motion_est.c

ffmpeg的完整源代码和作者自己写的文档。不但有在Linux的工程哦

            assert(field_select1==0 ||field_select1==1);
            init_interlaced_ref(s, 0);

            if(p_type){
                s->p_field_select_table[0][mb_xy]= field_select0;
                s->p_field_select_table[1][mb_xy]= field_select1;
                *(uint32_t*)s->p_field_mv_table[0][field_select0][mb_xy]= *(uint32_t*)p->motion_val[0][xy ];
                *(uint32_t*)s->p_field_mv_table[1][field_select1][mb_xy]= *(uint32_t*)p->motion_val[0][xy2];
                s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_INTER_I;
            }else{
                s->b_field_select_table[0][0][mb_xy]= field_select0;
                s->b_field_select_table[0][1][mb_xy]= field_select1;
                *(uint32_t*)s->b_field_mv_table[0][0][field_select0][mb_xy]= *(uint32_t*)p->motion_val[0][xy ];
                *(uint32_t*)s->b_field_mv_table[0][1][field_select1][mb_xy]= *(uint32_t*)p->motion_val[0][xy2];
                s->mb_type[mb_xy]= CANDIDATE_MB_TYPE_FORWARD_I;
            }

            x= p->motion_val[0][xy ][0];
            y= p->motion_val[0][xy ][1];
            d = cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 8, field_select0, 0, cmpf, chroma_cmpf, flags);
            x= p->motion_val[0][xy2][0];
            y= p->motion_val[0][xy2][1];
            d+= cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 8, field_select1, 1, cmpf, chroma_cmpf, flags);
        }
        if(USES_LIST(mb_type, 1)){
            int field_select0= p->ref_index[1][xy ];
            int field_select1= p->ref_index[1][xy2];
            assert(field_select0==0 ||field_select0==1);
            assert(field_select1==0 ||field_select1==1);
            init_interlaced_ref(s, 2);

            s->b_field_select_table[1][0][mb_xy]= field_select0;
            s->b_field_select_table[1][1][mb_xy]= field_select1;
            *(uint32_t*)s->b_field_mv_table[1][0][field_select0][mb_xy]= *(uint32_t*)p->motion_val[1][xy ];
            *(uint32_t*)s->b_field_mv_table[1][1][field_select1][mb_xy]= *(uint32_t*)p->motion_val[1][xy2];
            if(USES_LIST(mb_type, 0)){
                s->mb_type[mb_xy]= CANDIDATE_MB_TYPE_BIDIR_I;
            }else{
                s->mb_type[mb_xy]= CANDIDATE_MB_TYPE_BACKWARD_I;
            }

            x= p->motion_val[1][xy ][0];
            y= p->motion_val[1][xy ][1];
            d = cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 8, field_select0+2, 0, cmpf, chroma_cmpf, flags);
            x= p->motion_val[1][xy2][0];
            y= p->motion_val[1][xy2][1];
            d+= cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 8, field_select1+2, 1, cmpf, chroma_cmpf, flags);
            //FIXME bidir scores
        }
        c->stride>>=1;
        c->uvstride>>=1;
    }else if(IS_8X8(mb_type)){
        if(!(s->flags & CODEC_FLAG_4MV)){
            av_log(c->avctx, AV_LOG_ERROR, "4MV macroblock selected but 4MV encoding disabled\n");
            return INT_MAX/2;
        }
        cmpf= s->dsp.sse[1];
        chroma_cmpf= s->dsp.sse[1];
        init_mv4_ref(c);
        for(i=0; i<4; i++){
            xy= s->block_index[i];
            x= p->motion_val[0][xy][0];
            y= p->motion_val[0][xy][1];
            d+= cmp(s, x>>shift, y>>shift, x&mask, y&mask, 1, 8, i, i, cmpf, chroma_cmpf, flags);
        }
        s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_INTER4V;
    }else{
        if(USES_LIST(mb_type, 0)){
            if(p_type){
                *(uint32_t*)s->p_mv_table[mb_xy]= *(uint32_t*)p->motion_val[0][xy];
                s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_INTER;
            }else if(USES_LIST(mb_type, 1)){
                *(uint32_t*)s->b_bidir_forw_mv_table[mb_xy]= *(uint32_t*)p->motion_val[0][xy];
                *(uint32_t*)s->b_bidir_back_mv_table[mb_xy]= *(uint32_t*)p->motion_val[1][xy];
                s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_BIDIR;
            }else{
                *(uint32_t*)s->b_forw_mv_table[mb_xy]= *(uint32_t*)p->motion_val[0][xy];
                s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_FORWARD;
            }
            x= p->motion_val[0][xy][0];
            y= p->motion_val[0][xy][1];
            d = cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 16, 0, 0, cmpf, chroma_cmpf, flags);
        }else if(USES_LIST(mb_type, 1)){
            *(uint32_t*)s->b_back_mv_table[mb_xy]= *(uint32_t*)p->motion_val[1][xy];
            s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_BACKWARD;

