Design And Implementation Of License Plate System Based On Image Recognition

The image based license plate recognition system is an important application of computer vision and pattern recognition technology in the intelligent transportation system.It is mainly used in the monitoring of the vehicle video,the intelligent management of the parking lot,and the electronic police.Therefore,the success of license plate recognition system is playing an increasingly important role in improving traffic,especially in increasingly congested traffic.The main algorithm of image based license plate recognition system consists of three parts: license plate location,license plate character segmentation,license plate character recognition and so on.In this paper,license plate recognition algorithm is investigated and summarized,combined with the actual situation,some improvement suggestions are put forward,and a simple license plate recognition system is implemented.It involves the following:1.research license plate image positioning algorithm.In this thesis,the common license plate location algorithm is studied.In particular,it is difficult to locate the license plate when the license plate is not clear and the lighting condition is not good.An optimized edge detection operator's license plate location algorithm is proposed,which realizes the texture feature extraction in the direction of transverse,longitudinal and oblique angles.The threshold value of the two value image is calculated by mathematical morphology,and the candidate area of the license plate is obtained.Finally,the pseudo license plate is removed according to the license plate characteristics.2.the segmentation algorithm of license plate image is studied.The common segmentation algorithms are studied,including the projection based license plate segmentation algorithm,the plate segmentation algorithm based on the template matching,and the character segmentation algorithm based on the clustering analysis.3.research license plate image recognition algorithm.The license plate character recognition algorithm based on classifier and feature statistics is studied,and the characteristics of BP neural network classifier are studied.4.a simple recognition and recognition system of license plate character is realized.A simple license plate character recognition system is implemented by license plate location algorithm,license plate image segmentation algorithm and license plate image recognition algorithm.