An Approach of Locating Korean Vehicle License
Plate Based on Mathematical Morphology and
Geometrical Features
Ihsan Ullah
1
1
Division of Computer Science and Engineering,
Chonbuk National University,
Jeonju 561-756, South Korea
Ihsanullah736@gmail.com
Hyo Jong Lee
1, 2,*
1
Division of Computer Science and Engineering,
2
CAIIT,
*Corresponding author
Chonbuk National University,
Jeonju 561-756, South Korea
hlee@chonbuk.ac.kr
Abstract— In a vehicle license plate identification system,
plate region detection is the crucial step before the ultimate
recognition. In most of the traffic-related applications such as
searching of stolen vehicles, road traffic monitoring, airport
gate monitoring, speed checking and parking access control.
This paper is focused on license plate detection, license plate
detection in this paper is based on mathematical morphology
and considers features like license plate width, height, ratio,
and angle. The advantage of the proposed system is that it
works for all types of license plates which differ in size and
shapes. The proposed system archived promising results.
Keywords—license plate detection; morphology; lp
localization; lpd
I. INTRODUCTION
Vehicles are a necessary part of our existing life. With
the fast improvement of Intelligence transportation system,
automatic identification of vehicles has played a vital role in
many applications during the past two decades for examples,
the identification system can be applied to management of
parking services [1], controlling traffic flow[2], access-
control systems, automatic toll collection[3], traffic analysis,
vehicle tracking system[4], and [5] identification of stolen
vehicle can deliver important information to police for
searching the suspected vehicles and so on.
Conventionally, license plates are used for identification
of every vehicle. License Plate Recognition (LPR) is the
process of automatically locating and extracting license plate
information. In the LPR system, license plate detection is the
most critical step. It is exceptionally difficult to detect
license plate from a cluttered background efficiently because
of the varying brightness, perspective distortion, interference
characters, etc. Most of the previous license plate detection
algorithms are restricted to certain working conditions, such
as fixed backgrounds, known the color, or fixed size of the
license plates[6-9]. Therefore, detecting license plate under
various complex environments is still a challenging problem.
In recent years, LPR has become popular due to its
practical significance in image processing applications.
Numerous improvements are suggested in the literature [10,
11] which present effective and precise systems to detect
license plate and recognize the numbers and character on the
license plate in complex scenes which directly affects the
system’s overall performance. A large number of researches
has been carried out for the development of this technology
recently, and many techniques have been proposed, such as
the methods base on edge extraction [12], Hough transform
[13], color feature [14], and histogram analysis [15]. But
most previous works have in some way limited their working
environments, such as limiting them to indoor scenes, fixed
background, fixed brightness, prescribed driveways or
limited vehicle speeds.
License plate numbers uniquely identify a specific
vehicle which varies in shape and formats, because every
country has particular license plate layout which differs in
their sizes and colors. So there is a requisite for the
authorities to develop such LPR system which is suitable for
the vehicle License Plate different format. In general, the
LPR system has the following parts: the obtainment of the
input image, the image preprocessing, detection of the
license plate, segmentation and the character recognition
[16]. The basic block diagram of the system is shown in
Figure 1.
Fig. 1. The basic block diagram of the License Plate
Recognition (LPR) System.
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
832
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
832
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836
2016 International Conference on Computational Science and Computational Intelligence
978-1-5090-5510-4/16 $31.00 © 2016 IEEE
DOI 10.1109/CSCI.2016.161
836