RE: D-Cam

John W.Osborne (josborne@magna.com.au)
Fri, 30 Aug 1996 12:06:50 +-1000


Given the choice, I would prefer speed at a lowly level of 4 or 16
'scales" of grey to 64 or 128 at a turtle's pace.

Your kilometreage may differ.

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From: Jacqueline Chados[SMTP:jackie@sri.webmate.com]
Sent: Friday, 30 August 1996 0:46
To: CU-SEEME-L@cornell.edu
Subject: Re: D-Cam

On Wed, 28 Aug 1996, Don Castella wrote:

[bunch 'o words]

> My question is: Could the D-Cam be
> used in the 256 gray scale mode with Cornell or WP CU-SeeMe on a PC? If so,
> it would be a great improvement over the 64 gray scale mode I am currently
> using on the BW Connectix QuickCam.

I didn't realize that this was an issue. Thanks to Don's question I
explored this with the D-Cam. The D-Cam does work with CU-SeeMe in 256
gray mode. I connected to myself and watched the 256 gray images come back
into my computer. At 256 gray, frame rates were slower but the images were
less contrasty and more detailed. It seemed that the biggest benefit was
that more detail was visible in the darker areas of the image. Perhaps
someone who is familiar with the video algorithms could explain what is
happening.

The interesting thing is that, since the image size is so small, the 64
gray mode isn't all that terrible. There is definitely more detail in the
256 gray image, but the relatively small image size seems to put a cap on
the benefits of the 256 gray mode. I think that the bottom line is that
the 256 gray image is better, but how much better will depend upon what is
actually in the image. It's nice to know that the D-Cam does have the
increased capability for when it's needed.

Regards,
Jackie