Dense stereo based critical area detection for an active pedestrian protection system

An active pedestrian protection system is required to operate in realtime and produce an extremely low false alarm. To achieve these requirements, Broggi et al. detected critical areas using a laser scanner and found pedestrians only in these areas via a camera. However, using heterogeneous sensors requires complicated system architecture and laser scanners have drawbacks in terms of installability and durability. Therefore, this letter proposes a critical area detection method using a stereo camera. This configuration can overcome the aforementioned drawbacks and detect both critical areas and pedestrians using a single sensor module. The proposed method detects critical areas by extracting local extrema of the depth change profile along a free space boundary. Experiments show its feasibility quantitatively.