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Re: MOtion deblur

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pdaraja@gmail.com wrote:
> Hi all,
> I am dinesh, working on the restoration of 
> the motion blur due to fast moving of object. 
 > i have one doubt, if i want to deblur a
 > blurred image, why i need to add some
 > additive noise to recover them.

You first need to understand how
deconvolution works.  Assume a model of the
blurring process:
     Input(s) * Blur(s) = Output(s)
         where s is the space domain
         * is convolution
         and Input(s) is the original
             unblurred image

Transform into the frequency domain
     Input(f) x Blur(f) = Output(f)
         where f is the frequency domain
         and x is simple multiplication

Now rearrange:
     Input(f) = Output(f) / Blur(f)
         where / is simple division

Note that where the denominator is zero, the
division will introduce infinities.
Infinities are bad, and represent lost
information; there is no possible way to
recover it.

So, you have to introduce a "fiddle factor"
to produce a usable result, be it one that
contains artifacts.  One way to do this is
to introduce additive noise.  There are
other ways.

 > in addition to that why the deconvolution
 > algorithm requires the simulating of
 > motion blur to restore the deblurred image.

It does not.  However, you do need to
estimate the blurring function, Blur(s).
For constant velocity blur typically this
would be its direction and length.

-- 
Regards,
Martin Leese
E-mail: please@see.Web.for.e-mail.INVALID
Web: http://members.tripod.com/martin_leese/

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MOtion deblur pdaraja@gmail.com - 2016-10-26 23:57 -0700
  Re: MOtion deblur Martin Leese <please@see.Web.for.e-mail.INVALID> - 2016-10-27 11:05 -0600
    Re: MOtion deblur pdaraja@gmail.com - 2016-10-30 22:40 -0700
      Re: MOtion deblur Martin Leese <please@see.Web.for.e-mail.INVALID> - 2016-10-31 09:20 -0600
        Re: MOtion deblur pdaraja@gmail.com - 2016-11-01 00:25 -0700
          Re: MOtion deblur pdaraja@gmail.com - 2016-11-01 00:26 -0700
          Re: MOtion deblur Martin Leese <please@see.Web.for.e-mail.INVALID> - 2016-11-01 09:37 -0600
            Re: MOtion deblur pdaraja@gmail.com - 2016-11-02 23:12 -0700
              Re: MOtion deblur Martin Leese <please@see.Web.for.e-mail.INVALID> - 2016-11-03 08:51 -0600
                Re: MOtion deblur pdaraja@gmail.com - 2016-11-03 21:43 -0700
                Re: MOtion deblur dale <dale@dalekelly.org> - 2016-11-04 21:08 -0400

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