On DPCM and its variation applied to geometry compression

There has been increasing interest in 3D geometry compression. One reason is that the insufficient bandwidth between the graphics pipeline and the main memory is not able to handle the huge amount of 3D graphics data transferred between these two components. A variation of open-loop linear predictive quantization (OLPQ), a widely used but not well-studied coding technique, was proposed to become the geometry coding technique of MPEG4 3D model coding (3DMC). We compare the performance of OLPQ with the well-understood differential pulse code modulation (DPCM). Our results show that DPCM does not outperform OLPQ in the coding of vertex coordinates of 3D objects in the rate-distortion sense. Such results together with the lower complexity of OLPQ makes OLPQ a better geometry coding technique than DPCM.