SAR Image Edge Detection by Ratio-based Harris Method

The presence of speckle, which modeled as a strong multiplicative noise, makes the edge detection of synthetic aperture radar (SAR) images very difficult. The usual edge detectors using gradient yield poor results. By analyzing Harris´ combined corner and edge detector, to solve the speckle-sensitivity and anisotropic response, an edge detection method used for SAR image is presented. Horizontal, vertical and diagonal ratios of averages of non-overlapped neighboring pixel values instead of gradients are used to calculate edge strength maps (ESM); then they are fused to obtain the final ESM; finally, a threshold is presented to obtain edge detection result. Analysis and experiment results illustrate that the proposed method can be used for edge detection in SAR image effectively