도형들의 중심값을 구해서 그 도형들 사이에 선을 이을라하는데 중심선을 구하는게 이게아닌가여

#include <opencv2/opencv.hpp> 
#include <iostream>
using namespace cv;
using namespace std;

string title = "트랙바 이벤트";
Mat image, dst;

void onChange(int Threshold, void* userdata)
{
    Point pt;
    for (pt.y = 0; pt.y < image.rows; pt.y++)
        for (pt.x = 0; pt.x < image.cols; pt.x++)
        {
            if (image.at<uchar>(pt.y, pt.x) < Threshold)
                dst.at<uchar>(pt.y, pt.x) = 0;
            else
                dst.at<uchar>(pt.y, pt.x) = 255;
        }
    imshow(title, dst);
}

int main()
{
    int pos = 128;
    image = imread("hwfig2-2.jpg", IMREAD_GRAYSCALE);

    Mat img2(image.rows, image.cols, CV_8UC3);

    int acount = 0, 
        bcount = 0, 
        ccount = 0, 
        dcount = 0,
        count = 0;

    double axsum = 0, aysum = 0, 
           bxsum = 0, bysum = 0, 
           cxsum = 0, cysum = 0, 
           dxsum = 0, dysum = 0;

    cv::Point_<double> z_1_1, z_1_2,
        z_2_1, z_2_2,
        z_3_1, z_3_2,
        z_4_1, z_4_2;

    Point pt;
    for (pt.y = 0; pt.y < image.rows; pt.y++)
        for (pt.x = 0; pt.x < image.cols; pt.x++)
        {            
            if (image.at<uchar>(pt.y, pt.x) < 150) {
                img2.at<Vec3b>(pt.y, pt.x) = Vec3b(0, 255, 255);
                axsum += pt.x;
                aysum += pt.y; 
                acount++;
            }
            else if (image.at<uchar>(pt.y, pt.x) > 150 && image.at<uchar>(pt.y, pt.x) < 180) {
                img2.at<Vec3b>(pt.y, pt.x) = Vec3b(0, 255, 0);
                bxsum += pt.x;
                bysum += pt.y;
                bcount++;
            }
            else if (image.at<uchar>(pt.y, pt.x) > 180 && image.at<uchar>(pt.y, pt.x) < 230) {
                img2.at<Vec3b>(pt.y, pt.x) = Vec3b(0, 0, 255);
                cxsum += pt.x;
                cysum += pt.y;
                ccount++;
            }
            else if (image.at<uchar>(pt.y, pt.x) > 230 && image.at<uchar>(pt.y, pt.x) < 250) {
                img2.at<Vec3b>(pt.y, pt.x) = Vec3b(255, 0, 0);
                dxsum += pt.x;
                dysum += pt.y;
                dcount++;
            }
            else {
                img2.at<Vec3b>(pt.y, pt.x) = Vec3b(255, 255, 255);
            }
        }

    z_1_1 = (Point)axsum / acount,(Point)aysum / acount;
    z_2_1 = (Point)bxsum / bcount,(Point)bysum / bcount;
    z_3_1 = (Point)cxsum / ccount,(Point)cysum / ccount;
    z_4_1 = (Point)dxsum / dcount,(Point)dysum / dcount;

    line(img2, z_1_1, z_2_1, Scalar(0, 0, 0), LINE_4, 1);
    line(img2, z_2_1, z_3_1, Scalar(0, 0, 0), LINE_4, 1);
    line(img2, z_3_1, z_4_1, Scalar(0, 0, 0), LINE_4, 1);
    line(img2, z_4_1, z_1_1, Scalar(0, 0, 0), LINE_4, 1);

    imshow("img1", image);
    imshow("img2", img2);

    waitKey(0);
    return 0;
}