Rotation Invariance in Images

Rotation is one of the most basic transformations that can relate two images. Two determine if two images are rotated versions of each other, one can either exhaustively rotate them in order to find out if the two match up at some angle, or alternatively extract features from the images that can then be compared to make the same decision. In this paper, we will propose a novel method for extracting the components of an image that are invariant to rotation based on the Fourier transform. We will compare the performance of the algorithm to the exhaustive search method and show that this is a much faster technique, that is also accurate in matching rotated images.