vc1.c

    if(v->hrd_param_flag){
        for(i = 0; i < v->hrd_num_leaky_buckets; i++) {
            skip_bits(gb, 8); //hrd_full[n]
        }
    }

    if(get_bits1(gb)){
        avctx->coded_width = (get_bits(gb, 12)+1)<<1;
        avctx->coded_height = (get_bits(gb, 12)+1)<<1;
    }
    if(v->extended_mv)
        v->extended_dmv = get_bits1(gb);
    if(get_bits1(gb)) {
        av_log(avctx, AV_LOG_ERROR, "Luma scaling is not supported, expect wrong picture\n");
        skip_bits(gb, 3); // Y range, ignored for now
    }
    if(get_bits1(gb)) {
        av_log(avctx, AV_LOG_ERROR, "Chroma scaling is not supported, expect wrong picture\n");
        skip_bits(gb, 3); // UV range, ignored for now
    }

    av_log(avctx, AV_LOG_DEBUG, "Entry point info:\n"
        "BrokenLink=%i, ClosedEntry=%i, PanscanFlag=%i\n"
        "RefDist=%i, Postproc=%i, FastUVMC=%i, ExtMV=%i\n"
        "DQuant=%i, VSTransform=%i, Overlap=%i, Qmode=%i\n",
        blink, clentry, v->panscanflag, refdist, v->s.loop_filter,
        v->fastuvmc, v->extended_mv, v->dquant, v->vstransform, v->overlap, v->quantizer_mode);

    return 0;
}

static int vc1_parse_frame_header(VC1Context *v, GetBitContext* gb)
{
    int pqindex, lowquant, status;

    if(v->finterpflag) v->interpfrm = get_bits1(gb);
    skip_bits(gb, 2); //framecnt unused
    v->rangeredfrm = 0;
    if (v->rangered) v->rangeredfrm = get_bits1(gb);
    v->s.pict_type = get_bits1(gb);
    if (v->s.avctx->max_b_frames) {
        if (!v->s.pict_type) {
            if (get_bits1(gb)) v->s.pict_type = I_TYPE;
            else v->s.pict_type = B_TYPE;
        } else v->s.pict_type = P_TYPE;
    } else v->s.pict_type = v->s.pict_type ? P_TYPE : I_TYPE;

    v->bi_type = 0;
    if(v->s.pict_type == B_TYPE) {
        v->bfraction = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);
        v->bfraction = ff_vc1_bfraction_lut[v->bfraction];
        if(v->bfraction == 0) {
            v->s.pict_type = BI_TYPE;
        }
    }
    if(v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE)
        skip_bits(gb, 7); // skip buffer fullness

    /* calculate RND */
    if(v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE)
        v->rnd = 1;
    if(v->s.pict_type == P_TYPE)
        v->rnd ^= 1;

    /* Quantizer stuff */
    pqindex = get_bits(gb, 5);
    if(!pqindex) return -1;
    if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
        v->pq = ff_vc1_pquant_table[0][pqindex];
    else
        v->pq = ff_vc1_pquant_table[1][pqindex];

    v->pquantizer = 1;
    if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
        v->pquantizer = pqindex < 9;
    if (v->quantizer_mode == QUANT_NON_UNIFORM)
        v->pquantizer = 0;
    v->pqindex = pqindex;
    if (pqindex < 9) v->halfpq = get_bits1(gb);
    else v->halfpq = 0;
    if (v->quantizer_mode == QUANT_FRAME_EXPLICIT)
        v->pquantizer = get_bits1(gb);
    v->dquantfrm = 0;
    if (v->extended_mv == 1) v->mvrange = get_unary(gb, 0, 3);
    v->k_x = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
    v->k_y = v->mvrange + 8; //k_y can be 8 9 10 11
    v->range_x = 1 << (v->k_x - 1);
    v->range_y = 1 << (v->k_y - 1);
    if (v->profile == PROFILE_ADVANCED)
    {
        if (v->postprocflag) v->postproc = get_bits1(gb);
    }
    else
        if (v->multires && v->s.pict_type != B_TYPE) v->respic = get_bits(gb, 2);

    if(v->res_x8 && (v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE)){
        v->x8_type = get_bits1(gb);
    }else v->x8_type = 0;
//av_log(v->s.avctx, AV_LOG_INFO, "%c Frame: QP=[%i]%i (+%i/2) %i\n",
//        (v->s.pict_type == P_TYPE) ? 'P' : ((v->s.pict_type == I_TYPE) ? 'I' : 'B'), pqindex, v->pq, v->halfpq, v->rangeredfrm);

    if(v->s.pict_type == I_TYPE || v->s.pict_type == P_TYPE) v->use_ic = 0;

    switch(v->s.pict_type) {
    case P_TYPE:
        if (v->pq < 5) v->tt_index = 0;
        else if(v->pq < 13) v->tt_index = 1;
        else v->tt_index = 2;

