MPEG-4 Part 25: A graphics compression framework for XML-based scene graph formats

This paper introduces a new model for applying 3D graphics compression to arbitrary scene graphs, recently adopted by MPEG in Part 25 of the MPEG-4 standard. The goal of the model is twofold: to liberate the powerful MPEG compression techniques from the scene graph representation based on BIFS and to position the compression as a transparent layer in the 3D graphics chain, thus making it easy to integrate in third party authoring tools or end-user applications. In addition, intrinsic features of the compression tools such as progressive decoding or streaming are preserved. Currently implemented on top of COLLAborative Design Activity (COLLADA) and eXtensible 3D (X3D), the proposed model will leverage the deployment of MPEG-4 compression for 3D graphics. The software implementation, publicly available under ISO license, is introduced and reports and analyses of the compression results on large database are outlined in the document.