<8) | buf[i];
 331         if((state&0xFFFFFF00) == 0x100){
 332             pc->frame_start_found=0;
 333             pc->state=-1;
 334             return i-3;
 335         }
 336       }
 337     }
 338     pc->frame_start_found= vop_found;
 339     pc->state= state;
 340     return END_NOT_FOUND;
 341 }
 342
 343 static int h263_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
 344     ParseContext *pc= &s->parse_context;
 345     int vop_found, i;
 346     uint32_t state;
 347
 348     vop_found= pc->frame_start_found;
 349     state= pc->state;
 350
 351     i=0;
 352     if(!vop_found){
 353         for(i=0; i<buf_size; i++){
 354             state= (state<<8) | buf[i];
 355             if(state>>(32-22) == 0x20){
 356                 i++;
 357                 vop_found=1;
 358                 break;
 359             }
 360         }
 361     }
 362
 363     if(vop_found){
 364       for(; i<buf_size; i++){
 365         state= (state<<8) | buf[i];
 366         if(state>>(32-22) == 0x20){
 367             pc->frame_start_found=0;
 368             pc->state=-1;
 369             return i-3;
 370         }
 371       }
 372     }
 373     pc->frame_start_found= vop_found;
 374     pc->state= state;
 375
 376     return END_NOT_FOUND;
 377 }
 378
 379 int ff_h263_decode_frame(AVCodecContext *avctx,
 380                              void *data, int *data_size,
 381                              uint8_t *buf, int buf_size)
 382 {
 383     MpegEncContext *s = avctx->priv_data;
 384     int ret;
 385     AVFrame *pict = data;
 386
 387 #ifdef PRINT_FRAME_TIME
 388 uint64_t time= rdtsc();
 389 #endif
 390 #ifdef DEBUG
 391     printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
 392     printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
 393 #endif
 394     s->flags= avctx->flags;
 395
 396     *data_size = 0;
 397
 398     /* no supplementary picture */
 399     if (buf_size == 0) {
 400         /* special case for last picture */
 401         if (s->low_delay==0 && s->next_picture_ptr) {
 402             *pict= *(AVFrame*)s->next_picture_ptr;
 403             s->next_picture_ptr= NULL;
 404
 405             *data_size = sizeof(AVFrame);
 406         }
 407
 408         return 0;
 409     }
 410
 411     if(s->flags&CODEC_FLAG_TRUNCATED){
 412         int next;
 413
 414         if(s->codec_id==CODEC_ID_MPEG4){
 415             next= mpeg4_find_frame_end(s, buf, buf_size);
 416         }else if(s->codec_id==CODEC_ID_H263){
 417             next= h263_find_frame_end(s, buf, buf_size);
 418         }else{
 419             av_log(s->avctx, AV_LOG_ERROR, "this codec doesnt support truncated bitstreams\n");
 420             return -1;
 421         }
 422
 423         if( ff_combine_frame(s, next, &buf, &buf_size) < 0 )
 424             return buf_size;
 425     }
 426
 427 retry:
 428
 429     if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
 430         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 431     }else
 432         init_get_bits(&s->gb, buf, buf_size*8);
 433     s->bitstream_buffer_size=0;
 434
 435     if (!s->context_initialized) {
 436         if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
 437             return -1;
 438     }
 439
 440     //we need to set current_picture_ptr before reading the header, otherwise we cant store anyting im there
 441     if(s->current_picture_ptr==NULL || s->current_picture_ptr->data[0]){
 442         int i= ff_find_unused_picture(s, 0);
 443         s->current_picture_ptr= &s->picture[i];
 444     }
 445
 446     /* let's go :-) */
 447     if (s->msmpeg4_version==5) {
 448         ret= ff_wmv2_decode_picture_header(s);
 449     } else if (s->msmpeg4_version) {
 450         ret = msmpeg4_decode_picture_header(s);
 451     } else if (s->h263_pred) {
 452         if(s->avctx->extradata_size && s->picture_number==0){
 453             GetBitContext gb;
 454
 455             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 456             ret = ff_mpeg4_decode_picture_header(s, &gb);
 457         }
 458         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 459
 460         if(s->flags& CODEC_FLAG_LOW_DELAY)
 461             s->low_delay=1;
 462     } else if (s->codec_id == CODEC_ID_H263I) {
