Digital Video Convergence

Internet-based TV seems inevitable because the potential services are compelling, and because the newcomers to broadcasting from the computer industry appear keen to drive it that way. Traditional broadcasters are likely to simulcast on the Net in the next few years, as many radio stations do today. Theoretically, the number of channels is unlimited. So if choice is a competitive factor in TV, the Internet has a clear advantage. Some of the less blinkered in the TV industry are beginning to talk of narrowcasting on the Internet, comparing future services to magazine publishing today with thousands of titles catering for every taste.

The Internet will also make video-on-demand possible at a reasonable cost, giving video companies such as Blockbuster an opportunity to take on movie broadcasters like Sky. On the Internet, even independent film-makers have as much distribution power as the major film studios. By reducing the cost of distribution, the Internet favours the content creator or owner. Anyone can be a broadcaster on the Internet, and many programme producers will attempt to cut out the middle man. At the end of the 1990s it was the music industry that was running scared under the threat of technologies like MP3. Early in the new millennium it will be TV broadcasters.

But where and on what will Internet TV be watched – a television set or a PC? The manner in which the two draw an image on the screen is fundamentally different. A TV interlaces its images, drawing every other line before going back to the starting point to draw the lines in between, while a monitor will use progressive scanning, drawing each line in turn. PC users in the USA are fortunate, since a number of major broadcasters there have come out in support of the progressive format for digital broadcasting. In the UK broadcasters are likely to continue to use the normal 625-line interlace format on DTV for some time yet. For display on the PC, the picture will have to be converted to progressive format, and this conversion will be a task for the PC rather than the digital set-top box.

Notwithstanding these issues, the momentum towards the merging of the television set and PC looks unstoppable, and developments in video compression and low-cost PC technology are starting to throw up an array of hybrid devices. While crude video is already part of Web content, PCs are gaining more TV-like attributes. The cost of cards which put a window of live TV on a PC’s screen has fallen. Thanks to low-cost MPEG-2 decoding chips, DIY receiver cards are becoming available. Many graphics cards are fitted with MPEG encoding facilities as a bonus, so PC users can record TV from air. Software-only solutions are appearing and DVD-Video playback – with either software or hardware decoding – is fast becoming a standard on all but entry level PCs.

In the front room, black boxes are stacking up fast for countless new digital capabilities. Several companies already offer Internet boxes which support email and viewing of specially optimised Web sites on the TV screen. In these cases the TV acts in much the same way as would a monitor on a PC and the boxes act as stripped-down PCs, usually containing a hard disk and a modem for communication with the ISP. Perhaps the best known version of this is Microsoft’s WebTV.

Indeed, Internet access is being added to almost every TV-connected device – DTV receivers, games consoles, and so on – and the latest games consoles now support DVD-Video playback. A new breed of hard disk-based VCRs capable of recording up to 30 hours of video have begun to emerge, giving a taster of what will he possible when recordable DVD-based devices appear later in 2000. Designed to work with standard definition terrestrial broadcasts, as well as digital satellite systems and cable programming services, these so-called PVRs (Personal Video Recorders) enable consumers to play, pause, fast forward or rewind “live” television broadcasts as they are being watched. Not that PVRs have completely killed off the more conventional tape-based VCR – yet. The latest digital VCRs are capable of recording several MPEG-2 streams simultaneously, directly from a digital TV decoder.

This explosion in entertainment devices on the desk and in the front room is bringing about enormous duplication and redundancy, both in computer power and video and audio processing, and that’s surely expensive. This mitigates in favour of household networks. In this model, a household server with a fat pipe onto the Internet will be the entry point for video into the home. This will then be routed across a network (wired or wireless) to appropriate, simple terminals and devices around the home for viewing. Where we are entertained won’t be determined by the technology but by what’s natural or most convenient. The technology will be sufficiently flexible to enable you to just as easily sneak in a snippet of your favourite show while at your desk as read your email whilst stretched out on the sofa.