Airborne Laserscanning and Interferometric SAR
EuroSDR Distance Learning Course
Filtering and Classification of Laser Scanner Data
This document is a part of the EuroSDR distance learning course on the generation of digital terrain modelds (DTMs) from Interferometric SAR and Laser Scanner data. This unit is concerned with the filtering of laser scanner points for DTM determination. Airborne laser scanning (ALS) is also known as LiDAR (Light Detection And Ranging).
This excercise is organized in a Tour
First an introducation to the necessary theory will be given. This includes general remarks on the terrain interpolation (Linear Prediction) and the classification of the laser points (Hierarchic Robust Interpolation).
This is followed by an introduction to SCOP++, a DTM modelling software package, will be given. It is developed by the Department of Geodesy and Geoinformation, Vienna University of Technology and INPHO GmbH. Within this package the filtering of laser scanner points, also termed "classification" is possible. The points are classified into terrain points (also known as ground points) and into off-terrain points (sometimes falsly also called vegetation points). The graphical user interface (GUI) for the classification and interpolation will be presented.
In the next steps of the tour the filtering is demonstrated by two examples. The data sets of Vaihningen and Stuttgart, including check points, are provided by EuroSDR. Data capturing was performed by Fotonor with an Optech Scanner for both areas, and laser data over Stuttgart was also provided by TopoSys. The check points were measured by the Institute of Photogrammetry, University of Stuttgart.
In the course of the "EuroSDR Workshop on Airborne Laserscanning and Interferometric SAR for Detailed Digital Terrain Models" a paper was published describing the principles of the filtering approach. In the corresponging EuroSDR Publication No. 40 further different algorithms for the classification of ALS data and applications can be found. Other publications can be found in the Link collection.