Path: utzoo!mnetor!uunet!nbires!hao!ames!pioneer!hultquis
From: hultquis@pioneer.arpa (Jeff P.M. Hultquist)
Newsgroups: comp.graphics
Subject: video recording
Message-ID: <5420@ames.arpa>
Date: 1 Mar 88 22:57:27 GMT
Sender: usenet@ames.arpa
Reply-To: hultquis@pioneer.UUCP (Jeff P.M. Hultquist)
Organization: NASA Ames Research Center, Moffett Field, Calif.
Lines: 32


	A while back I asked for info on "cheap" single
frame video recording.  One netter directed me to the
proceedings of the Third Usenix Conference on Computer
Graphics.  It includes a paper on a simple video
controller which used one of the audio tracks for timing
information.  Modern 3/4 inch decks use this concept;
look for the magic words "SMPTE time code."  A Sony
BVU-950 (a "typical" SMPTE deck) weighs in at about
fifteen thousand dollars.  Has anyone heard of SMPTE
decks for less than this?

	Another option is to use "time lapse" recorders,
such as those used for building security applications.
These cost in the three thousand dollar ballpark, and
typically record four frames at a set interval or in
response to an external signal.  Using such a box, you
_ought_ to be able to record videos at eight images per
second.  I talked with a field engineer at a "major
electronics manufacturer" about such a scheme.  His
claim was that these units do not have mechanical or
electronic "smarts" to accurately position the tape to
give clean joins between "bursts."  The finished
animation will, therefore, have some noise across the
top of the screen.  No problem if you want to identify
bank robbers, but not so good for animation.

--
Jeff Hultquist		hultquis@pioneer.arc.nasa.gov	
(415) 694-4970  	{uunet,ihnp4,decwrl}!ames!pioneer!hultquis
Jeff Hultquist		hultquis@pioneer.arc.nasa.gov	
(415) 694-4970  	{uunet,ihnp4,decwrl}!ames!pioneer!hultquis