Fusion of airborne lidar point cloud and imagery captured from integrated sensor system

By fusing with other sensory data, especially high resolution imagery, LiDAR can be a good source of information for DEM extraction and feature extraction because it provides integrated information of geometric (surface), spectral and spatial property. Nowadays airborne LiDAR system vendors such as Leica and Toposys and others are providing systems with integrated camera capturing 3D point cloud and high resolution images simultaneously, for example, Leica's ALS50II, ALS60, and Toposys' FALCON II. The full potential of an integrated system in surveying and mapping has to be explored yet. In this paper, taking example of Toposys' FALCON data, we discuss some issues of data fusion: (1) cross sensor data registration, including geometric error budget; (2) two methods of fused data generation - imagery fused with range image re-sampled from point cloud and point cloud with assigned image pixel attributes. (3) Occlusion problem and how to solve it. We also show the segmentation results by a combined segmentation algorithm carried out on the fused multiple layer data. The results demonstrate the advantages of data fusion due to rich information and cues of objects in the fused data.