A Novel Robust 3D Mesh Watermarking Based On The Visual System

In recent years, three-dimensional model is being widely applied, with the rapid development of the computer graphics and the popularization of the Internet. Three-dimensional model has become an important object of intellectual property protection. In this way, Three-dimensional digital watermarking has been widely researched as an effective solution for copyright protection and authentication of three-dimensional models. The information embedded into the model is not visible to the user, it also does not affect the function of the model, it could be easily detected from the model and used for copyright protection and authentication.The first watermarking method of three-dimensional models was presented by Ohbuchi in 1997,it provided a new method for the research of digital watermarking. Over the last decennium, three-dimensional digital watermarking has resulted in the following areas of research: Watermark embedding and extraction, the watermark attacks, watermark assessment etc. According the domain the watermark was embedded, three-dimensional digital watermarking can be divided into two parts: transform domain watermarking and spatial domain watermarking. In accordance with the different application areas, watermarking can be classified into two parts: the robustness watermarking for Copyright protection and the fragile watermarking. Watermarking can also be divided into two parts: private watermarking and public watermarking. Watermark attack methods have the following: robustness attacks, interpretation attacks, legal attacks. Watermark performance assessment has the following categories: Receiver Operation Characteristic curve(ROC),Bit Error Rates(BER),Model Shape Variable, Signal-to-Noise Ratio(SNR) and Peak-Signal-to-Noise Ratio(PSNR) etc. Chapter 2 of this article reviews the current watermarking techniques for three-dimensional models.This study focused on the relationship between the watermark and the visual characteristics of the model. Color, shading, texture, or other attributes may be easily changed or removed. Due to the specificity of three-dimensional model, vertex coordinates are the most suitable features to be used for watermarking graphical objects.The main objective of 3D mesh watermarking is to maximize the watermark strength while minimizing the visual distortion. The regions having better visual mask ability in the model could meet the needs of three-dimensional watermarking very well.In this paper, we propose a novel robust 3D watermarking scheme based on the analysis of curvature and fluctuation of curvature, which used to evaluate the visual distortion of the model. We analyze the region's mean curvature and fluctuation of curvature, and then choose the appropriate regions with high visual masking degree, in order to embed the watermark by using the Interpolation Algorithm We spend less visual distortion to embedding higher watermark strength. Experimental results proved that the algorithm was invisible and robust against variety attacks well, such as rotation, scaling, cropping, noise and smooth.