tomwalters@282: // Copyright 2007-2010, Thomas Walters
tomwalters@268: //
tomwalters@268: // AIM-C: A C++ implementation of the Auditory Image Model
tomwalters@268: // http://www.acousticscale.org/AIMC
tomwalters@268: //
tomwalters@318: // Licensed under the Apache License, Version 2.0 (the "License");
tomwalters@318: // you may not use this file except in compliance with the License.
tomwalters@318: // You may obtain a copy of the License at
tomwalters@268: //
tomwalters@318: //     http://www.apache.org/licenses/LICENSE-2.0
tomwalters@268: //
tomwalters@318: // Unless required by applicable law or agreed to in writing, software
tomwalters@318: // distributed under the License is distributed on an "AS IS" BASIS,
tomwalters@318: // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
tomwalters@318: // See the License for the specific language governing permissions and
tomwalters@318: // limitations under the License.
tomwalters@268: 
tomwalters@268: /*!
tomwalters@268:  * \file
tomwalters@268:  * \brief Halfwave rectification, compression and lowpass filtering
tomwalters@268:  */
tomwalters@268: 
tomwalters@282: /* \author Thomas Walters <tom@acousticscale.org>
tomwalters@268:  * \date created 2007/03/07
tomwalters@296:  * \version \$Id$
tomwalters@268:  */
tomwalters@268: 
tomwalters@283: #ifndef AIMC_MODULES_NAP_HCL_H_
tomwalters@283: #define AIMC_MODULES_NAP_HCL_H_
tomwalters@268: 
tomwalters@268: #include <vector>
tomwalters@268: 
tomwalters@268: #include "Support/Module.h"
tomwalters@268: #include "Support/SignalBank.h"
tomwalters@268: 
tomwalters@268: namespace aimc {
tomwalters@268: using std::vector;
tomwalters@268: class ModuleHCL : public Module {
tomwalters@268:  public:
tomwalters@280:   explicit ModuleHCL(Parameters *parameters);
tomwalters@268:   virtual ~ModuleHCL();
tomwalters@268: 
tomwalters@268:   virtual void Process(const SignalBank &input);
tomwalters@268: 
tomwalters@268:  private:
tomwalters@268:   /*! \brief Prepare the module
tomwalters@268:    *  \param input Input signal bank
tomwalters@268:    *  \param output true on success false on failure
tomwalters@268:    */
tomwalters@268:   virtual bool InitializeInternal(const SignalBank &input);
tomwalters@268: 
tomwalters@275:   virtual void ResetInternal();
tomwalters@275: 
tomwalters@280:   /*! \brief Do lowpass filtering?
tomwalters@280:    */
tomwalters@268:   bool do_lowpass_;
tomwalters@268: 
tomwalters@280:   /*! \brief Do log compression?
tomwalters@280:    */
tomwalters@268:   bool do_log_;
tomwalters@268: 
tomwalters@280:   /*! \brief Cutoff frequency for lowpass filter
tomwalters@280:    */
tomwalters@268:   float lowpass_cutoff_;
tomwalters@268: 
tomwalters@280:   /*! \brief Order of Lowpass Filter
tomwalters@280:    */
tomwalters@268:   int lowpass_order_;
tomwalters@268: 
tomwalters@280:   /*! \brief Internal record of the number of channels in the input
tomwalters@280:    */
tomwalters@268:   int channel_count_;
tomwalters@268: 
tomwalters@280:   /*! \brief Time constant corresponsing to the lowpass filter 
tomwalters@280:    *  cutoff freqency
tomwalters@280:    */
tomwalters@268:   float time_constant_;
tomwalters@268: 
tomwalters@280:   /*! \brief Lowpass filter state variables
tomwalters@280:    */
tomwalters@268:   float xn_;
tomwalters@268:   float yn_;
tomwalters@268:   vector<vector<float> > yns_;
tomwalters@268: };
tomwalters@268: }  // namespace aimc
tomwalters@268: 
tomwalters@283: #endif  // AIMC_MODULES_NAP_HCL_H_