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Re: filmscanners: Noise correction algorithms



"Lynn Allen" <lalle@email.com> wrote:
> Since dust is always "white" on negs and always "black" on slides, while
> "noise" is usually lighter and "grain" is usually darker than the
> surrounding field of pixels, is this or can it be considered in the
cleaning
> algorithms?

If you could characterise the noise in a particular CCD you could remove
it using a fourier transform.  I doubt it would work with grain aliasing and
definitely not with dust because dust is too grossly random.  But it ought
to work effectively on CCD noise.

Noise removal under specific circumstances like shadows or highlights
might be a good thing to preserve details in other areas.

Rob





 




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