Re: Query DCT and DFT

MJ wrote:

I have some very basic doubt about dct and dft.
The DCT is very commonly used in Image Processing for compression.
I want to know where else we can use DCT predominantly
what is the diff betweeb DCT AND DFT. can I achieve the same
compression with DFT as DCT. wht are the adavatages of each DCT nad DFT

The DCT is a transformation from the real domain into the real domain. DFT creates complex coefficients with reflection symmetry for real input data, and thus a bit more care has to be taken. Otherwise, from a mathematical p.o.v., the differences are really minor. DCT output is just a suitable linear combination of the complex DFT output such that one sees real numbers again.

So long,
	Thomas
.

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