License plate positioning and identification method

Abstract

The invention provides a license plate positioning and identification method. The method comprises the following steps of acquiring an original image snapshot by a camera; using a preset zoom coefficient to zoom the original image for many times so as to acquire a plurality of zoom images, and detecting a license plate area image in each zoom image; mapping the detected license plate area images to the original image, through filtering, merging and superposing images, according to a characteristic intensity of each license plate area image, ordering the license plate area images and acquiring all the license plate area images; carrying out downsampling on all the license plate area images for one time, carrying out graying, vertical edge detection and binaryzation on the downsampled images, and using vertical edge information to carry out license plate coarse positioning and acquiring all the license plate areas; correcting a gradient of the license plate areas; carrying out character segmentation on the license plate areas; and identifying segmented characters. Through the above mode, a license plate can be identified in a high-definition image.

Description

technical field [0001] The invention relates to the technical field of license plate automatic recognition, in particular to a license plate location and recognition method. Background technique [0002] With the development of the economy, the number of cars has increased sharply, and the management requirements for traffic and public security are also increasing. Using high-definition camera imaging technology, it can not only capture the license plate clearly, but also provide high-quality images of the faces of the drivers and passengers in the front row. And it can record the whole picture of the vehicle and the information on the vehicle, so as to meet the needs of multiple business departments such as criminal investigation, public security, and traffic police. In addition, with a camera with 2 million or higher pixels, one camera can capture 2-3 lanes, and the system construction efficiency is also significantly improved. Therefore, high-definition license plate rec...

AI Technical Summary

Problems solved by technology

[0003] The existing standard definition image license plate recognition method is difficult to be used for high definition image license plate recognition

The reason is that the license plate recognition of high-definition images has high resolution, wide viewing range, complex background, and difficult license plate positioning. There are multiple license plates in the image that need to be recognized at the same time, while the existing standard-definition image license plate recognition generally only recognizes a single background. single license plate

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