OPALS – A framework for Airborne Laser Scanning data analysis

•We present a comprehensive framework for processing airborne LiDAR data, OPALS.•OPALS is a modular system. Complex work flows are enabled via scripting.•A data management component handles billions of points (coordinates and attributes).•Interoperability is ensured by providing interfaces based on industry standards.•The full potential of LiDAR can be exploited by enabling point cloud based processing.

A framework for Orientation and Processing of Airborne Laser Scanning point clouds, OPALS, is presented. It is designed to provide tools for all steps starting from full waveform decomposition, sensor calibration, quality control, and terrain model derivation, to vegetation and building modeling. The design rationales are discussed. The structure of the software framework enables the automatic and simultaneous building of command line executables, Python modules, and C++ classes from a single algorithm-centric repository. It makes extensive use of (industry-) standards as well as cross-platform libraries. The framework provides data handling, logging, and error handling. Random, high-performance run-time access to the originally acquired point cloud is provided by the OPALS data manager, allowing storage of billions of 3D-points and their additional attributes. As an example geo-referencing of laser scanning strips is presented.