Video Does Not Equal Data - How to Transport Pictures

The convergence of telecommunications, information processing and multimedia is of strategic importance worldwide and will enable both businesses and citizens to have access to extensive on-line communication, security and entertainment services. Future services will need to be delivered at a range of bit rates, dependent on network and channel characteristics, platform type, application and material content. End to end provision of multimedia information across network components of varying capability and performance will therefore impose the need for coding regimes which are scalable and inherently robust to loss and error, while maintaining data security. This lecture will focus on the delivery of real time video. It will emphasise the differences between compressed video and other forms of data, explaining why errors occur, how they propagate and will describe a range of techniques for mitigating their effects. These will include various forms of redundancy, video adaptive mode selection, the use of feedback, cross layer mapping and error concealment. The above issues will be explored in the context of emerging wireless IP communication networks and video coding systems.