NAVOCEANO Project Proposal from NPAC/Syracuse U.
Enhanced Audio-Video Conferencing Support for the TangoInteractive Collaboratory System
Project POC
David Bernholdt, NPAC/Syracuse University
Email: bernhold@npac.syr.edu
Telephone: 315 443 3857
Fax: 315 443 1973
Project Description
Current audio/video agent (a.k.a. BuenaVista) of the TANGO Interactiveclient has been designed to run over today's Internet. This requirement prompted several design and implementation choices. As BuenaVista is multiplatform, all encoding processes are performed strictly in software. Since video encoding is CPU-intensive, the system has built-in limitations of audio and video quality. These limitations affect the maximal video frame rate (<10 fps), video size (QCIF only), and audio sampling rate and computational complexity of the codec. On the other hand, the system has been designed to be real-time, i.e., to have as low latency as possible, consistent with minimal audio quality requirements.
As public Internet is beefed up by new trunk lines, and as the MSRCs move towards DREN and Internet2, the minimalistic design requirements of the current BuenaVista may appear too restrictive. We hence propose enhancement of the audio/video agent to support higher quality audio and video. Implementation of such software will keep MSRCs abreast of commercial technology developments and prepared to take advantage of the better quality of service available on the new generation of packet networks. In addition, the new tool, supporting a broader range of qualities of audio and video streams, will be positioned to take advantage of the emerging quality of service support and to support adaptive QoS on future integrated services networks.
Currently, audio/video agent supports standard audio and video codecs, such as GSM for audio and H261/H263 for video. The benfit of standard coders is that they are also supported by a growing number of hardware encoders. In particular, H263 hardware encoders are available for both PC and UNIX platforms. Recently, the quality and robustness of the low bitrate hardware video encoders reached the point at which they can be safely deployed in mission critical information systems. Such a deployment is hampared by lack of multi-platform, multiuser, standard compliant videoconferencing software capable of supporting mixed configurations of software and hardwarei-based encoders.
By designing current TANGO Interactive audio/video agent we have demonstrated capability and expertise to implement multiplatform videoconferencing solutions of industrial quality. We propose to take the next step towards high-quality audio/video support for synchronous distance learning and real-time videoconferencing by enhancing TANGO audio/video agent to support hardware-based, standard commodity audio and video encoders.
We have organized this project as a 12 month effort divided in to two phases
Phase 1 Jan 99 – May 99, 5 months, NAVO PET Contract Year 3
Phase 2 Jun 99 – Dec 99, 7 months, NAVO PET Contract Year 4
The Project Deliverables and Budget reflect the two phase nature of this project.
Project Deliverables
The enhancements implemented in this project would result in a desktop videoconferencing system with the following characteristics:
In particular, at the end of phase one (May '99), NPAC will deliver fully functional version of BuenaVista for PC platforms, using Osprey-1000 hardware codecs. This version will support at least 15 frames per second in the CIF format between PC platforms, using at least the H.261 video coder. The version will support H.263 coder as well, although achievement of the 15 fps frame rate is not guaranteed in this format. Current audio coders used by BV will be enhanced by addition of the G.711 or G.722 coders. We will provide code version for both Windows 95/98 and Windows NT operating systems.
The remaining features listed above will be included in the software version delivered in Dec. 1999. This in particular includes RTP support, and mixed software and hardware codecs configuration.
Project Benefits
The enhancements outlined in this proposal will improve the quality of videoconferencing using Tango where appropriate resources (computer systems, network access) are available. This, in turn, will enhance the usefulness and user acceptance of electronic videoconferencing tools for both training and collaboration.
Collaboration
We will make tools available to NAVO PET staff and partners, as they become ready for testing. This will benefit the project by increasing the robustness of the final delivered tools, and provide early access to the tools for interested users.
Budget Justification