• 2020 (Vol.34)

Segmentation of vehicle registration plates based on dynamic time warping

© 2018 M. A. Povolotskiy, E. G. Kuznetsova, N. V. Utkin, D. P. Nikolaev

Institute for Information Transmission Problems RAS 127051 Moscow, Bolshoi Karetny per., 19

Received 09 Aug 2017

A fast number plate segmentation algorithm for automatic license plate recognition system is proposed. It is robust to inaccurate plate quadrangle localization, as well as image brightness distortion. The algorithm uses a priori information about standard plate types geometry and additionally adjusts symbols positions by estimation and correction of localization error. A plate localization error model is built. Its optimal parameters are computed effectively through dynamic programming. Also an algorithm modification is suggested for simultanious segmentation and optimal type selection from a known set. Experimental results are presented to demonstrate the efficiency of this approach.

Key words: license plate recognition, license plate segmentation, dynamic time warping, dynamic programming

DOI: 10.7868/S0235009218010080

Cite: Povolotskiy M. A., Kuznetsova E. G., Utkin N. V., Nikolaev D. P. Segmentatsiya registratsionnykh nomerov avtomobilei s primeneniem algoritma dinamicheskoi transformatsii vremennoi osi [Segmentation of vehicle registration plates based on dynamic time warping]. Sensornye sistemy [Sensory systems]. 2018. V. 32(1). P. 50-59 (in Russian). doi: 10.7868/S0235009218010080


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