view src/CAR.cpp @ 496:5a5fc3a6051b carfac_cpp

* SUGGESTED re-factor of the FIR_coeffs calls (old code remains in commented out form for easy comparison).

* Minor changes to CARFAC and IHC corresponding to MATLAB refactoring

#include "CAR.h"
#include "CARFAC_common.h"
#include "CARFAC.h"
#include <cmath>

CAR_coefficients::CAR_coefficients(CAR_parameters* car_params, float fs,
                                   FloatArray pole_freqs){

  float f = pow(car_params->zero_ratio_, 2) + 1;

  // TODO: dirty FloatArray initialization.
  r1_coeffs_= pole_freqs;
  a0_coeffs_= pole_freqs;
  c0_coeffs_= pole_freqs;
  h_coeffs_= pole_freqs;
  g0_coeffs_= pole_freqs;
  zr_coeffs_= pole_freqs;

  FloatArray theta = pole_freqs;

  float min_zeta_mod;
  float x;
  float ff = car_params->high_f_damping_compression_;

  // TODO: temp loop until we get eigen in  (or we just leave it like this)
  for(float i=0; i<pole_freqs.size(); i++){
      theta[i] *= (2*kPi*fs); // scalar mult.
      c0_coeffs_[i] = sin(theta[i]);
      a0_coeffs_[i] = cos(theta[i]);

      x = theta[i]/kPi;
      zr_coeffs_[i] = kPi * (x - ff * x*x*x);

      min_zeta_mod = (car_params->min_zeta_ + 0.25 * (CARFAC::ERB_Hz(
                      pole_freqs[i], car_params->erb_break_freq_,
                      car_params->erb_q_) / pole_freqs[i]
                     - car_params->min_zeta_));

      r1_coeffs_[i] = 1-zr_coeffs_[i]*min_zeta_mod;

      h_coeffs_[i] = c0_coeffs_[i] * f;

      //TODO: g0_coeffs_ calculated here for now. Let's talk about this, need
      // to see the whole picture of what makes sense.
      // Related: I believe CAR, IHC and AGC classes would be beneficial!
      float tmp = 1 - 2*r1_coeffs_[i]*a0_coeffs_[i] + r1_coeffs_[i]*r1_coeffs_[i];
      g0_coeffs_[i] = tmp / ( tmp + h_coeffs_[i]*r1_coeffs_[i]*c0_coeffs_[i]);
  }

}

CAR_coefficients::~CAR_coefficients(){
  // TODO Auto-generated destructor stub
}