Study And Realization For License Plate Recognition System

With the develop of society-economic, the number of vehicles increase fiercely. Traffic problems have become increasingly prominent. This Intelligent Transportation Systems become a hot area of research. It has been widespread concerned. License Plate Recognition system is one of the most important field in intelligent transportation research.This paper, based on image characteristics license plate, has a deeply research to the key technologies of the vehicle license plate recognition system, which include three parts: digital image pre-processing, license plate location, license plate characters recognition.(1) In the vehicle images pre-procession, the paper use the methods of Histogram Transformation, Edge detection, binarization.(2) In the license plate location, a new algorithm is presented, using complicated texture,contrast and exterior to get the contrast energy, based on extremum region of convolution energy.(3) The paper use pattern matching which method has been improved to recognize the characters. Some of the characters closed to the main peak in vertical direction on the shape of the peak, but different in the level. So we can match the plate in the level .if the result which in vertical is unsatisfactory.