It is well known that locating vehicle license plate is a very difficult problem in the fields of image segmentation and ITS(Intelligent Transprotation System).At the present time

the study of vehicle license plate locating mainly focuses on gray images so that the result is affected easily by the presence of shadows and illumination.In this paper

a new color edge detector ColorPrewitt and a new approach of vehicle license plate locating ColorLP are presented

which fully exploit color information and other features of vehicle license plate.ColorPrewitt not only is simple

but also has superiority over traditional color edge detectors in dealing with color vehicle license plate images because it doesn't just simply operate on the individual three channels of color space.It shows that the license plate edges detected using ColorPrewitt are clear

integrated and easy to be separated form the background.ColorLP combines ColorPrewitt and region growing image segmentation technology with high locating ratio and good generality

which is applicable to locate license plates in cases of various backgrounds

positions and illumination.