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   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
  25  * H.263 decoder.
  26  */
  27
  28 #define UNCHECKED_BITSTREAM_READER 1
  29
  30 #include "libavutil/cpu.h"
  31 #include "internal.h"
  32 #include "avcodec.h"
  33 #include "error_resilience.h"
  34 #include "mpegvideo.h"
  35 #include "h263.h"
  36 #include "h263_parser.h"
  37 #include "mpeg4video_parser.h"
  38 #include "msmpeg4.h"
  39 #include "vdpau_internal.h"
  40 #include "thread.h"
  41 #include "flv.h"
  42 #include "mpeg4video.h"
  43
  44 av_cold int ff_h263_decode_init(AVCodecContext *avctx)
  45 {
  46     MpegEncContext *s = avctx->priv_data;
  47     int ret;
  48
  49     s->avctx = avctx;
  50     s->out_format = FMT_H263;
  51
  52     s->width  = avctx->coded_width;
  53     s->height = avctx->coded_height;
  54     s->workaround_bugs= avctx->workaround_bugs;
  55
  56     // set defaults
  57     ff_MPV_decode_defaults(s);
  58     s->quant_precision=5;
  59     s->decode_mb= ff_h263_decode_mb;
  60     s->low_delay= 1;
  61     if (avctx->codec->id == AV_CODEC_ID_MSS2)
  62         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
  63     else
  64         avctx->pix_fmt = avctx->get_format(avctx, avctx->codec->pix_fmts);
  65     s->unrestricted_mv= 1;
  66
  67     /* select sub codec */
  68     switch(avctx->codec->id) {
  69     case AV_CODEC_ID_H263:
  70     case AV_CODEC_ID_H263P:
  71         s->unrestricted_mv= 0;
  72         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
  73         break;
  74     case AV_CODEC_ID_MPEG4:
  75         break;
  76     case AV_CODEC_ID_MSMPEG4V1:
  77         s->h263_pred = 1;
  78         s->msmpeg4_version=1;
  79         break;
  80     case AV_CODEC_ID_MSMPEG4V2:
  81         s->h263_pred = 1;
  82         s->msmpeg4_version=2;
  83         break;
  84     case AV_CODEC_ID_MSMPEG4V3:
  85         s->h263_pred = 1;
  86         s->msmpeg4_version=3;
  87         break;
  88     case AV_CODEC_ID_WMV1:
  89         s->h263_pred = 1;
  90         s->msmpeg4_version=4;
  91         break;
  92     case AV_CODEC_ID_WMV2:
  93         s->h263_pred = 1;
  94         s->msmpeg4_version=5;
  95         break;
  96     case AV_CODEC_ID_VC1:
  97     case AV_CODEC_ID_WMV3:
  98     case AV_CODEC_ID_VC1IMAGE:
  99     case AV_CODEC_ID_WMV3IMAGE:
 100     case AV_CODEC_ID_MSS2:
 101         s->h263_pred = 1;
 102         s->msmpeg4_version=6;
 103         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
 104         break;
 105     case AV_CODEC_ID_H263I:
 106         break;
 107     case AV_CODEC_ID_FLV1:
 108         s->h263_flv = 1;
 109         break;
 110     default:
 111         return AVERROR(EINVAL);
 112     }
 113     s->codec_id= avctx->codec->id;
 114     avctx->hwaccel= ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
 115
 116     if (avctx->stream_codec_tag == AV_RL32("l263") && avctx->extradata_size == 56 && avctx->extradata[0] == 1)
 117         s->ehc_mode = 1;
 118
 119     /* for h263, we allocate the images after having read the header */
 120     if (avctx->codec->id != AV_CODEC_ID_H263 && avctx->codec->id != AV_CODEC_ID_H263P && avctx->codec->id != AV_CODEC_ID_MPEG4)
 121         if ((ret = ff_MPV_common_init(s)) < 0)
 122             return ret;
 123
 124         ff_h263_decode_init_vlc();
 125
 126     return 0;
 127 }
 128
 129 av_cold int ff_h263_decode_end(AVCodecContext *avctx)
 130 {
 131     MpegEncContext *s = avctx->priv_data;
 132
 133     ff_MPV_common_end(s);
 134     return 0;
 135 }
 136
 137 /**
 138  * Return the number of bytes consumed for building the current frame.
