 
////////////////////////////////////////////////////////////////////////
// This file is part of the SndObj library
//
// 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 
//
// Copyright (c)Victor Lazzarini, 1997-2004
// See License.txt for a disclaimer of all warranties
// and licensing information

/////////////////////////////////////////////////
// IFGram.cpp: Instant Freq Analysis class
//
//           Victor Lazzarini, 2003
/////////////////////////////////////////////////

#include "IFGram.h"

IFGram::IFGram(){
  m_diffwin = new float[m_fftsize];
  m_fftdiff = new float[m_fftsize];
  m_diffsig = new float[m_fftsize];
  m_factor = m_sr/TWOPI; 
  m_pdiff = new float[m_halfsize];
}


IFGram::IFGram(Table* window, SndObj* input, float scale,
	       int fftsize, int hopsize, float sr)
  :PVA(window, input, scale, fftsize, hopsize, sr)
{
  m_diffwin = new float[m_fftsize];
  m_fftdiff = new float[m_fftsize];
  m_diffsig = new float[m_fftsize];
  m_pdiff = new float[m_halfsize];
  for(int i=0; i<m_fftsize; i++)
    m_diffwin[i] = m_table->Lookup(i) - m_table->Lookup(i+1);
  m_factor = m_sr/TWOPI;

}


IFGram::~IFGram(){
  delete[] m_diffwin;
  delete[] m_fftdiff;
  delete[] m_diffsig;
}


int
IFGram::Set(char* mess, float value){

  switch(FindMsg(mess)){

  case 22:
    SetFFTSize((int) value);
    return 1;
	
  default:
    return	PVA::Set(mess, value);

  }
}

int
IFGram::Connect(char* mess, void* input){

  int i;

  switch(FindMsg(mess)){

  case 24:
    SetWindow((Table *) input);
    for(i=0; i<m_fftsize; i++)
      m_diffwin[i] = m_table->Lookup(i) - m_table->Lookup(i+1);
    return 1;
	
  default:
    return	PVA::Connect(mess,input);

  }
}

void
IFGram::SetFFTSize(int fftsize){

  FFT::SetFFTSize(fftsize);

  delete[] m_diffwin;
  delete[] m_fftdiff;
  delete[] m_phases;

  m_factor = m_sr*TWOPI/m_fftsize;
  m_diffwin = new float[m_fftsize];
  m_fftdiff = new float[m_fftsize];
  m_phases = new float[m_halfsize];

  for(int i=0; i<m_fftsize; i++)
    m_diffwin[i] = m_table->Lookup(i) - m_table->Lookup(i+1);

}

void
IFGram::IFAnalysis(float* signal){

  double powerspec, da,db, a, b, ph,d; 
  int i2, i;

  for(i=0; i<m_fftsize; i++){
    m_diffsig[i] = signal[i]*m_diffwin[i];
    signal[i] = signal[i]*m_table->Lookup(i);
  }




  float tmp1, tmp2;
  for(i=0; i<m_halfsize; i++){
    tmp1 = m_diffsig[i+m_halfsize];
    tmp2 = m_diffsig[i];
    m_diffsig[i] = tmp1;
    m_diffsig[i+m_halfsize] = tmp2;

    tmp1 = signal[i+m_halfsize];
    tmp2 = signal[i];
    signal[i] = tmp1;
    signal[i+m_halfsize] = tmp2;

  }


  rfftw_one(m_plan, signal, m_ffttmp);
  rfftw_one(m_plan, m_diffsig, m_fftdiff);


  m_output[0] = m_ffttmp[0]/m_norm;
  m_output[1] = m_ffttmp[m_halfsize]/m_norm;

 
  for(i=2; i<m_fftsize; i+=2){

    i2 = i/2;
    a = m_ffttmp[i2]/m_norm;
    b = m_ffttmp[m_fftsize-(i2)]/m_norm;
    da = m_fftdiff[i2]/m_norm;
    db = m_fftdiff[m_fftsize-(i2)]/m_norm;
    powerspec = a*a+b*b;
	
    if((m_output[i] = (float)sqrt(powerspec)) != 0.f){
      m_output[i+1] = ((a*db - b*da)/powerspec)*m_factor + i2*m_fund;
      ph = (float) atan2(b, a);	
      d = ph - m_phases[i2];
      while(d > PI) d -= TWOPI;
      while(d < -PI) d += TWOPI;
      m_phases[i2] += d;
	
		 

    }
    else {
      m_output[i+1] = i2*m_fund;
      m_phases[i2] = 0.f ;
    }
  }

}


short
IFGram::DoProcess(){

  if(!m_error){
    if(m_input){
      if(m_enable){
	int i; float sig = 0.f;
	for(m_vecpos = 0; m_vecpos < m_hopsize; m_vecpos++) {
	  // signal input
	  sig = m_input->Output(m_vecpos);		
	  // distribute to the signal input frames
	  // according to a time pointer (kept by counter[n])
	  for(i=0;i < m_frames; i++){
	    m_sigframe[i][m_counter[i]]= (float) sig; 
	    m_counter[i]++;		   
	  } 
	}
	// every vecsize samples
	// set the current fftframe to be transformed
	m_cur--; if(m_cur<0) m_cur = m_frames-1;  
 
	// instant frequency analysis
	IFAnalysis(m_sigframe[m_cur]);
	// zero the current fftframe time pointer


	m_counter[m_cur] = 0;
	return 1;

      } else { // if disabled, reset the fftframes
	for(m_vecpos =0; m_vecpos < m_hopsize; m_vecpos++)
	  m_output[m_vecpos] = 0.f;
	return 1;
      }

    } else {
      m_error = 3;
      return 0;
    }
  }
  else 
    return 0;
}

