[SciPy-user] Low pass filter design and usage

[Lev Givon]

Received from Joseph Kardamis (RIT Student) on Thu, Jun 15, 2006 at 10:57:27AM EDT:
> 
> I need help in creating a low pass filter; I have very little
> experience in digital signal processing, if any. The context of the
> lowpass filter is as such: an audio signal is split into an array of
> subband signals attuned to particular frequencies.  These subband
> signals are then processed with full-wave compression, half-wave
> rectification, and lowpass filtering.  It seems that the
> scipy.signal module should have what I need to perform lowpass
> filtering, but my lack of knowledge in DSP is making it difficult to
> know what I'm doing or where even to start.
> 
> For each band, I know the center frequency of the band, and the
> lowpass filtering occurs at twice the center frequency.
> 
> Any help would be greatly appreciated.
> 
> Cheers,
> -Joe

Mathworks' documentation for Matlab's Signal Processing Toolbox is
a good starting point; it contains a number of examples that can be
recoded in Python using the DSP functions in scipy.signal:

http://www.mathworks.com/access/helpdesk/help/toolbox/signal/

							L.G.