/home/marsyas/marsyas/src/marsyas/PvFold.cpp

/*
** Copyright (C) 1998-2006 George Tzanetakis <gtzan@cs.uvic.ca>
**  
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
** 
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
** GNU General Public License for more details.
** 
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software 
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/

#include "PvFold.h"

using std::ostringstream;
using namespace Marsyas;

PvFold::PvFold(mrs_string name):MarSystem("PvFold",name)
{
  //type_ = "PvFold";
  //name_ = name;
  
    N_ = 0;
    Nw_ = 0;
    PNw_ = 0;
    PN_ = 0;

    addControls();
}

PvFold::PvFold(const PvFold& a):MarSystem(a) 
{
    N_ = 0;
    Nw_ = 0;
    PNw_ = 0;
    PN_ = 0;
    ctrl_rmsIn_ = getctrl("mrs_real/rmsIn");
}



PvFold::~PvFold()
{
}

MarSystem* 
PvFold::clone() const 
{
  return new PvFold(*this);
}


void 
PvFold::addControls()
{
  addctrl("mrs_natural/FFTSize", MRS_DEFAULT_SLICE_NSAMPLES);
  setctrlState("mrs_natural/FFTSize", true);
  addctrl("mrs_real/rmsIn", 0.0, ctrl_rmsIn_);
  n_ = 0;
}



void
PvFold::myUpdate(MarControlPtr sender)
{
    
  mrs_natural t;
  setctrl("mrs_natural/onSamples", getctrl("mrs_natural/FFTSize"));
  setctrl("mrs_natural/onObservations", (mrs_natural)1);
  setctrl("mrs_real/osrate", getctrl("mrs_real/israte"));  
  
  N_ = getctrl("mrs_natural/onSamples")->to<mrs_natural>();
  
  Nw_ = getctrl("mrs_natural/inSamples")->to<mrs_natural>();

  // create analysis window if necessary
  if ((Nw_ != PNw_)||(N_ != PN_))
  {
      n_ = -Nw_;
      awin_.stretch(Nw_);


      
      for (t=0; t < Nw_; t++)
      {
          awin_(t) = (mrs_real)(0.5 * (1 - cos(TWOPI * t/(Nw_-1))));
      }
      /* when Nw_ > N also apply interpolating (sinc) windows 
       * to ensure that window are 0 at increments of N (the 
       * FFT length) aways from the center of the analysis
       * window 
       */ 
      /* if (Nw_ > N_) 
      {
          
          mrs_real x;
          x = (mrs_real)(-(Nw_ -1) / 2.0);
          for (t=0; t < Nw_; t++, x += 1.0)
          {
              if (x != 0.0) 
                  awin_(t) *= N_ * sin (PI * x/N_) / (PI *x);
          }
      }
      */ 
      /* normalize window for unit gain */ 
      
      mrs_real sum = 0.0;
      for (t =0; t < Nw_; t++)
      {
          sum += awin_(t);
      }
      
      mrs_real afac = (mrs_real)(2.0/ sum);
      
      awin_ *= afac;
  }

  
  


  
  PNw_ = Nw_;
  PN_ = N_;
  
}

void 
PvFold::myProcess(realvec& in, realvec& out)
{

    mrs_natural t;
    
    for (t=0; t < Nw_; t++)
    {
        out(0,t) = in(0,t)*awin_(t);
        // rmsIn += in(0,t) * in(0,t);
    }
    // rmsIn /= Nw_;
    // rmsIn = sqrt(rmsIn);
    // ctrl_rmsIn_->setValue(rmsIn );
    
    
    // circular shift 
    int half_Nw_ = Nw_/2;
    mrs_real tmp;
    for (t=0; t < half_Nw_; t++) 
    {
        tmp = out(0,t);
        out(0,t) = out(0, t+half_Nw_);
        out(0,t+half_Nw_) = tmp;
    }
    

  
}






    

    

    

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