FormantShifter.h

Go to the documentation of this file.

/*  SPDX-License-Identifier: GPL-2.0-or-later */
/*!********************************************************************
 
  Audacity: A Digital Audio Editor
 
  FormantShifter.h
 
  A class for shifting the formants of a voice signal.
 
  Matthieu Hodgkinson
 
**********************************************************************/
#pragma once
 
#include "StaffPad/FourierTransform_pffft.h"
#include "StaffPad/SamplesFloat.h"
#include <complex>
#include <memory>
 
namespace staffpad::audio
{
class FourierTransform;
}
 
class FormantShifterLoggerInterface;
 
class FormantShifter
{
public:
   const double cutoffQuefrency;
 
   FormantShifter(
      int sampleRate, double cutoffQuefrency,
      FormantShifterLoggerInterface& logger);
 
   void Reset(size_t fftSize);
   void Reset();
 
   void Process(
      const float* powerSpectrum, std::complex<float>* spectrum, double factor);
 
private:
   const int mSampleRate;
   FormantShifterLoggerInterface& mLogger;
   std::unique_ptr<staffpad::audio::FourierTransform> mFft;
   staffpad::SamplesComplex mEnvelope;
   staffpad::SamplesReal mCepstrum;
   std::vector<float> mEnvelopeReal;
   std::vector<float> mWeights;
};