BBC Research and Development has opened its doors for a demonstration of some of its latest thinking, including developments in interactive television.
The BBC R&D campus at Kingswood Warren in Surrey has been home to many breakthroughs in broadcasting technology, not least in the transition to digital television and the emergence of online and interactive services.
Based in a slightly run-down, rambling neo-gothic manor house to the south of London, every two years Kingswood Warren opens its doors to invited visitors to demonstrate its latest work in progress.
Rather like the home of a mad professor, the rooms always seem reminiscent of a game of Cluedo, the largest being the ‘Cedar Room’ overlooking a croquet lawn on which is parked a helicopter, together with various vehicles used in spectrum planning surveys. Inside, some of the best engineers in the business presented their latest prototypes and inventions. A significant proportion of the projects on show related to interactive television.
Interchange of interactive services
With three different distribution systems to support – satellite, terrestrial and cable – the BBC has been looking at cross-platform authoring technologies for five years. This work is now feeding into the DVB-PCF or Portable Content Format initiative.
PCF is designed to enable the business-to-business interchange of high-level descriptions of interactive services between different content providers and platform operators. Essentially, PCF aims to provide a common language to enable the translation of certain types of interactive service between different platforms.
A first version of the PCF specification is expected to be delivered towards the end of the year.
Archiving interactive television
With interactive television now considered an integral part of the viewer proposition for many digital platforms, there is now a requirement to be able to capture and store interactive services as transmitted, for legal purposes, historical record, operational requirements, or subsequent retransmission.
A prototype system, built entirely from off-the-shelf hardware, allows MPEG-2 transport streams to be captured and replayed, enabling the recreation of an original transmission, even when it spans multiple television channels.
Internet protocol television
The BBC is experimenting with video streaming to deliver certain live television programming to participating internet service providers. Last summer coverage of the Olympics in Athens was demonstrated with 320Kbps streams in RealNetworks format. Experiments are now underway with non-proprietary compression schemes such as MPEG-4 Part 10 AVC H.264.
Traditional unicast web streaming is simply not a scaleable or sustainable solution for live programming, so the BBC is working with a number of internet service providers on a multicast model to deliver a single stream that can be distributed to virtually any number of users. A similar system has been demonstrated to provide a ‘ringmain’ service around BBC premises.
With the advent of personal video recorders, video-on-demand services, and a proliferation of channels, even finding programmes becomes a problem.
The BBC has been a long-time supporter of TV-Anytime, a set of proposed open standards primarily intended to describe programmes to facilitate the development of more sophisticated means of navigation using devices such as personal video recorders.
On show were prototypes of user interfaces from a proof of concept test-bed. However, in order for such systems to become adopted there is still the formidable challenge of enabling broadcasters to add the detailed programme metadata required.
Also on show was a Flash-based facsimile of the Radio Times listings magazine, demonstrated on a rather nice tablet computer, but equally at home on a laptop or desktop. This provided an incredibly faithful replica of a conventional programme guide, which initially seems rather anachronistic, but the layout could be customised to show selected channels, and it would potentially allow a personal video recorder to be programmed directly from a virtual page on screen.
A number of party pieces were also on display, including Piero, a sports graphics system that enables a three-dimensional view of a pitch to be reconstructed from a single camera position. This has recently been used on Match of the Day.
Also on demonstration was an amazing system that allows a virtual 3D object to be tied to a special placeholder in a scene. The MixTV system was recently used to great effect in live coverage of the recent general election results.
Despite the extraordinary level of innovation and invention on show, the very future of BBC R&D is currently under review, and at the very least it seems likely that it will be obliged to leave the rather stately home that it has occupied since 1949. In many ways it epitomises the spirit of the old BBC, an incredibly creative, inventive, and slightly eccentric national institution.