Effective Estimation of Image Rotation Angle Using Spectral Method

In this letter, we propose a blind and effective method to estimate the image rotation angle. It operates by exploiting the hidden periodicities in the rotated image using the 2-D spectrum of its second order statistics. The expected positions of rotation-related peaks as well as their trajectory paths in the 2-D spectrum are first derived. Based on the peaks found around those paths, the rotation angle is then estimated using a much simpler formula than those of the state-of-the-art 2-D method. Through both theoretical analyses and experimental results on a large set of natural images, the proposed scheme is demonstrated to give more accurate estimate than previous methods.