Automatic License Plate Recognition as suitable tool to generate real-time traffic data as input for route decisions in smart traffic management

摘要

Traffic management integrates traffic information and traffic control. Its aim is to use the existing road infrastructure the best way possible and adapt it to the current traffic situation. That means to anticipate and identify free capacities and to act strategically by using all kinds of actuators and all information about the traffic state that is available. One important use case is strategic route choice information via variable message signs (VMS) or C2C communication systems. The ideal basis for traffic information for this case is Automatic License Plate Recognition (ALPR), because it’s the only tool available that can really detect and measure travel times on the routes that are to be suggested to the driver. ALPR systems (containing of ALPR cameras, data processing units and specialised license plate recognition software) at specific points within the road network are taking images of the license plates of all the passing vehicles. After processing the images the data strings - containing the plate number, time and location ID – are transferred to the network control system. The ALPR systems delivers data to the network control system to obtain real time information about travel time, origin destination and performance monitoring. This paper examines the measures and preconditions that need to be fulfilled for a thorough usage of ALPR in strategic route management systems.