 139  */
 140 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
 141     int pos= (get_bits_count(&s->gb)+7)>>3;
 142
 143     if(s->divx_packed || s->avctx->hwaccel){
 144         //we would have to scan through the whole buf to handle the weird reordering ...
 145         return buf_size;
 146     }else if(s->flags&CODEC_FLAG_TRUNCATED){
 147         pos -= s->parse_context.last_index;
 148         if(pos<0) pos=0; // padding is not really read so this might be -1
 149         return pos;
 150     }else{
 151         if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
 152         if(pos+10>buf_size) pos=buf_size; // oops ;)
 153
 154         return pos;
 155     }
 156 }
 157
 158 static int decode_slice(MpegEncContext *s){
 159     const int part_mask= s->partitioned_frame ? (ER_AC_END|ER_AC_ERROR) : 0x7F;
 160     const int mb_size= 16>>s->avctx->lowres;
 161     int ret;
 162
 163     s->last_resync_gb= s->gb;
 164     s->first_slice_line= 1;
 165
 166     s->resync_mb_x= s->mb_x;
 167     s->resync_mb_y= s->mb_y;
 168
 169     ff_set_qscale(s, s->qscale);
 170
 171     if (s->avctx->hwaccel) {
 172         const uint8_t *start= s->gb.buffer + get_bits_count(&s->gb)/8;
 173         const uint8_t *end  = ff_h263_find_resync_marker(s, start + 1, s->gb.buffer_end);
 174         skip_bits_long(&s->gb, 8*(end - start));
 175         return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start);
 176     }
 177
 178     if(s->partitioned_frame){
 179         const int qscale= s->qscale;
 180
 181         if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4){
 182             if ((ret = ff_mpeg4_decode_partitions(s)) < 0)
 183                 return ret;
 184         }
 185
 186         /* restore variables which were modified */
 187         s->first_slice_line=1;
 188         s->mb_x= s->resync_mb_x;
 189         s->mb_y= s->resync_mb_y;
 190         ff_set_qscale(s, qscale);
 191     }
 192
 193     for(; s->mb_y < s->mb_height; s->mb_y++) {
 194         /* per-row end of slice checks */
 195         if(s->msmpeg4_version){
 196             if(s->resync_mb_y + s->slice_height == s->mb_y){
 197                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
 198
 199                 return 0;
 200             }
 201         }
 202
 203         if(s->msmpeg4_version==1){
 204             s->last_dc[0]=
 205             s->last_dc[1]=
 206             s->last_dc[2]= 128;
 207         }
 208
 209         ff_init_block_index(s);
 210         for(; s->mb_x < s->mb_width; s->mb_x++) {
 211             int ret;
 212
 213             ff_update_block_index(s);
 214
 215             if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
 216                 s->first_slice_line=0;
 217             }
 218
 219             /* DCT & quantize */
 220
 221             s->mv_dir = MV_DIR_FORWARD;
 222             s->mv_type = MV_TYPE_16X16;
 223 //            s->mb_skipped = 0;
 224             av_dlog(s, "%d %d %06X\n",
 225                     ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
 226             ret= s->decode_mb(s, s->block);
 227
 228             if (s->pict_type!=AV_PICTURE_TYPE_B)
 229                 ff_h263_update_motion_val(s);
 230
 231             if(ret<0){
 232                 const int xy= s->mb_x + s->mb_y*s->mb_stride;
 233                 if(ret==SLICE_END){
 234                     ff_MPV_decode_mb(s, s->block);
 235                     if(s->loop_filter)
 236                         ff_h263_loop_filter(s);
 237
 238                     ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
 239
 240                     s->padding_bug_score--;
 241
 242                     if(++s->mb_x >= s->mb_width){
 243                         s->mb_x=0;
 244                         ff_mpeg_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
 245                         ff_MPV_report_decode_progress(s);
 246                         s->mb_y++;
 247                     }
 248                     return 0;
 249                 }else if(ret==SLICE_NOEND){
 250                     av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
 251                     ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, ER_MB_END&part_mask);
 252                     return AVERROR_INVALIDDATA;
 253                 }
 254                 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
 255                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR&part_mask);
 256
 257                 return AVERROR_INVALIDDATA;