        lowquant = (v->pq > 12) ? 0 : 1;
        v->mv_mode = ff_vc1_mv_pmode_table[lowquant][get_unary(gb, 1, 4)];
        if (v->mv_mode == MV_PMODE_INTENSITY_COMP)
        {
            int scale, shift, i;
            v->mv_mode2 = ff_vc1_mv_pmode_table2[lowquant][get_unary(gb, 1, 3)];
            v->lumscale = get_bits(gb, 6);
            v->lumshift = get_bits(gb, 6);
            v->use_ic = 1;
            /* fill lookup tables for intensity compensation */
            if(!v->lumscale) {
                scale = -64;
                shift = (255 - v->lumshift * 2) << 6;
                if(v->lumshift > 31)
                    shift += 128 << 6;
            } else {
                scale = v->lumscale + 32;
                if(v->lumshift > 31)
                    shift = (v->lumshift - 64) << 6;
                else
                    shift = v->lumshift << 6;
            }
            for(i = 0; i < 256; i++) {
                v->luty[i] = av_clip_uint8((scale * i + shift + 32) >> 6);
                v->lutuv[i] = av_clip_uint8((scale * (i - 128) + 128*64 + 32) >> 6);
            }
        }
        if(v->mv_mode == MV_PMODE_1MV_HPEL || v->mv_mode == MV_PMODE_1MV_HPEL_BILIN)
            v->s.quarter_sample = 0;
        else if(v->mv_mode == MV_PMODE_INTENSITY_COMP) {
            if(v->mv_mode2 == MV_PMODE_1MV_HPEL || v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN)
                v->s.quarter_sample = 0;
            else
                v->s.quarter_sample = 1;
        } else
            v->s.quarter_sample = 1;
        v->s.mspel = !(v->mv_mode == MV_PMODE_1MV_HPEL_BILIN || (v->mv_mode == MV_PMODE_INTENSITY_COMP && v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN));

        if ((v->mv_mode == MV_PMODE_INTENSITY_COMP &&
                 v->mv_mode2 == MV_PMODE_MIXED_MV)
                || v->mv_mode == MV_PMODE_MIXED_MV)
        {
            status = bitplane_decoding(v->mv_type_mb_plane, &v->mv_type_is_raw, v);
            if (status < 0) return -1;
            av_log(v->s.avctx, AV_LOG_DEBUG, "MB MV Type plane encoding: "
                   "Imode: %i, Invert: %i\n", status>>1, status&1);
        } else {
            v->mv_type_is_raw = 0;
            memset(v->mv_type_mb_plane, 0, v->s.mb_stride * v->s.mb_height);
        }
        status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);

        /* Hopefully this is correct for P frames */
        v->s.mv_table_index = get_bits(gb, 2); //but using ff_vc1_ tables
        v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

        if (v->dquant)
        {
            av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
            vop_dquant_decoding(v);
        }

        v->ttfrm = 0; //FIXME Is that so ?
        if (v->vstransform)
        {
            v->ttmbf = get_bits1(gb);
            if (v->ttmbf)
            {
                v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];
            }
        } else {
            v->ttmbf = 1;
            v->ttfrm = TT_8X8;
        }
        break;
    case B_TYPE:
        if (v->pq < 5) v->tt_index = 0;
        else if(v->pq < 13) v->tt_index = 1;
        else v->tt_index = 2;

        lowquant = (v->pq > 12) ? 0 : 1;
        v->mv_mode = get_bits1(gb) ? MV_PMODE_1MV : MV_PMODE_1MV_HPEL_BILIN;
        v->s.quarter_sample = (v->mv_mode == MV_PMODE_1MV);
        v->s.mspel = v->s.quarter_sample;

        status = bitplane_decoding(v->direct_mb_plane, &v->dmb_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Direct Type plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);
        status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);

        v->s.mv_table_index = get_bits(gb, 2);
        v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

        if (v->dquant)
        {
            av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
            vop_dquant_decoding(v);
        }

        v->ttfrm = 0;
        if (v->vstransform)
        {
            v->ttmbf = get_bits1(gb);
            if (v->ttmbf)
            {
                v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];
            }
        } else {
            v->ttmbf = 1;
            v->ttfrm = TT_8X8;
        }
        break;
    }

    if(!v->x8_type)
    {
        /* AC Syntax */
        v->c_ac_table_index = decode012(gb);
        if (v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE)
        {
            v->y_ac_table_index = decode012(gb);
        }
        /* DC Syntax */
        v->s.dc_table_index = get_bits1(gb);
    }

    if(v->s.pict_type == BI_TYPE) {
        v->s.pict_type = B_TYPE;
        v->bi_type = 1;
    }
    return 0;
}

static int vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb)
{
    int pqindex, lowquant;
    int status;

    v->p_frame_skipped = 0;

