A Blue License Plate Segmentation and Correction Method

Abstract

The present invention relates to a blue license plate segmentation and correction method, comprising the following steps: 1. For the rough positioning image of the license plate, the R channel map of the RGB channel and the V channel map of the HSV color space are used to construct a combined image, and then the highlighted blue license plate is obtained. The blue area binary image of the colored area, and then fuse it with the white area binary image highlighting the white character area of ​​the license plate to obtain a dual-area fusion binary image; 2. Perform edge detection on the dual-area fusion binary image, here On the basis of obtaining the binary image of the circumscribed contour of the license plate area, then the probabilistic Hough transform is performed on the binary image of the circumscribed contour of the license plate area to fit the contour line segment and further locate the corner points of the license plate; 3. After obtaining the corner points of the license plate, the original The license plate image is subjected to perspective transformation to obtain the rectified license plate image. This method can quickly and accurately correct the license plate under complex conditions and improve the recognition rate of the license plate.

Description

technical field [0001] The invention relates to the technical field of image processing, in particular to a blue license plate segmentation and correction method. Background technique [0002] The license plate recognition system is a key component of the intelligent transportation system, which has a wide range of application scenarios, such as car anti-theft, traffic flow control, parking lot toll management, red light electronic police, road toll stations, etc. The general steps of the license plate recognition system can be divided into rough license plate positioning, precise license plate positioning, license plate correction, and license plate character recognition. Each step in the license plate recognition system is closely related, among which the precise positioning of the license plate and the correction of the license plate have a great influence on the accuracy of the license plate character recognition. Zheng Kaipeng, Zheng Cuihuan, etc. proposed a rapid lice...

AI Technical Summary

Problems solved by technology

The method based on the traditional Hough transform relies on the frame of the license plate to determine the angle of inclination, and the correction cannot be completed for the case where the characters stick to the frame and there is no frame of the license plate

The method based on Radon transform also has the defects of large amount of calculation, slow speed, and inability to adapt to some complex conditions.

These methods are difficult to complete the tasks of accurate license plate positioning and real-time correction of license plates under complex conditions.

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