OpenCV.2.Computer.Vision.Application.Programming.Cookbook--Accessing pixel values

#include<opencv2\opencv.hpp>void salt(cv::Mat &image, int n){for (int k=0; k<n; k++) {// rand() is the MFC random number generatorint i= rand()%image.cols;int j= rand()%image.rows;if (image.channels() == 1) { // gray-level imageimage.at<uchar>(j,i)= 255;} else if (image.channels() == 3){ // color imageimage.at<cv::Vec3b>(j,i)[0]= 255;image.at<cv::Vec3b>(j,i)[1]= 255;image.at<cv::Vec3b>(j,i)[2]= 255;}}}int main(int argc,char* argv[]){cv::Mat pImg;pImg=cv::imread("lena.jpg");cv::namedWindow("Image");cv::imshow("Image",pImg);salt(pImg,300);cv::namedWindow("pImg");cv::imshow("pImg",pImg);cv::waitKey(0);cv::destroyWindow("Image");return 0;}