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BY 4.0 license Open Access Published by De Gruyter Open Access June 25, 2019

Feature extraction for license plate location based on L0-norm smoothing

  • Junqing Huang , Michael Ruzhanshy , Haoxiang Feng , Lingfang Zheng , Xin Huang and Haihui Wang EMAIL logo
From the journal Open Computer Science


We propose a simple feature extraction algorithm for license plate location, which can reduce the occurrence of pseudo-licenses significantly. Our scheme arises from a novel L0-norm image smoothing, in which the multiple local textures in the complex backgrounds can be suppressed remarkably without changing the structures and edges of the license objects. Due to this “edgeaware” property, we then combine a feature filtering with an efficient binarized image, a simple multi-scale image analysis algorithm, to remove the potential false license plates. Finally, we extract license plates with a projection method. Experimental results show the proposed method provides a flexible and powerful way to the license plate location in complex backgrounds.


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Received: 2018-07-10
Accepted: 2019-05-16
Published Online: 2019-06-25

© 2019 Junqing Huang et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution 4.0 Public License.

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