AT_TV: Broadcast Television and Radio Retrieval

This paper reports recent work at AT&T Laboratories Cambridge to develop retrieval systems for broadcast television and radio programmes. Unlike some other systems, it does not rely on manual classification or annotation of the broadcast material; it is indexed automatically from the air. While many digital video library projects focus solely on broadcast news, we have broadened our efforts to produce a continually updated index of all UK terrestrial TV output. We have investigated the use of both video and audio stream analysis, together with closed-caption and speech recognition derived text transcripts, to aid retrieval of whole programmes and of segments within them. We report on the design of two prototypes. The first employs speech recognition to generate transcripts for indexing of radio and television news broadcasts. The second system entitled AT&TV uses closed-caption transcripts where available, to index a much wider range of programmes. A centralised archive is maintained of the past seven days television across four terrestrial channels, thus removing a viewer’s need to select programmes prior to broadcast. The system delivers video-on-demand to clients with broadband access and is in regular use in a lab-wide deployment with around 50 users.