An efficient extension to chain codes for external image representation

A novel contour representation algorithm for binary images which is an extension of the conventional chain code is proposed in this paper. The algorithm exploits the features of the conventional chain code when advantageous, is precise and simple with lesser computational complexity than most of the other standard shape representation algorithms. It uses very low bit-rate compared to the conventional chain code and is more robust to noise. The corresponding reconstruction algorithm is completely reversible to give the lossless reconstruction of the contour. Experimental results on various binary images add to the improved efficiency claim of the proposed contour representation algorithm in terms of visual fidelity and bit-rate