filtering (signal processing)

[Erik de Castro Lopo]

William Park wrote:
> 
> Usual low-pass is done in frequency-domain.  

Sorry, that is just not true. 

> That is, do FFT, attenuate
> high frequencies, then do inverse FFT. 

This method is only used by those who don't understand time
domain filtering.

It looks like the original poster was looking for something
that works with Python. Unfortunately I am not aware of
any time domain filtering or filter design modules for 
Python. However, if the OP is willing to look a Octave:

    http://www.octave.org/

it should be able to fulfill all his needs.

Erik
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  Erik de Castro Lopo  nospam at mega-nerd.com (Yes it's valid)
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