    if(v->interlace){
        v->fcm = decode012(gb);
        if(v->fcm) return -1; // interlaced frames/fields are not implemented
    }
    switch(get_unary(gb, 0, 4)) {
    case 0:
        v->s.pict_type = P_TYPE;
        break;
    case 1:
        v->s.pict_type = B_TYPE;
        break;
    case 2:
        v->s.pict_type = I_TYPE;
        break;
    case 3:
        v->s.pict_type = BI_TYPE;
        break;
    case 4:
        v->s.pict_type = P_TYPE; // skipped pic
        v->p_frame_skipped = 1;
        return 0;
    }
    if(v->tfcntrflag)
        skip_bits(gb, 8);
    if(v->broadcast) {
        if(!v->interlace || v->psf) {
            v->rptfrm = get_bits(gb, 2);
        } else {
            v->tff = get_bits1(gb);
            v->rptfrm = get_bits1(gb);
        }
    }
    if(v->panscanflag) {
        //...
    }
    v->rnd = get_bits1(gb);
    if(v->interlace)
        v->uvsamp = get_bits1(gb);
    if(v->finterpflag) v->interpfrm = get_bits1(gb);
    if(v->s.pict_type == B_TYPE) {
        v->bfraction = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);
        v->bfraction = ff_vc1_bfraction_lut[v->bfraction];
        if(v->bfraction == 0) {
            v->s.pict_type = BI_TYPE; /* XXX: should not happen here */
        }
    }
    pqindex = get_bits(gb, 5);
    if(!pqindex) return -1;
    v->pqindex = pqindex;
    if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
        v->pq = ff_vc1_pquant_table[0][pqindex];
    else
        v->pq = ff_vc1_pquant_table[1][pqindex];

    v->pquantizer = 1;
    if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
        v->pquantizer = pqindex < 9;
    if (v->quantizer_mode == QUANT_NON_UNIFORM)
        v->pquantizer = 0;
    v->pqindex = pqindex;
    if (pqindex < 9) v->halfpq = get_bits1(gb);
    else v->halfpq = 0;
    if (v->quantizer_mode == QUANT_FRAME_EXPLICIT)
        v->pquantizer = get_bits1(gb);

    if(v->s.pict_type == I_TYPE || v->s.pict_type == P_TYPE) v->use_ic = 0;

    switch(v->s.pict_type) {
    case I_TYPE:
    case BI_TYPE:
        status = bitplane_decoding(v->acpred_plane, &v->acpred_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "ACPRED plane encoding: "
                "Imode: %i, Invert: %i\n", status>>1, status&1);
        v->condover = CONDOVER_NONE;
        if(v->overlap && v->pq <= 8) {
            v->condover = decode012(gb);
            if(v->condover == CONDOVER_SELECT) {
                status = bitplane_decoding(v->over_flags_plane, &v->overflg_is_raw, v);
                if (status < 0) return -1;
                av_log(v->s.avctx, AV_LOG_DEBUG, "CONDOVER plane encoding: "
                        "Imode: %i, Invert: %i\n", status>>1, status&1);
            }
        }
        break;
    case P_TYPE:
        if(v->postprocflag)
            v->postproc = get_bits1(gb);
        if (v->extended_mv) v->mvrange = get_unary(gb, 0, 3);
        else v->mvrange = 0;
        v->k_x = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
        v->k_y = v->mvrange + 8; //k_y can be 8 9 10 11
        v->range_x = 1 << (v->k_x - 1);
        v->range_y = 1 << (v->k_y - 1);

        if (v->pq < 5) v->tt_index = 0;
        else if(v->pq < 13) v->tt_index = 1;
        else v->tt_index = 2;

        lowquant = (v->pq > 12) ? 0 : 1;
        v->mv_mode = ff_vc1_mv_pmode_table[lowquant][get_unary(gb, 1, 4)];
        if (v->mv_mode == MV_PMODE_INTENSITY_COMP)
        {
            int scale, shift, i;
            v->mv_mode2 = ff_vc1_mv_pmode_table2[lowquant][get_unary(gb, 1, 3)];
            v->lumscale = get_bits(gb, 6);
            v->lumshift = get_bits(gb, 6);
            /* fill lookup tables for intensity compensation */
            if(!v->lumscale) {
                scale = -64;
                shift = (255 - v->lumshift * 2) << 6;
                if(v->lumshift > 31)
                    shift += 128 << 6;
            } else {
                scale = v->lumscale + 32;
                if(v->lumshift > 31)
                    shift = (v->lumshift - 64) << 6;
                else
                    shift = v->lumshift << 6;
            }
            for(i = 0; i < 256; i++) {
                v->luty[i] = av_clip_uint8((scale * i + shift + 32) >> 6);
                v->lutuv[i] = av_clip_uint8((scale * (i - 128) + 128*64 + 32) >> 6);
            }
            v->use_ic = 1;
        }
        if(v->mv_mode == MV_PMODE_1MV_HPEL || v->mv_mode == MV_PMODE_1MV_HPEL_BILIN)
            v->s.quarter_sample = 0;
        else if(v->mv_mode == MV_PMODE_INTENSITY_COMP) {
            if(v->mv_mode2 == MV_PMODE_1MV_HPEL || v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN)
                v->s.quarter_sample = 0;
            else
                v->s.quarter_sample = 1;
        } else
            v->s.quarter_sample = 1;
        v->s.mspel = !(v->mv_mode == MV_PMODE_1MV_HPEL_BILIN || (v->mv_mode == MV_PMODE_INTENSITY_COMP && v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN));

