Method for recognizing characters of licence plate based on Haar-like feature and support vector machine

Abstract

The invention provides a method for recognizing characters of a licence plate based on a Haar-like feature vector and a support vector machine (SVM), belonging to the fields of pattern recognition and intelligent transportation, and relating to character image feature extraction and character classifier training. The method for recognizing the characters of the licence plate is the core technology of licence plate recognition, wherein two key problems to be solved are character feature extraction and design of a character classifier. In the invention, a Haar-like feature structure appropriate for the stroke width of a character is selected to describe a stoke of the character, and the Haar-like feature structure membership degree of a character image block is extracted to construct a feature vector for character recognition so as to train a SVM character classifier with good generalization performance. The geometric structure of the character is a key feature for the character recognition, and the geometric structure of the stroke is converted into a statistic value to describe the stroke, which is innovation of the invention. The method for recognizing the character image of the licence plate provided by the invention has good anti-interference performance, can be used for recognition of the characters of the licence plate in a traffic video and has the characteristics of good instantaneity and high recognition accuracy.

Description

technical field [0001] The invention belongs to the field of pattern recognition and intelligent transportation, and relates to image feature extraction and character classifier training. The present invention proposes a new method for character recognition of license plate images based on Haar-like eigenvectors and a Support Vector Machine (SVM) classifier, which is used for character recognition of license plates in traffic videos, and has good real-time performance and high recognition accuracy The characteristics. Background technique [0002] Intelligent transportation system is a new generation of transportation system that emerged in the 1990s, and there is no internationally accepted definition so far. The First World Conference on Intelligent Transportation Systems believes that intelligent transportation systems are the effective integration and application of advanced information technology, computer technology, data communication technology, electronic control t...

AI Technical Summary

Problems solved by technology

Commonly used character statistical features include moment and frequency domain features, and commonly used character structure features include run-length features, LBP features, and Gabor features; however, it is difficult for any of these features to have both high recognition rate and high recognition speed

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