I am working on a project to fuse two images, RGB + Infrared (1 Channel). I noticed the images from RGB source has a slightly wider angle than IR source. Both image souces have different resolution as well. RGB 1800x1600pixels, whereas IR source 640x512 pixels. I have tried to manually crop and then feed new image into fusion algorithm, but I would not consider my croping to be as good. Is there an optimal way to align two images, so that they can be fed into an algorithm?