Optimasi Metode Support Vector Machine dengan Discrete Wavelet Transform Untuk Pengenalan Karakter Plat Nomor Kendaraan

Pengenalan karakter plat nomor kendaraan memiliki peran penting untuk tujuan identifikasi secara resmi, penerapanya telah banyak dilakukan untuk identifikasi otomatis seperti pada tol elektronik, tempat parkir, dsb. Penelitian berkaitan dengan pengenalan karakter setidaknya memiliki fase-fase seperti segmentasi, fitur extraksi dan klasifikasi dimana tiap fase memiliki proses yang rumit. Keberhasilan dalam proses pengenalan karakter sangat tergantung dalam proses fitur ekstraksi, Sehingga pemilihan metode fitur ekstraksi yang dapat mengekstrak fitur-fitur yang relevan perlu dilakukan agar tingkat akurasi sistem pengenalan karakter dapat ditingkatkan. discrete wavelet transform telah banyak digunakan sebagai metode untuk ekstraksi fitur, metode ini melakukan ekstraksi dengan melakukan dekomposisi pada  ruang vektor ke dalam ruang vektor bersarang dengan resolusi yang berbeda. Dalam penelitian ini metode discrete wavelet transform dikombinasikan dengan support vector machine untuk meningkatkan akurasi pengenalan karakter. Penelitian dilakukan dengan mengukur tingkat akurasi dari 100 citra plat nomor, dengan penambahan metode discrete wavelet transform dan support vector machine tingkat akurasi klasifikasi mencapai 92% yang artinya  mendapatkan peningkatan akurasi sebesar 8% dibanding klasifikasi menggunakan SVM standar

Character segmentation for license plate recognition by K-means algorithm

In this paper an improved K-means algorithm is presented to cut character out of the license plate images. Although there are many existing commercial LPR systems, with poor illumination conditions and moving vehicle the accuracy impaired. After examination and comparison of different image segmentation approaches, the K-means algorithm based method gave better image segmentation results. The K-means algorithm was modified by introducing automatic cluster number determination by filtering SIFT key points. After modification it efficiently detects the local maxima that represent different clusters in the image. The process is successful by getting a clean license plate image. While testing by the OCR software, the experimental results show a high accuracy of image segmentation and significantly higher recognition rate. The recognition rate increased from about 86.6% before our proposed process to about 94.03% after all unwanted non-character areas are removed. Hence, the overall recognition accuracy of LPR was improved. © 2011 Springer-Verlag

Detection and Recognition of License Plates by Convolutional Neural Networks

The current advancements in machine intelligence have expedited the process of recognizing vehicles and other objects on the roads. The License Plate Recognition system (LPR) is an open challenge for many researchers to develop a reliable and accurate system for automatic license plate recognition. Several methods including Deep Learning techniques have been proposed recently for LPR, yet those methods are limited to specific regions or privately collected datasets. In this thesis, we propose an end-to-end Deep Convolutional Neural Network system for license plate recognition that is not limited to a specific region or country. We apply a modified version of YOLO v2 to first recognize the vehicle and then localize the license plate. Moreover, through the convolutional procedures, we improve an Optical Character Recognition network (OCR-Net) to recognize the license plate numbers and letters. Our method performs well for different vehicle types such as sedans, SUVs, buses, motorbikes, and trucks. The system works reliably on images of the front and rear views of the vehicle, and it also overcomes tilted or distorted license plate images and performs adequately under various illumination conditions, and noisy backgrounds. Several experiments have been carried out on various types of images from privately collected and publicly available datasets including OPEN-ALPR (BR, EU, US) which consists of 115 Brazilian, 108 European, and 222 North American images, CENPARMI includes 440 from Chinese, US, and different provinces of Canada and UFPR-ALPR includes 4500 Brazilian license plate images; images of those datasets have several challenges: i.e. single to multiple vehicles in an image, license plates of different countries, vehicles at different distances, and images taken by several types of cameras including cellphone cameras. Our experimental results show that the proposed system achieves 98.04% accuracy on average for OPEN-ALPR dataset, 88.5% for the more challenging CENPARMI dataset and 97.42% for UFPR-ALPR dataset respectively, outperforming the state-of-the-art commercial and academics