The Study Of License Plate Recognition System Based On ARM

The system of auto license plate recognition is an important subject in the intellegent traffic field. It's also the trend of traffic management system in the future. A new auto license plate recogntion is designed in this article, it has the superiors of motobility, small volume, light weight, low energy and so on. Auto license plate recogintion is realized by utilizing ARM embeded technology to realise image adopting, image transmission and string recognition based on current technology of auto license plate in the fixed place and the wireless data transmission of GPRS.In the aspect of embeded system of hard ware, according to the function of this system, the hardware circuit is desigend which is centered by micro-controller S3C2410(ARM9 core) utilizing the embeded superiors which can be customised. It includes power circuit, clock circuit, memory circuit, image adopting circuit, image displaying and the interface of communication. In the aspect of software, according to the theory of divided layer of opertation system Windows CE and stream drive, the drive of USB camera and the image adopting are realised, then the image data are transmited utilizing the net of GPRS and ethernet.In the aspect of computer software, the image data are received by the Windows Sochets which is the brige of application and drive of ethernet, then the image data is transcacted. In the aspect of image transaction, the mean and algorithm is deeply introduced from initial image to final string recognition realising image graying, gray image stretching, image filter, edge detection, plate raw positioning, plate exact positioning, string partition, string recognition and finally acquiring the number of license plate.The information of vehicle is found and transmited to the traffic policemen according to the result of the recognition as the parameter which is compared with database.