error_resilience.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.7平台上编译为嵌入式图形界面操作系统。

static void guess_mv(MpegEncContext *s){
    UINT8 fixed[s->mb_num];
#define MV_FROZEN    3
#define MV_CHANGED   2
#define MV_UNCHANGED 1
    const int mb_width = s->mb_width;
    const int mb_height= s->mb_height;
    int i, depth, num_avail;
   
    num_avail=0;
    for(i=0; i<s->mb_num; i++){
        int f=0;
        int error= s->error_status_table[i];

        if(s->mb_type[i]&MB_TYPE_INTRA) f=MV_FROZEN; //intra //FIXME check
        if(!(error&MV_ERROR)) f=MV_FROZEN;           //inter with undamaged MV
        
        fixed[i]= f;
        if(f==MV_FROZEN)
            num_avail++;
    }
    
    if((!(s->avctx->error_concealment&FF_EC_GUESS_MVS)) || num_avail <= mb_width/2){
        int mb_x, mb_y;
        i= -1;
        for(mb_y=0; mb_y<s->mb_height; mb_y++){
            for(mb_x=0; mb_x<s->mb_width; mb_x++){
                i++;
                
                if(s->mb_type[i]&MB_TYPE_INTRA) continue;
                if(!(s->error_status_table[i]&MV_ERROR)) continue;

                s->mv_dir = MV_DIR_FORWARD;
                s->mb_intra=0;
                s->mv_type = MV_TYPE_16X16;
                s->mb_skiped=0;

		s->dsp.clear_blocks(s->block[0]);

                s->mb_x= mb_x;
                s->mb_y= mb_y;
                s->mv[0][0][0]= 0;
                s->mv[0][0][1]= 0;
                MPV_decode_mb(s, s->block);
            }
        }
        return;
    }
    
    for(depth=0;; depth++){
        int changed, pass, none_left;

        none_left=1;
        changed=1;
        for(pass=0; (changed || pass<2) && pass<10; pass++){
            int i,mb_x, mb_y;
int score_sum=0;
 
            changed=0;
            i= -1;
            for(mb_y=0; mb_y<s->mb_height; mb_y++){
                for(mb_x=0; mb_x<s->mb_width; mb_x++){
                    int mv_predictor[8][2]={{0}};
                    int pred_count=0;
                    int j;
                    int best_score=256*256*256*64;
                    int best_pred=0;
                    const int mot_stride= mb_width*2+2;
                    const int mot_index= mb_x*2 + 1 + (mb_y*2+1)*mot_stride;
                    int prev_x= s->motion_val[mot_index][0];
                    int prev_y= s->motion_val[mot_index][1];

                    i++;
                    if((mb_x^mb_y^pass)&1) continue;
                    
                    if(fixed[i]==MV_FROZEN) continue;
                    
                    j=0;
                    if(mb_x>0           && fixed[i-1       ]==MV_FROZEN) j=1;
                    if(mb_x+1<mb_width  && fixed[i+1       ]==MV_FROZEN) j=1;
                    if(mb_y>0           && fixed[i-mb_width]==MV_FROZEN) j=1;
                    if(mb_y+1<mb_height && fixed[i+mb_width]==MV_FROZEN) j=1;
                    if(j==0) continue;

                    j=0;
                    if(mb_x>0           && fixed[i-1       ]==MV_CHANGED) j=1;
                    if(mb_x+1<mb_width  && fixed[i+1       ]==MV_CHANGED) j=1;
                    if(mb_y>0           && fixed[i-mb_width]==MV_CHANGED) j=1;
                    if(mb_y+1<mb_height && fixed[i+mb_width]==MV_CHANGED) j=1;
                    if(j==0 && pass>1) continue;
                    
                    none_left=0;
                    
