DEM Generation and Building Detection from Lidar Data

This article explains the technique of DEM generation and building detection from Lidar (Light Detection and Ranging) data. Compared with traditional photogrammetry, lidar has advantages in measuring surface in terms of accuracy and density, automation, and fast delivery time. The author presents lidar as a companion technology for traditional photogrammetry. The direct product that can be derived from lidar data is the DSM (Digital Surface Model), which depicts the topography of the earth’s surface, including objects above the terrain. Further processing can be carried out to generate DEM (Digital Terrain Model) and object models like buildings, which is very useful information in telecommunication, city planning, flood control, and tourism. The author proposes a new method to extract ground points for DEM generation and to detect points belonging to buildings; a further strategy for boundary regularization is also proposed. The author concludes that these new methods for DEM generation and building detection are very efficient and effective, particularly in urban and suburban areas.