 258             }
 259
 260             ff_MPV_decode_mb(s, s->block);
 261             if(s->loop_filter)
 262                 ff_h263_loop_filter(s);
 263         }
 264
 265         ff_mpeg_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
 266         ff_MPV_report_decode_progress(s);
 267
 268         s->mb_x= 0;
 269     }
 270
 271     av_assert1(s->mb_x==0 && s->mb_y==s->mb_height);
 272
 273     if(s->codec_id==AV_CODEC_ID_MPEG4
 274        && (s->workaround_bugs&FF_BUG_AUTODETECT)
 275        && get_bits_left(&s->gb) >= 48
 276        && show_bits(&s->gb, 24)==0x4010
 277        && !s->data_partitioning)
 278         s->padding_bug_score+=32;
 279
 280     /* try to detect the padding bug */
 281     if(      s->codec_id==AV_CODEC_ID_MPEG4
 282        &&   (s->workaround_bugs&FF_BUG_AUTODETECT)
 283        &&    get_bits_left(&s->gb) >=0
 284        &&    get_bits_left(&s->gb) < 137
 285 //       &&   !s->resync_marker
 286        &&   !s->data_partitioning){
 287
 288         const int bits_count= get_bits_count(&s->gb);
 289         const int bits_left = s->gb.size_in_bits - bits_count;
 290
 291         if(bits_left==0){
 292             s->padding_bug_score+=16;
 293         } else if(bits_left != 1){
 294             int v= show_bits(&s->gb, 8);
 295             v|= 0x7F >> (7-(bits_count&7));
 296
 297             if(v==0x7F && bits_left<=8)
 298                 s->padding_bug_score--;
 299             else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
 300                 s->padding_bug_score+= 4;
 301             else
 302                 s->padding_bug_score++;
 303         }
 304     }
 305
 306     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 307         if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version>=0 || !s->resync_marker)*/)
 308             s->workaround_bugs |=  FF_BUG_NO_PADDING;
 309         else
 310             s->workaround_bugs &= ~FF_BUG_NO_PADDING;
 311     }
 312
 313     // handle formats which don't have unique end markers
 314     if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
 315         int left= get_bits_left(&s->gb);
 316         int max_extra=7;
 317
 318         /* no markers in M$ crap */
 319         if(s->msmpeg4_version && s->pict_type==AV_PICTURE_TYPE_I)
 320             max_extra+= 17;
 321
 322         /* buggy padding but the frame should still end approximately at the bitstream end */
 323         if((s->workaround_bugs&FF_BUG_NO_PADDING) && (s->err_recognition&(AV_EF_BUFFER|AV_EF_AGGRESSIVE)))
 324             max_extra+= 48;
 325         else if((s->workaround_bugs&FF_BUG_NO_PADDING))
 326             max_extra+= 256*256*256*64;
 327
 328         if(left>max_extra){
 329             av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
 330         }
 331         else if(left<0){
 332             av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
 333         }else
 334             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
 335
 336         return 0;
 337     }
 338
 339     av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
 340             get_bits_left(&s->gb),
 341             show_bits(&s->gb, 24), s->padding_bug_score);
 342
 343     ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
 344
 345     return AVERROR_INVALIDDATA;
 346 }
 347
 348 int ff_h263_decode_frame(AVCodecContext *avctx,
 349                              void *data, int *got_frame,
 350                              AVPacket *avpkt)
 351 {
 352     const uint8_t *buf = avpkt->data;
 353     int buf_size = avpkt->size;
 354     MpegEncContext *s = avctx->priv_data;
 355     int ret;
 356     AVFrame *pict = data;
 357
 358     s->flags= avctx->flags;
 359     s->flags2= avctx->flags2;
 360
 361     /* no supplementary picture */
 362     if (buf_size == 0) {
 363         /* special case for last picture */
 364         if (s->low_delay==0 && s->next_picture_ptr) {
 365             if ((ret = av_frame_ref(pict, &s->next_picture_ptr->f)) < 0)
 366                 return ret;
 367             s->next_picture_ptr= NULL;
 368
 369             *got_frame = 1;
 370         }
 371
 372         return 0;
 373     }
 374
 375     if(s->flags&CODEC_FLAG_TRUNCATED){
 376         int next;
 377
 378         if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4){
 379             next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
 380         }else if(CONFIG_H263_DECODER && s->codec_id==AV_CODEC_ID_H263){
