Re: [GnomeMeeting-list]Video quality

[Lawrence Manning <lawrence smoothwall org>]

On 30 Oct 2001, Damien Sandras wrote:

> I'm not sure that increasing the number of background blocks transmitted with each
> frame will give you a better quality. It will use a lot more bandwidth,
> but why should you send more background blocks as they remain the same
> in each frame ? I mean, the wall behind me, will not move, why should I
> transmit it again in each frame ?

Exactly.  I dont understand why the setting is even there.  Surely if the
block has not changed it shouldn't be sent at all.  What should be
settable is the number of blocks to send that HAVE changed.  Ie. if you
want to only send 1 or 2 blocks per second, then the person is going to
have to sit VERY still to be reconisable after a minute or so.  Whereas if
you send dozens of blocks per second, then the picture will update faster.
In my quick tests, it seems the update blocks makes little difference...

> Notice that the behavior of quality has changed in newer OpenH323
> libraries and bad quality settings give a better quality with less used
> bandwidth.

Strange indeed.

Anyway, I'm off now to compile CVS gnomemeeting.

Lawrence Manning

Development Team Leader and Author - SmoothWall - www.smoothwall.org
Email: `formail -z -x From: <thismail`