}    switch(s->pict_type) {    default:    case I_TYPE:        if (get_bits1(&s->gb) == 0) {            if (get_bits1(&s->gb) == 0){                av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);                return -1;            }            mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;        } else {            mb_type = MB_TYPE_INTRA;        }        break;    case P_TYPE:        mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);        if (mb_type < 0){            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);            return -1;        }        mb_type = ptype2mb_type[ mb_type ];        break;    case B_TYPE:        mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);        if (mb_type < 0){            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);            return -1;        }        mb_type = btype2mb_type[ mb_type ];        break;    }    dprintf("mb_type=%x\n", mb_type);//    motion_type = 0; /* avoid warning */    if (IS_INTRA(mb_type)) {        s->dsp.clear_blocks(s->block[0]);            if(!s->chroma_y_shift){            s->dsp.clear_blocks(s->block[6]);        }        /* compute dct type */        if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?            !s->frame_pred_frame_dct) {        s->interlaced_dct = get_bits1(&s->gb);    }        if (IS_QUANT(mb_type))        s->qscale = get_qscale(s);                if (s->concealment_motion_vectors) {            /* just parse them */            if (s->picture_structure != PICT_FRAME)                 skip_bits1(&s->gb); /* field select */                        s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);            s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);            skip_bits1(&s->gb); /* marker */        }else            memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */        s->mb_intra = 1;#ifdef HAVE_XVMC        //one 1 we memcpy blocks in xvmcvideo        if(s->avctx->xvmc_acceleration > 1){            XVMC_pack_pblocks(s,-1);//inter are always full blocks            if(s->swap_uv){                exchange_uv(s);            }        }#endif        if (s->codec_id == CODEC_ID_MPEG2VIDEO) {            if(s->flags2 & CODEC_FLAG2_FAST){                for(i=0;i<6;i++) {                    mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);                }            }else{            for(i=0;i<mb_block_count;i++) {                if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)                    return -1;            }            }    } else {            for(i=0;i<6;i++) {                if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)                    return -1;            }        }    } else {        if (mb_type & MB_TYPE_ZERO_MV){            assert(mb_type & MB_TYPE_CBP);            /* compute dct type */            if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?                !s->frame_pred_frame_dct) {                s->interlaced_dct = get_bits1(&s->gb);    }            if (IS_QUANT(mb_type))                s->qscale = get_qscale(s);        s->mv_dir = MV_DIR_FORWARD;            if(s->picture_structure == PICT_FRAME)        s->mv_type = MV_TYPE_16X16;            else{                s->mv_type = MV_TYPE_FIELD;                mb_type |= MB_TYPE_INTERLACED;                s->field_select[0][0]= s->picture_structure - 1;            }        s->last_mv[0][0][0] = 0;        s->last_mv[0][0][1] = 0;        s->last_mv[0][1][0] = 0;        s->last_mv[0][1][1] = 0;        s->mv[0][0][0] = 0;        s->mv[0][0][1] = 0;        }else{            assert(mb_type & MB_TYPE_L0L1);//FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED            /* get additionnal motion vector type */            if (s->frame_pred_frame_dct)                 motion_type = MT_FRAME;            else{                motion_type = get_bits(&s->gb, 2);            }            /* compute dct type */            if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?                !s->frame_pred_frame_dct && HAS_CBP(mb_type)) {                s->interlaced_dct = get_bits1(&s->gb);            }            if (IS_QUANT(mb_type))                s->qscale = get_qscale(s);        /* motion vectors */        s->mv_dir = 0;        for(i=0;i<2;i++) {                if (USES_LIST(mb_type, i)) {                s->mv_dir |= (MV_DIR_FORWARD >> i);                dprintf("motion_type=%d\n", motion_type);                switch(motion_type) {                case MT_FRAME: /* or MT_16X8 */                    if (s->picture_structure == PICT_FRAME) {                        /* MT_FRAME */                            mb_type |= MB_TYPE_16x16;                         s->mv_type = MV_TYPE_16X16;                            s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);                            s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);                            /* full_pel: only for mpeg1 */                            if (s->full_pel[i]){                                s->mv[i][0][0] <<= 1;                                s->mv[i][0][1] <<= 1;                        }                    } else {                        /* MT_16X8 */                            mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;                         s->mv_type = MV_TYPE_16X8;                        for(j=0;j<2;j++) {                            s->field_select[i][j] = get_bits1(&s->gb);                            for(k=0;k<2;k++) {                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],                                                         s->last_mv[i][j][k]);                                s->last_mv[i][j][k] = val;                                s->mv[i][j][k] = val;                            }                        }                    }                    break;                case MT_FIELD:                    s->mv_type = MV_TYPE_FIELD;                    if (s->picture_structure == PICT_FRAME) {                            mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;                         for(j=0;j<2;j++) {                            s->field_select[i][j] = get_bits1(&s->gb);                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],                                                     s->last_mv[i][j][0]);                            s->last_mv[i][j][0] = val;                            s->mv[i][j][0] = val;                            dprintf("fmx=%d\n", val);                