Mat color = imread("flover.jpeg");
    Mat lut = Mat::zeros(256, 1, CV_8UC3);
    for (int i = 0; i < 256; ++i) {
        lut.at<Vec3b>(i, 0) = color.at<Vec3b>(30, i);
    }
    imshow("color", color);
    Mat dist;
    LUT(color, lut, dist);
    imshow("dist", dist);
    applyColorMap(color, dist, COLORMAP_SUMMER);

    imshow("dist2", dist);
    waitKey(0);