In order to recognize vehicle license numbers in real time, a CCD (charge-coupled device) camera with electronic shutter and a hierarchical computer system with a general-purpose microprocessor and pipelined image processors have been developed. Much quicker extraction of the vehicle-license plate on the front-view image is realized by optimization of parameters using Taguchi's method. Distinct images outdoors can be obtained using a suitable control of the lens-diaphragm and continuous lighting via floodlight equipment. The results of field tests show that recognition rates of about 90% in the daytime and about 65% at night were attained. The processing time per vehicle is about 150 ms on average.
Development of vehicle-license number recognition system using real-time image processing and its application to travel-time measurement
Entwicklung eines Systems zur Erkennung von Fahrzeuggenehmigungen durch Echtzeit-Bildverarbeitung und die Anwendung für Reisezeitmessungen
1991
7 Seiten, 5 Quellen
Conference paper
English
The Research of Travel Time Estimation Based on Vehicle License Plate Auto Recognition System
Trans Tech Publications | 2014
|Vehicle License Number Recognition System Using Neural Network
British Library Conference Proceedings | 1995
|