Origin of "partition" in storage devices

[Chris Elmquist]

On Tuesday (02/01/2022 at 01:41PM -0500), Chris Zach via cctalk wrote:
> > Which came first CLV CDs, or CLV LaserDiscs?
> 
> Laserdiscs by far. Only the very first models played CAV only.
> 
> CAV is nice because you can freeze frame without a frame buffer.

Yes!  My dad did some of the first work on LaserDiscs-- built 3Ms plant
for making them in the late 70s.

As a result, we always had "samples" from the production line to watch
at home and numerous different players to check out.

CAV allowed you to freeze frame, step forward and back and never loose
frame sync.  You had a solid picture no matter whether it was playing,
stepping or paused.  But, you also got at most about 30 mins / side on
a disc and so a movie was 3 or 4 discs in length.

With CLV, you got more on the disc, about an hour per side or a whole
movie on one disc but you could not smoothly pause or step it.  Some
players would completely disallow it and some would display the torn
image with pieces from multiple adjacent frames.

CAV was used a lot for educational discs where the player was controlled
by a computer (in one case we had, a Sony CP/M machine) which combined
the interactive educational software on the computer with video content on
the disc.  The Sony computer had a genlock system in it so that it could
overlay computer graphics on the video signal from the disc player.

This was 1979 or 1980 if I remember correctly.

Chris
-- 
Chris Elmquist