// Copyright 2007, Thomas Scott Stillwell
// All rights reserved.
//
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//provided that the following conditions are met:
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desc:Subtractive Stereo Enhancer
//tags: processing stereo
//author: Stillwell

slider1:0<0,100,1>Effect (%)
slider2:0<0,20,0.1>Make-Up Gain (dB)

in_pin:left input
in_pin:right input
out_pin:left output
out_pin:right output

@init
  log2db = 8.6858896380650365530225783783321; // 20 / ln(10)
  db2log = 0.11512925464970228420089957273422; // ln(10) / 20 

@slider
  effect = slider1 * 0.01;
  gain = exp(slider2 * db2log);

@sample
  center = (spl0 + spl1) * 0.5;
  spl0 -= center * effect;
  spl1 -= center * effect;
  spl0 *= gain;
  spl1 *= gain;