 381             next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
 382         }else if(CONFIG_H263P_DECODER && s->codec_id==AV_CODEC_ID_H263P){
 383             next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
 384         }else{
 385             av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
 386             return AVERROR(EINVAL);
 387         }
 388
 389         if( ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
 390             return buf_size;
 391     }
 392
 393
 394 retry:
 395     if(s->divx_packed && s->bitstream_buffer_size){
 396         int i;
 397         for(i=0; i<buf_size-3; i++){
 398             if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1){
 399                 if(buf[i+3]==0xB0){
 400                     av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n");
 401                     s->bitstream_buffer_size=0;
 402                 }
 403                 break;
 404             }
 405         }
 406     }
 407
 408     if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
 409         init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
 410     }else
 411         init_get_bits(&s->gb, buf, buf_size*8);
 412     s->bitstream_buffer_size=0;
 413
 414     if (!s->context_initialized) {
 415         if ((ret = ff_MPV_common_init(s)) < 0) //we need the idct permutaton for reading a custom matrix
 416             return ret;
 417     }
 418
 419     /* We need to set current_picture_ptr before reading the header,
 420      * otherwise we cannot store anyting in there */
 421     if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
 422         int i= ff_find_unused_picture(s, 0);
 423         if (i < 0)
 424             return i;
 425         s->current_picture_ptr= &s->picture[i];
 426     }
 427
 428     /* let's go :-) */
 429     if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5) {
 430         ret= ff_wmv2_decode_picture_header(s);
 431     } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
 432         ret = ff_msmpeg4_decode_picture_header(s);
 433     } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
 434         if(s->avctx->extradata_size && s->picture_number==0){
 435             GetBitContext gb;
 436
 437             init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
 438             ret = ff_mpeg4_decode_picture_header(s, &gb);
 439         }
 440         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
 441     } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
 442         ret = ff_intel_h263_decode_picture_header(s);
 443     } else if (CONFIG_FLV_DECODER && s->h263_flv) {
 444         ret = ff_flv_decode_picture_header(s);
 445     } else {
 446         ret = ff_h263_decode_picture_header(s);
 447     }
 448
 449     if (ret < 0 || ret==FRAME_SKIPPED) {
 450         if (   s->width  != avctx->coded_width
 451             || s->height != avctx->coded_height) {
 452                 av_log(s->avctx, AV_LOG_WARNING, "Reverting picture dimensions change due to header decoding failure\n");
 453                 s->width = avctx->coded_width;
 454                 s->height= avctx->coded_height;
 455         }
 456     }
 457     if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
 458
 459     /* skip if the header was thrashed */
 460     if (ret < 0){
 461         av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
 462         return ret;
 463     }
 464
 465     avctx->has_b_frames= !s->low_delay;
 466
 467     if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
 468         if(s->stream_codec_tag == AV_RL32("XVID") ||
 469            s->codec_tag == AV_RL32("XVID") || s->codec_tag == AV_RL32("XVIX") ||
 470            s->codec_tag == AV_RL32("RMP4") || s->codec_tag == AV_RL32("ZMP4") ||
 471            s->codec_tag == AV_RL32("SIPP")
 472            )
 473             s->xvid_build= 0;
 474 #if 0
 475         if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
 476            && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
 477             s->xvid_build= 0;
 478 #endif
 479     }
 480
 481     if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
 482         if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
 483             s->divx_version= 400; //divx 4
 484     }
 485
 486     if(s->xvid_build>=0 && s->divx_version>=0){
 487         s->divx_version=
 488         s->divx_build= -1;
 489     }
 490
 491     if(s->workaround_bugs&FF_BUG_AUTODETECT){
 492         if(s->codec_tag == AV_RL32("XVIX"))
