In open cv, how can i convert gray scale image back in to RGB image(color)

Question

In open cv to remove background, using current frame and former frame, i applied absdiff function and created a difference image in gray scale. However, i would like to covert the gray scale image back in to RGB with actual color of the image, but i have no idea how to operate this back in. I'm using C++. Could any one knowledgeable of open cv help me?

Answer 1

You cannot covert the gray scale image back into RGB with actual color of the image again as coverting RGB to gray scale is a data-losing process.

Instead, as @MatsPetersson suggested, you can take the use of the grayscale image to create a mask, eg by further applying a thresholding process . Then you can easily get the ROI color image by:

cv::Mat dst;
src.copyTo(dst, mask);