Watermarking for 3-D Polygon Mesh Using Mean Curvature Feature

Copyright protection of 3-D objects are also important for protecting author rights in animation, multimedia, computer aided design (CAD), virtual reality, medical imaging etc. Especially in the grown up market of video-games, there is demand for a watermarking technique for 3-D-objects. In this paper, we propose a robust watermarking algorithm having less perceivable distortion for 3-D polygon mesh objects based on geometrical properties. The selection of vertices for watermark embedding is based on perceivable distortion. The perceivable distortion is defined as the distortion observed by human observers. The selection of vertices for watermark embedding is an important factor for perceivable distortion as watermark embedding in deeper surface has less perceivable distortion in comparison to watermark embedding in flat or peak surfaces. In the proposed algorithm, we exploit this observation for selection of vertices for watermark embedding. The watermark is embedded by repositioning the selected vertices from their original positions.