Title :
Method of License Plate Location Based on Corner Feature
Author :
Qin, Zhong ; Shi, Shengli ; Xu, Jianmin ; Fu, Hui
Author_Institution :
Coll. of Traffic & Commun., Southern China Univ. of Technol., Guangzhou
Abstract :
License plate location (LPL) plays an important role in the license plate recognition (LPR). The license plate characters contain abundant corners which distribute intensively and regularly. Accord to the feature, a novel method to locate the license plate accurately and fast is proposed in this paper. The method is dived into three steps which are corners detection, finding out candidate license plates and locating the license plate accurately. In the course of locating license plate, three thresholds are used. First, the reasonable threshold is used to eliminate a great number of non-corner pixels to speedup corner-detections. Second, a big threshold is selected with a slid window to find out candidates. Finally, the region of candidate license plates are expanded, all the corners in it were stand out with a smaller threshold, and the license plate is located accurately using clustering analyses. Experiments have been conducted, 1200 license plate images are tested, the accuracy is 98.42% and the average consuming time is 20ms
Keywords :
automated highways; edge detection; feature extraction; object recognition; pattern clustering; clustering analysis; corner detection; corner feature; intelligence traffic systems; license plate characters; license plate location; license plate recognition; noncorner pixels; slid window; Character recognition; Image edge detection; Image segmentation; Intelligent systems; Intelligent vehicles; Licenses; Neural networks; Space technology; Space vehicles; Vehicle detection; Corner Detection; License Plate Location; License Plate Recognition; intelligence traffic systems;
Conference_Titel :
Intelligent Control and Automation, 2006. WCICA 2006. The Sixth World Congress on
Conference_Location :
Dalian
Print_ISBN :
1-4244-0332-4
DOI :
10.1109/WCICA.2006.1713668