An Improved Two-Stage Image Registration Algorithm for Super-Resolution

This paper presents an improved two-stage image registration algorithm for super-resolution. The algorithm is based on the rotation-translation (RT) model and the coarse-to-fine strategy. It first uses the phase correlation algorithm to estimate large-scale displacements with pixel-level accuracy after image motion compensation, and then uses the Keren algorithm to obtain high-accuracy sub-pixel estimation. Moreover, from the non-commutative property between rotation and translation in the RT model, synthesis formulae are derived and used to combine the two results together, which could further improve the accuracy without extra computational costs. The algorithm can achieve high-accuracy sub-pixel registration for large-scale displacements, which also has the advantage of good computational efficiency. To illustrate the effectiveness of the algorithm, both simulations and practical super-resolution reconstruction experiments are performed. (C) 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.