License Plate Detection and Recognition in Unconstrained Scenarios

  • Sérgio Montazzolli SilvaEmail author
  • Cláudio Rosito Jung
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11216)


Despite the large number of both commercial and academic methods for Automatic License Plate Recognition (ALPR), most existing approaches are focused on a specific license plate (LP) region (e.g. European, US, Brazilian, Taiwanese, etc.), and frequently explore datasets containing approximately frontal images. This work proposes a complete ALPR system focusing on unconstrained capture scenarios, where the LP might be considerably distorted due to oblique views. Our main contribution is the introduction of a novel Convolutional Neural Network (CNN) capable of detecting and rectifying multiple distorted license plates in a single image, which are fed to an Optical Character Recognition (OCR) method to obtain the final result. As an additional contribution, we also present manual annotations for a challenging set of LP images from different regions and acquisition conditions. Our experimental results indicate that the proposed method, without any parameter adaptation or fine tuning for a specific scenario, performs similarly to state-of-the-art commercial systems in traditional scenarios, and outperforms both academic and commercial approaches in challenging ones.


License plate Deep learning Convolutional neural networks 



The authors would like to thank the funding agencies CAPES and CNPq, as well as NVIDIA Corporation for donating a Titan X Pascal GPU.


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.Institute of InformaticsFederal University of Rio Grande do SulPorto AlegreBrazil

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