void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
                            int lowres_flag, int is_mpeg12)
{
    const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;

    if (CONFIG_XVMC &&
        s->avctx->hwaccel && s->avctx->hwaccel->decode_mb) {
        s->avctx->hwaccel->decode_mb(s);//xvmc uses pblocks
        return;
    }

    if(s->avctx->debug&FF_DEBUG_DCT_COEFF) {
       /* print DCT coefficients */
       int i,j;
       av_log(s->avctx, AV_LOG_DEBUG, "DCT coeffs of MB at %dx%d:\n", s->mb_x, s->mb_y);
       for(i=0; i<6; i++){
           for(j=0; j<64; j++){
               av_log(s->avctx, AV_LOG_DEBUG, "%5d",
                      block[i][s->idsp.idct_permutation[j]]);
           }
           av_log(s->avctx, AV_LOG_DEBUG, "\n");
       }
    }

    s->current_picture.qscale_table[mb_xy] = s->qscale;

    /* update DC predictors for P macroblocks */
    if (!s->mb_intra) {
        if (!is_mpeg12 && (s->h263_pred || s->h263_aic)) {
            if(s->mbintra_table[mb_xy])
                ff_clean_intra_table_entries(s);
        } else {
            s->last_dc[0] =
            s->last_dc[1] =
            s->last_dc[2] = 128 << s->intra_dc_precision;
        }
    }
    else if (!is_mpeg12 && (s->h263_pred || s->h263_aic))
        s->mbintra_table[mb_xy]=1;

    if ((s->avctx->flags & AV_CODEC_FLAG_PSNR) || s->frame_skip_threshold || s->frame_skip_factor ||
        !(s->encoding && (s->intra_only || s->pict_type == AV_PICTURE_TYPE_B) &&
          s->avctx->mb_decision != FF_MB_DECISION_RD)) { // FIXME precalc
        uint8_t *dest_y, *dest_cb, *dest_cr;
        int dct_linesize, dct_offset;
        op_pixels_func (*op_pix)[4];
        qpel_mc_func (*op_qpix)[16];
        const int linesize   = s->current_picture.f->linesize[0]; //not s->linesize as this would be wrong for field pics
        const int uvlinesize = s->current_picture.f->linesize[1];
        const int readable= s->pict_type != AV_PICTURE_TYPE_B || s->encoding || s->avctx->draw_horiz_band || lowres_flag;
        const int block_size= lowres_flag ? 8>>s->avctx->lowres : 8;

        /* avoid copy if macroblock skipped in last frame too */
        /* skip only during decoding as we might trash the buffers during encoding a bit */
        if(!s->encoding){
            uint8_t *mbskip_ptr = &s->mbskip_table[mb_xy];

            if (s->mb_skipped) {
                s->mb_skipped= 0;
                av_assert2(s->pict_type!=AV_PICTURE_TYPE_I);
                *mbskip_ptr = 1;
            } else if(!s->current_picture.reference) {
                *mbskip_ptr = 1;
            } else{
                *mbskip_ptr = 0; /* not skipped */
            }
        }

        dct_linesize = linesize << s->interlaced_dct;
        dct_offset   = s->interlaced_dct ? linesize : linesize * block_size;

        if(readable){
            dest_y=  s->dest[0];
            dest_cb= s->dest[1];
            dest_cr= s->dest[2];
        }else{
            dest_y = s->sc.b_scratchpad;
            dest_cb= s->sc.b_scratchpad+16*linesize;
            dest_cr= s->sc.b_scratchpad+32*linesize;
        }

        if (!s->mb_intra) {
            /* motion handling */
            /* decoding or more than one mb_type (MC was already done otherwise) */
            if(!s->encoding){

                if(HAVE_THREADS && s->avctx->active_thread_type&FF_THREAD_FRAME) {
                    if (s->mv_dir & MV_DIR_FORWARD) {
                        ff_thread_await_progress(&s->last_picture_ptr->tf,
                                                 lowest_referenced_row(s, 0),
                                                 0);
                    }
                    if (s->mv_dir & MV_DIR_BACKWARD) {
                        ff_thread_await_progress(&s->next_picture_ptr->tf,
                                                 lowest_referenced_row(s, 1),
                                                 0);
                    }
                }

                if(lowres_flag){
                    h264_chroma_mc_func *op_pix = s->h264chroma.put_h264_chroma_pixels_tab;

