[comp.sys.amiga.hardware] CDTV vs. CD-I again!: CES is here

es1@cunixb.cc.columbia.edu (Ethan Solomita) (06/03/91)

	I just finished reading a clarinet report on summer CES
highlights. The only CD-I vendor it mentioned as being at CES was
Magnavox. Their CD-I system will be shipping by October with a
list price of $1,400. No other companies were mentioned. They
mentioned "50 titles" to be released, but didn't name them. This
report sounds mighty good for CDTV, especially if software for it
keeps shipping!
	-- Ethan

Now the world has gone to bed,		Now I lay me down to sleep,
Darkness won't engulf my head,		Try to count electric sheep,
I can see by infrared,			Sweet dream wishes you can keep,
How I hate the night.			How I hate the night.   -- Marvin

kdarling@hobbes.catt.ncsu.edu (Kevin Darling) (06/04/91)

>      I just finished reading a clarinet report on summer CES
> highlights. The only CD-I vendor it mentioned as being at CES was
> Magnavox. Their CD-I system will be shipping by October with a
> list price of $1,400. No other companies were mentioned. They
> mentioned "50 titles" to be released, but didn't name them. This
> report sounds mighty good for CDTV, especially if software for it
> keeps shipping!

Yes, Magnavox (and I think Panasonic) will be the first brandnames here.
Prices will be discounted, no doubt.  Sales start in October, but
I'm beginning to see quite a lot of CD-I press coverage already --
including last week's announcement that Nintendo has licensed its
games to be put onto CD-I discs.

Also, the June 1991 VIDEO magazine ran a short review of CDTV, which
at least did answer one large question I had asked about here before:

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?

kevin <kdarling@catt.ncsu.edu>

mks@cbmvax.commodore.com (Michael Sinz) (06/04/91)

In article <1991Jun4.045255.16207@ncsu.edu> kdarling@hobbes.catt.ncsu.edu (Kevin Darling) writes:
>Also, the June 1991 VIDEO magazine ran a short review of CDTV, which
>at least did answer one large question I had asked about here before:
>
>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?

Yes and no.  We can play direct CD audio.  We can also play Amiga style
audio.  The Amiga style audio takes less disk space and thus you can have
much more of it on the CD.  (24 hours or some such large numebr)  Since
the way the hardware works, you can play continuous sounds from the CD
in Amiga mode and still load data at the same time.  The data will load
slower since you also are using some of the data bandwidth to load more sound.
If you play a sound "Loop" then the data will load just as fast as with
no sound.  Remember, CDTV still has all of the benefits of the Amiga,
including the Paula chip, which has the DMA driven sound channels.

/----------------------------------------------------------------------\
|      /// Michael Sinz  -  Amiga Software Engineer                    |
|     ///                   Operating System Development Group         |
|    ///   BIX:  msinz      UUNET:  rutgers!cbmvax!mks                 |
|\\\///                     When people are free to do as they         |
| \XX/                      please, they usually imitate each other.   |
\----------------------------------------------------------------------/

peterk@cbmger.UUCP (Peter Kittel GERMANY) (06/04/91)

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

es1@cunixb.cc.columbia.edu (Ethan Solomita) (06/05/91)

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?
>
	Does this mean that a CDTV application can't use the CD
to play back sound? I really doubt it. The little bit I heard
sounded better than Amiga quality. Also, the CD light would be on
while sound is playing.
	What DOES make sense is that the program can't be loading
in graphics data while playing CD sound. I believe you've
mentioned that this is something CD-I CAN do. I think it is
pretty safe to say that this problem will be solved over time,
assuming that CDTV does take off and it gets good support behind
it. But, for now, it is a limitation.
	Besides, most current programs are just simple ports
anyway. 8-)

>kevin <kdarling@catt.ncsu.edu>

	-- Ethan

Now the world has gone to bed,		Now I lay me down to sleep,
Darkness won't engulf my head,		Try to count electric sheep,
I can see by infrared,			Sweet dream wishes you can keep,
How I hate the night.			How I hate the night.   -- Marvin

swalton@corona.csun.edu (Stephen Walton) (06/06/91)

In article <1991Jun2.180445.27763@cunixf.cc.columbia.edu>
es1@cunixb.cc.columbia.edu (Ethan Solomita) writes about CES and
CDTV.  On the morning of 4 June, National Public Radio's Morning
Edition program aired a major report (4 or 5 minutes?) about CES,
and the only specific products talked about were CDTV (most of
the report) and a quasi-joke thing called The Biological Clock.
The reporter highlighted CDTV as being the only thing at the show
which wasn't just a rehash of existing technology.  A CBM rep
(didn't catch the name, but had a British accent) was given a
good deal of air time---he played an excerpt from M.L. King's
"I have a dream" speech on the air.
-- 
Stephen Walton, Dept. of Physics & Astronomy, Cal State Univ. Northridge
    "Lately it occurs to me/What a long, strange trip it's been"