 493             s->workaround_bugs|= FF_BUG_XVID_ILACE;
 494
 495         if(s->codec_tag == AV_RL32("UMP4")){
 496             s->workaround_bugs|= FF_BUG_UMP4;
 497         }
 498
 499         if(s->divx_version>=500 && s->divx_build<1814){
 500             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 501         }
 502
 503         if(s->divx_version>502 && s->divx_build<1814){
 504             s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
 505         }
 506
 507         if(s->xvid_build<=3U)
 508             s->padding_bug_score= 256*256*256*64;
 509
 510         if(s->xvid_build<=1U)
 511             s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
 512
 513         if(s->xvid_build<=12U)
 514             s->workaround_bugs|= FF_BUG_EDGE;
 515
 516         if(s->xvid_build<=32U)
 517             s->workaround_bugs|= FF_BUG_DC_CLIP;
 518
 519 #define SET_QPEL_FUNC(postfix1, postfix2) \
 520     s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
 521     s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
 522     s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
 523
 524         if(s->lavc_build<4653U)
 525             s->workaround_bugs|= FF_BUG_STD_QPEL;
 526
 527         if(s->lavc_build<4655U)
 528             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 529
 530         if(s->lavc_build<4670U){
 531             s->workaround_bugs|= FF_BUG_EDGE;
 532         }
 533
 534         if(s->lavc_build<=4712U)
 535             s->workaround_bugs|= FF_BUG_DC_CLIP;
 536
 537         if(s->divx_version>=0)
 538             s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
 539         if(s->divx_version==501 && s->divx_build==20020416)
 540             s->padding_bug_score= 256*256*256*64;
 541
 542         if(s->divx_version<500U){
 543             s->workaround_bugs|= FF_BUG_EDGE;
 544         }
 545
 546         if(s->divx_version>=0)
 547             s->workaround_bugs|= FF_BUG_HPEL_CHROMA;
 548 #if 0
 549         if(s->divx_version==500)
 550             s->padding_bug_score= 256*256*256*64;
 551
 552         /* very ugly XVID padding bug detection FIXME/XXX solve this differently
 553          * Let us hope this at least works.
 554          */
 555         if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==-1
 556            && s->codec_id==AV_CODEC_ID_MPEG4 && s->vo_type==0)
 557             s->workaround_bugs|= FF_BUG_NO_PADDING;
 558
 559         if(s->lavc_build<4609U) //FIXME not sure about the version num but a 4609 file seems ok
 560             s->workaround_bugs|= FF_BUG_NO_PADDING;
 561 #endif
 562     }
 563
 564     if(s->workaround_bugs& FF_BUG_STD_QPEL){
 565         SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
 566         SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
 567         SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
 568         SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
 569         SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
 570         SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
 571
 572         SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
 573         SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
 574         SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
 575         SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
 576         SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
 577         SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
 578     }
 579
 580     if(avctx->debug & FF_DEBUG_BUGS)
 581         av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
 582                s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
 583                s->divx_packed ? "p" : "");
 584
 585 #if HAVE_MMX
 586     if (s->codec_id == AV_CODEC_ID_MPEG4 && s->xvid_build>=0 && avctx->idct_algo == FF_IDCT_AUTO && (av_get_cpu_flags() & AV_CPU_FLAG_MMX)) {
 587         avctx->idct_algo= FF_IDCT_XVIDMMX;
 588         ff_dct_common_init(s);
 589         goto retry;
 590     }
 591 #endif
 592
 593         /* After H263 & mpeg4 header decode we have the height, width,*/
 594         /* and other parameters. So then we could init the picture   */
 595         /* FIXME: By the way H263 decoder is evolving it should have */
 596         /* an H263EncContext                                         */
 597
 598     if ((!avctx->coded_width || !avctx->coded_height) && 0) {
 599         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 600
