Edge extraction is an usual method in the field of image processing. But it's not enough to exactly describe the detected object only using edge information in the practical applications. So how to restore the binary image according to the direction chain codes is an important problem in image processing field. A binary image can be described by using one or several direction chain codes that record the contour of this binary image. Many methods heve been proposed in the literature

but there still exist the drawbacks such as large computation and inaccurate restoration. In this paper

a new and fast method for restoration of binary image is presented to solve the problems

which is based on the sort of edge points and the chain coding of the boundaries. Experimental results show that this method is computationally faster than the previous methods and does not miss any part of the interior. It's a good restoration method

and already has been used in the practical application.