Vehicle license plate recognition method and system based on coarse positioning and fine positioning fusion

Abstract

The embodiment of the invention provides a vehicle license plate recognition method and a vehicle license plate recognition system based on coarse positioning and fine positioning fusion. The method comprises the steps that a positive sample set and a negative sample set of a vehicle license plate image are collected, Haar-like characteristics of the positive sample set and the negative sample set are extracted to train a vehicle license plate classifier, and a vehicle license plate region in an image to be detected is subjected to coarse positioning by using the vehicle license plate classifier; the vehicle license plate region subjected to coarse positioning is converted into a gray level image, vertical and horizontal projection information is analyzed to determine the upper and lower boundaries and the left and right boundaries of a vehicle license plate, and a vehicle license plate region subjected to fine positioning is obtained; a vehicle license plate character set comprising predetermined vehicle license plate characters is collected, a tesseract engine is used for analyzing the character characteristics of the predetermined vehicle license plate characters in the vehicle license plate character set and training to obtain a vehicle license plate character repertoire, the vehicle license plate region subjected to the fine positioning is identified by the vehicle license plate character repertoire, and characters in the vehicle license plate region subjected to the fine positioning are determined. According to the vehicle license plate recognition method and the vehicle license plate recognition system based on coarse positioning and fine positioning fusion, the problem that the positioning precision of the vehicle license plate is subjected to interference due to complicated background is solved.

Description

Technical field [0001] The invention is a digital image processing technology field, especially a license plate recognition method and system based on rough positioning and precision positioning. Background technique [0002] The license plate recognition system is an important part of the intelligent transportation system, and it is also a research hotspot in cross disciplines such as computer vision, digital image processing and pattern recognition.The license plate number is the only label in the world's identity recognition. The output of a license plate number of the size of the license plate through the license plate recognition system has unparalleled superiority in terms of storage space occupation or management database.In the management occasions such as large parking lots, highways, and toll stations of transportation departments, they all have extensive application prospects. [0003] The license plate recognition technology is mainly divided into two types: indirect ...

AI Technical Summary

Problems solved by technology

[0007] The embodiment of the present invention proposes a license plate recognition method based on the fusion of coarse positioning and fine positioning to solve the problem of interference with the positioning accuracy of license plates due to complex backgrounds, and to improve the accuracy and speed of character recognition

[0008] The embodiment of the present invention also proposes a license plate recognition system based on the fusion of coarse positioning and fine positioning to solve the problem of interference with the positioning accuracy of license plates due to complex backgrounds, and to improve the accuracy and speed of character recognition

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