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],                                                     s->last_mv[i][j][1] >> 1);                            s->last_mv[i][j][1] = val << 1;                            s->mv[i][j][1] = val;                            dprintf("fmy=%d\n", val);                        }                    } else {                            mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;                         s->field_select[i][0] = get_bits1(&s->gb);                        for(k=0;k<2;k++) {                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],                                                     s->last_mv[i][0][k]);                            s->last_mv[i][0][k] = val;                            s->last_mv[i][1][k] = val;                            s->mv[i][0][k] = val;                        }                    }                    break;                case MT_DMV:                    {                        int dmx, dmy, mx, my, m;                        mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],                                                 s->last_mv[i][0][0]);                        s->last_mv[i][0][0] = mx;                        s->last_mv[i][1][0] = mx;                        dmx = get_dmv(s);                        my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],                                                 s->last_mv[i][0][1] >> 1);                        dmy = get_dmv(s);                        s->mv_type = MV_TYPE_DMV;                            s->last_mv[i][0][1] = my << 1;                            s->last_mv[i][1][1] = my << 1;                            s->mv[i][0][0] = mx;                            s->mv[i][0][1] = my;                            s->mv[i][1][0] = mx;//not used                            s->mv[i][1][1] = my;//not used                            if (s->picture_structure == PICT_FRAME) {                                mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;                                 //m = 1 + 2 * s->top_field_first;                            m = s->top_field_first ? 1 : 3;                            /* top -> top pred */                                s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;                                s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;                            m = 4 - m;                            s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;                            s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;                        } else {                                mb_type |= MB_TYPE_16x16;                                s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;                                s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;                                if(s->picture_structure == PICT_TOP_FIELD)                                    s->mv[i][2][1]--;                                else                                     s->mv[i][2][1]++;                        }                    }                    break;                    default:                        av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);                        return -1;                }            }        }    }        s->mb_intra = 0;        if (HAS_CBP(mb_type)) {            s->dsp.clear_blocks(s->block[0]);                    if(!s->chroma_y_shift){                s->dsp.clear_blocks(s->block[6]);            }            cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);            if (cbp < 0 || ((cbp == 0) && (s->chroma_format < 2)) ){                av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);            return -1;        }            if(mb_block_count > 6){	         cbp<<= mb_block_count-6;		 cbp |= get_bits(&s->gb, mb_block_count-6);            }#ifdef HAVE_XVMC            //on 1 we memcpy blocks in xvmcvideo            if(s->avctx->xvmc_acceleration > 1){                XVMC_pack_pblocks(s,cbp);                if(s->swap_uv){                    exchange_uv(s);                }            }    #endif            if (s->codec_id == CODEC_ID_MPEG2VIDEO) {                if(s->flags2 & CODEC_FLAG2_FAST){                    for(i=0;i<6;i++) {                        if(cbp & 32) {                            mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);                        } else {                            s->block_last_index[i] = -1;                        }                        cbp+=cbp;                    }                }else{                cbp<<= 12-mb_block_count;                for(i=0;i<mb_block_count;i++) {                    if ( cbp & (1<<11) ) {                        if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)                            return -1;                    } else {                        s->block_last_index[i] = -1;                    }                    cbp+=cbp;            }                }            } else {                if(s->flags2 & CODEC_FLAG2_FAST){                    for(i=0;i<6;i++) {                        if (cbp & 32) {                            mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);                        } else {                            s->block_last_index[i] = -1;                        }                        cbp+=cbp;                    }    } else {        for(i=0;i<6;i++) {                if (cbp & 32) {                        if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)                    return -1;            } else {                s->block_last_index[i] = -1;            }                cbp+=cbp;            }        }            }        }else{            for(i=0;i<12;i++)                s->block_last_index[i] = -1;        }    }    s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;    return 0;}/* as h263, but only 17 codes */static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred){    int code, sign, val, l, shift;    code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);    if (code == 0) {        return pred;    }    if (code < 0) {        return 0xffff;    }    sign = get_bits1(&s->gb);    shift = fcode - 1;    val = code;    if (shift) {        val = (val - 1) << shift;        val |= get_bits(&s->gb, shift);    val++;    }    if (sign)        val = -val;    val += pred;        /* modulo decoding */    l= INT_BIT - 5 - shift;    val = (val<<l)>>l;