#include<iostream>
#include<opencv2/opencv.hpp>
using namespace std;
using namespace cv;
int main(){
Mat image(600,800,CV_8UC1);
Mat image2(600,800,CV_8UC3);
for (int i = 0; i < image.rows; ++i)
{
/*uchar * p = image.ptr<uchar>(i);*/
for (int j = 0; j < image.cols;++j){
/*p[j] = (i + j) % 255;*/
image.at<uchar>(i,j) = 0;
}
}
for (int i = 0; i < image2.rows; ++i){
for (int j = 0; j < image2.cols; ++j){
image2.at<Vec3b>(i, j)[0] = 255;
image2.at<Vec3b>(i, j)[1] = 255;
image2.at<Vec3b>(i, j)[2] = 255;
}
}
imshow("image",image);
imshow("image2", image2);
waitKey(0);
}
注意:for循环里面,必须先是rows,然后cols,否则会出现错误,而在for里面的,外层循环和内层循环,rows和cols谁在里在外,则无所谓。
若image.at<uchar>(cols,rows),则报错:
<img src="https://img-blog.youkuaiyun.com/20150708185201436?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
<img src="https://img-blog.youkuaiyun.com/20150708185240670?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
</pre><pre name="code" class="cpp">
但是,遍历图像的时候,不推荐使用at()函数,因为使用这个函数的效率不高,虽然代码可读性高。