        if ((v->mv_mode == MV_PMODE_INTENSITY_COMP &&
                 v->mv_mode2 == MV_PMODE_MIXED_MV)
                || v->mv_mode == MV_PMODE_MIXED_MV)
        {
            status = bitplane_decoding(v->mv_type_mb_plane, &v->mv_type_is_raw, v);
            if (status < 0) return -1;
            av_log(v->s.avctx, AV_LOG_DEBUG, "MB MV Type plane encoding: "
                   "Imode: %i, Invert: %i\n", status>>1, status&1);
        } else {
            v->mv_type_is_raw = 0;
            memset(v->mv_type_mb_plane, 0, v->s.mb_stride * v->s.mb_height);
        }
        status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);

        /* Hopefully this is correct for P frames */
        v->s.mv_table_index = get_bits(gb, 2); //but using ff_vc1_ tables
        v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];
        if (v->dquant)
        {
            av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
            vop_dquant_decoding(v);
        }

        v->ttfrm = 0; //FIXME Is that so ?
        if (v->vstransform)
        {
            v->ttmbf = get_bits1(gb);
            if (v->ttmbf)
            {
                v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];
            }
        } else {
            v->ttmbf = 1;
            v->ttfrm = TT_8X8;
        }
        break;
    case B_TYPE:
        if(v->postprocflag)
            v->postproc = get_bits1(gb);
        if (v->extended_mv) v->mvrange = get_unary(gb, 0, 3);
        else v->mvrange = 0;
        v->k_x = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
        v->k_y = v->mvrange + 8; //k_y can be 8 9 10 11
        v->range_x = 1 << (v->k_x - 1);
        v->range_y = 1 << (v->k_y - 1);

        if (v->pq < 5) v->tt_index = 0;
        else if(v->pq < 13) v->tt_index = 1;
        else v->tt_index = 2;

        lowquant = (v->pq > 12) ? 0 : 1;
        v->mv_mode = get_bits1(gb) ? MV_PMODE_1MV : MV_PMODE_1MV_HPEL_BILIN;
        v->s.quarter_sample = (v->mv_mode == MV_PMODE_1MV);
        v->s.mspel = v->s.quarter_sample;

        status = bitplane_decoding(v->direct_mb_plane, &v->dmb_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Direct Type plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);
        status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
        if (status < 0) return -1;
        av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
               "Imode: %i, Invert: %i\n", status>>1, status&1);

        v->s.mv_table_index = get_bits(gb, 2);
        v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

        if (v->dquant)
        {
            av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
            vop_dquant_decoding(v);
        }

        v->ttfrm = 0;
        if (v->vstransform)
        {
            v->ttmbf = get_bits1(gb);
            if (v->ttmbf)
            {
                v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];
            }
        } else {
            v->ttmbf = 1;
            v->ttfrm = TT_8X8;
        }
        break;
    }

    /* AC Syntax */
    v->c_ac_table_index = decode012(gb);
    if (v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE)
    {
        v->y_ac_table_index = decode012(gb);
    }
    /* DC Syntax */
    v->s.dc_table_index = get_bits1(gb);
    if ((v->s.pict_type == I_TYPE || v->s.pict_type == BI_TYPE) && v->dquant) {
        av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
        vop_dquant_decoding(v);
    }

    v->bi_type = 0;
    if(v->s.pict_type == BI_TYPE) {
        v->s.pict_type = B_TYPE;
        v->bi_type = 1;
    }
    return 0;
}

/***********************************************************************/
/**
 * @defgroup block VC-1 Block-level functions
 * @see 7.1.4, p91 and 8.1.1.7, p(1)04
 * @{
 */

/**
 * @def GET_MQUANT
 * @brief Get macroblock-level quantizer scale
 */
#define GET_MQUANT()                                           \
  if (v->dquantfrm)                                            \
  {                                                            \
    int edges = 0;                                             \
    if (v->dqprofile == DQPROFILE_ALL_MBS)                     \
    {                                                          \
      if (v->dqbilevel)                                        \
      {                                                        \
        mquant = (get_bits1(gb)) ? v->altpq : v->pq;           \
      }                                                        \
      else                                                     \
      {                                                        \
        mqdiff = get_bits(gb, 3);                              \
        if (mqdiff != 7) mquant = v->pq + mqdiff;              \
        else mquant = get_bits(gb, 5);                         \
      }                                                        \
    }                                                          \
    if(v->dqprofile == DQPROFILE_SINGLE_EDGE)                  \
        edges = 1 << v->dqsbedge;                              \
    else if(v->dqprofile == DQPROFILE_DOUBLE_EDGES)            \
        edges = (3 << v->dqsbedge) % 15;                       \
    else if(v->dqprofile == DQPROFILE_FOUR_EDGES)              \
        edges = 15;                                            \
    if((edges&1) && !s->mb_x)                                  \
        mquant = v->altpq;                                     \
    if((edges&2) && s->first_slice_line)                       \
        mquant = v->altpq;                                     \
    if((edges&4) && s->mb_x == (s->mb_width - 1))              \
        mquant = v->altpq;                                     \
    if((edges&8) && s->mb_y == (s->mb_height - 1))             \
        mquant = v->altpq;                                     \
  }