            x= p->motion_val[1][xy][0];
            y= p->motion_val[1][xy][1];
            d = cmp(s, x>>shift, y>>shift, x&mask, y&mask, 0, 16, 2, 0, cmpf, chroma_cmpf, flags);
        }else
            s->mb_type[mb_xy]=CANDIDATE_MB_TYPE_INTRA;
    }
    return d;
}

void ff_estimate_p_frame_motion(MpegEncContext * s,
                                int mb_x, int mb_y)
{
    MotionEstContext * const c= &s->me;
    uint8_t *pix, *ppix;
    int sum, mx, my, dmin;
    int varc;            ///< the variance of the block (sum of squared (p[y][x]-average))
    int vard;            ///< sum of squared differences with the estimated motion vector
    int P[10][2];
    const int shift= 1+s->quarter_sample;
    int mb_type=0;
    Picture * const pic= &s->current_picture;

    init_ref(c, s->new_picture.data, s->last_picture.data, NULL, 16*mb_x, 16*mb_y, 0);

    assert(s->quarter_sample==0 || s->quarter_sample==1);
    assert(s->linesize == c->stride);
    assert(s->uvlinesize == c->uvstride);

    c->penalty_factor    = get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_cmp);
    c->sub_penalty_factor= get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_sub_cmp);
    c->mb_penalty_factor = get_penalty_factor(s->lambda, s->lambda2, c->avctx->mb_cmp);
    c->current_mv_penalty= c->mv_penalty[s->f_code] + MAX_MV;

    get_limits(s, 16*mb_x, 16*mb_y);
    c->skip=0;

    /* intra / predictive decision */
    pix = c->src[0][0];
    sum = s->dsp.pix_sum(pix, s->linesize);
    varc = s->dsp.pix_norm1(pix, s->linesize) - (((unsigned)(sum*sum))>>8) + 500;

    pic->mb_mean[s->mb_stride * mb_y + mb_x] = (sum+128)>>8;
    pic->mb_var [s->mb_stride * mb_y + mb_x] = (varc+128)>>8;
    c->mb_var_sum_temp += (varc+128)>>8;

    if(c->avctx->me_threshold){
        vard= check_input_motion(s, mb_x, mb_y, 1);

        if((vard+128)>>8 < c->avctx->me_threshold){
            int p_score= FFMIN(vard, varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*100);
            int i_score= varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*20;
            pic->mc_mb_var[s->mb_stride * mb_y + mb_x] = (vard+128)>>8;
            c->mc_mb_var_sum_temp += (vard+128)>>8;
            c->scene_change_score+= ff_sqrt(p_score) - ff_sqrt(i_score);
            return;
        }
        if((vard+128)>>8 < c->avctx->mb_threshold)
            mb_type= s->mb_type[mb_x + mb_y*s->mb_stride];
    }

    switch(s->me_method) {
    case ME_ZERO:
    default:
        no_motion_search(s, &mx, &my);
        mx-= mb_x*16;
        my-= mb_y*16;
        dmin = 0;
        break;
#if 0
    case ME_FULL:
        dmin = full_motion_search(s, &mx, &my, range, ref_picture);
        mx-= mb_x*16;
        my-= mb_y*16;
        break;
    case ME_LOG:
        dmin = log_motion_search(s, &mx, &my, range / 2, ref_picture);
        mx-= mb_x*16;
        my-= mb_y*16;
        break;
    case ME_PHODS:
        dmin = phods_motion_search(s, &mx, &my, range / 2, ref_picture);
        mx-= mb_x*16;
        my-= mb_y*16;
        break;
#endif
    case ME_X1:
    case ME_EPZS:
       {
            const int mot_stride = s->b8_stride;
            const int mot_xy = s->block_index[0];

