Hough Transform and Its Application in Vehicle License Plate Tilt Correction

Abstract

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In a vehicle license plate recognition system, tilt vehicle license plate has a bad effect on its character segmentation and recognition. In this paper, tilt models of a plate are analyzed and a approach for number plate tilt correction is presented. Hough Transformation is an effective method to obtain vertical or horizontal angle. Though rotating a correct angle, Tilt vehicle license will be rectified using interpolation a rotation method. Experimental result shows that the method can be implemented easily when dealing with dirty number plates and license plate in variant lighting conditions.