连通分量算法输出

Question

目前，我正在实现一种识别图像中连接组件的算法。在执行自适应阈值处理之后，我又创建了另一个名为sub的Mat变量，其中我正在更新它的值，因此包含它们的值允许我使用更新的'newObject‘变量来识别哪些像素连接到哪个像素。

我的预期输出，当我完成这是一个相对连接的图片与不同的强度，它可以看到哪些部分连接到哪。但是，我的问题是，作为子变量的输出只显示一个黑色图像。

我已经通过放置print语句来检查当前值，从而检查了这些值是否实际发生了更改。我还在if语句中放置了不同的print语句，并了解到它们确实进入了我更改子变量中像素值的条件。

我的问题是，为什么当我对子变量执行imshow函数时，输出图像是黑色的。对不起，如果我在某个地方犯了错，我在这方面还是比较新的。

for(int i = 0; i < detected_edges.rows; i++){
        for(int j = 0; j < detected_edges.cols; j++){
            if(detected_edges.at<uchar>(i,j) > 0){
                Point current = (i,j);
                if(i-1 < 0 && j-1 < 0){
                    newObject = newObject + 15;     //no values
                    sub.at<uchar>(current) = newObject;
                    printf("This is the value at this point: %u", sub.at<uchar>(current));
                }else if(i-1 >= 0 && j-1 < 0){
                    Point up = (i-1,j);
                    if(sub.at<uchar>(up) != 0){
                        sub.at<uchar>(current) = sub.at<uchar>(up);                 //only up has value
                    }else{
                        newObject = newObject + 15;                                             //no values
                        sub.at<uchar>(current) = newObject;
                    }
                }else if(i-1 < 0 && j-1 >= 0){
                    Point left = (i,j-1);
                    if(sub.at<uchar>(left) != 0){
                        sub.at<uchar>(current) = sub.at<uchar>(left);               //only left has value
                    }else{
                        newObject = newObject + 15;                                 //no values
                        sub.at<uchar>(current) = newObject;
                    }
                }else{
                    Point up = (i-1,j);
                    Point left = (i,j-1);
                    if(sub.at<uchar>(up) == 0 && sub.at<uchar>(left) == 0){

                        newObject = newObject + 15;                                             //no values
                        sub.at<uchar>(current) = newObject;
                    }else if(sub.at<uchar>(up) == sub.at<uchar>(left)){             //same value
                        sub.at<uchar>(current) = sub.at<uchar>(up);
                    }else if(sub.at<uchar>(up) != sub.at<uchar>(left) && (sub.at<uchar>(up) != 0 && sub.at<uchar>(left) != 0)){
                        sub.at<uchar>(current) = sub.at<uchar>(up);                 //different values follow upper's value
                    }else if((sub.at<uchar>(up) != 0 && sub.at<uchar>(left) == 0)){
                        sub.at<uchar>(current) = sub.at<uchar>(up);                 //only up has value
                    }else if(sub.at<uchar>(up) == 0 && sub.at<uchar>(left) != 0 ){
                        sub.at<uchar>(current) = sub.at<uchar>(left);               //only left has value
                    }
                }
            }
        }
    }

更新:我注意到只有'sub‘Mat变量中的第一行由于某种原因而更改值，即使循环会上升到图像的最后一行。

Answer 1

之所以图像是黑色的，是因为我通过创建更多的对象来查看灰度图像(0-255)的值范围。我使用2D数组执行了不同的实现，并对算法进行了实现。