 463         ret = intel_h263_decode_picture_header(s);
 464     } else if (s->h263_flv) {
 465         ret = flv_h263_decode_picture_header(s);
 466     } else {
 467         ret = h263_decode_picture_header(s);
 468     }
 469
 470     if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
 471
 472     /* skip if the header was thrashed */
 473     if (ret < 0){
 474         av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
 475         return -1;
 476     }
 477
 478     avctx->has_b_frames= !s->low_delay;
 479
 480     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 481         if(s->avctx->stream_codec_tag == ff_get_fourcc("XVID") ||
 482            s->avctx->codec_tag == ff_get_fourcc("XVID") || s->avctx->codec_tag == ff_get_fourcc("XVIX"))
 483             s->xvid_build= -1;
 484 #if 0
 485         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
 486            && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
 487             s->xvid_build= -1;
 488 #endif
 489     }
 490
 491     if(s->xvid_build==0 && s->divx_version==0 && s->lavc_build==0){
 492         if(s->avctx->codec_tag == ff_get_fourcc("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
 493             s->divx_version= 400; //divx 4
 494     }
 495
 496     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 497         s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 498
 499         if(s->padding_bug_score > -2 && !s->data_partitioning && (s->divx_version || !s->resync_marker))
 500             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 501
 502         if(s->avctx->codec_tag == ff_get_fourcc("XVIX"))
 503             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 504
 505         if(s->avctx->codec_tag == ff_get_fourcc("UMP4")){
 506             s->workaround_bugs|= FF_BUG_UMP4;
 507         }
 508
 509         if(s->divx_version>=500){
 510             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 511         }
 512
 513         if(s->divx_version>502){
 514             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 515         }
 516
 517         if(s->xvid_build && s->xvid_build<=3)
 518             s->padding_bug_score= 256*256*256*64;
 519
 520         if(s->xvid_build && s->xvid_build<=1)
 521             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 522
 523         if(s->xvid_build && s->xvid_build<=12)
 524             s->workaround_bugs|= FF_BUG_EDGE;
 525
 526 #define SET_QPEL_FUNC(postfix1, postfix2) \
 527     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 528     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 529     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 530
 531         if(s->lavc_build && s->lavc_build<4653)
 532             s->workaround_bugs|= FF_BUG_STD_QPEL;
 533
 534         if(s->lavc_build && s->lavc_build<4655)
 535             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 536
 537         if(s->lavc_build && s->lavc_build<4670){
 538             s->workaround_bugs|= FF_BUG_EDGE;
 539         }
 540
 541         if(s->divx_version)
 542             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 543 //printf("padding_bug_score: %d\n", s->padding_bug_score);
 544         if(s->divx_version==501 && s->divx_build==20020416)
 545             s->padding_bug_score= 256*256*256*64;
 546
 547         if(s->divx_version && s->divx_version<500){
 548             s->workaround_bugs|= FF_BUG_EDGE;
 549         }
 550
 551 #if 0
 552         if(s->divx_version==500)
 553             s->padding_bug_score= 256*256*256*64;
 554
 555         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 556          * lets hope this at least works
 557          */
 558         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
 559            && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
 560             s->workaround_bugs|= FF_BUG_NO_PADDING;
 561
 562         if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
 563             s->workaround_bugs|= FF_BUG_NO_PADDING;
 564 #endif
 565     }
 566
