Integrated Full-Waveform Analysis and Classification Approaches for Topo-Bathymetric Data Processing and Visualization in HydroVISH

Topo-bathymetric LiDAR data captured with modern systems are complex. The primary information received is a time-dependent amplitude variation of the reflected light. These so-called waveforms are processed into singular points with 3D coordinates by advanced on-board devices of the LiDAR sensor (online waveform processing), but the full-waveform (FWF) information may be available as well. However, available software tools are often insufficient to manage all required processing steps. Common file formats do not allow to store originally recorded sensor parameters together with subsequently processed parameters in one database or file. The FWF, however, can contain information to better cover the terrain below dense vegetation, and to improve aerial coverage of the water ground. Thus, we extended the software suite HydroVISH with respect to an integrated FWF processing pipeline. Employing the open-source Hierarchical Data Format V5 (HDF5) with the F5 layout thereby allows for efficient data storage and handling throughout the processing chain. The potential benefit of performing a comprehensive FWF analysis can be assessed via the simultaneous visualization of the complete FWF information on all points in an interactive display environment. Next, the valuable point information is extracted using various provided FWF processing tools, such as Richardson–Lucy deconvolution or Gaussian decomposition. For topo-bathymetric data, the correct point classification of the terrain above and below water as well as the actual water surface is crucial to correctly calculate the refraction correction for points beneath the water surface. Finally, we also outline the implemented classification approach for the terrain and water surface.