A Measurement of Velocity for a Group of Vehicles using Spatio-Temporal Image

Abstract

Traffic flow measurement sensors, which measure vehicle velocity and detect traffic accidents, traffic congestion and so on using image processing, have been installed. Image processing methods are based on recognizing each vehicle. However, in the case where cameras are set up at low positions such as in tunnels, it is difficult to measure vehicle velocity in heavy traffic conditions because one vehicle often blocks the view of another in the images. To overcome this drawback, we propose a method for measurement of velocity for a group of vehicles. The method utilizes DTT method which transforms spatio-temporal image to 2-D data onto a directional-temporal plane, and measures moving time of a group of vehicles by matching patterns of DTT data at some points. We describe the method and also show the experimental results using road images.