Add the contents of 2 Mats to another Mat opencv c++

c++, mat, opencv

Solution

It depends on what you want to add. For example, you have two 3x3 Mat:

cv::Mat matA(3, 3, CV_8UC1, cv::Scalar(20));
cv::Mat matB(3, 3, CV_8UC1, cv::Scalar(80));

You can add `matA` and `matB` to a new 3x3 Mat with value 100 using matrix operation:

auto matC = matA + matB;

Or using array operation cv::add that does the same job:

cv::Mat matD;
cv::add(matA, matB, matD);

Or even mixing two images using cv::addWeighted:

cv::Mat matE;
cv::addWeighted(matA, 1.0, matB, 1.0, 0.0, matE);

Sometimes you need to merge two Mat, for example create a 3x6 Mat using cv::Mat::push_back:

cv::Mat matF;
matF.push_back(matA);
matF.push_back(matB);

Even merge into a two-channel 3x3 Mat using cv::merge:

auto channels = std::vector<cv::Mat>{matA, matB};
cv::Mat matG;
cv::merge(channels, matG);

Think about what you want to add and choose a proper function.

Problem

I just want to add the contents of 2 different `Mat`s to 1 other `Mat`. I tried: ``` Mat1.copyTo(newMat); Mat2.copyTo(newMat); ``` But that just seemed to overwrite the previous contents of the `Mat`. This may be a simple question, but I'm lost.

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