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### Issue with meanStdDev() result and Mat channels

meanStdDev() is not giving the correct calculation of mean and standard. I want it to give mean/stdev for each corresponding column. The code follows,

Mat_<int> C = (Mat_<int>(2,6) << 1, 0, 3, 1, 0, 5, 6, 2, 0, 4, 0, 9), E=Mat::zeros(9, 9, CV_8UC1);
Mat mn, stdev;
meanStdDev(C.reshape(C.cols),mn,stdev);
std::cout << C.reshape(C.cols) << endl<< mn << std::endl;


It gives the following results,

[1, 0, 3, 1, 0, 5;
6, 2, 0, 4, 0, 9]

[2.5;
1;
0;
0;
0;
0]


You can see that the calculated mean value is corrent only for the first 2 positions