Re: noisered vs Audacity's noise removal filter

[Eric Wong <normalperson@yhbt.net>]

Eric Wong <normalperson@yhbt.net> wrote:
> Daniel Jensen <jensend@iname.com> wrote:
> > Obviously since Audacity's filter is GPL'd  while SoX's effects are 
> > LGPL'd, code can't be shared. (Even if SoX decided that this could go 
> > under the GPL, since Audacity's filter is in WxWidgets-heavy C++ this 
> > wouldn't help much.) I know very little about how clean-room one has to 
> > be in reimplementing their ideas to avoid the result becoming a 
> > derivative work.
> 
> I suggest writing a standalone LADSPA or lv2 plugin.  This way the
> filter can be useful to different programs.

Did you ever get around to doing this as a plugin? :)

Two years passed, I barely touched audio editing in that time,
but today I used noisered for the first time.

I have a recording made with excessively low levels
(around -30dB Pk, -57dB RMS); yikes.

So far, I've only found some quiet 100ms sections to make a noise
profile with (due to people moving/talking around me).  At first, the
result was littered with nasty artifacts with the default noisered
"amount" parameter (0.5).

However, I found the results are pretty good with an "amount" value set
to zero.  Using a >0 amount seems to introduce unpleasant artifacts.

I'll try to get a cleaner "silent" sample to noise profile with
(recording a new silent track may be necessary).  Most of the noise I'm
trying to reduce is from my recording gear and mics.  The blessing in
that is it ought to be easy to make a good profile track once I get
myself into a quiet room.

Hopefully I can avoid doing any more coding if I find a better sample to
noiseprof with, since the artifacts in my current work-in-progress track
are barely noticeable.

But if push comes to shove, I'll see if I can improve the sox
effect or port the Audacity one to LADSPA...

> I've also made patches which improve LADSPA support in SoX:
> https://sourceforge.net/tracker/?func=detail&atid=310706&aid=3534109&group_id=10706

Applied in 14.4.2rc1 \o/

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