c++ - Mat::ones 在 OpenCV 中不起作用

Question

int main () {    

    Mat A = Mat::ones(100, 100, CV_8U)*3;
    cout << A.at<int>(0,0) << endl;

    return 0;
}

输出是一个非常大的数::50529027

谁能帮帮我？？ C++代码

Answer 1

you're casting to the wrong type in A.at<int>() // should be uchar instead of int

so, A.at<int>(0,0) sees 0x03030303, which is, in fact 50529027.

Mat A = Mat::ones(100, 100, CV_8U)*3;
cout << int(A.at<uchar>(0,0)) << endl;

(围绕 A.at() 的转换只是为了用 cout 而不是 char 显示数字)