Advertisement

License Plate Detection and Character Recognition

  • Fabio Caccia
  • Roberto Marmo
  • Luca Lombardi
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5716)

Abstract

In this paper we describe an approach based on infrared camera and novel methods about how to detect license plates on rear-side of a vehicle in still image or video stream. Particular contribution is posed on discovering plate area by edge search on each side of plate and reconstruction of rectangular shape. The recognized plate area is rotated and adjusted for a better character separation. Top hat morphological operator is used to extract characters from plate background. Each single character inside plate area is separated even in case of tilted shape. This approach try to slice the plate vertically, and it follow the character profile that hit on his vertical path. Pattern matching based on modified Yule dissimilarity measure is used for character recognition. Performance on 200 images are discussed.

Keywords

Character Recognition Infrared Camera License Plate Black Pixel Plate Area 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. 1.
    Barroso, J., Rafael, A., Dagless, E.L.: Number plate reading using computer vision. In: IEEE Intern. Symposium on Industrial Electronics, ISIE 1997 (1997)Google Scholar
  2. 2.
    Cowell, J., Hussain, F.: A fast recognition system fur isolated Arabic characters. In: Proc. Sixth International Conference on Infomotion and Visualisation, pp. 650–654. IEEE Computer Society, London (2002)CrossRefGoogle Scholar
  3. 3.
    Uk, D., Hwan, Y.: Implementation of pre-processing independent of environment and recognition of car number plate using histogram and template matching. Journal of Korean Institute of Communication Sciences 23(1), 94–100 (1998)Google Scholar
  4. 4.
    Fujiyoshi, S.H., Umezaki, T., Imamura, T.: Area extraction of the license plate using artificial neural networks. Trans. Of the Institute of Electronics, Information and Communication Engineers D-11 JSOD-11, 1627–1634 (1997)Google Scholar
  5. 5.
    Gonzalez, R.C., Wood, R.E.: Digital Image Processing. Addison Wesley, Reading (1993)Google Scholar
  6. 6.
    Gower, J.C.: Metric and euclidean properties of dissimilarity coefficients. Journal of Classification 3, 5–48 (1986)MathSciNetCrossRefzbMATHGoogle Scholar
  7. 7.
    Hontani, H., Koga, T.: Character extraction method without prior knowledge on size and position information. In: Proc. IEEE Int. Conf. Vehicle Electronics, pp. 67–72 (2001)Google Scholar
  8. 8.
    Hsieh, J.-W., Yu, S.-H., Cben, Y.-S.: Morphology-based license plate detection from complex scenes. In: Proc. 16 International Conference on Pattern Recognition, vol. 3, pp. 176–179 (2002)Google Scholar
  9. 9.
    Kim, H.J., Kim, D.W., Lee, J.K.: Automatic Recognition of a Vehicle License Plate using Color Image Processing. Engineering Design and Automation Journal 3(1) (1997)Google Scholar
  10. 10.
    Lee, S.-H., Seok, Y.-S., Lee, E.-J.: Multi-National Integrated Car-License Plate Recognition System Using Geometrical Feature and Hybrid Pattern Vector. In: Conf. Circuits/Systems. Computers and Comm., Phuket, Thailand, pp. 1256–1259 (2002)Google Scholar
  11. 11.
    Naito, T., Tsukada, T., Yamada, K., Kozuka, K.: License plate recognition method for passing vehicles outside environment. In: Int. Conf. Quality Control by Articial Vision, pp. 86–93 (1998)Google Scholar
  12. 12.
    Nijhuis, J.A.G., Brugge, J.A.G.: Car license plate recognition with neural networks and fuzzy logic. In: Proc. Int. Conf. Neural Network, vol. 5, pp. 2232–2236 (1995)Google Scholar
  13. 13.
    Postolache, A., Trecat, J.: License Plate Segmentation Based on a coarse Texture Approach for Traffic Monitoring System. In: Proc. IEEE Benelux workshop on Circuits, Systems and Signal Processing, Mierlo, The Netherlands, pp. 243–250 (1995)Google Scholar
  14. 14.
    Psoroulas, D., Loumos, V., Anagnostopoulos, N., Anagnostopoulos, I.E.: License Plate Recognition From Still Images and Video Sequences: A Survey. IEEE Trans. Intelligent Transportation Systems 9(3), 377–391 (2008)CrossRefGoogle Scholar
  15. 15.
    Sato, H., Ozawa, S., Komatsu, M., Kobayashi, A.: Motion blur correction of license plate images on running vehicle. Trans. IEE Japan  l17-C(6), 777–784 (1997)Google Scholar
  16. 16.
    Yu, M., Kim, Y.: An approach to Korean license plate recognition based on vertical edge matching. In: IEEE Int. Conference on Systems, Man, Cybernerics, vol. 4, pp. 2975–2980 (2000)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Fabio Caccia
    • 1
  • Roberto Marmo
    • 1
  • Luca Lombardi
    • 1
  1. 1.Dip. Informatica e sistemisticaUniversity of PaviaItaly

Personalised recommendations