 567     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 568         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 569         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 570         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 571         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 572         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 573         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 574
 575         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 576         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 577         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 578         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 579         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 580         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 581     }
 582
 583     if(avctx->debug & FF_DEBUG_BUGS)
 584         av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
 585                s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
 586                s->divx_packed ? "p" : "");
 587
 588 #if 0 // dump bits per frame / qp / complexity
 589 {
 590     static FILE *f=NULL;
 591     if(!f) f=fopen("rate_qp_cplx.txt", "w");
 592     fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
 593 }
 594 #endif
 595
 596         /* After H263 & mpeg4 header decode we have the height, width,*/
 597         /* and other parameters. So then we could init the picture   */
 598         /* FIXME: By the way H263 decoder is evolving it should have */
 599         /* an H263EncContext                                         */
 600
 601     if (   s->width != avctx->width || s->height != avctx->height) {
 602         /* H.263 could change picture size any time */
 603         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 604         s->parse_context.buffer=0;
 605         MPV_common_end(s);
 606         s->parse_context= pc;
 607     }
 608     if (!s->context_initialized) {
 609         avctx->width = s->width;
 610         avctx->height = s->height;
 611
 612         goto retry;
 613     }
 614
 615     if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
 616         s->gob_index = ff_h263_get_gob_height(s);
 617
 618     // for hurry_up==5
 619     s->current_picture.pict_type= s->pict_type;
 620     s->current_picture.key_frame= s->pict_type == I_TYPE;
 621
 622     /* skip b frames if we dont have reference frames */
 623     if(s->last_picture_ptr==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 624     /* skip b frames if we are in a hurry */
 625     if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
 626     /* skip everything if we are in a hurry>=5 */
 627     if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
 628
 629     if(s->next_p_frame_damaged){
 630         if(s->pict_type==B_TYPE)
 631             return get_consumed_bytes(s, buf_size);
 632         else
 633             s->next_p_frame_damaged=0;
 634     }
 635
 636     if(MPV_frame_start(s, avctx) < 0)
 637         return -1;
 638
 639 #ifdef DEBUG
 640     printf("qscale=%d\n", s->qscale);
 641 #endif
 642
 643     ff_er_frame_start(s);
 644
 645     //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
 646     //which isnt available before MPV_frame_start()
 647     if (s->msmpeg4_version==5){
 648         if(ff_wmv2_decode_secondary_picture_header(s) < 0)
 649             return -1;
 650     }
 651
 652     /* decode each macroblock */
 653     s->mb_x=0;
 654     s->mb_y=0;
 655
 656     decode_slice(s);
 657     while(s->mb_y<s->mb_height){
 658         if(s->msmpeg4_version){
 659             if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
 660                 break;
 661         }else{
 662             if(ff_h263_resync(s)<0)
 663                 break;
 664         }
 665
 666         if(s->msmpeg4_version<4 && s->h263_pred)
 667             ff_mpeg4_clean_buffers(s);
 668
 669         decode_slice(s);
 670     }
 671
 672     if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
 673         if(msmpeg4_decode_ext_header(s, buf_size) < 0){
 674             s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
 675         }
 676
 677     /* divx 5.01+ bistream reorder stuff */
 678     if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
 679         int current_pos= get_bits_count(&s->gb)>>3;
 680
 681         if(   buf_size - current_pos > 5
 682            && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
