Applying Prewitt Edge Operator Advanced to License Plate Locating

It is well known that license plate locating is a chiefly problem of license plate identify. In order to solve it, we bring forward a method that applying Prewitt edge operator to locate the license plate in this paper. First, we apply Prewitt edge operator advanced to find the pixel of license plate whose color change rapidly and mark it; second, the marked pixel are expanded; last, we judge the fields by the ratio of width and height and so on to clear the noise and locate the license plate. The method has high exact ratio, and can handle the noisy image.