Re: Lots of questions

John Ingham (johningh@tafe.sa.edu.au)
Thu, 13 Mar 1997 10:40:00 +0930


On the 5th of March Peter Cole asked a number of questions on the CU-SeeMe
list which do not appear to have yet received an answer. So to the best of
my knowledge, here goes Peter...

>I am considering various video packages for DTVC and have some questions
>about CU-SeeMe. Could those of you in the know please help me out and
>answer some questions?
>
>Does CU-SeeMe offer clear audio?

This depends on the available bandwidth. Via a LAN the audio is quite
acceptable but I have yet to experience reliable audio via a 28,800 bps
modem using any compression algorithm. In my opinion, the best audio via a
28,800 bps modem is obtained by the use of "PowWow" which can be run
concurrently with CU-SeeMe, although for best results the transmit video
must be paused while speaking. Unfortunately, PowWow is not available for
the Macintosh platform.

>What conditions are required so that a user can achieve 10 FPS?
> - ISDN line?
> - 28.8 modem?
> - 100 Mb LAN?

This depends on the picture content. I have acheived 6 fps over a 28,800
bps modem provided I frame myself small in the picture and sit very still!
But if I make big movements the fps drops rapidly to 1 or 2 fps. A 64K
ISDN line would probably produce 10 fps under similar restrictions. But if
you wanted to pump out "broadcast TV" programming you'd probably need at
least 128 kbs to maintain 10 fps of continuously moving image. But be
aware that ALL participants of your conference would have to be similarly
connected.

>Is CU-SeeMe H.320 compliant?

No.

>Is CU-SeeMe T.120 compliant?

No.

>How good are the collaboration features?

This is hard to say. Compared to what? The White Pine Enhanced CU-SeeMe
comes with a "White Board" program which is fully collaborative in itself
including the ability to send and receive files. However, you cannot use
CU-SeeMe collaboratively with another third-party application.

>Does it use the MBone?

I believe the answer is "Yes" but I stand to be corrected by those more in
the know.

>Is there full-screen video? Color video?

No. Yes (White Pine Enhanced CU-SeeMe only)

>Is the codec always software driven?

Yes.

To ensure that you receive this Peter, I am sending it both to the list so
that others might pick up on any errors and or omissions, and directly to
you (because of the nature of some of your questions, I suspect you don't
continuously "haunt" the CU-SeeMe list).

John Ingham
Supervisor, Technical Operations, CALS (Centre for Applied Learning Systems)
Adelaide Institute of TAFE (Training and Further Education)
GPO Box 1872 Adelaide South Australia 5001
Ph: +61 8 8207 8550 Fax: +61 8 8207 8552
Email: johningh@tafe.sa.edu.au
Web Site: http://www.tafe.sa.edu.au/video-conf/
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