Automatic Number Plate Recognition System

Abstract

Automatic number plate recognition is a complex mathematical and algorithmic problem. It provides great benefit to many businesses and organizations in a wide variety of applications. Automatic number plate recognition technology is the major part in the proposed security access control system. In this security access control system, initially the number plates of the authorized vehicles are stored in a database. When the vehicle is at the entrance, the number plate of the vehicle is recognized, then compared with the stored data to identify whether the vehicle is authorized or not. At the entrance, the image of the vehicle is captured by the video camera and then a set of video frames are grabbed. After that, three main algorithms are used to recognize the number plate of that particular vehicle. Those are number plate localization, character segmentation and character recognition. First, connected component analysis and aspect ratio of the rectangular area are used to locate the number plate. Then, integral projection functionality is used to segment the characters in the number plate. Finally, the segmented characters are recognized using a back propagation algorithm.