Sequential Image Analysis of Vehicle Maneuvers : Evaluation of Vehicle Position Accuracy and Its Applications

Sequential images from high altitude platforms are suitable for traffic flow surveillance, which requires fixed-point continuous observation of vehicle movements over a wide area. The authors have developed a vehicle maneuver recognition method using these images, and confirmed its effectiveness. The method, however, required adjustments to some parameters, depending on the images. In addition, the results were given in image coordinates (pixels) instead of real world coordinates. This paper describes a method to adjust the parameters and a framework to evaluate the vehicle positioning accuracy using real distances. The proposed framework is applied to real sequential images obtained from a helicopter, and the vehicle positioning accuracy is estimated. The sequential images have 30 cm spatial resolution and 1/30 s time resolution. The framework provides exact and efficient vehicle recognition. The positioning accuracy of the recognized vehicles is better than 1.92m.