While many digital video library projects focus on broadcast news, we have concentrated our efforts on large-scale indexing of general TV output to produce a scalable and usable system. 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. Our initial system used speech recognition to generate transcripts for indexing of radio and television news broadcasts. The current system uses closed-caption transcripts where available, to index a much wider range of television programmes. A centralised archive is maintained of the past seven days television across the four main UK terrestrial channels, thus removing a viewer's need to select programmes prior to broadcast.
Users can simply type in queries and watch any matching programmes or parts thereof.
In conjunction with the current system, we have also implemented a simple user interest profile system. We also use Local Context Analysis of the archived programme transcripts to provide an intelligent query-expansion recommendation facility, allowing users to redefine their interests to make the retrieved programmes more suitable. For comments, suggestions and further information please contact us .