License plate positioning method incorporating color, size and texture characteristic

Abstract

The invention belongs to the image processing technique field and particularly relates to the license plate identifying technique and further to a license plate locating method under a complex background. Firstly, a license plate original image of RBG format is converted into HSI format to realize the separation between color information and brightness information; then the obtained saturation component chart and brightness component chart are binarized; then pixels of the original image are classified according to the color information of the license plate and a license plate locating template binary image can be obtained according to the classification results and a mathematical morphology computing is adopted to remove noise from the license plate locating template binary image; then a region growing method is adopted to extract each communication zone of the license plate locating template binary image and an inspection to the license plate size is also carried out, and the communication zones passing the size inspection become candidate license plate zones; the Hough transformation is adopted to correct inclined license plates and then license plate vertical texture characteristics are adopted to further inspect each candidate license plate zone so as to remove the fake candidate zones. The adoption of the invention can effectively enhance the universality and the locating accuracy of the system.

Description

technical field [0001] The invention belongs to the technical field of image processing, in particular to a license plate positioning method in a complex background in the license plate recognition technology. Background technique [0002] Intelligent transportation is the main direction of the current traffic management development, and it is a frontier research topic in the field of transportation in the world. Automatic license plate recognition technology is the core of intelligent transportation system. It is an important means to solve the problem of expressway management, and it is the application of computer image processing technology and pattern recognition technology in the field of intelligent transportation. This technology is widely used in solving many problems on expressways, such as vehicle toll collection and management, traffic flow detection, parking lot toll management, violation vehicle monitoring, false license plate vehicle identification and other s...

AI Technical Summary

Problems solved by technology

The downside is that there are a lot of errors with the original image that introduces the text background

[0008] The common point of the above three license plate location methods is that these methods are all aimed at a specific feature of the license plate, and are easily limited by weather conditions, background, illumination and other factors, and their robustness is not good.

Once the conditions change, their segmentation accuracy will fluctuate greatly, so that the performance of the entire license plate recognition system will be greatly reduced.

Images