Building identification from SAR image based on the modified marker-controlled watershed algorithm

Detailed information about a building and its surrounding is generally contained in hi-resolution synthetic aperture radar (SAR) data. An approach to extract the information and to identify the building with linear features from a single hi-resolution SAR image has been developed. With the strong radar backscattering and shape feature of a building in SAR image, external markers were derived by an OTSU algorithm and a morphology algorithm. Then the minima imposition technique was used to modify the edge-enhanced SAR image coupled with the markers. Finally, the linear building boundaries were obtained using the watershed algorithm. Results of building extract from three types of developed areas were satisfactory.