 601         s->parse_context.buffer=0;
 602         ff_MPV_common_end(s);
 603         s->parse_context= pc;
 604         avcodec_set_dimensions(avctx, s->width, s->height);
 605
 606         goto retry;
 607     }
 608
 609     if (s->width  != avctx->coded_width  ||
 610         s->height != avctx->coded_height ||
 611         s->context_reinit) {
 612         /* H.263 could change picture size any time */
 613         s->context_reinit = 0;
 614
 615         avcodec_set_dimensions(avctx, s->width, s->height);
 616
 617         if ((ret = ff_MPV_common_frame_size_change(s)))
 618             return ret;
 619     }
 620
 621     if((s->codec_id==AV_CODEC_ID_H263 || s->codec_id==AV_CODEC_ID_H263P || s->codec_id == AV_CODEC_ID_H263I))
 622         s->gob_index = ff_h263_get_gob_height(s);
 623
 624     // for skipping the frame
 625     s->current_picture.f.pict_type = s->pict_type;
 626     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
 627
 628     /* skip B-frames if we don't have reference frames */
 629     if (s->last_picture_ptr == NULL &&
 630         (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))
 631         return get_consumed_bytes(s, buf_size);
 632     if(   (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==AV_PICTURE_TYPE_B)
 633        || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=AV_PICTURE_TYPE_I)
 634        ||  avctx->skip_frame >= AVDISCARD_ALL)
 635         return get_consumed_bytes(s, buf_size);
 636
 637     if(s->next_p_frame_damaged){
 638         if(s->pict_type==AV_PICTURE_TYPE_B)
 639             return get_consumed_bytes(s, buf_size);
 640         else
 641             s->next_p_frame_damaged=0;
 642     }
 643
 644     if((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
 645         s->me.qpel_put= s->dsp.put_qpel_pixels_tab;
 646         s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
 647     }else{
 648         s->me.qpel_put= s->dsp.put_no_rnd_qpel_pixels_tab;
 649         s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
 650     }
 651
 652     if ((ret = ff_MPV_frame_start(s, avctx)) < 0)
 653         return ret;
 654
 655     if (!s->divx_packed && !avctx->hwaccel)
 656         ff_thread_finish_setup(avctx);
 657
 658     if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) {
 659         ff_vdpau_mpeg4_decode_picture(s, s->gb.buffer, s->gb.buffer_end - s->gb.buffer);
 660         goto frame_end;
 661     }
 662
 663     if (avctx->hwaccel) {
 664         if ((ret = avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer)) < 0)
 665             return ret;
 666     }
 667
 668     ff_mpeg_er_frame_start(s);
 669
 670     //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
 671     //which is not available before ff_MPV_frame_start()
 672     if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5){
 673         ret = ff_wmv2_decode_secondary_picture_header(s);
 674         if(ret<0) return ret;
 675         if(ret==1) goto intrax8_decoded;
 676     }
 677
 678     /* decode each macroblock */
 679     s->mb_x=0;
 680     s->mb_y=0;
 681
 682     ret = decode_slice(s);
 683     while(s->mb_y<s->mb_height){
 684         if(s->msmpeg4_version){
 685             if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_left(&s->gb)<0)
 686                 break;
 687         }else{
 688             int prev_x=s->mb_x, prev_y=s->mb_y;
 689             if(ff_h263_resync(s)<0)
 690                 break;
 691             if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
 692                 s->er.error_occurred = 1;
 693         }
 694
 695         if(s->msmpeg4_version<4 && s->h263_pred)
 696             ff_mpeg4_clean_buffers(s);
 697
 698         if (decode_slice(s) < 0) ret = AVERROR_INVALIDDATA;
 699     }
 700
 701     if (s->msmpeg4_version && s->msmpeg4_version<4 && s->pict_type==AV_PICTURE_TYPE_I)
 702         if(!CONFIG_MSMPEG4_DECODER || ff_msmpeg4_decode_ext_header(s, buf_size) < 0){
 703             s->er.error_status_table[s->mb_num - 1] = ER_MB_ERROR;
 704         }
 705
 706     av_assert1(s->bitstream_buffer_size==0);
 707 frame_end:
 708     /* divx 5.01+ bitstream reorder stuff */
 709     if(s->codec_id==AV_CODEC_ID_MPEG4 && s->divx_packed){
 710         int current_pos= s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb)>>3);
 711         int startcode_found=0;
 712
 713         if(buf_size - current_pos > 7){
 714             int i;
 715             for(i=current_pos; i<buf_size-4; i++){
