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| A New Vehicle Licence Plate Recognition Method Based on MSER and SWT |
| WANG Yan,XIE Guang-su,SHEN Xiao-yu |
| School of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China |
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Abstract In order to reduce the influence of camera distance and the light on license plate recognition, improving the recognition accuracy of license plate with complex background, a new license plate recognition method based on maximally stable extremal regions (MSER)and stroke width transform(SWT) has been proposed. Firstly, the MSER extraction and Canny edge detection are carried out and the filter of the MSER based on geometric features of license plate character is conducted, then the SWT and SW selection of the selected areas is conducted based on morphological processing, the selected regions are gathered and the license plate is located combined with their features. Finally, the segmentation of the location region is checked and its skeleton are extracted and normalized, then, it is matched with the thinned and normalized template. The first character Chinese characters are recognized by HU invariant moments and grid features, and the digits and letters are identified by scanning skip point statistics code. Experiment results show that the accuracy of the location is as high as 94.86% and the accuracyof the recognition is as high as 96.92%, which indicates that this method has high accuracy and robustness for license plate detection and recognition in complex background with long distance and variable illumination.
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Received: 26 October 2017
Published: 07 January 2019
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2019, Vol. 40 
