Research On License Plate Location Algorithm Of License Plate Recognition System

With the development of information technology and intelligence technology, the informatization and intelligentizing of traffic management is the trend. License Plate Recognition system (LPR) is the core of Intelligent Traffic System (ITS). It is very important in modern traffic management systems. As a comprehensive real-time computer vision system, the vehicles license plate recognition (LPR) mainly includes the division of license plate localization and recognition of character. Because of the complexity of the scene, the unpredictability of license position and picture quality, the license plate localization division system is still something unsatisfied. Therefore the license plate localization division algorithm is always a hot spot of research in this field.A hybrid license plate location scheme that is based on mathematical morphology is presented in this paper, which is mainly implemented as following several steps. At first, we get the gray image of the license plate do the top-hat and the bottom-hat transformation, then, in first CCA (Connected component analysis) stage, we get rid of those non-text roughly according to the characters of license plate have the similar feature in height and size, and they also are connected with each other. Later, we connect these plate characters into one component based on finding the center line of them using Hough transform. Furthermore, the second CCA stage is accurately extracting the license plate according the real feature of the license plate.Based on the experiments dealing with images taken under various real world conditions, the results prove that this proposed method can relatively locate license plate. It shows that the performance of the system is promising, robust and timely.