Method and system for traffic performance analysis, network reconfiguration, and real-time traffic monitoring

Abstract

A method and system for traffic performance analysis, network reconfiguration, and real-time traffic monitoring and surveillance is described. Traffic performance analysis and congestion detection is achieved through discrete event simulation. The road network is translated to a graph. The translation is the result of the processing of a high resolution satellite or aerial image consisting of road extraction. In the resulting graph, road intersections are represented by vertices and road sections by edges. Edges have several properties such as the capacity of the section, presence of traffic signs and traffic lights, rate of generation (vehicles leaving parking), and rate of absorption (vehicles going to parking) Temporal simulation allows detecting congestions as well as congestion propagation. Real-time traffic monitoring consists of detecting abnormal traffic slowdowns. This is achieved by observing traffic with a camera. The video is processed to compute the optical flow which allows the computation of the traffic speed. Individual vehicle speed is also computed to detect speeding vehicles by comparing their speed to the nominal speed limit in the road section. The whole system can be grouped in a traffic control room or a traffic information system.

What is claimed is: 
     
         1 . An intelligent transportation system, comprising:
 an augmented graph data depicting an urban road network;   a memory for storing the augmented graph data;   a discrete event simulator using the augmented graph data to check if a congestion has been solved;   a plurality of cameras placed on critical road sections;   a plurality of displays showing videos captured by the cameras;   a device for controlling traffic lights and variable-message signs; and   a server running the discrete event simulator and processing the camera video streams in real time for real time surveillance.   
     
     
         2 . The intelligent transportation system according to  claim 1 , wherein the augmented graph data is originated from a high resolution satellite or an aerial image, the high resolution satellite or the aerial image being used for road extraction. 
     
     
         3 . The intelligent transportation system according to  claim 2 , wherein information of the augmented graph data comprising signaling, road capacity, and speed limits. 
     
     
         4 . The intelligent transportation system according to  claim 1 , wherein the device controls traffic lights and variable-message signs is an automatically or a manually controlling device. 
     
     
         5 . A method for detecting congestions, enhancing traffic performances, and real-time traffic surveillance, comprising:
 obtaining an augmented graph data depicting an urban road network;   detecting congestion by the augmented graph data;   updating locally road signs and signaling to alleviate congestion;   verifying if the congestion has been solved by using a discrete event simulator;   installing a plurality of cameras along the road;   monitoring traffic flows by videos recorded by the cameras; and   changing the timing of traffic lights or modifying electronic traffic signs to solve traffic congestion.   
     
     
         6 . The method for detecting congestions, enhancing traffic performances, and real-time traffic surveillance according to  claim 5 , wherein the augmented graph data is originated from a high resolution satellite or an aerial image, the high resolution satellite or the aerial image being used for road extraction. 
     
     
         7 . The method for detecting congestions, enhancing traffic performances, and real-time traffic surveillance according to  claim 5 , wherein detecting congestion comprising:
 processing videos to compute optical flows; and   computing traffic speed from the optical flow.   
     
     
         8 . The method for detecting congestions and enhancing traffic performances according to  claim 6 , wherein information of the augmented graph data comprising signaling, road capacity, and speed limits. 
     
     
         9 . The method for real-time traffic surveillance according to  claim 5 , wherein changing the timing of traffic lights or modifying electronic traffic signs to solve traffic congestion is operated manually or automatically.