Automatic Urban Area Extraction From SAR Image Based on Morphological Operator

With the development of high-resolution spaceborne synthetic aperture radar (SAR) systems, it has been possible to use SAR data for identifying man-made structures in urban areas. In this letter, a new approach to extract urban areas in the SAR image is presented by using the morphological characteristics of the radar scattering mechanism. In order to detect the shape and location of a building, the radar shadow index and the double-bounce index are proposed. In addition, an automatic urban area extraction method is proposed using the fuzzy-based fusion of the morphological indices. The detection performance is evaluated by two X-band SAR data acquired from different systems. Despite the differences in observation and environmental conditions in the two data, the proposed method can provide consistent detection performance with the overall accuracy of about 88% and the Kappa coefficient of about 68%.