FFT_numrec.cxx

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/*
 * Copyright (c) 2001-2004 MUSIC TECHNOLOGY GROUP (MTG)
 *                         UNIVERSITAT POMPEU FABRA
 *
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */


#include "FFT_numrec.hxx"

#include "Assert.hxx"
#include "Audio.hxx"
#include "Spectrum.hxx"
#include "SpectrumConfig.hxx"
#include "CLAM_Math.hxx"
#include "ProcessingFactory.hxx"

extern "C" {
#include "numrecipes_fft.h"
}

namespace CLAM 
{

namespace Hidden
{
        static const char * metadata[] = {
                "key", "FFT_numrec",
                "category", "Analysis",
                "description", "FFT_numrec",
                0
        };
        static FactoryRegistrator<ProcessingFactory, FFT_numrec> reg = metadata;
}


        bool FFT_numrec::ConcreteConfigure(const ProcessingConfig& c)
        {
                FFT_base::ConcreteConfigure(c);
                if ( !isPowerOfTwo( mSize ) )
                {
                        AddConfigErrorMessage("Configure failed: Numerical Recipes FFT algorithm does not"
                                "accept non power of two buffers");

                        return false;
                }

                return true;
        }

        FFT_numrec::FFT_numrec()
        {
                Configure(FFTConfig());
        }

        FFT_numrec::FFT_numrec(const FFTConfig &c)
        { 
                Configure(c);
        };

        FFT_numrec::~FFT_numrec()
        {
        }

        bool FFT_numrec::Do()
        {
                mOutput.GetData().SetSize( mInput.GetSize()/2+1);
                bool toReturn = Do(mInput.GetAudio(), mOutput.GetData());
                mInput.Consume();
                mOutput.Produce();
                return toReturn;
        };

        bool FFT_numrec::Do(const Audio& in, Spectrum &out)
        {
                TData *inbuffer;

                CLAM_DEBUG_ASSERT(IsRunning(), "FFT_numrec: Do(): Not in execution mode");

                out.SetSpectralRange(in.GetSampleRate()/2);

                switch(mState) {
                case sComplex:
                        inbuffer = in.GetBuffer().GetPtr();
                        // Buffer dump. This is a kludge; the right way to do this
                        // is using a non-inplace version of realft (which would
                        // not reduce performance).
                        for (int i=0; i<mSize; i++)
                                fftbuffer[i]=inbuffer[i];
                        realft(fftbuffer-1, mSize, 1);
                        ToComplex(out);
                        break;
                case sComplexSync:
                        inbuffer = in.GetBuffer().GetPtr();
                        // Buffer dump. This is a kludge; the right way to do this
                        // is using a non-inplace version of realft (which would
                        // not reduce performance).
                        for (int i=0; i<mSize; i++)
                                fftbuffer[i]=inbuffer[i];
                        realft(fftbuffer-1, mSize, 1);
                        ToComplex(out);
                        out.SynchronizeTo(mComplexflags);
                        break;
                case sOther:
                        CheckTypes(in,out);
                        inbuffer = in.GetBuffer().GetPtr();
                        // Buffer dump. This is a kludge; the right way to do this
                        // is using a non-inplace version of realft (which would
                        // not reduce performance).
                        for (int i=0; i<mSize; i++)
                                fftbuffer[i]=inbuffer[i];
                        realft(fftbuffer-1, mSize, 1);
                        ToOther(out);
                        break;
                default:
                        CLAM_ASSERT(false, "FFT_numrec: Do(): Inconsistent state");
                }
        
                return true;

        }


        void FFT_numrec::ToComplex(Spectrum &out)
        {
                Array<Complex>* outbuffer;

                outbuffer = &out.GetComplexArray();             
                (*outbuffer)[0].SetReal(fftbuffer[0]);   // Real Values
                (*outbuffer)[0].SetImag(0);   // Real Values
                (*outbuffer)[mSize/2].SetReal(fftbuffer[1]);
                (*outbuffer)[mSize/2].SetImag(0);
                
                for (int i=1; i< mSize/2; i++) {
                        (*outbuffer)[i].SetReal(fftbuffer[2*i]);  
                        (*outbuffer)[i].SetImag(-fftbuffer[2*i+1]);
                }
                
                outbuffer->SetSize(mSize/2+1);
        }


};//namespace CLAM