Re: [Alsa-user] multichannel multiband FFT-based equalizer - README

[fons a. <fon...@sk...>]

On Mon, Jan 02, 2006 at 04:52:42PM -0800, Bill Unruh wrote:

> Once you have made teh discrete sampling you have lost the original signal.
> It is gone. You cannot reconstruct it. 
> IF you assume that the original signal is frequency limited, then you may
> be able to reconstruct it.

Sigh. Of course it's assumed to be limited in frequency. Should I really
restate obvious preconditions each time ?


A frequency limited signal can be represented by and reconstructed from
a finite number of samples per time unit. (Shannon)

Dual:

A time limited spectrum can be represented by and reconstructed from
a finite number of samples per frequency unit.


I didn't invent any of this. Hundreds of thousands of engineers have been
capable of understanding it. I'll gladly admit it has taken me some time
to do the same. I'm sure you will be able to follow. Just think. Please.

-- 
FA