3D Video: From Capture to Diffusion

Chapter 11

3D Mesh Compression

11.1. Introduction

With technological progress in the domains of digital acquisition, telecommunications and geometric modeling, 3D objects (both static and animated) occupy an increasingly important role. This emerging multimedia content is, for the majority, made up of 3D and 3D+t polygonal meshes, which are generally bulky due to increases in precision and the richness of the data they carry. In parallel, these 3D objects are increasingly used for Internet applications, or as part of online collaborative platforms, where they need to be transmitted rapidly across a network. Thus, the compression of these objects has become an essential scientific concern, involving multiple objectives such as the compact storage of data, interactive time transmission across networks, progressive content visualization and rapid random access.

In this chapter, we begin by considering certain basic points of information theory, the sampling and quantization notions needed to reduce the quantity of data and notions of rate-distortion. We then consider multiresolution analysis. This consists of decomposing a mesh into a series of resolution levels, for example by using wavelet transformations. This method offers an elegant and effective framework for compressing meshes and sequences of meshes, but generally requires the use of a semi-regular mesh, often obtained through an earlier remeshing process. We then present monoresolution coding methods based on highly effective ...