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From: ImageAnalyst <imageanalyst@mailinator.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: SNR and imnosie
Date: Wed, 1 Jul 2009 18:07:03 -0700 (PDT)
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On Jul 1, 7:41 pm, "Rami AbouSleiman" <rdabo...@oakland.edu> wrote:
> to be more clear,
>
> I have an image and I am inducing Gaussian noise through imnoise.
>
> I use this image as an input into a specific system and the system fails when i put imnoise var of 0.15. (it works for var < 0.15)
>
> I want to be able to say that the system was able to tolerate a SNR of X?
> Find X?
>
> Thanks

----------------------------------------------------------------------
Rami:
I don't know what this system is, nor the manner of failure.  But
apparently you do, so the only way is to try increasing the noise
until the system fails, according to your definition of "fail."  At
that point, you will know X.  Since you know "input" and I, you can do
SNRWhenFailedAveragedOverAllPixels = mean(mean(input ./ (I - input)));
(Note the dot slash instead of just slash)
Good luck,
ImageAnalyst