I have a template image and want to match it with a set of images. Since the template could be in a rotated position or scaled in the image I want to use ORB.

I have extracted the ORB descriptor for the template image and for each of the images to be matched.

Question-how should I assess the degree of match between the template's ORB descriptor and that for the image?
Can I use len()  ndarray returned by match_descriptors since I'm specifying the same # keypoints for both the templete and the images?