Experiment of Geometrically Invariant and Unneeded Synchronism Watermarking Using Winding Number

This paper presents a new scheme and algorithm for robust watermarking against general geometric distortions, such as rotation, scale, and translation. Some previous methods need synchronism to robust for geometric distortion between embedded and detected locations. However, synchronism requires extensive calculations cost and does not resist radical distortions. We propose a watermarking scheme using a winding number, which is a topological invariant that is not changed by geometric distortions. Winding number is extracted figure like a circle; therefore this does not require synchronism in our scheme. This paper shows one of the algorithms to implement our scheme, and evaluates this implementation.