[linux-audio-dev] Noise reduction with FFT

[james at dis-dot-dat.net]

On Thu, 06 Jan, 2005 at 11:29AM -0500, Lee Revell spake thus:
> On Thu, 2005-01-06 at 01:42 -0600, Spencer Russell wrote:
> > I've got this really noisy audio file I'm trying to clean up, and
> > I was thinking, it would be really cool if I could run a clip of
> > the file that was just the noise(it's a recording of a discussion
> > for a TV broadcast, so when no one's talking, it should be
> > silent) and have the program output an average frequency content,
> > in some sort of format that another program could take it as
> > input and create a filter that would filter out those
> > frequencies. It seems like brutefir would be able to do the
> > latter part, but is there a way to automatically generate the
> > filter definition from the frequency content of a file? Is this a
> > feasable method of noise reduction? If it seems like it could
> > work, but there isn't a program to do it, I would be interested
> > in writing it, if anyone has any input.
> 
> It certainly should work, because this is exactly how the NR plugin in
> Cool Edit Pro works.  Sound Forge has something similar.  I have used
> this to remove analog hiss from old Dead bootlegs.  No idea how to do it
> on Linux.
> 
> You should not need 2 programs, this should be as easy as select the
> noise, "NR -> Analyze", select entire .wav, "NR -> Go", or something.
> 
> Any decent .wav editor should do it.  All of them do on Windows.  If
> this really can't be done easily on Linux, that's discouraging, it means
> we have a LONG way to go.

Don't panic.  Audacity does it.
 
> Lee
> 
> 

-- 
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