The Moving Picture Experts Group

What is Part 16, Animation Framework eXtension (AFX)?


The MPEG‑4 Animation Framework eXtension (AFX) —ISO/IEC 14496‑16— contains a set of 3D tools for interactive 3D content operating at the geometry, modeling and biomechanical level and encompassing existing tools previously defined in MPEG‑4 specification. The tools available in AFX and related illustrations are summarized in Figure 1.In order to animate objects over time, AFX defines the following tools: interpolator compression, compressed Bone-Based Animation stream, OctreeImage and pointTexture compression stream and precise control of animation path and timeline.Why use AFX tools in 3D applications? AFX offers, for the first time, a unified standardized framework including a rich set of 3D tools, most of them already well-supported in the industry. Furthermore, advanced features such as compression, streaming, and seamless integration with other audiovisual media, allow building high quality creative cross media applications.AFX tools are suitable for 3D video games, interactive 3D mobile services, animation movies, distributed/collaborative virtual environments, entertainment and cultural applications, e-education… For example, in a 3D first person shooter game, the technical challenges to overcome are: smooth graphics representation, innovative user interface, networked gaming environment, cross platform terminals, mobility, high quality animated 3D contents, smart/behavioral virtual characters. In emerging interactive television show including audiovisual contents and animated emotional characters, temporal synchronization and spatial composition mechanisms are required. All these features are directly provided by AFX and already available tools in MPEG‑4 specifications.