

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);