#include <opencv2/opencv.hpp>
#include<opencv2/imgproc/imgproc.hpp>
#include<iostream>


using namespace std;
using namespace cv;


int main()
{
	//分离方法一，超麻烦，是官网的教程
	Mat img;
	img = imread("timg.jpg");
	Mat R(img.rows, img.cols, CV_8UC3, Scalar(0, 0, 0));
	Mat B(img.rows, img.cols, CV_8UC3, Scalar(0, 0, 0));
	Mat G(img.rows, img.cols, CV_8UC3, Scalar(0, 0, 0));

	Mat out[] = { B };
	int from_to[] = { 0,0 };
	mixChannels(&img, 1, out, 1, from_to, 1);
	imshow("1 channel", B);
	waitKey();

	out[0] = G;
	from_to[0] = 1;
	from_to[1] = 1;
	mixChannels(&img, 1, out, 1, from_to, 1);
	imshow("1 channel", G);
	waitKey();

	out[0] = R;
	from_to[0] = 2;
	from_to[1] = 2;
	mixChannels(&img, 1, out, 1, from_to, 1);
	imshow("1 channel", R);
	waitKey();

	//方法2，CSDN上的
	Mat imageROI,Combine;
	vector<Mat> channels;

	// 把一个3通道图像转换成3个单通道图像
	split(img, channels);//分离色彩通道
	imageROI = channels.at(0);

	imshow("c0", imageROI);
	waitKey();

	merge(channels, Combine);

	imshow("Combine", Combine);

	waitKey();
	return 0;
}