Four-strong team builds digital TV revolution

Few consumer technologies begin life in the garage these days. It was once traditional; not now. 

The perception of modern gadgetry is one of immensely complex mixtures of densely integrated electronics and massively involved software, built by large teams of well-funded engineers within even larger companies.

It ain't necessarily so. In mid-March, ZDNet UK took a train to the semi-rural idyll of Ascot and a modest yet rambling building inhabited by a four-person family team that sees no reason why they can't do it all themselves.

That team is led by techno-patriarch Richard Ludlam, whose boyhood passion for radio and electronics led him to set up a TV repair business-cum-design house in the late 1960s. Senior researcher is Kate Ludlam, and the software and hardware design is done by sons Dominic and Christian Ludlam.

Dominic Ludlam: OS, video decoder, user interface, and remote monitoring expert at Promise TV. Image credit: Rupert Goodwins

Between them, they do everything including case design and prototype production: even the circuit boards are laid out and etched in-house. Dominic also answers queries on the website.

Their business until now has been research and design consultancy for large commercial and government organisations. But now, a spin-off from some consultancy work has led them to build their first consumer product, Promise TV, which is ready for the one thing they can't do at home — full-scale production for the market.

24/7 set-top box

The idea is simple: a set-top box that records terrestrial digital Freeview TV. But unlike existing recorders that rely on you to tell them what to record, Promise TV takes a different approach: it records everything transmitted on all channels, TV and radio, all the time. If you want to watch something broadcast in the last seven days, it's waiting for you.

The professional version of Promise TV provides statistics on quality and outage status of TV reception. Image credit: Rupert Goodwins

Such catholic capture needs a lot of storage: in its present incarnation, a Promise TV box has seven terabytes across two 3.5TB drives. It also needs a lot of digital tuners; six, for the UK. But other than that, the concept is simple.

Yet it has some remarkable possibilities. For a start, it runs rings around the broadcasters' own online systems. Even iPlayer, the BBC's flagship video-on-demand service, misses a lot of the BBC's own output and has only a fraction of the total transmitted across the 40-odd channels on Freeview: in total, there are around 10,000 programmes a week across all channels, according to Promise TV. There are also some 200 films: Promise TV groups recordings by category, as well as by time and date, so you can treat it as a constantly refreshed movie-on-demand service.

The user interface is commendably simple — you pick a time over the past week by moving along a timeline and start watching. It's exactly as if you were watching live TV at that time. It's therefore impossible to miss a programme because the broadcaster changed the time of transmission due to previous overruns, and you can fast forward or reverse with absolutely no danger of running out of buffer.

Week-long storage

Programmes are normally deleted after a week, but you can choose keep a programme as long as you like. Kept programmes use up space on the hard disk. If you store a two-hour film, the week-long storage available to all other programmes shrinks by about 10 minutes.

Promise comes in a £1,990 professional version, which is what the company has primarily been selling so far, alongside the £995 seven-day model and the £599 three-day Promise Lite. As well as providing statistics on reception and channel outages, the pro version has a search feature. This not only looks for keywords in listings, it also stores and searches through subtitles: not as easy as it might seem, as these are transmitted not as text but as bitmap images.

With this search, you can become aware of a news story after it's broken, and look back over every news and factual programme that mentioned the subject or the people involved from before it happened. It's a powerful and unique way to capture an ephemeral yet comprehensive stream of themed content.

System components

The box itself is built around fairly standard components, with an FPGA (Field Programmable Gate Array — logic that can be reconfigured through software) chip handling the interface to the multiple multi-megabit streams from the tuners.

It also has an ARM processor co-ordinating the other circuitry, and...

...various off-the-shelf devices managing other input, output and coding duties. There are five wired Ethernet ports; one to connect to the internet and four to distribute content around a home or office. Their presence is one of the first signs of how the politics and practicality of providing such a service combine to help define how it works.

Christian Ludlam: high-speed digital processing, multi-tuner RF receiver and FPGA I/O processor expert at Promise TV. Image credit: Rupert Goodwins

Wired Ethernet — not wireless — has been chosen not just for quality reasons, but because it helps tidy up the rights issues. The system is designed, and in large part constrains the user, to operate only within a single home or office. That simplifies questions of legitimacy: it is broadly allowable to capture what you want from broadcasts for your own consumption, it is broadly forbidden to spread it any further. The internet port cannot send or receive any content: it is purely present for management purposes.

Software considerations

Anyone who has used a set-top box will know that they are invariably buggy, with firmware updates infrequent and by no means guaranteed to fix a problem. An internet connection means not only that updates can be sent immediately and invisibly, but there's a back channel for diagnosis and fault finding — all, potentially, without the user even knowing there's a problem.

The project itself was going to be called Promiscuous TV, until the spirit of the '60s got ditched.

The software is entirely written in-house. Early versions of the system ran on PC hardware and used OpenBSD. When the custom hardware was developed, it was decided to do the same with the software.

The underlying operating system is called PromiscuOS. The project itself was going to be called Promiscuous TV, until the spirit of the '60s got ditched, perhaps wisely, in favour of something less liable to scare the horses. Written in C and ARM assembly, the entire stack from physical layer through to the user interface is nonetheless designed to be portable to other processor architectures.

There are still some issues about content and legality: although Promise TV is sure that it's no more illicit than a video recorder, it's had a letter from Channel 4 offering a different opinion. The BBC, whose New Media department commissioned the first prototype as a design study, is more circumspect on the matter.

A Bush TV-22 from 1950: the first UK TV that could receive more than one channel and iconic mascot for Promise TV. Image credit: Rupert Goodwins

(Another one-off project for the BBC, which was a box the size of a large filing cabinet that stored the whole of the BBC's output for six months and delivered it in multiple formats on demand over the internet, was intended by its commissioner to demonstrate the potential of digital distribution to parts of the Corporation that might benefit from a sharper focus in this area. The demonstration was effective.)

Distribution challenges

The biggest issue remaining, however, is how to take the product to the customers. The UK has almost no consumer electronic production skills left, and thus no particularly suitable distribution channel.

Likewise, the marketing is going to be both difficult and delicate: although 10 minutes with Promise TV reveals how fundamentally it differs from existing recorders, it's a tricky concept to get from a quick skim of the specs. The team reports that it's not uncommon for potential customers to listen patiently to the pitch, nodding the while, and then ask, "So, how do you set up a timed recording?"

The cost is also an issue: in reasonable numbers, the company says it'll probably cost around £400 — which will seem a lot to people who assume that online services and sub-£100 digital recorders can do all they need. For anyone who's had to train and support non-technical family members in the care and use of either, though, it sounds like a bargain and a half.

Nevertheless, the thing works. Were Apple to announce something with identical functionality, it would be on News at Ten and the queues would be round the block. But the risk is that while Promise TV proves that world-class engineering can still happen in the UK in exciting and unorthodox ways, the vision and audacity behind it won't be matched by the country's marketing and production nous.