Grabcut

Question

在OpenCV中调用抓取之后，我想获取种子点的所有相邻像素，这些像素在掩码中标记为GC_PR_FGD或GC_FGD。我想到要使用类似这样的搜索算法：

vector<Point> pixels_in_component;
vector<Point> neighbours;
Point starting_point;

void GCApplication::reducedPixels(){
    neighbours.push_back(starting_point);

    while(!neighbours.empty()){
        Point p = neighbours.back();
        neighbours.pop_back();
        pixels_in_component.push_back(p);

        double x = p.x;
        double y = p.y;
        if(x > 0)   //Left
        {
            uchar left_val = mask.at<uchar>(y,x-1);
            if(left_val == GC_FGD || left_val == GC_PR_FGD)
                neighbours.push_back(Point(y,x-1));
        }
        if(y>0 && x>0)  //upLeft
        {
            uchar upLeft_val = mask.at<uchar>(y-1,x-1);
            if(upLeft_val == GC_FGD || upLeft_val == GC_PR_FGD)
                neighbours.push_back(Point(y-1,x-1));
        }
        if(y>0) //up
        {
            uchar up_val = mask.at<uchar>(y-1,x);
            if(up_val == GC_FGD || up_val == GC_PR_FGD)
                neighbours.push_back(Point(y-1,x));
        }
        if(y>0 && x<mask.cols-1)    //upright
        {
            uchar upRight_val = mask.at<uchar>(y-1,x+1);
            if(upRight_val == GC_FGD || upRight_val == GC_PR_FGD)
                neighbours.push_back(Point(y-1,x+1));
        }
    }
    CV_Assert( !mask.empty() );
    mask.setTo( GC_BGD );
    for(vector<Point>::iterator it = pixels_in_component.begin(); it != pixels_in_component.end(); it++){
        mask.at<uchar>(it->y,it->x) = GC_FGD;
    }
}

但是问题是它没有检测到所有相邻像素。实际上，它检测到的很少。我正在使用here中的grabCut。