Rooftop Detection Based on 3D Line Data Using Fast Graph Search

This paper highlights 3D building rooftop detection procedure based on 3D line data. Our approach begins with area-based stereo matching method to generate digital elevation map (DEM). Subpixel interpolation, normalized cross correlation and multi-resolution scheme are employed to generate an elaborate DEM. 3D lines are evaluated by using line fitting of DEM on 2D line coordinates of ortho-image. In order to use elevation in line fitting, the reliability of elevation is tested using self-consistency. 3D rooftop hypothesis is established by using an undirected graph, in which close cycles represent complete rooftops hypotheses. We test the proposed method with the synthetic aerial images. The experiment result shows that the extracted 3D rooftop realistically reflects real urban site model.