Position of a Roi in a mat

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If you have created the ROI using cv::Rect() or cv::Range(), you can use locateROI, see http://docs.opencv.org/modules/core/d... . If you want to find a subimage not steming from the same Matrix (i.e. not created by cv::Rect() or cv::Range()) in a Matrix, then you would need to use matchTemplate(http://docs.opencv.org/modules/imgpro...).