Illumination-invariant change detection for the protection of vehicle convoys

The detection of potential threats such as IEDs is essential for the security of military vehicle convoys. We present an image change detection approach that estimates change probabilities in outdoor routes, using a monocular optical camera system. The camera system is part of a multi-sensor system mounted on the lead vehicle of a vehicle convoy, and the estimated change probabilities of each sensor are exploited by a data fusion algorithm. Our change detection approach is based on illumination-invariant image representations and is thus insensitive to illumination differences (e.g., due to shadows), and detects potential changes of multiple sizes. We introduce a temporal weighting scheme based on intra-sequence homography coherence to reduce false detections due to the parallax effect. For the experimental evaluation we have used image sequences acquired on outdoor routes which include different types of changes, strong illumination differences, and scenes with parallax.