Abstract
This paper proposes a new method of LIDAR data processing to automatically extract building and 3-D city modeling. This method exploits image processing technique including Hough transformation. The process of building extraction starts with DSM segmentation according to elevation values. Among these fragments, extracting process limits candidates of building fragments to those that have elevation higher than a specified threshold value and the DEM at the same location. Hough transformation is executed to boundary pixels of each candidate of building fragment and then fit to linear segments. Edges in corresponding parts of aerial images can also be used to refine boundaries of buildings. Each fragment is polygonized with these line segments. After the extraction, 3-D-building model is created with these polygons such that each polygon has vertical wall from the top of building to the ground (DEM) . Texture images are pasted onto each building, including walls. The most appropriate texture image is selected from aerial images according to geometry between building faces and external parameters of the photos. The method has been tested with LIDAR data of Shinjuku and Ginza area in Tokyo.
