Re: [GnomeMeeting-list] The Jitter buffer got it

[Damien Sandras <dsandras seconix com>]

Le jeu 05/06/2003 à 16:09, murugesan a écrit :
> Hello,
>      Thankx for Damien. I thought that jitter is a buffer to store all
> the packets. But now it seems that it is measure similar to time to
> live(TTL) (but not exactly the same). Am I correct :).

More or less. It is a buffer that stores audio packets for a given
amount of time before playing them to the speakers. As packets do not
necessarily arrive in the correct order, and as some of them can be
delayed (or lost), it is required or the voice would be scrambled if
packets were played directly.

I think you can find a more precise definition on google.com, but at
least I hope you got the general idea :)

> 					Murugesan N
> 
> murugesan <murugesan visolve com>
> 
> 
> 
> On Thu, 2003-06-05 at 19:29, Damien Sandras wrote:
> > Le jeu 05/06/2003 à 15:54, murugesan a écrit :
> > >              How is that? Assume that I am having a bad network delay
> > > and I have some fixed jitter buffer.For bad network delay, it may take
> > > more time to fill the buffer and less time to fill it for the other
> > > case. Then how comes the matter of jitter buffer size.Irrespective of
> > > the size of jitter buffer, delay will be there in a highly congested 
> > > network.
> > 
> > I'm not sure you understood correctly, so I'll explain things in another
> > way.
> > 
> > Imagine you have a network for which many packets arrive out of order
> > and that it takes 200ms approximatively to get all packets and be able
> > to play them. If you the jitter is < 200 ms, the voice will be
> > scrambled, if the jitter is > 200 ms, you will just have enough time to
> > put things in the right order.
> > 
> > Theorically you can always put a jitter big enough to be able to have a
> > correct voice quality, but a delay of more than 500ms is not acceptable.
-- 
 _	Damien Sandras
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