Triangular matrix-based lossless compression algorithm for 3D mesh connectivity

Three-dimensional mesh compression is vital to support advances in many scenarios, such as 3D web-based applications. Existing 3D mesh methods usually require complex data structures and time-consuming processing. Given a mesh represented by its vertices and triangular faces, we present a novel, fast, and straightforward encoding algorithm. Our method encodes the mesh connectivity data based on an upper triangular matrix which is easily recovered by its underlying decoding process. Our technique encodes the mesh edges in linear time without losing any face in the process. Results show that our method provides a connectivity compression rate of 55.29 and an average total compression rate of 27.09. Furthermore, our approach achieves, on average, a similar compressing rate of state-of-the-art algorithms, such as OpenCTM, which considers geometry and connectivity, while our approach considers only their connectivity.