NIST Awards Grant for Video Over DSL Research

Four high-tech companies involved in telecommunications and video have been awarded a $ 4 million grant from the National Institute of Standards and Technology (NIST) to develop a system that provides video services to the U.S. market over the telephone network using asymmetrical Digital Subscriber Lines (DSL). The project is expected to give consumers more choice and lower prices by making DSL more competitive with other broadband services, such as cable and satellite TV.

Sarnoff Corp. Alcatel, SBS Laboratories and Thomson will collaborate on the development of a video system mechanism that enables live or recorded program feeds to be sent to subscribers, and provides a selection of streams to be distributed in real time for decoding and viewing. Each subscriber will be able to view two separate programs on two different TV sets.

To accommodate two video streams on one DSL link, the team plans to compress the video to an average bitrate of 500 kb/s per stream, three times as small as can be achieved with MPEG-2/4. The proposed system is what the team calls "tweening-based compression," a low-bit-rate video compression algorithm that takes its name from the process of "tweening" used in animation. The team also will use an "intelligent video multiplexing" concept, consisting of novel encoding and encapsulation techniques that enable selected video data packets to be discarded without impairing video quality when traffic exceeds transmission limits.