A novel registration method for SAR and SPOT images

In this paper, we propose a novel mutual information (MI) based method to register SAR and SPOT images. The traditional MI can register SAR and SPOT images well. However, its robustness is weakened by the absence of orientation information. In our approach, we first extract orientation information at four directions by Gabor filters, then MI of each corresponding image pair is calculated and the average value of MI is used as an improved measure for MI. Experiments show that our method is more robust than the traditional MI method. Meanwhile our method maintains comparable accuracy to the traditional MI, which is much better than coarse manual registration.