Re: 28.8 and 0 frames per/sec?

Gordon F. Ross (gfross@netcom.com)
Wed, 28 Jun 1995 04:20:59 -0700 (PDT)


Using the non-audio version of PC Cu-SeeMe: Even with an ISDN connection
with a speed potential of up to 128kbps, I often "receive" video images at
0 fps and even down to 0 kpbs. I have learned (assumed) that much depends
upon the speed which the "sender" is using and what I will call the
"Internet flow" of the moment.

"Senders" with a 14.4 or 28.8kbps modem are really "out of the picture"
most of the time; I rarely receive from them faster than 1 fps, if that,
and than 5-10kbps.

"Senders" with ISDN or faster connections are a delight to view,
especially if they are "sending" at a fast rate (50kbps and above). Their
fps varies from 0 (yes, at times it *is* 0) to 12 fps (rarely above that,
so far) and from 0 (seldom) to 80kbps -- usually hovering in the 40 to
60kbps range. When the fps gets up to 6 to 8 fps, the video image finally
becomes reasonably satisfactory as regards flow of movement. I found that
Stephan in Germany [Stephan@de] (using public reflector 132.236.91.204 --
Cornell, I think) is a good example of a reasonable flow. (I am in San
Francisco, btw, and usually do my viewing between midnight and 6 a.m. PDT.)

I have discovered that there seems at times to be little correlation
between the fps and the kpbs. I have seen 6 fps and 0 kpbs as well as 0
fps and 50kbps. On the whole, the fluctuation is very great.

With the pre-release Beta version of the audio PC Cu-SeeMe, I was able to
hear the audio portion of the NASA Select TV "broadcast" (158.36.33.5) --
about 4 by 4 rather than 5 by 5, good enough, however, to make out what
was being said. What I found puzzling, though, was the poor video --
seldom above 1 fps and 10kbps. In other words, the audio came through
better than the video! And only one 56k line of my ISDN connection was in
use, indicating that the flow of data from 158.36.33.5 was not enough to
"kick in" the second line. The video was also poor (about the same) when
I switched to the non-audio PC Cu-SeeMe (W0.34b5). Apparently they were
not "pumping out" enough data to get the fps up to a reasonable speed (5
or greater). I don't know what else could have caused the very slow rate
of 0 to 1 fps and 5 - 10kbps (I don't have video camera yet, so I don't
know how the "sender" controls the speed of the outgoing data).

Hope this sheds some light.

Gordon
gfross@expressway.com
gfross@best.com
gfross@netcom.com

On Mon, 26 Jun 1995 dbarlow@spectra.net wrote:

> Hi all I have gotten varying accounts now of video frame rate. I run 28.8 baud modem on PPP account 486-66 8 meg ram ,ver .65B1. A few people say 0 frames per second is to be expected with a 28.8 line. BUT then others say they get 1-3 with 14.4 baud line! Still others say they are getting poor audio on 28.8 lines. WHAT GIVES??
> I get pops and wheezes for audio not even CLOSE to intelligable and video is always 0 frames with 5-25 kbps showing. still photos show maybe 5 frames/sec but moving video is a jerky 0 frames. I wish to know if my system/internet is screwed up or what goes on here please <S>
> 1 final question I read all the faqs on cu-seem(hardly any to read)
> where do I find the past list of questions people have been asking in this group?
> the mailer help file is less then useless
> Kerry