Research project area: Audio over IP Networks

Responsible: Peter Svensson

Abstract: This project deals with QoS related to the transport of audio signals over IP networks, e.g. as associated with a multimedia stream. Specifically, it studies the quality of the sound field as perceived by a receiver/listener and its dependence on application, communication channel, reproduction technique, acoustic environment, and possibly modality interaction with video. The communication channels are provided by IP networks, and their properties depend on available resources and states in these networks. Both one-way audio streaming and interactive multi-way audio applications are studied.

The properties and influence of the transmissions channels over IP networks will be studied in conjunction using live experiments (see other projects) and simulation techniques. To some extent the networks may influence encoding at the audio sources, and the networks may be designed to give differentiated treatment to prioritized audio streams. Acoustic aspects of QoS, that is, the perceived acoustic quality, will be quantified for various applications, network solution methods and network competing traffic situations.

Important problems are:

• metrics for perceived quality of reproduced sound fields
• multimedia sessions over IP networks
• techniques for the recording, encoding, transmission and reproduction of 3D audio, i.e., audio with faithful spatial quality, e.g. for video conferencing
• multiple streams and scalability problems for audio signals
• multiple sources and receivers
• error concealment and graceful degradation of quality for audio signals
• virtual acoustics for use in network communication