                    if(mb_x>0 && fixed[i-1]){
                        mv_predictor[pred_count][0]= s->motion_val[mot_index - 2][0];
                        mv_predictor[pred_count][1]= s->motion_val[mot_index - 2][1];
                        pred_count++;
                    }
                    if(mb_x+1<mb_width && fixed[i+1]){
                        mv_predictor[pred_count][0]= s->motion_val[mot_index + 2][0];
                        mv_predictor[pred_count][1]= s->motion_val[mot_index + 2][1];
                        pred_count++;
                    }
                    if(mb_y>0 && fixed[i-mb_width]){
                        mv_predictor[pred_count][0]= s->motion_val[mot_index - mot_stride*2][0];
                        mv_predictor[pred_count][1]= s->motion_val[mot_index - mot_stride*2][1];
                        pred_count++;
                    }
                    if(mb_y+1<mb_height && fixed[i+mb_width]){
                        mv_predictor[pred_count][0]= s->motion_val[mot_index + mot_stride*2][0];
                        mv_predictor[pred_count][1]= s->motion_val[mot_index + mot_stride*2][1];
                        pred_count++;
                    }
                    if(pred_count==0) continue;
                    
                    if(pred_count>1){
                        int sum_x=0, sum_y=0;
                        int max_x, max_y, min_x, min_y;

                        for(j=0; j<pred_count; j++){
                            sum_x+= mv_predictor[j][0];
                            sum_y+= mv_predictor[j][1];
                        }
                    
                        /* mean */
                        mv_predictor[pred_count][0] = sum_x/j;
                        mv_predictor[pred_count][1] = sum_y/j;
                    
                        /* median */
                        if(pred_count>=3){
                            min_y= min_x= 99999;
                            max_y= max_x=-99999;
                        }else{
                            min_x=min_y=max_x=max_y=0;
                        }
                        for(j=0; j<pred_count; j++){
                            max_x= FFMAX(max_x, mv_predictor[j][0]);
                            max_y= FFMAX(max_y, mv_predictor[j][1]);
                            min_x= FFMIN(min_x, mv_predictor[j][0]);
                            min_y= FFMIN(min_y, mv_predictor[j][1]);
                        }
                        mv_predictor[pred_count+1][0] = sum_x - max_x - min_x;
                        mv_predictor[pred_count+1][1] = sum_y - max_y - min_y;
                        
                        if(pred_count==4){
                            mv_predictor[pred_count+1][0] /= 2;
                            mv_predictor[pred_count+1][1] /= 2;
                        }
                        pred_count+=2;
                    }
                    
                    /* zero MV */
                    pred_count++;

                    /* last MV */
                    mv_predictor[pred_count][0]= s->motion_val[mot_index][0];
                    mv_predictor[pred_count][1]= s->motion_val[mot_index][1];
                    pred_count++;                    
                    
                    s->mv_dir = MV_DIR_FORWARD;
                    s->mb_intra=0;
                    s->mv_type = MV_TYPE_16X16;
                    s->mb_skiped=0;

		    s->dsp.clear_blocks(s->block[0]);

                    s->mb_x= mb_x;
                    s->mb_y= mb_y;
                    for(j=0; j<pred_count; j++){
                        int score=0;
                        UINT8 *src= s->current_picture[0] + mb_x*16 + mb_y*16*s->linesize;

                        s->motion_val[mot_index][0]= s->mv[0][0][0]= mv_predictor[j][0];
                        s->motion_val[mot_index][1]= s->mv[0][0][1]= mv_predictor[j][1];
                        MPV_decode_mb(s, s->block);
                        
                        if(mb_x>0 && fixed[i-1]){
                            int k;
                            for(k=0; k<16; k++)
                                score += ABS(src[k*s->linesize-1 ]-src[k*s->linesize   ]);
                        }
                        if(mb_x+1<mb_width && fixed[i+1]){
                            int k;
                            for(k=0; k<16; k++)
                                score += ABS(src[k*s->linesize+15]-src[k*s->linesize+16]);
                        }
                        if(mb_y>0 && fixed[i-mb_width]){
                            int k;
                            for(k=0; k<16; k++)
                                score += ABS(src[k-s->linesize   ]-src[k               ]);
                        }
                        if(mb_y+1<mb_height && fixed[i+mb_width]){
                            int k;
                            for(k=0; k<16; k++)
                                score += ABS(src[k+s->linesize*15]-src[k+s->linesize*16]);
                        }
                        
