Strategic Study of CAE >> 2004, Volume 6, Issue 3
A Method for License Plate Localization based on Texture and Wavelet Analysis
Engineering Research Center for Intelligent Transportion Systems under Ministry of Education , Southeast University , Nanjing 210096 , China
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Abstract
This paper presents a method for vehicle license plate localization using texture and wavelet analysis. In view of the complex background and the small ratio of the license plate area to the whole picture, a method for finding a threshold for primitive classification is proposed. According to the distribution regularities of the characters in the license plate, a binary texture primitive analysis method is presented to extract the candidate license plate areas. A feature of the vertical strokes in the license plate is extracted using wavelet analysis. The feature of the vertical strokes, position feature and shape feature are quantificationally evaluated using membership degree, and a method for selecting the license plate area from the candidates by integrating all the features is described. A test shows that the proposed method offers a localization correctness rate of higher than 96% .
Keywords
texture ; wavelet analysis ; primitive ; license plate localization
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