From: ldo@waikato.ac.nz (Lawrence D'Oliveiro, Waikato University)
Subject: Re: Rumours about 3DO ???
Organization: University of Waikato, Hamilton, New Zealand
Lines: 52

In article <1993Apr16.212441.34125@rchland.ibm.com>, ricardo@rchland.vnet.ibm.com (Ricardo Hernandez Muchado) writes:
> In article <1993Apr15.164940.11632@mercury.unt.edu>, Sean McMains <mcmains@unt.edu> writes:
>
> |>
> |> Ricardo, the animation playback to which Lawrence was referring in an
> |> earlier post is plain old Quicktime 1.5 with the Compact Video codec.
> |> I've seen digitized video (some of Apple's early commercials, to be
> |> precise) running on a Centris 650 at about 30fps very nicely (16-bit
> |> color depth). I would expect that using the same algorithm, a RISC
> |> processor should be able to approach full-screen full-motion animation,
> |> though as you've implied, the processor will be taxed more with highly
> |> dynamic material.
>
>
>    Sean, I don't want to get into a 'mini-war' by what I am going to say,
> but I have to be a little bit skeptic about the performance you are
> claiming on the Centris, you'll see why (please, no-flames, I reserve
> those for c.s.m.a :-) )
>
>    I was in Chicago in the last consumer electronics show, and Apple had a
> booth there.  I walked by, and they were showing real-time video capture
> using a (Radious or SuperMac?) card to digitize and make right on the spot
> quicktime movies.  I think the quicktime they were using was the old one
> (1.5).

That is in fact the current version (it only came out in December).

>    They digitized a guy talking there in 160x2xx something.  It played back quite
> nicely and in real time.  The guy then expanded the window (resized) to 25x by
> 3xx (320 in y I think) and the frame rate decreased enough to notice that it
> wasn't 30fps (or about 30fps) anymore.  It dropped to like 15 fps.  Then he
> increased it just a bit more, and it dropped to 10<->12 fps.
>
>    Then I asked him what Mac he was using... He was using a Quadra (don't know
> what model, 900?) to do it, and he was telling the guys there that the Quicktime
> could play back at the same speed even on an LCII.
>
>    Well, I spoiled his claim so to say, since a 68040 Quadra Mac was having
> a little bit of trouble.  And this wasn't even from the hardisk!  This was
> from memory!

My test movie was created at 320*240 resolution, it wasn't being scaled up.
Scaling was a very CPU-intensive operation with the original QuickTime (1.0);
the current version has optimizations for ratios like 4:1 (160*120 -> 320*240),
but even so, I'm prepared to believe that the performance isn't as good as
with playing back an actual 320*240 movie. I haven't done any numerical
measurements for scaled playback.

Lawrence D'Oliveiro                       fone: +64-7-856-2889
Computer Services Dept                     fax: +64-7-838-4066
University of Waikato            electric mail: ldo@waikato.ac.nz
Hamilton, New Zealand    37^ 47' 26" S, 175^ 19' 7" E, GMT+12:00