                    if (s->mv_dir & MV_DIR_FORWARD) {
                        MPV_motion_lowres(s, dest_y, dest_cb, dest_cr, 0, s->last_picture.f->data, op_pix);
                        op_pix = s->h264chroma.avg_h264_chroma_pixels_tab;
                    }
                    if (s->mv_dir & MV_DIR_BACKWARD) {
                        MPV_motion_lowres(s, dest_y, dest_cb, dest_cr, 1, s->next_picture.f->data, op_pix);
                    }
                }else{
                    op_qpix = s->me.qpel_put;
                    if ((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
                        op_pix = s->hdsp.put_pixels_tab;
                    }else{
                        op_pix = s->hdsp.put_no_rnd_pixels_tab;
                    }
                    if (s->mv_dir & MV_DIR_FORWARD) {
                        ff_mpv_motion(s, dest_y, dest_cb, dest_cr, 0, s->last_picture.f->data, op_pix, op_qpix);
                        op_pix = s->hdsp.avg_pixels_tab;
                        op_qpix= s->me.qpel_avg;
                    }
                    if (s->mv_dir & MV_DIR_BACKWARD) {
                        ff_mpv_motion(s, dest_y, dest_cb, dest_cr, 1, s->next_picture.f->data, op_pix, op_qpix);
                    }
                }
            }

            /* skip dequant / idct if we are really late ;) */
            if(s->avctx->skip_idct){
                if(  (s->avctx->skip_idct >= AVDISCARD_NONREF && s->pict_type == AV_PICTURE_TYPE_B)
                   ||(s->avctx->skip_idct >= AVDISCARD_NONKEY && s->pict_type != AV_PICTURE_TYPE_I)
                   || s->avctx->skip_idct >= AVDISCARD_ALL)
                    goto skip_idct;
            }

            /* add dct residue */
            if(s->encoding || !(   s->msmpeg4_version || s->codec_id==AV_CODEC_ID_MPEG1VIDEO || s->codec_id==AV_CODEC_ID_MPEG2VIDEO
                                || (s->codec_id==AV_CODEC_ID_MPEG4 && !s->mpeg_quant))){
                add_dequant_dct(s, block[0], 0, dest_y                          , dct_linesize, s->qscale);
                add_dequant_dct(s, block[1], 1, dest_y              + block_size, dct_linesize, s->qscale);
                add_dequant_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize, s->qscale);
                add_dequant_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize, s->qscale);

                if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
                    if (s->chroma_y_shift){
                        add_dequant_dct(s, block[4], 4, dest_cb, uvlinesize, s->chroma_qscale);
                        add_dequant_dct(s, block[5], 5, dest_cr, uvlinesize, s->chroma_qscale);
                    }else{
                        dct_linesize >>= 1;
                        dct_offset >>=1;
                        add_dequant_dct(s, block[4], 4, dest_cb,              dct_linesize, s->chroma_qscale);
                        add_dequant_dct(s, block[5], 5, dest_cr,              dct_linesize, s->chroma_qscale);
                        add_dequant_dct(s, block[6], 6, dest_cb + dct_offset, dct_linesize, s->chroma_qscale);
                        add_dequant_dct(s, block[7], 7, dest_cr + dct_offset, dct_linesize, s->chroma_qscale);
                    }
                }
            } else if(is_mpeg12 || (s->codec_id != AV_CODEC_ID_WMV2)){
                add_dct(s, block[0], 0, dest_y                          , dct_linesize);
                add_dct(s, block[1], 1, dest_y              + block_size, dct_linesize);
                add_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize);
                add_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize);

                if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
                    if(s->chroma_y_shift){//Chroma420
                        add_dct(s, block[4], 4, dest_cb, uvlinesize);
                        add_dct(s, block[5], 5, dest_cr, uvlinesize);
                    }else{
                        dct_linesize = uvlinesize << s->interlaced_dct;
                        dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;

                        add_dct(s, block[4], 4, dest_cb, dct_linesize);
                        add_dct(s, block[5], 5, dest_cr, dct_linesize);
                        add_dct(s, block[6], 6, dest_cb+dct_offset, dct_linesize);
                        add_dct(s, block[7], 7, dest_cr+dct_offset, dct_linesize);
                        if(!s->chroma_x_shift){//Chroma444
                            add_dct(s, block[8], 8, dest_cb+block_size, dct_linesize);
                            add_dct(s, block[9], 9, dest_cr+block_size, dct_linesize);
                            add_dct(s, block[10], 10, dest_cb+block_size+dct_offset, dct_linesize);
                            add_dct(s, block[11], 11, dest_cr+block_size+dct_offset, dct_linesize);
                        }
                    }
                }//fi gray
            }
            else if (CONFIG_WMV2_DECODER || CONFIG_WMV2_ENCODER) {
                ff_wmv2_add_mb(s, block, dest_y, dest_cb, dest_cr);
            }
        } else {
            /* Only MPEG-4 Simple Studio Profile is supported in > 8-bit mode.
               TODO: Integrate 10-bit properly into mpegvideo.c so that ER works properly */
            if (s->avctx->bits_per_raw_sample > 8){
                const int act_block_size = block_size * 2;
                s->idsp.idct_put(dest_y,                           dct_linesize, (int16_t*)(*s->block32)[0]);
                s->idsp.idct_put(dest_y              + act_block_size, dct_linesize, (int16_t*)(*s->block32)[1]);
                s->idsp.idct_put(dest_y + dct_offset,              dct_linesize, (int16_t*)(*s->block32)[2]);
                s->idsp.idct_put(dest_y + dct_offset + act_block_size, dct_linesize, (int16_t*)(*s->block32)[3]);

