Newsgroups: sci.image.processing
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From: az@saturn.analog.com (Alex Zatsman)
Subject: Re: Looking for accurate 2D interpolation algorithms.
In-Reply-To: rfulton@atom.ansto.gov.au's message of 25 Jan 1995 16:41:13 +1100
Message-ID: <AZ.95Jan27161712@saturn.analog.com>
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Organization: Analog Devices Inc, Norwood MA, USA
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Date: Fri, 27 Jan 1995 21:17:12 GMT
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In article <3g4o9p$d8g@atom.ansto.gov.au> rfulton@atom.ansto.gov.au (Roger Fulton) writes:


>    I'm looking for accurate 2D interpolation algorithms.
>    A bicubic algorithm I'm using (which is built in to IDL) is good,
>    but not quite good enough for my needs. It produces values
>    which are greater than any that were present before
>    interpolation.

Are you sure this is a problem? For example, if in 1-dim case you have
values  [1,2,3,3,2,1] at points  [0,1,2,3,4,5] then at  point 2.5 most
interpolation schemes would produce a value larger than 3.

>    Does anyone know of any other algorithm which may perform better
>	than bicubic ? 

It really depends on what "better" means. If the above condition is
your criterion, then in 1D case you would use linear interpolation,
but I'm not sure what is a good analogy in a 2D case.

--
Alex Zatsman, Analog Devices, Inc.,
Tel: (617) 461-3729, Fax: (617) 461-4241
alex.zatsman@analog.com

