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Setting ROI with mouse from a rectangle on a video
I am developing a simple application in opencv which will show a one third of video stream as grayscale, that one-third region is based on user's mouth detection. If the mouth is at extreme right then the right one-third of screen converts to grayscale. I am unable to find an approach to convert specific part to grayscale based on detection. Please can somebody identify the correct way of doing this.
I am using OpenCV version 2.3 in ubuntu