Extract parts of an image based on a raster mask?

Hi, First of all I would like to say hi to the community because I'm a newcomer. I have been reading about openCV for some days and I would like to use it in my jigsaw game (Android and IOS). What I need is to extract parts of an image based on pieces defined in another image (raster mask). The mask could be something like this:  This image is defining just the outlines of each piece at each position. And I would like to cut the image based o this outlines. Can OpenCV help with this? I'm a bit lost right now. My intuition is saying openCV can do this but don't know how to achieve it. Any help will be greatly appreciated. Cheers.