Date   : Wed, 17 Aug 2011 01:56:54
From   : ats@... (Adam Sampson)
Subject: [Bulk] Re: [BeebSoc] Re: Amstrad emailer / DataCentre

Mick <rs423@...> writes:

> Can you play these discs on anything else? I've never had a Domesday
> so this is a genuine question.

You can play the video on any LaserDisc player. The discs are CAV, so
you can freeze-frame them to step through the still images.

Reading the data is a bit tricker: it's stored using CD-style EFM, in
essentially the same way as digital audio on later LaserDiscs. The
Philips VP-415 player that comes with the Master AV system makes it
available through a SCSI interface, but I don't think it would be
terribly difficult to build a decoder if you couldn't use a VP-415 for
some reason; the VP-415's decoder just uses one of Philips' CD player
chipsets, with a little Z80 system to pick apart the 44k1 "audio" stream
into data blocks.

If I were trying to archive a Master AV disc, I'd use a really high-end
LaserDisc player to grab the video frames one by one, with lots of
averaging to minimise noise, and use the VP-415 to grab the data.

-- 
Adam Sampson <ats@...      >                         <http://offog.org/>