A Method for Precise Positioning and Rapid Correction of Blue License Plate

  • Jiawei Wu
  • Zhaochai YuEmail author
  • Zuchang Zhang
  • Zuoyong LiEmail author
  • Weina Liu
  • Jiale Yu
Conference paper
Part of the Smart Innovation, Systems and Technologies book series (SIST, volume 157)


To alleviate the problems of slow speed and weak correction ability of existing license plate correction methods under complex conditions, this paper presents a faster license plate positioning method based on the color component combination and color region fusion and develops a more accurate correction algorithm of blue license plate using probabilistic Hough transform and perspective transform. The proposed methods utilize the characteristics of white characters on the blue background of the Chinese license plate. Color component combination in HSV and RGB color spaces and image thresholding are first performed to obtain the background region of the blue license plate and its character region. Then, both regions are fused to obtain complete and accurate license plate region. And finally, edge detection, probabilistic Hough transform, and perspective transform are performed to achieve rapid license plate correction. Experimental results show that average correction time of blue license plate obtained by the proposed method is 0.023 s, and the average correction rate is 95.0%.


License plate positioning License plate correction Color component combination Color region fusion 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.College of Computer and Control EngineeringMinjiang UniversityFuzhouChina
  2. 2.Fujian Provincial Key Laboratory of Information Processing and Intelligent ControlMinjiang UniversityFuzhouChina
  3. 3.Department of Computer EngineeringFujian Polytechnic of Information TechnologyFuzhouChina

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