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From: ImageAnalyst <imageanalyst@mailinator.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Modulation Transfer function
Date: Mon, 12 May 2008 18:18:57 -0700 (PDT)
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On May 8, 10:56=A0pm, "Ahmed Zaki" <azak...@gmail.com> wrote:
> How can I calculate the Modulation Transfer function for an
> image? Thanks.. AZ

------------------------------------------------------------------------
AZ:
You either need the point spread function (and then you just take the
magnitude of the Fourier tranform of the PSF), or you need an image
with a bunch of cycles (e.g. sine waves or black and white line pairs
or different frequencies) that you can measure the contrast of and
build up the MTF frequency by frequency.  So which do you have?  If
you have neither, you may be out of luck.  You might be able to
estimate it if you have a known, perfectly sharp edge in the image
(that gets blurred as it gets imaged).  I think you can estimate the
PSF if you have a known point or known edge in your image.  What kind
of image do you have?
Regards,
ImageAnalyst