A License Plate Extraction Algorithm Based on Edge Statistics and Region Growing

  • Manuel Vargas
  • Sergio L. Toral
  • Federico Barrero
  • Francisco Cortés
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5716)


This paper presents a license plate extraction method for gray-scale images, based on a combination of edge statistics and a two-step seeded region growing algorithm. The proposed region growing algorithm uses a dual criterion based on edge density and gray-scale intensity affinity. The proposed method aims at achieving license plate segmentation that fits to the real plate boundaries better than existing methods. The robustness of the method has been tested with experimental results, including examples of low quality or poor-preserved plates and commercial or freight transport vehicles.


Automatic License Plate Recognition (ALPR) plate localization edge statistics seeded region growing 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Manuel Vargas
    • 1
  • Sergio L. Toral
    • 1
  • Federico Barrero
    • 1
  • Francisco Cortés
    • 1
  1. 1.E. S. IngenierosUniversity of SevilleSevilleSpain

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