Journal of Applied Science and Engineering

Published by Tamkang University Press


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Kuo-Ming Hung This email address is being protected from spambots. You need JavaScript enabled to view it.1,2 and Ching-Tang Hsieh2

1Department of Information Management, Kainan University, Taoyuan, Taiwan 338, R.O.C.
2Department of Electrical Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C.


Received: December 3, 2008
Accepted: September 7, 2009
Publication Date: December 1, 2010

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In this paper we present a instant and real-time mobile vehicle license plate recognition system in an open environment. Using a nonfixed video camera installed in the car, the system tries to capture the image of the car in front and to process instant vehicle license plate detection and recognition. We utilize the color characteristics of the barking lights to carry out license plate detection. We first detect the location of the two barking lights in the captured image. Then set license plate detection region using the probability distribution of the license plate between the two lights. This method can eliminate any environmental interference during the license plate detection and improve the rate of accuracy of license plate detection and recognition. Moreover, we use the morphology method Black Top-Hat to enhance the level of separation of the license plate characters. Experiments show that the system can effectively and quickly capture the vehicle image, detect and recognize the license plate whether it is in daytime, nighttime, clear day, raining day or under complicated environment.

Keywords: Real-Time, Wavelet, License Plate, Black Top-Hat


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