                        if(score <= best_score){ // <= will favor the last MV
                            best_score= score;
                            best_pred= j;
                        }
                    }
score_sum+= best_score;
//FIXME no need to set s->motion_val[mot_index][0] explicit
                    s->motion_val[mot_index][0]= s->mv[0][0][0]= mv_predictor[best_pred][0];
                    s->motion_val[mot_index][1]= s->mv[0][0][1]= mv_predictor[best_pred][1];

                    MPV_decode_mb(s, s->block);

                    
                    if(s->mv[0][0][0] != prev_x || s->mv[0][0][1] != prev_y){
                        fixed[i]=MV_CHANGED;
                        changed++;
                    }else
                        fixed[i]=MV_UNCHANGED;
                }
            }

//            printf(".%d/%d", changed, score_sum); fflush(stdout);
        }
        
        if(none_left) 
            return;
            
        for(i=0; i<s->mb_num; i++){
            if(fixed[i])
                fixed[i]=MV_FROZEN;
        }
//        printf(":"); fflush(stdout);
    }
}
    
static int is_intra_more_likely(MpegEncContext *s){
    int is_intra_likely, i, j, undamaged_count, skip_amount, mb_x, mb_y;

    undamaged_count=0;
    for(i=0; i<s->mb_num; i++){
        int error= s->error_status_table[i];
        if(!((error&DC_ERROR) && (error&MV_ERROR)))
            undamaged_count++;
    }
    
    if(undamaged_count < 5) return 0; //allmost all MBs damaged -> use temporal prediction
    
    skip_amount= FFMAX(undamaged_count/50, 1); //check only upto 50 MBs 
    is_intra_likely=0;

    j=0;
    i=-1;
    for(mb_y= 0; mb_y<s->mb_height-1; mb_y++){
        for(mb_x= 0; mb_x<s->mb_width; mb_x++){
            int error;

            i++;
            error= s->error_status_table[i];
            if((error&DC_ERROR) && (error&MV_ERROR))
                continue; //skip damaged
        
            j++;    
            if((j%skip_amount) != 0) continue; //skip a few to speed things up
    
            if(s->pict_type==I_TYPE){
                UINT8 *mb_ptr     = s->current_picture[0] + mb_x*16 + mb_y*16*s->linesize;
                UINT8 *last_mb_ptr= s->last_picture   [0] + mb_x*16 + mb_y*16*s->linesize;
    
		is_intra_likely += s->dsp.pix_abs16x16(last_mb_ptr, mb_ptr                    , s->linesize);
                is_intra_likely -= s->dsp.pix_abs16x16(last_mb_ptr, last_mb_ptr+s->linesize*16, s->linesize);
            }else{
                if(s->mbintra_table[i]) //HACK (this is allways inited but we should use mb_type[])
                   is_intra_likely++;
                else
                   is_intra_likely--;
            }
        }
    }
//printf("is_intra_likely: %d type:%d\n", is_intra_likely, s->pict_type);
    return is_intra_likely > 0;    
}

void ff_error_resilience(MpegEncContext *s){
    int i, mb_x, mb_y, error, error_type;
    int distance;
    int threshold_part[4]= {100,100,100};
    int threshold= 50;
    int is_intra_likely;
    
#if 1
    /* handle overlapping slices */
    for(error_type=1; error_type<=3; error_type++){
        int end_ok=0;

        for(i=s->mb_num-1; i>=0; i--){
            int error= s->error_status_table[i];
        
            if(error&(1<<error_type))
                end_ok=1;