            P_LEFT[0]       = s->current_picture.motion_val[0][mot_xy - 1][0];
            P_LEFT[1]       = s->current_picture.motion_val[0][mot_xy - 1][1];

            if(P_LEFT[0]       > (c->xmax<<shift)) P_LEFT[0]       = (c->xmax<<shift);

            if(!s->first_slice_line) {
                P_TOP[0]      = s->current_picture.motion_val[0][mot_xy - mot_stride    ][0];
                P_TOP[1]      = s->current_picture.motion_val[0][mot_xy - mot_stride    ][1];
                P_TOPRIGHT[0] = s->current_picture.motion_val[0][mot_xy - mot_stride + 2][0];
                P_TOPRIGHT[1] = s->current_picture.motion_val[0][mot_xy - mot_stride + 2][1];
                if(P_TOP[1]      > (c->ymax<<shift)) P_TOP[1]     = (c->ymax<<shift);
                if(P_TOPRIGHT[0] < (c->xmin<<shift)) P_TOPRIGHT[0]= (c->xmin<<shift);
                if(P_TOPRIGHT[1] > (c->ymax<<shift)) P_TOPRIGHT[1]= (c->ymax<<shift);

                P_MEDIAN[0]= mid_pred(P_LEFT[0], P_TOP[0], P_TOPRIGHT[0]);
                P_MEDIAN[1]= mid_pred(P_LEFT[1], P_TOP[1], P_TOPRIGHT[1]);

                if(s->out_format == FMT_H263){
                    c->pred_x = P_MEDIAN[0];
                    c->pred_y = P_MEDIAN[1];
                }else { /* mpeg1 at least */
                    c->pred_x= P_LEFT[0];
                    c->pred_y= P_LEFT[1];
                }
            }else{
                c->pred_x= P_LEFT[0];
                c->pred_y= P_LEFT[1];
            }

        }
        dmin = ff_epzs_motion_search(s, &mx, &my, P, 0, 0, s->p_mv_table, (1<<16)>>shift, 0, 16);

        break;
    }

    /* At this point (mx,my) are full-pell and the relative displacement */
    ppix = c->ref[0][0] + (my * s->linesize) + mx;

    vard = s->dsp.sse[0](NULL, pix, ppix, s->linesize, 16);

    pic->mc_mb_var[s->mb_stride * mb_y + mb_x] = (vard+128)>>8;
//    pic->mb_cmp_score[s->mb_stride * mb_y + mb_x] = dmin;
    c->mc_mb_var_sum_temp += (vard+128)>>8;

#if 0
    printf("varc=%4d avg_var=%4d (sum=%4d) vard=%4d mx=%2d my=%2d\n",
           varc, s->avg_mb_var, sum, vard, mx - xx, my - yy);
#endif
    if(mb_type){
        int p_score= FFMIN(vard, varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*100);
        int i_score= varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*20;
        c->scene_change_score+= ff_sqrt(p_score) - ff_sqrt(i_score);

        if(mb_type == CANDIDATE_MB_TYPE_INTER){
            c->sub_motion_search(s, &mx, &my, dmin, 0, 0, 0, 16);
            set_p_mv_tables(s, mx, my, 1);
        }else{
            mx <<=shift;
            my <<=shift;
        }
        if(mb_type == CANDIDATE_MB_TYPE_INTER4V){
            h263_mv4_search(s, mx, my, shift);

            set_p_mv_tables(s, mx, my, 0);
        }
        if(mb_type == CANDIDATE_MB_TYPE_INTER_I){
            interlaced_search(s, 0, s->p_field_mv_table, s->p_field_select_table, mx, my, 1);
        }
    }else if(c->avctx->mb_decision > FF_MB_DECISION_SIMPLE){
        int p_score= FFMIN(vard, varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*100);
        int i_score= varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*20;
        c->scene_change_score+= ff_sqrt(p_score) - ff_sqrt(i_score);

        if (vard*2 + 200*256 > varc)
            mb_type|= CANDIDATE_MB_TYPE_INTRA;
        if (varc*2 + 200*256 > vard || s->qscale > 24){
//        if (varc*2 + 200*256 + 50*(s->lambda2>>FF_LAMBDA_SHIFT) > vard){
            mb_type|= CANDIDATE_MB_TYPE_INTER;
            c->sub_motion_search(s, &mx, &my, dmin, 0, 0, 0, 16);
            if(s->flags&CODEC_FLAG_MV0)
                if(mx || my)
                    mb_type |= CANDIDATE_MB_TYPE_SKIPPED; //FIXME check difference
        }else{
            mx <<=shift;
            my <<=shift;
        }
        if((s->flags&CODEC_FLAG_4MV)
           && !c->skip && varc>50<<8 && vard>10<<8){
            if(h263_mv4_search(s, mx, my, shift) < INT_MAX)
                mb_type|=CANDIDATE_MB_TYPE_INTER4V;

