License Plate Recognition Under Nonuniform Illumination

  • Ren-Chao Shen
  • Day-Fann Shen
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 234)


License plate recognition (LPR) is an important technique in automobile management and traffic control. Experiments show that the recognition rate dropped significantly when the illumination on the license plate is nonuniform. In this chapter, we proposed a simple block-based method to resolve the problem. Experiments show that the proposed method is not only fast but also outperforms well-known Otsu as well as state-of-the-art NiBlack and MAT, with recognition rate of 86% for the 100 nonuniformly illuminated license plate test images.


License plate recognition Registration Block based Edge detection Nonuniform illumination Character segmentation Character recognition 


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of Electrical EngineeringNational Yunlin University of Science and TechnologyYunlinTaiwan

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