A Method Of Car Number Plate Extraction Using Two Kinds Of Modified Hough Transformations

In this paper, we propose a method of extracting the regions of car number plates using two kinds of modified Hough transformations. One is a parameter restricted Hough transformation(PRH) and the other is a hierarchical parameter restricted Hough transformation(HPRH). The PRH algorithm, in which the range of the parameter plane is restricted, reduces the computation time and the storage capacity than the usual Hough transformation. The HPRH algorithm uses a hierarchical structure of image, and it also includes the PRH algorithm. The hierarchical structure reduces the picture points to be processed.