Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!ut-emx!ccwf.cc.utexas.edu
From: clouds@ccwf.cc.utexas.edu (Kathy Strong)
Newsgroups: comp.ivideodisc
Subject: Re: How much can be put on a videodisc
Message-ID: <40112@ut-emx.uucp>
Date: 24 Nov 90 19:58:38 GMT
References: <3863@mindlink.UUCP> <18@anaxagoras.ils.nwu.edu>
Sender: news@ut-emx.uucp
Reply-To: clouds@ccwf.cc.utexas.edu (Kathy Strong)
Lines: 62

In article <18@anaxagoras.ils.nwu.edu> chung@ils.nwu.edu (Mark Chung) writes:
>In article <3863@mindlink.UUCP> a544@mindlink.UUCP (Rick McCormack) writes:
>> Rumors have abounded for about 5 months that there is a version of
>> CLV being tested that includes a _frame grabber_ - a memory unit that 
>> will hold individual frames for use as stills.  This would give us access 
>> ...
>> Actually, there is no reason why CLV units could not be equipped with 
>> built-in frame grabbers capable of storing from 1 to 4 frames at a 
>> reasonable price.
>
>The Pioneer LDV-8000 has a frame memory, so it handles still and other 
>special effects (step, fast forward/reverse, still with independent audio) 
>with CLV (I just tried it). 
>However, we are using CAV disks in order to support stills on older 
>machines such as the
>LDV-4200 and the LC-V330 (autochanger).  Our prototype system uses a
>video digitizer (RasterOps 364) which puts the image on the Mac monitor. 
>This board also
>can freeze the image, but in some situations we use a tv monitor, and the
>player must freeze the image.
>
>The Pioneer manual says that in order to support CLV special effects the 
>disk must
>be recorded with a second code. Our own disks and the Nat'l Geographic 
>disks seem to
>have this;  is this fairly standard?
>
>Mark


We are using Pioneer LDV-8000s and they do indeed work fine with CLV discs.
The extra code (I forget its name) is required to address the disc down to
the frame level; otherwise, you can only search to the nearest second, I
believe. It seems to be pretty standard to include the code.

Authoring software is notoriously intolerant of the quirks of CLV--for example,
one authoring package we had a heavy investment in would simply choke on
any frame number higher than 65535. An unfortunate limitation on a disc with
108,000 frames... We got them to patch it in the search function, but from
time to time one still finds cropping up the assumption that a short integer
is all one will ever need as a frame number. Most annoying, especially as
the software doesn't give you any obvious kind of error alert--it simply
truncates the long integer into a short one (that is, gives you the number
mod 65535) and goes its merry way.

The original poster (Rick?) says there's a rumor of CLV units with frame
grabbers--this implies that CLV units don't currently have them. Is this
referring to "low-end players"?  Just how "high-end" does a player have to
be before having a frame-grabber (which is actually, as I tried to explain
in an earlier posting, a function which DISABLES video pass-through--surely
not that difficult to implement)? I have only worked with the 8000s, and 
am not really familiar with the functions of 4200s, 6000s, and so on...

--K


-- 
...........................................................................
:   Kathy Strong               :  "Try our Hubble-Rita: just one shot,     :
:  (Clouds moving slowly)      :   and everything's blurry"                :
:   clouds@ccwf.cc.utexas.edu  :                           --El Arroyo     :
:..........................................................................: