server/plugins/PV_ThirdParty.cpp

   1 /*
   2         SuperCollider real time audio synthesis system
   3     Copyright (c) 2002 James McCartney. All rights reserved.
   4         http://www.audiosynth.com
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  19 */
  20
  21 //third party Phase Vocoder UGens
  22
  23
  24 #include "FFT_UGens.h"
  25
  26
  27 extern "C"
  28 {
  29         void PV_ConformalMap_Ctor(PV_Unit *unit);
  30         void PV_ConformalMap_next(PV_Unit *unit, int inNumSamples);
  31 }
  32
  33
  34 void PV_ConformalMap_Ctor(PV_Unit *unit)
  35 {
  36         SETCALC(PV_ConformalMap_next);
  37         ZOUT0(0) = ZIN0(0);
  38 }
  39
  40
  41 void PV_ConformalMap_next(PV_Unit *unit, int inNumSamples)
  42 {
  43         PV_GET_BUF
  44
  45         SCComplexBuf *p = ToComplexApx(buf);
  46
  47         float real2 = ZIN0(1);
  48         float imag2 = ZIN0(2);
  49
  50         for (int i=0; i<numbins; ++i) {
  51                 float real1 = p->bin[i].real;
  52                 float imag1 = p->bin[i].imag;
  53
  54                 //apply conformal map z-> z-a/(1-za*) where z is the existing complex number in the bin and a is defined by inputs 1 and 2
  55                 float numr= real1-real2;
  56                 float numi= imag1-imag2;
  57                 float denomr= 1.f - (real1*real2+imag1*imag2);
  58                 float denomi= (real1*imag2- real2*imag1);
  59
  60                 numr= numr*denomr+numi*denomi;
  61                 numi= numi*denomr-numr*denomi;
  62
  63                 //squared modulus
  64                 denomr= denomr*denomr+denomi*denomi;
  65
  66                 //avoid possible divide by zero
  67                 if(denomr<0.001f) denomr=0.001f;
  68                 denomr=1.f/denomr;
  69
  70                 p->bin[i].real = numr*denomr;
  71                 p->bin[i].imag = numi*denomr;
  72         }
  73
  74 }
  75
  76
  77 #define DefinePVUnit(name) \
  78         (*ft->fDefineUnit)(#name, sizeof(PV_Unit), (UnitCtorFunc)&name##_Ctor, 0, 0);
  79
  80
  81 //void initPV_ThirdParty(InterfaceTable *it);
  82 void initPV_ThirdParty(InterfaceTable *it)
  83 {
  84         DefinePVUnit(PV_ConformalMap);
  85 }
  86