Decorrelation Techniques for Geometry Coding of 3d Mesh

There exists a lot of redundancy in 3D meshes that can be exploited by Blind Source Separation (BSS) and Independent Component Analysis (ICA) for the goal of mesh compression. The 3D meshes geometry is spatially correlated on each direction in the Cartesian coordinate system. In the context of mesh compression with BSS algorithm, it is proposed to take the correlated geometry of 3D mesh as observations and decorrelated geometry as sources corresponding at largest energy. The geometry decorrelation is obtained by using EVD, SOBI, and Karhunen-Loève transform. In Karhunen-Loève transform case, to reduce the transform matrix dimension, the correlated geometry is divided into blocks and then by averaging the covariance matrices of each block, a global covariance matrix is performed. The transform matrix represents the bitstream of compressed file. Its elements are quantized and encoded using arithmetic coding, providing effective compression.