            set_p_mv_tables(s, mx, my, 0);
        }else
            set_p_mv_tables(s, mx, my, 1);
        if((s->flags&CODEC_FLAG_INTERLACED_ME)
           && !c->skip){ //FIXME varc/d checks
            if(interlaced_search(s, 0, s->p_field_mv_table, s->p_field_select_table, mx, my, 0) < INT_MAX)
                mb_type |= CANDIDATE_MB_TYPE_INTER_I;
        }
    }else{
        int intra_score, i;
        mb_type= CANDIDATE_MB_TYPE_INTER;

        dmin= c->sub_motion_search(s, &mx, &my, dmin, 0, 0, 0, 16);
        if(c->avctx->me_sub_cmp != c->avctx->mb_cmp && !c->skip)
            dmin= ff_get_mb_score(s, mx, my, 0, 0, 0, 16, 1);

        if((s->flags&CODEC_FLAG_4MV)
           && !c->skip && varc>50<<8 && vard>10<<8){
            int dmin4= h263_mv4_search(s, mx, my, shift);
            if(dmin4 < dmin){
                mb_type= CANDIDATE_MB_TYPE_INTER4V;
                dmin=dmin4;
            }
        }
        if((s->flags&CODEC_FLAG_INTERLACED_ME)
           && !c->skip){ //FIXME varc/d checks
            int dmin_i= interlaced_search(s, 0, s->p_field_mv_table, s->p_field_select_table, mx, my, 0);
            if(dmin_i < dmin){
                mb_type = CANDIDATE_MB_TYPE_INTER_I;
                dmin= dmin_i;
            }
        }

//        pic->mb_cmp_score[s->mb_stride * mb_y + mb_x] = dmin;
        set_p_mv_tables(s, mx, my, mb_type!=CANDIDATE_MB_TYPE_INTER4V);

        /* get intra luma score */
        if((c->avctx->mb_cmp&0xFF)==FF_CMP_SSE){
            intra_score= varc - 500;
        }else{
            int mean= (sum+128)>>8;
            mean*= 0x01010101;

            for(i=0; i<16; i++){
                *(uint32_t*)(&c->scratchpad[i*s->linesize+ 0]) = mean;
                *(uint32_t*)(&c->scratchpad[i*s->linesize+ 4]) = mean;
                *(uint32_t*)(&c->scratchpad[i*s->linesize+ 8]) = mean;
                *(uint32_t*)(&c->scratchpad[i*s->linesize+12]) = mean;
            }

            intra_score= s->dsp.mb_cmp[0](s, c->scratchpad, pix, s->linesize, 16);
        }
#if 0 //FIXME
        /* get chroma score */
        if(c->avctx->mb_cmp&FF_CMP_CHROMA){
            for(i=1; i<3; i++){
                uint8_t *dest_c;
                int mean;

                if(s->out_format == FMT_H263){
                    mean= (s->dc_val[i][mb_x + mb_y*s->b8_stride] + 4)>>3; //FIXME not exact but simple ;)
                }else{
                    mean= (s->last_dc[i] + 4)>>3;
                }
                dest_c = s->new_picture.data[i] + (mb_y * 8  * (s->uvlinesize)) + mb_x * 8;

                mean*= 0x01010101;
                for(i=0; i<8; i++){
                    *(uint32_t*)(&c->scratchpad[i*s->uvlinesize+ 0]) = mean;
                    *(uint32_t*)(&c->scratchpad[i*s->uvlinesize+ 4]) = mean;
                }

                intra_score+= s->dsp.mb_cmp[1](s, c->scratchpad, dest_c, s->uvlinesize);
            }
        }
#endif
        intra_score += c->mb_penalty_factor*16;

        if(intra_score < dmin){
            mb_type= CANDIDATE_MB_TYPE_INTRA;
            s->current_picture.mb_type[mb_y*s->mb_stride + mb_x]= CANDIDATE_MB_TYPE_INTRA; //FIXME cleanup
        }else
            s->current_picture.mb_type[mb_y*s->mb_stride + mb_x]= 0;

        {
            int p_score= FFMIN(vard, varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*100);
            int i_score= varc-500+(s->lambda2>>FF_LAMBDA_SHIFT)*20;