opencv像素点获取

单通道img像素点读取 ：

img.at<Vec3b>(i,j)

多通道图像像素点读取：

Vec3b S=img.at<Vec3b>(i,j); cout<<S.val[0]<<"  "<<S.val[1]<<"  "<<s.val[2]<<endl;或者k=img.at<Vec3b>(i,j)[0] 

实例

#include<opencv2/core/core.hpp>#include<opencv2/highgui/highgui.hpp>using namespace cv;using namespace std;int main(){Mat img=imread("lena.jpg"); //载入图像到Mat  namedWindow("lena"); //创建窗口   imshow("lena",img);//显示窗口   for(int i=0;i<img.rows;i++){for(int i=0;j<img.cols;j++){img.at<Vec3b>(i,j)[0]=0;}}imwrite("lena_r0.jpg",img);  waitKey();  return 0;  }