A Modified HOPC Algorithm for SAR Image Registration

Synthetic aperture radar (SAR) image registration using the histogram of orientated phase congruency (HOPC) is a challenging task due to HOPC lacks rotation and scale invariance. In this paper, a modified HOPC algorithm is proposed to address the aforementioned problems. Firstly, the brief review on HOPC and its limitations are introduced. Secondly, the scale invariant feature transform (SIFT) algorithm is used to rotate image for handle the rotation invariance. Subsequently, multi-scale phase congruency features are extracted in phase congruency scale space, and original HOPC is used to match features. Finally, we use random sample consensus (RANSAC) to filter all the matches to obtain correct matches. In this paper, TerraSAR-X and Sentinel-1A data are used as experimental data. We utilize different assessment paraments to evaluate the performance of the modified HOPC algorithm. The experimental results demonstrate the proposed algorithm outperforms the state-of-art algorithms in terms of registration accuracy.