Research On Algorithm Of Detecting Edges Applying To License Plate Location System

Based on the technology of recognizing images and characters, the vehicle license plate recognition system is a kind of intelligent transportation management system. Such systems, which are applied in parking areas, highways, bridges and tunnels, can help a human operator and improve the overall quality of a service. Automatic detection and recognition of vehicle license plates mainly includes the subsystem of license plate location and character recognition. The location of license plates is the key of the system. Because of the complex of image background, the uncertainty of plate position and image quality, the location of plates is not satisfied. Therefore, the study on the algorithms of license plate location is always the hotspot problem. The system has very big economy value and practicality.Above all, familiar image processing methods were processed analyzing and experiment. In the system of license plate location, we used two modules block answer the image preprocessing and image of edge detection and intersected, programme and experiment were done for several methods. Based on the need of system, we carried through essential improvement, proposed a new algorithm for perpendicular edge detection, it can beautiful extrude license plate provincial characteristics.Secondly, in this paper a new arithmetic of perpendicular edge detection work on license plate location, according to statistical features of perpendicular edge which belong to license plate provincial characteristics, from the image, it can confirm the likelihood license plate inquire electoral district. Utilization the speciality of geometrical shape, we can filter the license plate inquire electoral district, then located the license plate location. The arithmetic had a very good result for experiment in the image database.Afterward, availing image cutting method and morphologic's etching method, in the system, we designed two model blocks normalization and thinning. Finishing the connecting from location to discriminating.At last, according to the above research, license plate location system software is developed in the environment of Visual C++. The software is characterized by modularization, visualization and simple use. Result of this software is good.