Geometry-based Point Cloud Compression

In October 2020, MPEG completed development of its ISO/IEC 23090-9 Geometry-based Point Cloud Compression (G‑PCC) standard. G‑PCC addresses lossless and lossy coding of time-varying 3D point clouds with associated attributes such as colour and material properties. This technology is particularly suitable for sparse point clouds. ISO/IEC 23090-5 Video-based Point Cloud Compression (V‑PCC), which was completed in July 2020, addresses the same problem but for dense point clouds, by projecting the (typically dense) 3D point clouds onto planes, and then processing the resulting sequences of 2D images using video compression techniques. The generalized approach of G-PCC, where the 3D geometry is directly coded to exploit any redundancy in the point cloud itself, is complementary to V-PCC and particularly useful for sparse point clouds representing large environments.

Point clouds are typically represented by extremely large amounts of data, which is a significant barrier to mass market applications. However, the relative ease of capturing and rendering spatial information compared to other volumetric video representations makes point clouds increasingly popular for displaying immersive volumetric data. The current draft reference software implementation of a lossless, intra-frame G‑PCC encoder provides a compression ratio of up to 10:1 and lossy coding of acceptable quality for a variety of applications with a ratio of up to 35:1.

By providing high immersion at currently available bit rates, the G‑PCC standard will enable various applications such as 3D mapping, indoor navigation, autonomous driving, advanced augmented reality (AR) with environmental mapping, and cultural heritage.