Displayrate in x0rfbserver

"Beerse, Corné" c.beerse@torex-hiscom.nl
Wed Nov 13 10:30:00 2002


> -----Original Message-----
> From: jay chandra [mailto:jc9978@india.com]
> 1)so what could be done to make x0rfbserver support higher 
> fps cause i find that x0rfbserver is noteven supporting   2fps.
> 2)could we do that manipulation?
> 3)And what is the option Xshm and Xtest for?

What's the use if this higher fps?
Is it to avoid flashy displays to avoid bad eyes? Set the display frequency
at the viewer machine, vncviewer will follow.

Is it to view videos that display at the remote site? Forget it. See my
(raw) calculations in my previous mail. you need a 1-Gigabit network for the
bandwith. Then you need a verry fast processor for the vncserver machine
(there is and will be no acceleration at this point) And you need a verry
fast vncviewer machine that can co-op with the bandwith.

An other look on displaying video's: the Mpeg 1 standard is designed to have
a PAL or NTSC (roughly 600x400) display at 25 or 30 fps over a 150MBit
stream (1 x CDRom speed!). Don't expect that troughput with slower hardware
(100Mbit network), less compresson (no mpeg compression in vnc) and software
driven (most mpeg viewers use hardware acceleration). Then at the
compression side (the vncserver) the required power is roughly 4 to 10 times
higher than for decompression.

I find it reasonably fast if you have 2 full-screen updates per second in a
vnc session. Most times, I get less.

Have you tried the vnc for XFree (see http://xf4vnc.sourceforge.net/) It
does roughly the same in a slightly different way.


CBee