An Improved Method for Vietnam License Plate Location based on Mathematic Morphology and Measuring Properties of Image Regions

Abstract:

In the Automatic License Plate Recognition (ALPR) system, the License Plate Location (LPL) is the key step before the final recognition. This paper proposed an improved LPL algorithm for Vietnam vehicle license plates (LP). The proposed algorithm consists of three main modules: Pre-processing (convert RGB image to grayscale image, adjust grayscale image intensity, image binarization use Otsu method), LP candidates location (morphology opening to remove noises & dilation operation, measure properties of image regions to find candidates), LP exactly location (finding the LP angle & rotating LP, cut exactly LP region). We implemented test for 350 Vietnam vehicle images, which obtained from the actual system, the average rate of accuracy of our method is 98.64%, our results are more exactly presented methods.

• Periodical: Applied Mechanics and Materials (Volumes 105-107)
• Pages: 1995-1999
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.105-107.1995
• Online since: September 2011
• Authors: Vinh Du Mai, Duo Qian Miao, Rui Zhi Wang
• Keywords: Image Measuring, License Plate Location, Mathematic Morphology, Ostu Method

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