  Smart and decentralized control systems have recently been proposed to handle
the growing traffic congestion in urban cities. Proposed smart traffic light
solutions based on Wireless Sensor Network and Vehicular Ad-hoc NETwork are
either unreliable and inflexible or complex and costly. Furthermore, the
handling of special vehicles such as emergency is still not viable, especially
during busy hours. Inspired by the emergence of distributed smart cameras, we
present a novel approach to traffic control at intersections. Our approach uses
smart cameras at intersections along with image understanding for real-time
traffic monitoring and assessment. Besides understanding the traffic flow, the
cameras can detect and track special vehicles and help prioritize emergency
cases. Traffic violations can be identified as well and traffic statistics
collected. In this paper, we introduce a flexible, adaptive and distributed
control algorithm that uses the information provided by distributed smart
cameras to efficiently control traffic signals. Experimental results show that
our collision-free approach outperforms the state-of-the-art of the average
user's waiting time in the queue and improves the routing of emergency vehicles
in a cross congestion area.
