A vehicle license plate detection method using region and edge based methods

In this paper, a license plate detection system is implemented. For this purpose, we improve the contrast at possible locations where there might be a license plate, we propose a filtering method called ''region-based'' in order to smooth the uniform and background areas of an image, we apply the Sobel operator and morphological filtering to extract the vertical edges and the candidate regions respectively, and finally, we segment the plate region by considering some geometrical features. In fact the novelty and the strength of our license plate detection system is in applying the region-based filtering that decreases the run time and increases the accuracy in the two final stages: morphological filtering and using the geometrical features. The experimental results show that our proposed method achieves appropriate performance in different scenarios. We should mention that our system is reliable because the accuracy is above 92% in average for different scenarios and it is also practical because of the low computational cost.