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Subject: Re: Lossy video transmission
Date: Sun, 14 Dec 2008 08:52:01 +0000 (UTC)
Organization: American University of Sharjah
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thankyou for your quick reply,
i know what to do, but can you help me on how to do it.


"Nasser Abbasi" <nma@12000.org> wrote in message <q831l.14040$Ws1.2721@nlpi064.nbdc.sbc.com>...
> 
> <please do not top post>
> 
> >
> > news:gi2bgg$c4c$1@fred.mathworks.com...
> >> >I am trying to simulate a video transmission over lossy wireless channel 
> >> >in
> >> >Simulink. My project is at the initial stage so there need not be actual
> >> >transmission. I just need to introduce errors so that the video played 
> >> >at
> >> >the receiver is choppy, jittered, loss of data. how do i do that?
> >> > I have so far used the video and image processing blockset in MATLAB
> >> > r2008a to insert a video source and viewer. I need to add errors in
> >> > between these.
> >> >
> >> > please help me
> >>
> >> I do not know what the "lossy" part has to do with this. If you want to 
> >> just
> >> simulate noise in the message itself, then add AWGN noise to the message
> >> before the receiver end. This is the most basic way to add noise to a
> >> message which account to noise in the transmission channel and to thermal
> >> noise at the receiver side as well
> >>
> >> --Nasser
> 
> 
> >> "Sohaib Mansoor" <contact.sohaib@gmail.com> wrote in message
> > what I mean is that the video at the receiver's end should be 
> > discontinuous,  with some frames missing as well.
> > I want it to be simple at this stage, so something in between the source 
> > and the viewer, which could randomly drop frames with a certain 
> > probability should be sufficient. Any ideas?
> >
> > thanks in advance
> 
> Ok. So what you want is 'custom' made noise.
> 
> Then may be just add a block before the receiver end, where it accepts the 
> message on one end it does whatever it wants, and generates the result. This 
> block/function could drop a frame, delay transmission, or do whatever you 
> think needed to simulate the type of noise you want.
> 
> Decide of probability distribution to use (flip a coin, or whatever), and 
> based on this, do the damage you want to the message, when done, hand it 
> over to the receiver end.
> 
> --Nasser
> 
>