Watermarking Graphical Objects

Watermarking has been used for protecting the copyright information in various data such as audio signals, images and video. Copyright protection of graphical objects and models is important for protecting author rights in animation, multimedia, computer-aided design (CAD), virtual reality, medical imaging, etc. Watermarking techniques in 3D graphical objects are facing new challenges because of the specific nature of the information available in 3D graphics. In this paper we suggest a blind watermarking algorithm for 3D models and objects. A string of bits is embedded in the geometrical structure of the graphical object by changing the locations of certain vertices. The criterion employed for selecting the vertices ensures a minimal visibility of the distortion in the watermarked object. The proposed 3D graphical object algorithm is applied in various 3D graphical models including characters and industrial objects.