Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!rutgers!cbmvax!cbmehq!cbmger!peterk
From: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: CDTV vs. CD-I again!: CES is here
Message-ID: <1294@cbmger.UUCP>
Date: 4 Jun 91 15:01:40 GMT
References: <1991Jun2.180445.27763@cunixf.cc.columbia.edu> <1991Jun4.045255.16207@ncsu.edu>
Reply-To: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Organization: Commodore Bueromaschinen GmbH, West Germany
Lines: 23

In article <1991Jun4.045255.16207@ncsu.edu> kdarling@hobbes.catt.ncsu.edu (Kevin Darling) writes:
>
>Unlike CD-I, which can play interleaved sound off the disc _while_ also
>loading in new video/program/sound data, CDTV must first load in any
>prerecorded audio data and then play it back from memory thru its normal
>Amiga 8-bit D/A system.  I'm stunned.  Can this be totally correct?

It's all a question of bandwidth. If you want to play real CD audio,
then the read head is just on that audio track and can't read anything
other. If you read other audio data (computer digitized with lower
sampling rate/resolution than real CD), then you must live with that
170 KB/s bandwith plus considerable positioning times. So also here
you could read only audio exclusively (if at all possible), and must
play graphics/animations from memory. Or, alternatively, you play a
graphics animation directly from disc and play the accompanying sound
from memory. As far as I know, the bandwith is so limited that you
can't do both at the same time (we have no hardware data compression).

(Disclaimer: I only know this from theory, being no real expert.)

-- 
Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk