Videotex

March 18, 2019

Category: Research Shorts Date: 2019/03/18 Tags: #art #hacks —

Videotex (or "interactive videotex") was one of the 
earliest implementations of an end-user information system

Videotex is interesting to me, not just because of its aesthetic qualities, but because it attempted to adapt existing systems — the broadcast TV and telephone systems — to new, interactive uses.

Several systems of interest are:

Minitel in France, by far the most popular and widely adopted system. It was unique in that it was somewhat decentralized.
Prestel in the UK, which was operated by the General Post Office. It has some really intriguing implementation details outlined on the Wikipedia page.
Viewtron in the US, which was operated by AT&T and Knight-Ridder publishing. It was a dismal failure, but produced an aesthetic af video:

The Viewtron interface, in particular, is intriguing to me. It used a language called NAPLPS, an extremely low-bandwidth graphics language that could produce complex graphics using terse object commands. I would love to get my hands on an implementation of this language and do something with it.

Another interesting avenue of research is the Singapore Teleview system, which transmitted imagery via “Full Field Teletext transmissions from dedicated data inserters/UHF TV Transmitters.” My understanding is this means imagery was transmitted the same way TV signals were transmitted! I’d love to reimplement this.

Finally, TELSTAR seems to be a re-implementation of a PRESTEL-like server, which can apparently be accessed fromRISC OS running on a Raspberry Pi (another thing I learned, Raspberry Pis can run RISC OS.) Another project might be building a traditional modem interface to a system like TELSTAR on top of Twilio or similar.

This article is also a lot of fun.