Contextual segment-based classification of airborne laser scanner data

authored by
George Vosselman, Maximilian Coenen, Franz Rottensteiner
Abstract

Classification of point clouds is needed as a first step in the extraction of various types of geo-information from point clouds. We present a new approach to contextual classification of segmented airborne laser scanning data. Potential advantages of segment-based classification are easily offset by segmentation errors. We combine different point cloud segmentation methods to minimise both under- and over-segmentation. We propose a contextual segment-based classification using a Conditional Random Field. Segment adjacencies are represented by edges in the graphical model and characterised by a range of features of points along the segment borders. A mix of small and large segments allows the interaction between nearby and distant points. Results of the segment-based classification are compared to results of a point-based CRF classification. Whereas only a small advantage of the segment-based classification is observed for the ISPRS Vaihingen dataset with 4–7 points/m2, the percentage of correctly classified points in a 30 points/m2 dataset of Rotterdam amounts to 91.0% for the segment-based classification vs. 82.8% for the point-based classification.

Organisation(s)
Institute of Photogrammetry and GeoInformation (IPI)
External Organisation(s)
International Institute for Geo-Information Science and Earth Observation - ITC
Type
Article
Journal
ISPRS Journal of Photogrammetry and Remote Sensing
Volume
128
Pages
354-371
No. of pages
18
ISSN
0924-2716
Publication date
06.2017
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Atomic and Molecular Physics, and Optics, Engineering (miscellaneous), Computer Science Applications, Computers in Earth Sciences
Electronic version(s)
https://doi.org/10.1016/j.isprsjprs.2017.03.010 (Access: Closed)
https://research.utwente.nl/en/publications/a7a03fd9-2c42-485c-bb64-3726a55879de (Access: Open)