annotate src/Modules/BMM/ModulePZFC.h @ 10:d54efba7f09b

- Updated contact details and copyright lines to reflect actual copyright ownership
 (the University of Cambridge's intellectual property policy says that students own the
copyright on stuff they write unless there is a funding agreement saying otherwise)

// Copyright 2008-2010, Thomas Walters
//
// AIM-C: A C++ implementation of the Auditory Image Model
// http://www.acousticscale.org/AIMC
//
// 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 3 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, see <http://www.gnu.org/licenses/>.

/*! \file
 *  \brief Dick Lyon's Pole-Zero Filter Cascade - implemented in C++ by Tom
 *  Walters from the AIM-MAT module based on Dick Lyon's code.
 *
 *  \author Thomas Walters <[e-mail]>
 *  \date created 2008/02/05
 * \version \$Id: ModulePZFC.h 2 2010-02-02 12:59:50Z tcw $
 */

#ifndef _AIMC_MODULES_BMM_PZFC_H_
#define _AIMC_MODULES_BMM_PZFC_H_

#include <vector>

#include "Support/Module.h"
#include "Support/Parameters.h"
#include "Support/SignalBank.h"

namespace aimc {
using std::vector;
class ModulePZFC : public Module {
 public:
  explicit ModulePZFC(Parameters *pParam);
  virtual ~ModulePZFC();

  /*! \brief Process a buffer
   */
  virtual void Process(const SignalBank &input);

 private:
  /*! \brief Reset all internal state variables to their initial values
   */
  virtual void ResetInternal();

  /*! \brief Prepare the module
   *  \param input Input SignalBank
   *  \param output true on success false on failure
   */
  virtual bool InitializeInternal(const SignalBank &input);

  /*! \brief Set the filterbank parameters according to a fit matrix from Unoki
   *  and Lyon's fitting routine
   */
  bool SetPZBankCoeffsERBFitted();

  /*! \brief Sets the general filterbank coefficients
   */
  bool SetPZBankCoeffs();

  /*! \brief Automatic Gain Control
   */
  void AGCDampStep();

  /*! \brief Detector function - halfwave rectification etc. Used internally,
   *  but not applied to the output.
   */
  float DetectFun(float fIN);

  /*! \brief Minimum
   */
  inline float Minimum(float a, float b);

  int channel_count_;
  int buffer_length_;
  int agc_stage_count_;
  float sample_rate_;
  float last_input_;

  // Parameters
  // User-settable scalars
  float pole_damping_;
  float zero_damping_;
  float zero_factor_;
  float step_factor_;
  float bandwidth_over_cf_;
  float min_bandwidth_hz_;
  float agc_factor_;
  float cf_max_;
  float cf_min_;
  float mindamp_;
  float maxdamp_;
  bool do_agc_step_;

  // Internal Buffers
  // Initialised once
  vector<float> pole_dampings_;
  vector<float> agc_epsilons_;
  vector<float> agc_gains_;
  vector<float> pole_frequencies_;
  vector<float> za0_;
  vector<float> za1_;
  vector<float> za2_;
  vector<float> rmin_;
  vector<float> rmax_;
  vector<float> xmin_;
  vector<float> xmax_;

  // Modified by algorithm at each time step
  vector<float> detect_;
  vector<vector<float> > agc_state_;
  vector<float> state_1_;
  vector<float> state_2_;
  vector<float> previous_out_;
  vector<float> pole_damps_mod_;
  vector<float> inputs_;
};
}

#endif  // _AIMC_MODULES_BMM_PZFC_H_