CFAR Edge Detection Using Hysteresis Thresholding for Polarimetric SAR Imagery

Edge detection is highly susceptible to streaking caused by speckles in polarimetric synthetic aperture radar (PolSAR) imagery. In this article, we address hysteresis thresholding for suppress streaking in PolSAR's edge detection. As an example, an approach is suggested by combining the constant false alarm ratio (CFAR) detector and the hysteresis thresholding. After thinning edges obtained by the CFAR detector, the hysteresis thresholding is employed to reduce edge streaking, which is caused by abundant speckles. A ratio of the high to the low threshold P-fa in the hysteresis thresholding is pointed out for linking edges. Experiments are carried out on both simulated and real PolSAR data sets, and the results reveal that hysteresis thresholding obviously promotes the performance of the CFAR detector.