Fig. 3
From: Towards automatic near real-time traffic monitoring with an airborne wide angle camera system
Examples for road extraction (clipping from nadir images). Upper panel shows line detections at a flight height of 1,000 m, middle panel shows the resulting road area after smoothing/gap filling (A 96 near exit Munich-Blumenau, GSD of 15 cm). Lower panel shows the resulting road extraction on an image obtained at a flight height of 1,500 m (motorway A 4 near Dresden, GSD of 21 cm)