Adaptive filtering of MPEG system streams in IP networks

Congestion and large differences in available link bandwidth create challenges for the design of applications that want to deliver high quality video over the Internet. We present an efficient adaptive filter for MPEG System streams that can be placed in the network (e.g., as an active service). This filter adjusts the bandwidth demands of an MPEG System stream to the available bandwidth without transcoding while maintaining synchronization between the streams embedded in the MPEG System. The filter is network-friendly: it is fair with respect to other (TCP) competing streams and it avoids generating bursty traffic. This paper presents the system architecture and an evaluation of our implementation in three different operating environments: a networking testbed in a laboratory environment, a home-user scenario (DSL line with 640Kbit/s), and a wide area network covering the Atlantic (server in Europe, client in the US). Moreover we examine the network-friendliness of the adaptation protocol and the relationship between the quality of the received continuous media and the protocol's aggressiveness. Our architecture is based on efficient MPEG System filtering to achieve high-quality video over best-effort network

Adaptive filtering of MPEG system streams in IP networks

ISSN:1380-7501ISSN:1573-772

MPEG System Streams in Best-Effort Networks

The MPEG format is widely used and therefore an attractive vehicle for the distribution of video and audio material over the Internet. However, the hierarchical structure of MPEG systems complicates the task of delivering continuous, synchronized streams of video and audio in a best-effort environment (today's Internet). If the network throws away packets on encountering congestion, the video and audio stream may loose synchronization for a number of frames. Therefore, adapting the resource demands of an MPEG system must be done by an entity that is knowledgeable of the MPEG system structure: an MPEG system filter. This paper describes the integration of such an MPEG system filter into a network. Our experience to date indicates that mid-range PCs can host such a filter, and that the filter succeeds in adapting the resource requirements of an MPEG system in response to changes in the network load