/**
 * @def GET_MVDATA(_dmv_x, _dmv_y)
 * @brief Get MV differentials
 * @see MVDATA decoding from 8.3.5.2, p(1)20
 * @param _dmv_x Horizontal differential for decoded MV
 * @param _dmv_y Vertical differential for decoded MV
 */
#define GET_MVDATA(_dmv_x, _dmv_y)                                  \
  index = 1 + get_vlc2(gb, ff_vc1_mv_diff_vlc[s->mv_table_index].table,\
                       VC1_MV_DIFF_VLC_BITS, 2);                    \
  if (index > 36)                                                   \
  {                                                                 \
    mb_has_coeffs = 1;                                              \
    index -= 37;                                                    \
  }                                                                 \
  else mb_has_coeffs = 0;                                           \
  s->mb_intra = 0;                                                  \
  if (!index) { _dmv_x = _dmv_y = 0; }                              \
  else if (index == 35)                                             \
  {                                                                 \
    _dmv_x = get_bits(gb, v->k_x - 1 + s->quarter_sample);          \
    _dmv_y = get_bits(gb, v->k_y - 1 + s->quarter_sample);          \
  }                                                                 \
  else if (index == 36)                                             \
  {                                                                 \
    _dmv_x = 0;                                                     \
    _dmv_y = 0;                                                     \
    s->mb_intra = 1;                                                \
  }                                                                 \
  else                                                              \
  {                                                                 \
    index1 = index%6;                                               \
    if (!s->quarter_sample && index1 == 5) val = 1;                 \
    else                                   val = 0;                 \
    if(size_table[index1] - val > 0)                                \
        val = get_bits(gb, size_table[index1] - val);               \
    else                                   val = 0;                 \
    sign = 0 - (val&1);                                             \
    _dmv_x = (sign ^ ((val>>1) + offset_table[index1])) - sign;     \
                                                                    \
    index1 = index/6;                                               \
    if (!s->quarter_sample && index1 == 5) val = 1;                 \
    else                                   val = 0;                 \
    if(size_table[index1] - val > 0)                                \
        val = get_bits(gb, size_table[index1] - val);               \
    else                                   val = 0;                 \
    sign = 0 - (val&1);                                             \
    _dmv_y = (sign ^ ((val>>1) + offset_table[index1])) - sign;     \
  }

/** Predict and set motion vector
 */
static inline void vc1_pred_mv(MpegEncContext *s, int n, int dmv_x, int dmv_y, int mv1, int r_x, int r_y, uint8_t* is_intra)
{
    int xy, wrap, off = 0;
    int16_t *A, *B, *C;
    int px, py;
    int sum;

    /* scale MV difference to be quad-pel */
    dmv_x <<= 1 - s->quarter_sample;
    dmv_y <<= 1 - s->quarter_sample;

    wrap = s->b8_stride;
    xy = s->block_index[n];

    if(s->mb_intra){
        s->mv[0][n][0] = s->current_picture.motion_val[0][xy][0] = 0;
        s->mv[0][n][1] = s->current_picture.motion_val[0][xy][1] = 0;
        s->current_picture.motion_val[1][xy][0] = 0;
        s->current_picture.motion_val[1][xy][1] = 0;
        if(mv1) { /* duplicate motion data for 1-MV block */
            s->current_picture.motion_val[0][xy + 1][0] = 0;
            s->current_picture.motion_val[0][xy + 1][1] = 0;
            s->current_picture.motion_val[0][xy + wrap][0] = 0;
            s->current_picture.motion_val[0][xy + wrap][1] = 0;
            s->current_picture.motion_val[0][xy + wrap + 1][0] = 0;
            s->current_picture.motion_val[0][xy + wrap + 1][1] = 0;
            s->current_picture.motion_val[1][xy + 1][0] = 0;
            s->current_picture.motion_val[1][xy + 1][1] = 0;
            s->current_picture.motion_val[1][xy + wrap][0] = 0;
            s->current_picture.motion_val[1][xy + wrap][1] = 0;
            s->current_picture.motion_val[1][xy + wrap + 1][0] = 0;
            s->current_picture.motion_val[1][xy + wrap + 1][1] = 0;
        }
        return;
    }

