Watermarking for 3D polygonal meshes using normal vector distributions of each patch

We proposed a watermarking for 3D polygonal meshes using normal vector distribution of each patch. The distribution of norm vector for 3D polygonal mesh is a consistent factor to be robust against various attacks such as af£ne transform and mesh connectivity altering. Therefore, the proposed algorithm embedded watermark into these consistent normal vectors and equal watermark bit was embedded into each patch of subdivided mesh to have robustness against the partial geometric deformation. Experiment results exhibited the proposed algorithm is robust by extracting watermark bit for various attacked models.