Gray projection-based license plate character segmentation method

Abstract

The present invention belongs to the computer vision field and relates to a gray projection-based license plate character segmentation method. According to the specific problem of license plate character segmentation, the objective of the invention is to improve the accuracy and reliability of license plate character segmentation and satisfy a requirement for real-time performance. The method includes the following two steps of: 1, removing the license plate borders of an input license plate area image: the upper border and lower border of a license plate are removed, and the left border and right border of the license plate are removed; and 2, segmenting license plate characters. With the method of the invention adopted, difficulties caused by complicated picture background, the influence of whether and illumination, the burring of license plate regions of the license plates of old vehicles and the license plates of illegal vehicles, and the like in an image processing process can be effectively eliminated, and therefore, the high reliability of the reading of license plate characters is high, the recognition of the license plate characters is high, robustness is good, step calculation is simple, high efficiency can be maintained, a requirement for real-time performance can be satisfied, the accuracy of the license plate recognition of a monitoring system is improved, and road traffic and parking lot vehicle management can be greatly promoted.

Description

Technical field [0001] The invention relates to the field of computer vision, in particular to a method for segmentation of license plate characters based on gray-scale projection. Background technique [0002] With the development of modern transportation, people pay more and more attention to the automatic recognition of vehicle license plates. It is one of the important research topics in the field of intelligent transportation in recent years by computer vision and pattern recognition technology. The automatic vehicle license plate recognition system can be used for vehicle management in road toll stations, parking lots, intersections, etc. It plays an important role in promoting road traffic and parking lot vehicle management. [0003] License plate recognition technology includes three basic links: license plate location, character segmentation, and character recognition. License plate location is the premise of character segmentation and character recognition, and license pl...

AI Technical Summary

Problems solved by technology

Third, in the actual collected pictures, many of the collected license plates are old car license plates or stolen car license plates, which causes the license plate area in the picture to be blurred, the color information of the license plate area is lost, and the characters of the license plate are stuck together, etc.

This increases the difficulty of license plate positioning, segmentation, and recognition.

Fourth, because most of the license plates on the vehicles on the road are produced under the standard GA36-1992, due to the impreciseness of this standard, the number plates produced under this standard have a wide range of chromaticity values. The above reason makes the chromaticity value distribution of the number plate obtained from the collection wide, thus increasing the difficulty for us to use the information

In the same license plate image to be segmented, several of the difficulties mentioned above may exist rather than a single difficulty. When several of these difficulties exist together, the difficulty it brings is not a simple process of addition. , so it is more difficult

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