From: "Greg von Winckel" <gregvwDEL@mathDEL.unmDEL.edu>
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Newsgroups: comp.soft-sys.matlab
Subject: Re: Dummies guide to DCT
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Date: Thu, 16 Nov 2006 17:42:10 -0500
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James Turner wrote:
>
>
> Hi,
>
> I was wondering if someone could explain to me the Discrete Cosine
> Transform, in as simple as possible English. I have attempted to
> read many webpages and books on the transform but this is the first
> time I have ever touched upon watermarking and malipulating images,
> and I have no previous knowledge of ANY form of watermarking or
> manipulating images. I really can't get my head around the process
> of the DCT.
>
> Any form of explanation that I may understand over my other sources
> would be great (for example, I have tried reading <http://en.wikipedia.org/wiki/Discrete_cosine_transform>
> ut I just can't make sense of it).
>
> Many thanks,
>
> James
  

You might want to take a look at my code for transforming between
Chebyshev polynomials and pointspace values. It is effectively a DCT.

 <http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=4591&objectType=file>

HTH,

Greg