Study On License Plate Recognition System

Recently the ITS (Intelligence Traffic System) has played an import role on the traffic. But now it is restrained more and more from some problems, such as the inactive structure of central system, the unsafety of operating system and software, the high cost of transference and the unsatisfactory performance of universal chip in image processing.One independent License Plate Recognition System has been designed to solve these worsening shortages. The professional image-processing chip C6711 of TMS320C6000 produced by the TI Company was used as the core in this system. In the front of system, Digital camera was used in image collecting. Data and order were transferred by Asynchronous Communications Interface.The software of the system mainly considered of two parts:1. Image segmentation. By studying, we concluded the arithmetic: first, summering the difference of neighboring points to ascertain the location of the license plate;then, projection was used to divide up the zone of license plate.2. Character recognition. The emendation of the leaning license plate in image is a key in this part. However none perfect way could recover owing to the complex causes and the difficult correction. Hough processing was used in this field and then the arithmetic, improved pattern matching, was used to identify the character in license plate.It can be showed in the experience that chip C6711 fulfilled the requests of the system and the system can work steady going and in high speed.