WATCH MECHANISM: MOTORWAY TRAFFIC MONITORING
Roberto Moro, Davide Bogni · Traffic Technology International · 2000
When video processing techniques are applied to monitor traffic flow automatically, each peripheral processor generates a data set linked to its own observation point. Each sensor records and transmits any variations monitored with respect to a sensitivity threshold. A processing station includes a variety of cameras, image processors, and other equipment, and typically measures average speed, volume, occupancy, deceleration, queues, gaps, stopped vehicles, etc., in each traffic lane. Project Automation, the Italian video processing system integrator, very recently concluded a wide area assessment of its system on a stretch of inter-urban motorway in Italy. This article describes this system and the assessment, and includes examples of its video camera pictures. In the system, vehicles are detected using an algorithm which detects and processes differences in grey tone between image background and the image of a travelling car. The central system aims to provide clustered analyses of single events, so that knowledge of local traffic data can be used. It manages the system peripherals, video cameras, and variable message signs (VMS). The graphic user interface provides a selection of functions and operating models. The system's representation of itself must reflect its components and their modifications.