[linux-audio-dev] Paper on dynamic range compression

[Steve Harris]

On Thu, Oct 05, 2006 at 05:04:07 +0100, Steve Harris wrote:
> On Thu, Oct 05, 2006 at 05:29:20 +0200, Alfons Adriaensen wrote:
> > On Thu, Oct 05, 2006 at 09:14:26AM -0500, Andres Cabrera wrote:
> > 
> > > Just to clarify the problem I'm encountering, here's a zoom in on the 
> > > processed wave, exactly at the point where gain reduction starts 
> > > occuring. This screenshot doesn't apply any of the methods proposed in 
> > > the paper, it shows the output of the plugin. This behavior occurs for 
> > > the Tap, SC1 and SC4 plugins in Ardour, Audacity and Rezound. All 
> > > processed files were saved at 32-bit floating point.
> > > 
> > > www.geminiflux.com/Tap-processed.jpg

The SC* plugins do the same as TAP (calculate the gain every 4 samples),
but I interpolate the gain values between each computation. The
attch/deacay times were slow enough in my testing that it was OK to do
that.

It would be trivial to change the plugins to caclulate every sample, but
at the time they were first released it made the plugin too expensive to
run many at once. Things may be better on current CPUs.

- Steve