Stable feature point extraction for accurate multi-temporal SAR image registration

Feature extraction is an important issue for image interpretation, many valuable feature extraction methods have been proposed to address synthetic aperture radar (SAR) image registration. However, the current methods care little about changes over multi-temporal SAR images, which result in unstable output features. The unstable property is a latent factor to affect the accuracy of SAR image registration. To overcome this problem, we propose a new method to detect stable features by intersecting Coherent Scatters (CS) and SAR-FAST corners. Thus the stable features are not only corners but also located at the time-invariant area. Then, the stable features are described by SIFT descriptors and the coarse registration is achieved by matching these stable points. Finally, the Powell algorithm is used to search the optimal Mutual Information location for precise registration. Experimental results demonstrate the effectiveness of the proposed method.