                dct_linesize = uvlinesize << s->interlaced_dct;
                dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;

                s->idsp.idct_put(dest_cb,              dct_linesize, (int16_t*)(*s->block32)[4]);
                s->idsp.idct_put(dest_cr,              dct_linesize, (int16_t*)(*s->block32)[5]);
                s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, (int16_t*)(*s->block32)[6]);
                s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, (int16_t*)(*s->block32)[7]);
                if(!s->chroma_x_shift){//Chroma444
                    s->idsp.idct_put(dest_cb + act_block_size,              dct_linesize, (int16_t*)(*s->block32)[8]);
                    s->idsp.idct_put(dest_cr + act_block_size,              dct_linesize, (int16_t*)(*s->block32)[9]);
                    s->idsp.idct_put(dest_cb + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[10]);
                    s->idsp.idct_put(dest_cr + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[11]);
                }
            }
            /* dct only in intra block */
            else if(s->encoding || !(s->codec_id==AV_CODEC_ID_MPEG1VIDEO || s->codec_id==AV_CODEC_ID_MPEG2VIDEO)){
                put_dct(s, block[0], 0, dest_y                          , dct_linesize, s->qscale);
                put_dct(s, block[1], 1, dest_y              + block_size, dct_linesize, s->qscale);
                put_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize, s->qscale);
                put_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize, s->qscale);

                if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
                    if(s->chroma_y_shift){
                        put_dct(s, block[4], 4, dest_cb, uvlinesize, s->chroma_qscale);
                        put_dct(s, block[5], 5, dest_cr, uvlinesize, s->chroma_qscale);
                    }else{
                        dct_offset >>=1;
                        dct_linesize >>=1;
                        put_dct(s, block[4], 4, dest_cb,              dct_linesize, s->chroma_qscale);
                        put_dct(s, block[5], 5, dest_cr,              dct_linesize, s->chroma_qscale);
                        put_dct(s, block[6], 6, dest_cb + dct_offset, dct_linesize, s->chroma_qscale);
                        put_dct(s, block[7], 7, dest_cr + dct_offset, dct_linesize, s->chroma_qscale);
                    }
                }
            }else{
                s->idsp.idct_put(dest_y,                           dct_linesize, block[0]);
                s->idsp.idct_put(dest_y              + block_size, dct_linesize, block[1]);
                s->idsp.idct_put(dest_y + dct_offset,              dct_linesize, block[2]);
                s->idsp.idct_put(dest_y + dct_offset + block_size, dct_linesize, block[3]);

                if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
                    if(s->chroma_y_shift){
                        s->idsp.idct_put(dest_cb, uvlinesize, block[4]);
                        s->idsp.idct_put(dest_cr, uvlinesize, block[5]);
                    }else{

                        dct_linesize = uvlinesize << s->interlaced_dct;
                        dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;

                        s->idsp.idct_put(dest_cb,              dct_linesize, block[4]);
                        s->idsp.idct_put(dest_cr,              dct_linesize, block[5]);
                        s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, block[6]);
                        s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, block[7]);
                        if(!s->chroma_x_shift){//Chroma444
                            s->idsp.idct_put(dest_cb + block_size,              dct_linesize, block[8]);
                            s->idsp.idct_put(dest_cr + block_size,              dct_linesize, block[9]);
                            s->idsp.idct_put(dest_cb + block_size + dct_offset, dct_linesize, block[10]);
                            s->idsp.idct_put(dest_cr + block_size + dct_offset, dct_linesize, block[11]);
                        }
                    }
                }//gray
            }
        }
skip_idct:
        if(!readable){
            s->hdsp.put_pixels_tab[0][0](s->dest[0], dest_y ,   linesize,16);
            if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
                s->hdsp.put_pixels_tab[s->chroma_x_shift][0](s->dest[1], dest_cb, uvlinesize,16 >> s->chroma_y_shift);
                s->hdsp.put_pixels_tab[s->chroma_x_shift][0](s->dest[2], dest_cr, uvlinesize,16 >> s->chroma_y_shift);
            }
        }
    }
}

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