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From: "Rune Allnor" <allnor@tele.ntnu.no>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Dummies guide to DCT
Date: 16 Nov 2006 15:56:56 -0800
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James Turner skrev:
> sturlamolden wrote:
> >
> >
> >
> > James Turner wrote:
> >
> >> I was wondering if someone could explain to me the Discrete
> > Cosine
> >> Transform, in as simple as possible English.
> >
> > In the DCT the signal is decomposed into a sum of cosines, as
> > opposed
> > to the Discrete Fourier transform (DFT) where the signal is
> > decomposed
> > into a sum of sines and cosines.
> >
> >
>
>
> Thanks for the respone guys, but I think I need even more reading. I
> am lost at "the signal is decomposed into a sum of cosines". I don't
> understand what a sum of cosines is! Is there not a way of explaining
> DCT assuming that a person ONLY understands what a digital image is
> (i.e. a collection of pixels described using bits)? I'm talking
> simple so a kid could understand it kind of stuff!

Why do you expect anybody to be able to do that? The DCT is
usually taught in the 3rd or 4th year in university, after at least
two years priming with basic maths and some intro image
processing and DSP courses.

There is a reason why the DCT is not taught to kids.

Rune