Image Registration Using A Fast Adaptive Algorithm
Rahbar Maghsoodi, Bahman Rezaie · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1987
A three stage algorithm based on central moments and an adaptive classifier is developed to estimate the position of a noisy subimage with unknown angular misalignment within an image. The first stage derives the zero-order moment of pixels inside a circular window recursively and by comparing them to that of the reference image, a number of likely positions are selected. The second stage improves on the first stage by using several concentric circular windows. The third stage compares the higher order moments for the likely position obtained in the second stage. An adaptive classifier is used in parallel with the third stage in order to decide whether the computationally intensive high order moments should be calculated for a given neighborhood of the likely positions. This classifier ex-ploits the fact that the measure of similarity of the neighboring pixels does not vary substantially. Implementation of the algorithm on real images has indicated that, in many cases, the exact location of the rotated object within a noisy image can be determined.