Differential perspective as a non-expensive distance sensing principle

Differential perspective is a simple and cost-effective monocular distance measurement technique that works by taking two images from two different (axially separated) locations. The two images are then analysed using image processing in order to obtain the change of size for different objects within the scene. Based on this information the distances to the objects can be easily computed. We use this principle to realize a sensor for assisted driving where the camera takes two images separated by 0.32 seconds. Distances to objects (e.g. number plates, traffic signs) of up to 200 meters can be measured with satisfactory accuracy. In the presentation we explain the basic principle and the employed image processing.