A new digital watermarking scheme for 3D triangular mesh models

This paper proposes a new watermarking scheme for three-dimensional (3D) triangular mesh models. In this new scheme, feature points from the rapid changing regions are used to uniquely partition a 3D mesh model into Voronoi patches. Each Voronoi patch is then projected to a reference square plane and the corresponded range image is generated. By employing the existing two-dimensional (2D) image watermarking algorithms, watermark information is embedded into the transform domain of each range image. The watermarked 3D mesh model is obtained by perturbing the vertexes of each patch according to its watermarked range image. In order to make the watermarking scheme robust against various forms of attacks while preserving the perceptibility of the model, the length of the watermark information, the number of the feature points and the embedding strength of the watermark are made adaptive with respect to the geometry complexity of the 3D mesh models. Experimental results show that the proposed watermarking scheme has good imperceptibility and performs well under common 3D watermarking attacks such as mesh simplification, adding noise and cropping.