Algorithm for Car License Plate Location Based on Fractal Dimension of Waveforms
ZHUGE Bin1, 2, ZHOU HeQin2
1.College of Information and Electronic Engineering, Zhejiang Gongshang University, Hangzhou 310035 2.Department of Automation, University of Science and Technology of China, Hefei 230027
Abstract According to the distribution of the characters on a car license plate (CLP), a new location method based on distribution of fractal dimension of waveforms (FDW) is proposed in this paper. Using the method of sliding windows, the FDW for each line gray curve of every photo is estimated and two dimension distribution of FDW are gotten. Through processing the distribution of FDW, the CLP zone can be segmented easily. The experimental results show that FDW is effective for the attribute of the characters alignment on CLP and it is not affected by the background, the color and the type of CLP. Besides, the proposed algorithm is not sensitive to the sloping license plate and the accuracy rate of location for 1000 complicated background photos reaches 98. 9%.
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2006, Vol. 19 
