A Method for SAR Imagery Edge Detection Based on Ratio of Averages and Optimal Entropy

A method is proposed to automatically determine the threshold according to the image feature based on ratio edge detector instead of predefining it as before.The principle of optimal entropy into the edge detection of SAR image is introduced,which classifies the intermediate result image of ratio-based edge detector into two classes: edge and non-edge.The presented method performs simply and fast,needless of manual intervention,which can avoid the influence of human factors.