Reconnaissance par vision du type d'un véhicule automobile

XAVIER CLADY; PABLO NEGRI; MAURICE MILGRAM; RAPHAEL POULENARD

TRAITEMENT DU SIGNAL

PRESSES UNIV GRENOBLE

Lugar: GRENOBLE, FRANCIA; Año: 2009 vol. 26 p. 31 - 46

0765-0019

Many vision based Intelligent Transport Systems are dedicated to detect, track or recognize vehicles in image sequences. Three main applications can be distinguished. Firstly, embedded cameras allow to detect obstacles and to compute distances from the equiped vehicle. Secondly, road monitoring measures traffic flow, notifies the health services in case of an accident or informes the police in case of a driving fault. Finally, Vehicle based access control systems for buildings or outdoor sites have to authentify incoming (or outcoming cars. Rather than these two systems, the third one uses often only the recognition of a small part of vehicle : the license plate. It is enough to identify a vehicle, but in practice the vision based number plate recognition system can provide a wrong information, due to a poor image quality or a fake plate. Combining such systems with others process dedicated to identify vehicle type (brand and model) the authentication can be increased in robustness. This paper adresses the identification problem of a vehicle type from a vehicle greyscale frontal image : the input of the system is an unknown vehicle class, that the system has to determine from a data base. This multiclass recognition system is developed using the oriented-contour pixels to represent each vehicle class. The system analyses a vehicle frontal view identifying the instance as the most similar model class in the data base. The classification is based on voting process and a Euclidean edge distance. The algorithm have to deal with partial occlusions. Tollgates hide a part of the vehicle and making inadequate the appearance-based methods. In spite of tollgate presence, our system doesn’t have to change the training base or apply time-consuming reconstruction process.