Re: new to the list -- with questions

John Ingham (johningh@tafe.sa.edu.au)
Mon, 1 Sep 1997 13:54:24 +0930


Jason Williams, perhaps better known as "Streak" commented on my reply to
David Mason. Firstly, thankyou Streak for your comments, but it seems that
your experiences with CU-SeeMe are different than mine!.

>> I'd recommend you get "PowWow" from Tribal - something like WWW.tribal.com
>> - it is a free non-video conferencing client with MUCH better sound than
>> CU-SeeMe. By running the two applications at the same time you'll be
>> better off by far than using CU-SeeMe's audio,
>> 1. because PowWow's audio is better anyway, and
>
>That's debatable..I've never heard PowWow's audio specifically..but I have
>heard about 3-4 other package's audio (Freevue, Internet Phone, etc).
>I've always had the best audio quality from CU-SeeMe. Contrary to some
>people's opinions, audio on CU DOES work over a modem and if done properly
>with the right settings, is quite intelligable. I've talked for several
>minutes at a time and people have heard me quite clearly. On a 1-1
>connection, audio works wonderfully as long as you pause your video.

Most of my CU-SeeMe experience has been between Australia and the USA. I
have almost never found CU-SeeMe's audio over that route to be as good as
PowWow; indeed CU-SeeMe audio has almost never been really usable at all.
It does vary from time to time, but I wouldn't be surprised if the shorter
the route the more reliable the audio. So if Streak's experience has been
short-haul CU-SeeMe then his comments may be more relevant to David Mason's
intended use.

>> 2. because in my experience with 2 datastreams running in parallel your
>> total through-put will be better than trying to squeeze video + audio into
>> 1 data stream. Rarely have I been bandwidth-limited by my own modem
>> connection, it's usually somewhere else in the internet, so running 2 data
>> streams gives you two bites of the cherry!
>
>This doesn't make sense to me. Bandwidth is bandwidth. It's all the same
>pipe whether you stream water thru it or sewage. Maybe I misunderstood
>your analogy (you're comparing using video+audio from CU-SeeME with video
>from CU-SeeMe and audio from PowWow).

I think you understood me just fine. It may be all the same pipe but the
major restriction may NOT be the local 28.8 K modem, it could well be
elsewhere in the internet. So although both CU-SeeMe & PowWow have to
share the local 28.8 kbs "pipe", I find that *that* rarely is the limiting
factor regarding end-to-end bandwidth on a long haul. For example, when
down-loading the Pre-release version of White Pine EnhCU-SeeMe over the
weekend, it was *much* faster to simultaneously down-load the 4 components
(at 800 Bytes/sec each x 4 = 3.2 kilo Bytes/sec) than a single down-load of
the combined package (at 800 Bytes/sec x 1 = 0.8 kilo Bytes/sec). I
realise that this may have been due to a bottleneck at White Pine's server,
but it could also have been anywhere else between them and me, and it is
very typical of my experience of downloading and of CU-SeeMe on the
Internet. Where resources are shared between all users it does pay to have
two or more "bites of the cherry" - sure it's unfair, but that's life.

>In this case, I'd have to say using
>CU-SeeMe's audio would be better because CU knows when to start pausing
>the video unless you pause manually. If you run another audio stream from
>another program, CU-SeeMe can't regulate the rates as well since all it
>sees is more packet loss. Enhanced CU-SeeMe is pretty good about pausing
>the video so audio can come thru.

In my experience, the Macintosh CU-SeeMe seems to handle this better than
Windows. When I use my Mac I don't have to pause the video before using
the CU-SeeMe audio but I DO have to pause video on my Windows PC before
speaking. FWIW.
>
>Don't forget the added memory requirement...now instead of one program
>that has to be loaded to communicate, you need two. More system resources
>being used.
>
Co-running CU & PowWow doesn't seem to be a problem on my PC, they both
seem quite ignorant of each other's presence!

>> One thing though, at 28,800 bps you'll find that you'll usually have to
>> freeze your camera when speaking because 28,000 bps is not enough to
>> support picture and sound at the same time.
>
As stated before, on the Windows PC (which is the only platform supported
by PowWow) I find I have to manually freeze the video before speaking
anyway so that's not an additional problem.

>Too bad the final release of 3.1 for the Mac won't have the low bandwidth
>audio codecs in them. I can usually send audio (voice only though..no
>music or anything) at 8kbps and it's understandable, and I can still send
>video at the same time. Why White Pine is doing away with that in the Mac
>version I don't know.
>
I found that my 70 MHz PPC Mac doesn't have enough "grunt" to run the low
bandwidth audio codecs; maybe they haven't been optimised enough yet for
the PPC and would delay the final release of 3.1 for the Mac.

Anyway Streak, thankyou again for your comments ;-)

John Ingham
Supervisor, Technical Operations, TLC (Tele-Learning Consortium)
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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