Re: QuickCam use report

Michael Sattler, San Francisco (EST)
Mon, 28 Nov 1994 15:16:42 -0500

At 22:09 11/27/94, Alan Larson wrote:
> The first observation was that the QuickCam gave me sound input
>capabilities. This was quite welcome, since the Mac IIcx did not
>have any other form of sound input. Our 56K line to the internet
>may continue to make sound impractical with the outside world,

You'll get much better video performance if you get an external microphone,
since any sound bits have to compete with video bits to get down the serial
line to your Mac.

> With CuSeeme, the extra load of processing the data from the
>QuickCam on the serial port made the Mac quite noticably slower.
>This was initially noticed when I tried playing with the sound
>controls, but also was painfully obvious when dealing with other

That's what happens when you do processing in software (your Mac's CPU)
rather than in hardware (on a self-contained add-on board).

>...What was happening was that the image brightness was
>changing from one scan to the next. This was apparently because my
>office is lit by flourescent light, which was flickering with the power
>line. (I didn't realize that it flickered that much.)

This is a potential boo-boo (sorry, I didn't want to be technical :-)
because that difference in brightness is probably seen by CUSM as a change
in scene, and it'll all get transmitted.

> It seems that some caution should be recommend with the possibility
>of the QuickCam using unexpected amounts of bandwidth.

For the preceeding reason.

Michael Sattler <> San Francisco, California
(2179 K)
LOOKING FOR WORK: technical manager, software engineer, trouble-shooter
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