Contourlet-Based Edge Extraction for Image Registration

Image registration is a crucial step in most image processing tasks for which the final result is achieved from a combination of various resources. In general, the majority of registration methods consist of the following four steps: feature extraction, feature matching, transform modeling, and finally image resampling. As the accuracy of a registration process is highly dependent to the feature extraction and matching methods, in this paper, we have proposed a new method for extracting salient edges from satellite images. Due to the efficiency of multiresolution data representation, we have considered four state-of-the-art multiresolution transforms –namely, wavelet, curvelet, complex wavelet and contourlet transform- in the feature extraction step of the proposed image registration method. Experimental results and performance comparison among these transformations showed the high performance of the contourlet transform in extracting efficient edges from satellite images. Obtaining salient, stable and distinguishable features increased the accuracy of the proposed registration process.