    C = s->current_picture.motion_val[0][xy - 1];
    A = s->current_picture.motion_val[0][xy - wrap];
    if(mv1)
        off = (s->mb_x == (s->mb_width - 1)) ? -1 : 2;
    else {
        //in 4-MV mode different blocks have different B predictor position
        switch(n){
        case 0:
            off = (s->mb_x > 0) ? -1 : 1;
            break;
        case 1:
            off = (s->mb_x == (s->mb_width - 1)) ? -1 : 1;
            break;
        case 2:
            off = 1;
            break;
        case 3:
            off = -1;
        }
    }
    B = s->current_picture.motion_val[0][xy - wrap + off];

    if(!s->first_slice_line || (n==2 || n==3)) { // predictor A is not out of bounds
        if(s->mb_width == 1) {
            px = A[0];
            py = A[1];
        } else {
            px = mid_pred(A[0], B[0], C[0]);
            py = mid_pred(A[1], B[1], C[1]);
        }
    } else if(s->mb_x || (n==1 || n==3)) { // predictor C is not out of bounds
        px = C[0];
        py = C[1];
    } else {
        px = py = 0;
    }
    /* Pullback MV as specified in 8.3.5.3.4 */
    {
        int qx, qy, X, Y;
        qx = (s->mb_x << 6) + ((n==1 || n==3) ? 32 : 0);
        qy = (s->mb_y << 6) + ((n==2 || n==3) ? 32 : 0);
        X = (s->mb_width << 6) - 4;
        Y = (s->mb_height << 6) - 4;
        if(mv1) {
            if(qx + px < -60) px = -60 - qx;
            if(qy + py < -60) py = -60 - qy;
        } else {
            if(qx + px < -28) px = -28 - qx;
            if(qy + py < -28) py = -28 - qy;
        }
        if(qx + px > X) px = X - qx;
        if(qy + py > Y) py = Y - qy;
    }
    /* Calculate hybrid prediction as specified in 8.3.5.3.5 */
    if((!s->first_slice_line || (n==2 || n==3)) && (s->mb_x || (n==1 || n==3))) {
        if(is_intra[xy - wrap])
            sum = FFABS(px) + FFABS(py);
        else
            sum = FFABS(px - A[0]) + FFABS(py - A[1]);
        if(sum > 32) {
            if(get_bits1(&s->gb)) {
                px = A[0];
                py = A[1];
            } else {
                px = C[0];
                py = C[1];
            }
        } else {
            if(is_intra[xy - 1])
                sum = FFABS(px) + FFABS(py);
            else
                sum = FFABS(px - C[0]) + FFABS(py - C[1]);
            if(sum > 32) {
                if(get_bits1(&s->gb)) {
                    px = A[0];
                    py = A[1];
                } else {
                    px = C[0];
                    py = C[1];
                }
            }
        }
    }
    /* store MV using signed modulus of MV range defined in 4.11 */
    s->mv[0][n][0] = s->current_picture.motion_val[0][xy][0] = ((px + dmv_x + r_x) & ((r_x << 1) - 1)) - r_x;
    s->mv[0][n][1] = s->current_picture.motion_val[0][xy][1] = ((py + dmv_y + r_y) & ((r_y << 1) - 1)) - r_y;
    if(mv1) { /* duplicate motion data for 1-MV block */
        s->current_picture.motion_val[0][xy + 1][0] = s->current_picture.motion_val[0][xy][0];
        s->current_picture.motion_val[0][xy + 1][1] = s->current_picture.motion_val[0][xy][1];
        s->current_picture.motion_val[0][xy + wrap][0] = s->current_picture.motion_val[0][xy][0];
        s->current_picture.motion_val[0][xy + wrap][1] = s->current_picture.motion_val[0][xy][1];
        s->current_picture.motion_val[0][xy + wrap + 1][0] = s->current_picture.motion_val[0][xy][0];
        s->current_picture.motion_val[0][xy + wrap + 1][1] = s->current_picture.motion_val[0][xy][1];
    }
}

/** Motion compensation for direct or interpolated blocks in B-frames
 */
static void vc1_interp_mc(VC1Context *v)
{
    MpegEncContext *s = &v->s;
    DSPContext *dsp = &v->s.dsp;
    uint8_t *srcY, *srcU, *srcV;
    int dxy, uvdxy, mx, my, uvmx, uvmy, src_x, src_y, uvsrc_x, uvsrc_y;

    if(!v->s.next_picture.data[0])return;

    mx = s->mv[1][0][0];
    my = s->mv[1][0][1];
    uvmx = (mx + ((mx & 3) == 3)) >> 1;
    uvmy = (my + ((my & 3) == 3)) >> 1;
    if(v->fastuvmc) {
        uvmx = uvmx + ((uvmx<0)?-(uvmx&1):(uvmx&1));
        uvmy = uvmy + ((uvmy<0)?-(uvmy&1):(uvmy&1));
    }
    srcY = s->next_picture.data[0];
    srcU = s->next_picture.data[1];
    srcV = s->next_picture.data[2];

    src_x = s->mb_x * 16 + (mx >> 2);
    src_y = s->mb_y * 16 + (my >> 2);
    uvsrc_x = s->mb_x * 8 + (uvmx >> 2);
    uvsrc_y = s->mb_y * 8 + (uvmy >> 2);

