A new contour tracing automaton in binary image

A new contour tracing automaton for four-connected binary images is presented in this paper. The algorithm adopts a unique contour labeling method to trace contour of image. While traversing the image, the inner contour and outer contour can be distinguished. Connectivity information also can be preserved simultaneously. Furthermore, it is capable of generating the three traditional types of chain code. Experiments after prove that the new algorithm increases the coding efficiency for binary image.