Opencv---画像コントラストと輝度調整

#include 
#include 

using namespace cv;

int main(int argc, char** argv) {
	Mat src, dst;
	src = imread("C:/usr/opencv-test/Testpictures/sight.jpg");
	if (src.empty())
	{
		printf("load image failed!
");
		return -1;
	}
	namedWindow("input image", WINDOW_AUTOSIZE);
	imshow("input image", src);

	int height = src.rows;
	int width = src.cols;
	int nc = src.channels();
	dst = Mat::zeros(src.size(), src.type()); //   dst  src   、       

	float alpha = 1.2;
	float beta = 30.0;
	for (int row = 0; row < height; row++)
	{
		for (int col = 0; col < width; col++)
		{
			//   
			if (nc == 1)
			{
				float v = src.at(row, col); 
				dst.at(row, col) = saturate_cast(v*alpha + beta);
			}
			//   
			else if (nc == 3)
			{
				float b = src.at(row, col)[0];
				float g = src.at(row, col)[1];
				float r = src.at(row, col)[2];
				dst.at(row, col)[0] = saturate_cast(b*alpha + beta);
				dst.at(row, col)[1] = saturate_cast(g*alpha + beta);
				dst.at(row, col)[2] = saturate_cast(r*alpha + beta);
			}
		}
	}

	imshow("contrast and brightness change", dst);


	waitKey(0);
	return 0;
}