    if(v->profile != PROFILE_ADVANCED){
        src_x   = av_clip(  src_x, -16, s->mb_width  * 16);
        src_y   = av_clip(  src_y, -16, s->mb_height * 16);
        uvsrc_x = av_clip(uvsrc_x,  -8, s->mb_width  *  8);
        uvsrc_y = av_clip(uvsrc_y,  -8, s->mb_height *  8);
    }else{
        src_x   = av_clip(  src_x, -17, s->avctx->coded_width);
        src_y   = av_clip(  src_y, -18, s->avctx->coded_height + 1);
        uvsrc_x = av_clip(uvsrc_x,  -8, s->avctx->coded_width  >> 1);
        uvsrc_y = av_clip(uvsrc_y,  -8, s->avctx->coded_height >> 1);
    }

    srcY += src_y * s->linesize + src_x;
    srcU += uvsrc_y * s->uvlinesize + uvsrc_x;
    srcV += uvsrc_y * s->uvlinesize + uvsrc_x;

    /* for grayscale we should not try to read from unknown area */
    if(s->flags & CODEC_FLAG_GRAY) {
        srcU = s->edge_emu_buffer + 18 * s->linesize;
        srcV = s->edge_emu_buffer + 18 * s->linesize;
    }

    if(v->rangeredfrm
       || (unsigned)src_x > s->h_edge_pos - (mx&3) - 16
       || (unsigned)src_y > s->v_edge_pos - (my&3) - 16){
        uint8_t *uvbuf= s->edge_emu_buffer + 19 * s->linesize;

        srcY -= s->mspel * (1 + s->linesize);
        ff_emulated_edge_mc(s->edge_emu_buffer, srcY, s->linesize, 17+s->mspel*2, 17+s->mspel*2,
                            src_x - s->mspel, src_y - s->mspel, s->h_edge_pos, s->v_edge_pos);
        srcY = s->edge_emu_buffer;
        ff_emulated_edge_mc(uvbuf     , srcU, s->uvlinesize, 8+1, 8+1,
                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);
        ff_emulated_edge_mc(uvbuf + 16, srcV, s->uvlinesize, 8+1, 8+1,
                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);
        srcU = uvbuf;
        srcV = uvbuf + 16;
        /* if we deal with range reduction we need to scale source blocks */
        if(v->rangeredfrm) {
            int i, j;
            uint8_t *src, *src2;

            src = srcY;
            for(j = 0; j < 17 + s->mspel*2; j++) {
                for(i = 0; i < 17 + s->mspel*2; i++) src[i] = ((src[i] - 128) >> 1) + 128;
                src += s->linesize;
            }
            src = srcU; src2 = srcV;
            for(j = 0; j < 9; j++) {
                for(i = 0; i < 9; i++) {
                    src[i] = ((src[i] - 128) >> 1) + 128;
                    src2[i] = ((src2[i] - 128) >> 1) + 128;
                }
                src += s->uvlinesize;
                src2 += s->uvlinesize;
            }
        }
        srcY += s->mspel * (1 + s->linesize);
    }

    mx >>= 1;
    my >>= 1;
    dxy = ((my & 1) << 1) | (mx & 1);

    dsp->avg_pixels_tab[0][dxy](s->dest[0], srcY, s->linesize, 16);

    if(s->flags & CODEC_FLAG_GRAY) return;
    /* Chroma MC always uses qpel blilinear */
    uvdxy = ((uvmy & 3) << 2) | (uvmx & 3);
    uvmx = (uvmx&3)<<1;
    uvmy = (uvmy&3)<<1;
    dsp->avg_h264_chroma_pixels_tab[0](s->dest[1], srcU, s->uvlinesize, 8, uvmx, uvmy);
    dsp->avg_h264_chroma_pixels_tab[0](s->dest[2], srcV, s->uvlinesize, 8, uvmx, uvmy);
}

static av_always_inline int scale_mv(int value, int bfrac, int inv, int qs)
{
    int n = bfrac;

#if B_FRACTION_DEN==256
    if(inv)
        n -= 256;
    if(!qs)
        return 2 * ((value * n + 255) >> 9);
    return (value * n + 128) >> 8;
#else
    if(inv)
        n -= B_FRACTION_DEN;
    if(!qs)
        return 2 * ((value * n + B_FRACTION_DEN - 1) / (2 * B_FRACTION_DEN));
    return (value * n + B_FRACTION_DEN/2) / B_FRACTION_DEN;
#endif
}

