License Plate Recognition System License Positioning And Pre-processing Technology

The Automatic License Plate Recognition System is a specific computer vision systembased on the specific goals of the vehicle license. It is composed with vehicle plate capture，vehicle plate recognition module, database management and data transfer through net etc. Thevehicle plate recognition module is composed with vehicle plate location, charactersegmentation and character recognition.The algorithm of vehicle plate location and license plate slant correction methodcombining mathematical morphology is studied systemically in this paper.In the pretreatment of the vehicle images, this paper plate image segmentation stage insome of the problems and put forward some good image processing technology.(1)Based onthe basic principle of the Otsu algorithm is presented and a new improved gray image ofbinary and the methods to static condition of extraction in 64 license plate, the simulationexperiment results show that the algorithm for ordinary license plates, their yellow licenseplate and the processing of the military license plate are effective.(2)By using the improvedSobel operator on license the morphological image edge detection and for the extraction ofthe 33 license plate the simulation experiment simulation experiment results show that thismethod can get more ideal license plate pre-processing image, more accurate positioninglicense plate provides help.In license plate location, this paper based on texture features to the positioning method,This paper used Sobel operator to the horizontal and vertical positioning, and also thepositioning of the +45 degrees and -45 degrees. After 22 license plate simulation results showthat the proposed method can be more clearly show the location of the license plate.Finally, this paper uses matlab programming constructs the license plate location software platform, at the same time for the vehicle images for acquiring a large number ofexperiments, obtain satisfactory results, for the follow up of license plate characterrecognition and division technology have laid a good foundation.