Data embedding algorithms for geometrical and non-geometrical targets in three-dimensional polygonal models

Three-dimensional (3D) graphics is about to become a full-fledged multimedia data type, prompted by the increasing popularity of virtual reality modeling language (VRML) [15] and imminent standardization of MPEG-4 [16]. This paper presents several algorithms for embedding data in triangular meshes, arguably the most important component in both VRML and MPEG4 in defining arbitrary shapes. A topology-modifying algorithm described in this paper embeds bit string in connectivity of triangles, while another algorithm cuts out patterns from a mesh. Yet another algorithm modifies texture coordinate, a non-geometrical quantity, for embedding. Watermarks embedded in 3D graphics contents could be used as a tool in managing intellectual property and other issues associated with these contents. (C) 1998 Elsevier Science B.V. All rights reserved.