Research Article
DevelopmentofANPRFrameworkforPakistaniVehicleNumber
Plates Using Object Detection and OCR
Salma, Maham Saeed, Rauf ur Rahim, Muhammad Gufran Khan , Adil Zulfiqar,
and Muhammad Tahir Bhatti
Department of Electrical Engineering, National University of Computer and Emerging Science,
Islamabad (Chiniot-Faisalabad Campus), Islamabad, Pakistan
Correspondence should be addressed to Muhammad Gufran Khan; m.gufran@nu.edu.pk
Received 12 February 2021; Accepted 27 September 2021; Published 19 October 2021
Academic Editor: Atila Bueno
Copyright © 2021 Salma et al. is is an open access article distributed under the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
e metropolis of the future demands an efficient Automatic Number Plate Recognition (ANPR) system. Since every region has a
distinct number plate format and style, an unconstrained ANPR system is still not available. ere is not much work done on
Pakistani number plates because of the unavailability of the data and heterogeneous plate formations. Addressing this issue, we
have collected a Pakistani vehicle dataset having various plate configurations and developed a novel ANPR framework using the
dataset. e proposed framework localizes the number plate region using the YOLO (You Only Look Once) object detection
model, applies robust preprocessing techniques on the extracted plate region, and finally recognizes the plate label using OCR
(optical character recognition) Tesseract. e obtained mAP score of the YOLOv3 is 94.3% and the YOLOv4 model is 99.5% on
the 0.50 threshold, whereas the average accuracy score of our framework is found to be 73%. For comparison and validation, we
implemented a LeNet Convolutional Neural Network (CNN) architecture which uses the segmented image as an input. e
comparative analysis shows that the proposed ANPR framework comprising the YOLOv4 and OCR Tesseract has good accuracy
and inference time for a wide variation of illumination and style of Pakistani number plates and can be used to develop a real-time
system. e proposed ANPR framework will be helpful for researchers developing ANPR for countries having similar challenging
vehicle number plate formats and styles.
1.Introduction
Vehicle ownership is increasing proportionally with the eco-
nomic growth that makes the management and governance of
the transportation system complicated. Violation of traffic
rules, overspeeding, and car theft are common practices. e
detection and retrieval of number plates from fast-moving
vehicles make it hard to catch and penalize the culprit. e
traffic congestion and unavailability of parking slots lead to the
problem of time, fuel consumption, and air pollution. Till
today, the vehicle number plate is often noted manually, and
human errors in record keeping are unavoidable. Indeed, there
is a need to have an automatic and efficient device for detecting,
collecting, and managing car information.
In the era of the fourth industrial revolution, an Intel-
ligent Transport System (ITS) is a necessity in which the
ability to share information without any human intervention
is possible by the use of Artificial Intelligence (AI) and the
Internet of ings (IoT). e most important subsystem of
an ITS is Automatic Number Plate Recognition (ANPR).
e ANPR system reads the image, preprocesses it, and
recognizes the vehicle number plate characters independent
of human involvement. It helps to identify potential risks,
prevent crime, improve reliability, develop barrier-free in-
frastructure, and provide location information. e Global
Automatic Number Plate Recognition System Market is
forecasted to increase with a ratio of 9.63% from 2017 to
2025 [1].
e studies show that existing ANPR methods are not
viable, and it is hard to find a single efficient approach for
different regions due to the unique format and style of each
region. Several parameters, namely, vehicle pace,
Hindawi
Complexity
Volume 2021, Article ID 5597337, 14 pages
https://doi.org/10.1155/2021/5597337