Academic Journals Database
Disseminating quality controlled scientific knowledge

A Design Flow for Robust License Plate Localization and Recognition in Complex Scenes

Author(s): Jafar Saniie | Erdal Oruklu | Dhawal Wazalwar

Journal: Advances in Molecular Imaging
ISSN 2161-6728

Volume: 02;
Issue: 01;
Start page: 13;
Date: 2012;
Original page

Keywords: License Plate Localization | Character Recognition | Reflection Symmetry Coefficient | Artificial Neural Network

In this paper, we present a new design flow for robust license plate localization and recognition. The algorithm consists of three stages: 1) license plate localization; 2) character segmentation; and 3) feature extraction and character recognition. The algorithm uses Mexican hat operator for edge detection and Euler number of a binary image for identifying the license plate region. A pre-processing step using median filter and contrast enhancement is employed to improve the character segmentation performance in case of low resolution and blur images. A unique feature vector comprised of region properties, projection data and reflection symmetry coefficient has been proposed. Back propagation artificial neural network classifier has been used to train and test the neural network based on the extracted feature. A thorough testing of algorithm is performed on a database with varying test cases in terms of illumination and different plate conditions. Practical considerations like existence of another text block in an image, presence of dirt or shadow on or near license plate region, license plate with rows of characters and sensitivity to license plate dimensions have been addressed. The results are encouraging with success rate of 98.10% for license plate localization and 97.05% for character recognition.

Tango Rapperswil
Tango Rapperswil

     Affiliate Program