/** Reconstruct motion vector for B-frame and do motion compensation
 */
static inline void vc1_b_mc(VC1Context *v, int dmv_x[2], int dmv_y[2], int direct, int mode)
{
    if(v->use_ic) {
        v->mv_mode2 = v->mv_mode;
        v->mv_mode = MV_PMODE_INTENSITY_COMP;
    }
    if(direct) {
        vc1_mc_1mv(v, 0);
        vc1_interp_mc(v);
        if(v->use_ic) v->mv_mode = v->mv_mode2;
        return;
    }
    if(mode == BMV_TYPE_INTERPOLATED) {
        vc1_mc_1mv(v, 0);
        vc1_interp_mc(v);
        if(v->use_ic) v->mv_mode = v->mv_mode2;
        return;
    }

    if(v->use_ic && (mode == BMV_TYPE_BACKWARD)) v->mv_mode = v->mv_mode2;
    vc1_mc_1mv(v, (mode == BMV_TYPE_BACKWARD));
    if(v->use_ic) v->mv_mode = v->mv_mode2;
}

static inline void vc1_pred_b_mv(VC1Context *v, int dmv_x[2], int dmv_y[2], int direct, int mvtype)
{
    MpegEncContext *s = &v->s;
    int xy, wrap, off = 0;
    int16_t *A, *B, *C;
    int px, py;
    int sum;
    int r_x, r_y;
    const uint8_t *is_intra = v->mb_type[0];

    r_x = v->range_x;
    r_y = v->range_y;
    /* scale MV difference to be quad-pel */
    dmv_x[0] <<= 1 - s->quarter_sample;
    dmv_y[0] <<= 1 - s->quarter_sample;
    dmv_x[1] <<= 1 - s->quarter_sample;
    dmv_y[1] <<= 1 - s->quarter_sample;

    wrap = s->b8_stride;
    xy = s->block_index[0];

    if(s->mb_intra) {
        s->current_picture.motion_val[0][xy][0] =
        s->current_picture.motion_val[0][xy][1] =
        s->current_picture.motion_val[1][xy][0] =
        s->current_picture.motion_val[1][xy][1] = 0;
        return;
    }
    s->mv[0][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 0, s->quarter_sample);
    s->mv[0][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 0, s->quarter_sample);
    s->mv[1][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 1, s->quarter_sample);
    s->mv[1][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 1, s->quarter_sample);

    /* Pullback predicted motion vectors as specified in 8.4.5.4 */
    s->mv[0][0][0] = av_clip(s->mv[0][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));
    s->mv[0][0][1] = av_clip(s->mv[0][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));
    s->mv[1][0][0] = av_clip(s->mv[1][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));
    s->mv[1][0][1] = av_clip(s->mv[1][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));
    if(direct) {
        s->current_picture.motion_val[0][xy][0] = s->mv[0][0][0];
        s->current_picture.motion_val[0][xy][1] = s->mv[0][0][1];
        s->current_picture.motion_val[1][xy][0] = s->mv[1][0][0];
        s->current_picture.motion_val[1][xy][1] = s->mv[1][0][1];
        return;
    }

    if((mvtype == BMV_TYPE_FORWARD) || (mvtype == BMV_TYPE_INTERPOLATED)) {
        C = s->current_picture.motion_val[0][xy - 2];
        A = s->current_picture.motion_val[0][xy - wrap*2];
        off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;
        B = s->current_picture.motion_val[0][xy - wrap*2 + off];

        if(!s->mb_x) C[0] = C[1] = 0;
        if(!s->first_slice_line) { // predictor A is not out of bounds
            if(s->mb_width == 1) {
                px = A[0];
                py = A[1];
            } else {
                px = mid_pred(A[0], B[0], C[0]);
                py = mid_pred(A[1], B[1], C[1]);
            }
        } else if(s->mb_x) { // predictor C is not out of bounds
            px = C[0];
            py = C[1];
        } else {
            px = py = 0;
        }
        /* Pullback MV as specified in 8.3.5.3.4 */
        {
            int qx, qy, X, Y;
            if(v->profile < PROFILE_ADVANCED) {
                qx = (s->mb_x << 5);
                qy = (s->mb_y << 5);
                X = (s->mb_width << 5) - 4;
                Y = (s->mb_height << 5) - 4;
                if(qx + px < -28) px = -28 - qx;
                if(qy + py < -28) py = -28 - qy;
                if(qx + px > X) px = X - qx;
                if(qy + py > Y) py = Y - qy;
            } else {
                qx = (s->mb_x << 6);
                qy = (s->mb_y << 6);
                X = (s->mb_width << 6) - 4;
                Y = (s->mb_height << 6) - 4;
                if(qx + px < -60) px = -60 - qx;
                if(qy + py < -60) py = -60 - qy;
                if(qx + px > X) px = X - qx;
                if(qy + py > Y) py = Y - qy;
            }
        }
        /* Calculate hybrid prediction as specified in 8.3.5.3.5 */
        if(0 && !s->first_slice_line && s->mb_x) {
            if(is_intra[xy - wrap])
                sum = FFABS(px) + FFABS(py);
            else
                sum = FFABS(px - A[0]) + FFABS(py - A[1]);
            if(sum > 32) {
                if(get_bits1(&s->gb)) {
                    px = A[0];
                    py = A[1];
                } else {
                    px = C[0];
                    py = C[1];
                }
            } else {
                if(is_intra[xy - 2])
                    sum = FFABS(px) + FFABS(py);
                else
                    sum = FFABS(px - C[0]) + FFABS(py - C[1]);
                if(sum > 32) {
                    if(get_bits1(&s->gb)) {
                        px = A[0];
                        py = A[1];
                    } else {
                        px = C[0];
                        py = C[1];
                    }
                }