LiDAR Data Filtering and Digital Terrain Model Generation
This chapter concentrates on the generation of digital terrain models (DTM), also known as digital elevation models (DEM) from airborne Light Detection and Ranging (LiDAR) data. After a brief review on related basic concepts, this chapter presents a comprehensive discussion and evaluation on a number of representative filters for discrete return LiDAR and full-waveform LiDAR. Terrain reconstruction from full-waveform echoes is also discussed. To make a DTM or DEM usable for many disciplines, for example, hydraulics and geology, this chapter continues to address the derivation and simplification of terrain structure and feature lines. Finally, the quality of DTM from airborne LiDAR data is addressed based on a number of real-world examples, demonstrating the overall performance of the filtering algorithms and the need for future efforts.