Vehicle license plate recognition method

Abstract

The invention provides a vehicle license plate recognition method, and relates to a method for image recognition. The method comprises the following steps of preprocessing an image; partitioning a vehicle region according to color and texture characteristics; extracting a remarkable factor graph of a vehicle region diagram; extracting candidate vehicle license plates by an Adaboost classifier based on expanded Harr-like characteristic; determining the position of a real vehicle license plate from the candidate vehicle license plates; partitioning the marked vehicle license plate from the corresponding vehicle region original diagram; carrying out character segmentation according to structural characteristic; and carrying out character recognition based on the improved template matching method. With the method provided by the invention, the defects that the application scene of the traditional vehicle license plate recognition method is relatively single, some traditional vehicle license plate recognition methods are only suitably used for single vehicle license plate recognition of the single scene and difficultly used for multiple-vehicle license plate recognition of multiple scenes, and the recognition rate is easily affected by strong light, haze and weak light environments are overcome.

Description

technical field [0001] The technical solution of the present invention relates to a method for recognizing graphics, specifically a method for recognizing a license plate. Background technique [0002] Intelligent Transportation System (Intelligent Transportation System, hereinafter referred to as ITS) helps to solve more and more vehicle management problems faced by traffic, and license plate recognition is an important part of the vehicle detection system in ITS, which can be applied to highway toll management systems, high-speed Highway speeding automatic supervision system, electronic police at urban traffic intersections, parking lot fee management system and other fields. [0003] The license plate location technology is the main link of the license plate recognition system. The more common method in the prior art is to use the color and texture information of the license plate combined with the morphological processing method to obtain the license plate area, but it i...

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved by the present invention is to provide a license plate recognition method, determine the vehicle area according to the prior knowledge of the color and texture features of the license plate itself, segment the vehicle area, and then use the relationship between the center pixel and its neighboring pixels to obtain the vehicle area. Regional saliency factor map, use the Adaboost classifier based on extended Haar-like features to obtain candidate license plates, verify the candidate license plates, complete the license plate location, and use the structural features of the characters to perform character segmentation for all the located license plates. The obtained 7 characters are recognized by the improved template matching method, which overcomes the single application scene of the existing license plate recognition method, and some are only suitable for a single license plate recognition in a simple single scene, and it is difficult to apply to multiple license plates in multiple scenes Recognition, the defect that the recognition rate is easily affected by strong light, haze and weak light environment

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