 716                 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
 717                     startcode_found=!(buf[i+4]&0x40);
 718                     break;
 719                 }
 720             }
 721         }
 722
 723         if(startcode_found){
 724             av_fast_malloc(
 725                 &s->bitstream_buffer,
 726                 &s->allocated_bitstream_buffer_size,
 727                 buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
 728             if (!s->bitstream_buffer)
 729                 return AVERROR(ENOMEM);
 730             memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
 731             s->bitstream_buffer_size= buf_size - current_pos;
 732         }
 733     }
 734
 735 intrax8_decoded:
 736     ff_er_frame_end(&s->er);
 737
 738     if (avctx->hwaccel) {
 739         if ((ret = avctx->hwaccel->end_frame(avctx)) < 0)
 740             return ret;
 741     }
 742
 743     ff_MPV_frame_end(s);
 744
 745     if (!s->divx_packed && avctx->hwaccel)
 746         ff_thread_finish_setup(avctx);
 747
 748     av_assert1(s->current_picture.f.pict_type == s->current_picture_ptr->f.pict_type);
 749     av_assert1(s->current_picture.f.pict_type == s->pict_type);
 750     if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
 751         if ((ret = av_frame_ref(pict, &s->current_picture_ptr->f)) < 0)
 752             return ret;
 753         ff_print_debug_info(s, s->current_picture_ptr, pict);
 754         ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG1);
 755     } else if (s->last_picture_ptr != NULL) {
 756         if ((ret = av_frame_ref(pict, &s->last_picture_ptr->f)) < 0)
 757             return ret;
 758         ff_print_debug_info(s, s->last_picture_ptr, pict);
 759         ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG1);
 760     }
 761
 762     if(s->last_picture_ptr || s->low_delay){
 763         if (   pict->format == AV_PIX_FMT_YUV420P
 764             && (s->codec_tag == AV_RL32("GEOV") || s->codec_tag == AV_RL32("GEOX"))) {
 765             int x, y, p;
 766             av_frame_make_writable(pict);
 767             for (p=0; p<3; p++) {
 768                 int w = FF_CEIL_RSHIFT(pict-> width, !!p);
 769                 int h = FF_CEIL_RSHIFT(pict->height, !!p);
 770                 int linesize = pict->linesize[p];
 771                 for (y=0; y<(h>>1); y++)
 772                     for (x=0; x<w; x++)
 773                         FFSWAP(int,
 774                                pict->data[p][x + y*linesize],
 775                                pict->data[p][x + (h-1-y)*linesize]);
 776             }
 777         }
 778         *got_frame = 1;
 779     }
 780
 781     return (ret && (avctx->err_recognition & AV_EF_EXPLODE))?ret:get_consumed_bytes(s, buf_size);
 782 }
 783
 784 const enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[] = {
 785 #if CONFIG_VAAPI
 786     AV_PIX_FMT_VAAPI_VLD,
 787 #endif
 788 #if CONFIG_VDPAU
 789     AV_PIX_FMT_VDPAU,
 790 #endif
 791     AV_PIX_FMT_YUV420P,
 792     AV_PIX_FMT_NONE
 793 };
 794
 795 AVCodec ff_h263_decoder = {
 796     .name           = "h263",
 797     .type           = AVMEDIA_TYPE_VIDEO,
 798     .id             = AV_CODEC_ID_H263,
 799     .priv_data_size = sizeof(MpegEncContext),
 800     .init           = ff_h263_decode_init,
 801     .close          = ff_h263_decode_end,
 802     .decode         = ff_h263_decode_frame,
 803     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
 804                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 805     .flush          = ff_mpeg_flush,
 806     .max_lowres     = 3,
 807     .long_name      = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
 808     .pix_fmts       = ff_h263_hwaccel_pixfmt_list_420,
 809 };
 810
 811 AVCodec ff_h263p_decoder = {
 812     .name           = "h263p",
 813     .type           = AVMEDIA_TYPE_VIDEO,
 814     .id             = AV_CODEC_ID_H263P,
 815     .priv_data_size = sizeof(MpegEncContext),
 816     .init           = ff_h263_decode_init,
 817     .close          = ff_h263_decode_end,
 818     .decode         = ff_h263_decode_frame,
 819     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
 820                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 821     .flush          = ff_mpeg_flush,
 822     .max_lowres     = 3,
 823     .long_name      = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
 824     .pix_fmts       = ff_h263_hwaccel_pixfmt_list_420,
 825 };