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Mail Archives: djgpp/1999/09/06/10:54:27

From: Clemens Valens <c DOT valensNOxdSPAM AT mindless DOT com>
Subject: Re: FFT / spectrum analysis?
Newsgroups: comp.os.msdos.djgpp
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Date: Mon, 06 Sep 1999 07:38:33 -0700
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

What's the difficulty anyway? You seem to have all the 
building blocks already. Maybe this helps:

Repeat 
1. Fill an array with f.i. 256 samples (not too much, 
because the FFT will be too slow);
2. do an FFT on this array;
3. display the results. 

To get it running in real time you probably have to use two 
sample buffers, one to collect the new samples while you 
FFT and display the other. You simply swap the buffers when 
you're done.

But, using FFT's is not that obvious. Maybe you could just 
use some FIR's for the frequencies you want to display.

Clemens

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