Redundancy in 3D polygon models and its application to digital signature

This paper introduces new watermarking schemes for 3D polygon models. The schemes presented here use just the redundancy in model description, hence essential model data such as vertex coordinates and topology are left intact. Proposed Full Permutation Scheme (FPS) and Partial Permutation Scheme (PPS) embed information by permuting the order of vertices or faces, and Polygon Vertex Rotation scheme (PVR) embeds information by rotating the vertices of faces. The digital signature procedure for verification purposes is also presented, which works in cooperation with popular public-key cryptography. A modified PVR scheme (Packet PVR) is then proposed for more robust signature. Evaluation results show that our schemes can embed 0.2% (by Packet PVR) - 2.8% (by FPS) of information compared to the original model file size. Our methods are orthogonal and complementary to the preceding methods that use geometrical and topological domain.