Airborne analysis and assessment of urban traffic scenes from LiDAR data - Theory and experiments

This paper investigates the theoretical background for LiDAR to monitor traffic from airborne platforms. An object moving with a velocity deviating from the assumptions incorporated in the scanning process will generally appear both stretched and sheared - motion artifacts. To study the impact of these deformations in airborne laser scanning (ALS) data, the analytic relations between an arbitrarily moving object and its conjugate in the ALS data have been examined and adapted to concrete airborne specifications. A complete scheme is proposed to analyze urban traffic in real-life situations. This scheme combines vehicle motion classification method successively with vehicle detection. Furthermore, the velocity of moving vehicles can be derived. The algorithmic performance was assessed with respect to reference data concurrently obtained by video camera.