What type of images are they? If you are working with face images, we have actually implemented a tool (EyepadAlign in mlxtend 6) for preprocessing face images to align them based on eyes, and nose. This module also allows you to align the position of face images in one dataset to match with another dataset, which is useful for cross-dataset evaluation. You can see examples in the docs: https://github.com/rasbt/mlxtend/blob/master/docs/sources/user_guide/image/eyepad_align.ipynb 47