Video Requirements for Web-based Virtual Environments Using Extensible

This presentation from members of the Web3D Consortium was given at the
"W3C Video on the Web Workshop", held 12-13 December 2007, in San Jose,
California, USA and Brussels, Belgium. Real-time interactive 3D graphics
and virtual environments typically include a variety of multimedia
capabilities, including video. The Extensible 3D (X3D) Graphics is an
ISO standard produced by the Web3D Consortium that defines 3D scenes
using a scene-graph approach. Multiple X3D file formats and language
encodings are available, with a primary emphasis on XML for maximum
interoperability with the Web architecture. A large number of functional
capabilities are needed and projected for the use of video together
with Web-based virtual environments. This paper examines numerous
functional requirements for the integrated use of Web-compatible video
with 3D. Three areas of interest are identified: video usage within X3D
scenes, linking video external to X3D scenes, and generation of 3D
geometry from video. Extensible 3D (X3D) is a Web-based standard for
3D graphics, enabling real-time communication using animation, user
interaction and networking. The point paper lists current and expected
requirements, primarily divisible into usage of video within X3D graphics
scenes, linkage to video in web-based applications external to X3D
graphics scenes, and generation of 3D geometric content from spatially
annotated video inputs. Royalty-free video capabilities are critical
important to achieve essential requirements for interoperability and
performance. Standards-based X3D requirements also appear to be
representative of the needs presented by alternative proprietary
multiuser virtual environments. X3D capabilities are proposed,
implemented, evaluated and approved by members of the nonprofit Web3D
Consortium. X3D is an open, royalty-free standard that is rigorously
defined, published online, and ratified by the International Organization
for Standards (ISO). Multiple commercial and open-source implementations
are available.