Placing Object Detection Video On Orginal Video

I have been working on a project where I am detecting an object. Right now I have a video of type struct that shows only my object in white and everything else black. My question is: is it possible for me to take my original video, which is in color, and incorporate just the white object in my other video? So basically I want to overlap my original video with my new video but just incorporate my object detected which is white. Please help!