Copy an cv::Mat inside a ROI of another one

Question

I need to copy a cv::Mat image (source) to an ROI of another (Destination) cv::Mat image.

I found this reference, but it seems that it does

Answer 1

In addition or correction to above answers, if you want to copy a smaller region of open Mat to another Mat, you should do:

src(Rect(left,top,width, height)).copyTo(dst);