OpenCV生成原始LUT图

void LutSrcMap(Mat &Src) {

	
	Src.create(256, 256, CV_8UC3);
	for (int i = 0; i < Src.rows; i++) {

		uchar *src = Src.ptr(i);
		for (int j = 0; j < Src.cols; j++) {

			int v =(int)(255*sqrt((i*i + j * j)*1.0 / (2 * 256 * 256)));
			src[j * 3 ] =v;
			src[j * 3 + 1] =v;
			src[j * 3 + 2] =v;
		}
	}

}

结果图

可以用此来提取PhotoShop 正片叠底的LUT效果