Research Projects
Adaptive Error Measurement, Concealment, and Repair for IP Streaming Video
Internet Protocol Television (IPTV) systems are a rapidly growing converged network service. These systems replace the traditional “set-top box”, receiving broadcast or cable television, with a networked IP-centric device, to which video is streamed live or on demand. The user experience initially follows that of traditional television, but it is expected that additional interactive services will be offered over time, as the potential of the underlying converged network architecture is exploited. Key to this, however, is ensuring the television service provided matches – or exceeds – that of traditional broadcast television. Converged networks suffer from different problems than do pure data networks and dedicated real-time transmission networks, so there is a need for new algorithms and protocol mechanisms to monitor reception quality and diagnose network problems. This project aims to develop such new algorithms and protocols.
Specifically, the key areas we will address are algorithms for correlation and analysis of reception quality reports, methods of efficiently reporting reception quality, and media stream repair techniques. Building on existing standards, we will develop both per- and cross-stream analysis algorithms to locate and diagnose problems with media delivery, design new reception quality report transport, summarization, and aggregation protocols, and use these to improve quality and manageability of IPTV systems.
This project is joint work with Prof. Dr. Jörg Ott at the Helsinki University of Technology. Funding is provided by Cisco Systems.
UltraGrid - A High Definition Collaboratory
The goals of the NSF-funded UltraGrid project are to enhance the state of the art in high quality, large scale, telepresence systems and to enable flexible and ad-hoc remote collaboration.
The UltraGrid video conferencing system was the first to support high definition interactive video conferencing with low latency. Using its highest quality mode, UltraGrid supports uncompressed high definition video (720p/60) at approximately 1.2 Gbps; it also supports standard definition video formats and a range of compression algorithms. When used with the AccessGrid venue server infrastructure and audio service, UltraGrid forms a complete high definition video conferencing system.
UltraGrid is primarily intended as a platform for research into real-time network transport protocols and novel video coding algorithms. Key innovations include integration with custom IPsec acceleration hardware to provide secure interactive conferencing at gigabit rates, and the incorporation of TCP-Friendly Rate Control to adapt the video quality to variations in network capacity.
Main website: http://ultragrid.dcs.gla.ac.uk/