 683             int i;
 684             int startcode_found=0;
 685             for(i=current_pos; i<buf_size-3; i++){
 686                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 687                     startcode_found=1;
 688                     break;
 689                 }
 690             }
 691             if(startcode_found){
 692                 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 693                 s->bitstream_buffer_size= buf_size - current_pos;
 694             }
 695         }
 696     }
 697
 698     ff_er_frame_end(s);
 699
 700     MPV_frame_end(s);
 701
 702 assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
 703 assert(s->current_picture.pict_type == s->pict_type);
 704     if(s->pict_type==B_TYPE || s->low_delay){
 705         *pict= *(AVFrame*)&s->current_picture;
 706         ff_print_debug_info(s, pict);
 707     } else {
 708         *pict= *(AVFrame*)&s->last_picture;
 709         ff_print_debug_info(s, pict);
 710     }
 711
 712     /* Return the Picture timestamp as the frame number */
 713     /* we substract 1 because it is added on utils.c    */
 714     avctx->frame_number = s->picture_number - 1;
 715
 716     /* dont output the last pic after seeking */
 717     if(s->last_picture_ptr || s->low_delay)
 718         *data_size = sizeof(AVFrame);
 719 #ifdef PRINT_FRAME_TIME
 720 printf("%Ld\n", rdtsc()-time);
 721 #endif
 722
 723     return get_consumed_bytes(s, buf_size);
 724 }
 725
 726 static const AVOption mpeg4_decoptions[] =
 727 {
 728     AVOPTION_SUB(avoptions_workaround_bug),
 729     AVOPTION_END()
 730 };
 731
 732 AVCodec mpeg4_decoder = {
 733     "mpeg4",
 734     CODEC_TYPE_VIDEO,
 735     CODEC_ID_MPEG4,
 736     sizeof(MpegEncContext),
 737     ff_h263_decode_init,
 738     NULL,
 739     ff_h263_decode_end,
 740     ff_h263_decode_frame,
 741     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 742     .options = mpeg4_decoptions,
 743     .flush= ff_mpeg_flush,
 744 };
 745
 746 AVCodec h263_decoder = {
 747     "h263",
 748     CODEC_TYPE_VIDEO,
 749     CODEC_ID_H263,
 750     sizeof(MpegEncContext),
 751     ff_h263_decode_init,
 752     NULL,
 753     ff_h263_decode_end,
 754     ff_h263_decode_frame,
 755     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
 756     .flush= ff_mpeg_flush,
 757 };
 758
 759 AVCodec msmpeg4v1_decoder = {
 760     "msmpeg4v1",
 761     CODEC_TYPE_VIDEO,
 762     CODEC_ID_MSMPEG4V1,
 763     sizeof(MpegEncContext),
 764     ff_h263_decode_init,
 765     NULL,
 766     ff_h263_decode_end,
 767     ff_h263_decode_frame,
 768     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 769     mpeg4_decoptions,
 770 };
 771
 772 AVCodec msmpeg4v2_decoder = {
 773     "msmpeg4v2",
 774     CODEC_TYPE_VIDEO,
 775     CODEC_ID_MSMPEG4V2,
 776     sizeof(MpegEncContext),
 777     ff_h263_decode_init,
 778     NULL,
 779     ff_h263_decode_end,
 780     ff_h263_decode_frame,
 781     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 782     mpeg4_decoptions,
 783 };
 784
 785 AVCodec msmpeg4v3_decoder = {
 786     "msmpeg4",
 787     CODEC_TYPE_VIDEO,
 788     CODEC_ID_MSMPEG4V3,
 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     .options = mpeg4_decoptions,
 796 };
 797
 798 AVCodec wmv1_decoder = {
 799     "wmv1",
 800     CODEC_TYPE_VIDEO,
 801     CODEC_ID_WMV1,
 802     sizeof(MpegEncContext),
 803     ff_h263_decode_init,
 804     NULL,
 805     ff_h263_decode_end,
 806     ff_h263_decode_frame,
 807     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 808     mpeg4_decoptions,
 809 };
 810
 811 AVCodec h263i_decoder = {
 812     "h263i",
 813     CODEC_TYPE_VIDEO,
 814     CODEC_ID_H263I,
 815     sizeof(MpegEncContext),
 816     ff_h263_decode_init,
 817     NULL,
 818     ff_h263_decode_end,
 819     ff_h263_decode_frame,
 820     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 821     mpeg4_decoptions,
 822 };
 823
 824 AVCodec flv_decoder = {
 825     "flv",
 826     CODEC_TYPE_VIDEO,
 827     CODEC_ID_FLV1,
 828     sizeof(MpegEncContext),
 829     ff_h263_decode_init,
 830     NULL,
 831     ff_h263_decode_end,
 832     ff_h263_decode_frame,
 833     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1
 834 };