ian@0: //  Copyright 2011, Ian Hobson.
ian@0: //
ian@0: //  This file is part of gpsynth.
ian@0: //
ian@0: //  gpsynth is free software: you can redistribute it and/or modify
ian@0: //  it under the terms of the GNU General Public License as published by
ian@0: //  the Free Software Foundation, either version 3 of the License, or
ian@0: //  (at your option) any later version.
ian@0: //
ian@0: //  gpsynth is distributed in the hope that it will be useful,
ian@0: //  but WITHOUT ANY WARRANTY; without even the implied warranty of
ian@0: //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
ian@0: //  GNU General Public License for more details.
ian@0: //
ian@0: //  You should have received a copy of the GNU General Public License
ian@0: //  along with gpsynth in the file COPYING. 
ian@0: //  If not, see http://www.gnu.org/licenses/.
ian@0: 
ian@0: // MFCCAnalyzer - extracts MFCCs from a provided magnitude spectrum
ian@0: 
ian@0: #pragma once
ian@0: 
ian@0: #include "fftw3.h"
ian@0: 
ian@0: #include <vector>
ian@0: 
ian@0: namespace dsp {
ian@0: 
ian@0: class MFCCAnalyzer {  
ian@0:   fftw_plan dct_plan_;
ian@0:   int frame_size_;
ian@0:   double sample_rate_;
ian@0:   double frequency_min_;
ian@0:   double frequency_max_;
ian@0:   std::vector< std::vector<double> > mel_filters_;
ian@0:   int mel_bands_;
ian@0:   int number_of_mfccs_;
ian@0:   std::vector<double> mfccs_;
ian@0:   double* mel_bands_dct_in_;
ian@0:   double* mel_bands_dct_out_;
ian@0:   
ian@0: public:
ian@0:   MFCCAnalyzer(int frame_size,
ian@0:                int mel_bands,
ian@0:                int number_of_mfccs,
ian@0:                double frequency_min,
ian@0:                double frequency_max);
ian@0:   
ian@0:   ~MFCCAnalyzer();
ian@0:   
ian@0:   void SetSampleRate(double sample_rate);
ian@0:   
ian@0:   // extracts mfccs from a magnitude spectrum
ian@0:   const std::vector<double>& ExtractMFCCS(const std::vector<double>& spectrum);
ian@0:   
ian@0: private:
ian@0:   void InitializeMelDCT();
ian@0:   void InitializeFilters();  
ian@0: };
ian@0: 
ian@0: } // dsp namespace