将图片的像素翻转

转载：https://blog.csdn.net/qq_35661436/article/details/79176462

//written by Mr.zs
//编程环境：VS2017 x64
/*
功能:将图片的像素翻转
zhuy
*/
#include <opencv2\opencv.hpp>
#include <iostream>
using namespace cv;
int main()
{
	Mat src = imread("v.jpg");
	if (!src.data) {
		std::cout << "not find image!!! " << std::endl;
		return -1;
	}
	//cvtColor(src, src, CV_BGR2GRAY);
	Mat dst = Mat::zeros(src.size(), src.type());
	int dst_rows = src.rows;
	int dst_cols = src.cols;
	for (int i = 0; i < dst_rows; i++) {
		for (int j = 0; j < dst_cols; j++) {
			if (src.channels() == 1) {//灰度图像
				int v = src.at<uchar>(i, j);
				dst.at<uchar>(i, j) = saturate_cast<uchar>(255 - v);
			}
			else if (src.channels() == 3) {//rgb图像
				int b = src.at<Vec3b>(i, j)[0];
				int g = src.at<Vec3b>(i, j)[1];
				int r = src.at<Vec3b>(i, j)[2];
 
				dst.at<Vec3b>(i, j)[0] = saturate_cast<uchar>(r);
				dst.at<Vec3b>(i, j)[1] = saturate_cast<uchar>(g);
				dst.at<Vec3b>(i, j)[2] = saturate_cast<uchar>(b);
			}
		}
	}
	imshow("src", src);
	imshow("dst", dst);
	waitKey();
	return 0;
}