Abstract: We present a digital watermarking algorithm for 3D model which is based on encrypted holographic digital watermarking algorithm to protect the embedded watermark information (such as a specific identity of the copyright information, etc.) and to improve the security and robustness of the digital watermark information. Firstly, the watermark image is processed by the double random phase modulation to get the hologram watermark which makes a high security. Then in the embedding procedures, affine invariant preprocessing is used for 3D models. We calculate the distance of each vertex to center of gravity of the 3D model which is noted as r, and take it as the watermark embedding element to embed the watermark. The experimental results show that the algorithm had the good performance of the watermark robustness to attacks such as noise addition, model simplification, model cropping, and affine attacks. This algorithm can be widely used for digital copyright protection and other aspects of identity hidden.

Keywords: Information optics; Holographic algorithm; 3D model; Digital watermarking; Affine invariant; Data confidentiality.