Building collapse extraction using modified freeman decomposition from post-disaster polarimetric SAR image

Abstract

It is still a challenge to obtain the collapsed building distribution from post-disaster polarimetric synthetic aperture radar (SAR) data. This paper proposed a novel approach for extracting the spatial distribution of collapsed buildings using post-disaster RADARSAT-2 SAR data. In this method, non-building areas are removed by using eigen-values λ2 + λ3. Then, the modified Freeman decomposition which includes deorientation selectively and surface scattering characteristic parameter constraint is presented for building area. The contribution of the double-bounce component (PD/span) is used to extract the collapsed building spatial distribution. The method was tested on RADARSAT-2 fine-mode polarimetric SAR imagery from the Yushu earthquake which acquired on April 21, 2010. By comparison with other methods, the results confirm the validity of the proposed method.