A New Approach for SAR Images Matching Based on Optimal Gradient Filter and Multi-Window Method
Ghannadi, Mohammad amin; Mohamad, Saadatseresht; akram, eftekhari; Mahdi, Motagh
University of Tehran, IRAN, ISLAMIC REPUBLIC OF
Digital elevation models (DEM) can be generate by interferometric SAR and Radargrammetry techniques from SAR images. The efficient algorithm for matching of SAR images is one of the key points for improving both accuracy and efficiency. In this paper a new Feature Base image matching technique is defined based on optimal gradient filter and multi-window approach. In this algorithm, a SAR image is firstly filtered by a speckle suppression algorithm and then a SIFT (Scale invariant feature transform) algorithm is used to extract feature points. Furthermore we use pyramid scheme, expanded correlation window and applying optimal gradient filter for compute the cross-correlation coefficient. The maximum value of cross-correlation coefficient defines the matching pixel. Finally, for the evaluation this method we use the epipolar geometry and compared the method with one of the classical methods. The result shows that our proposed method is superior to the classical approach in terms of accuracy and number of matched points.