annotate src/Modules/NAP/ModuleHCL.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 2007-2010, 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 Halfwave rectification, compression and lowpass filtering
 */

/* \author Thomas Walters <[e-mail]>
 * \date created 2007/03/07
 * \version \$Id: ModuleHCL.h 4 2010-02-03 18:44:58Z tcw $
 */

#ifndef _AIMC_MODULE_NAP_HCL_H_
#define _AIMC_MODULE_NAP_HCL_H_

#include <vector>

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

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

  virtual void Process(const SignalBank &input);

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

  virtual void ResetInternal();

  /*! \brief Do lowpass filtering?
   */
  bool do_lowpass_;

  /*! \brief Do log compression?
   */
  bool do_log_;

  /*! \brief Cutoff frequency for lowpass filter
   */
  float lowpass_cutoff_;

  /*! \brief Order of Lowpass Filter
   */
  int lowpass_order_;

  /*! \brief Internal record of the number of channels in the input
   */
  int channel_count_;

  /*! \brief Time constant corresponsing to the lowpass filter 
   *  cutoff freqency
   */
  float time_constant_;

  /*! \brief Lowpass filter state variables
   */
  float xn_;
  float yn_;
  vector<vector<float> > yns_;
};
}  // namespace aimc

#endif  // _AIMC_MODULE_NAP_HCL_H_