FreqShift.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 "FreqShift.hxx"
#include "ProcessingFactory.hxx"

namespace CLAM
{

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


bool FreqShift::Do(const Spectrum& in, Spectrum& out)
{

        if ( !mConfig.GetPreserveOuts() )
        {
                out = in; //TODO big cludge for streaming
        }

        //xamat: todo, we just hope the spectrum is in mag/phase format
        DataArray& iMagArray =  in.GetMagBuffer();
        DataArray& iPhaseArray = in.GetPhaseBuffer();
        TSize spectrumSize = in.GetSize();
        //I need to keep a copy of the magnitude array to guarantee inplace processing is possible
        mOMagArray.Resize(spectrumSize);
        mOMagArray.SetSize(spectrumSize);
        mOPhaseArray.Resize(spectrumSize);
        mOPhaseArray.SetSize(spectrumSize);
        
        //actually this is one over the spectral resolution, but it will be better for what I need afterwords
        TData spectralResolution = spectrumSize/in.GetSpectralRange();
        int amount = Round(mShiftAmount.GetLastValue() * spectralResolution);
        
        for(int i = 0; i<spectrumSize; i++)
        {
                if(i<amount)
                {
                        mOMagArray[i] = 0;
                        mOPhaseArray[i] = 0;
                }
                else if(i>spectrumSize+amount)
                {
                        mOMagArray[i] = 0;
                        mOPhaseArray[i] = 0;
                }
                else
                {
                        mOMagArray[i] = iMagArray[i-amount];
                        mOPhaseArray[i] = iPhaseArray[i-amount];
                }
        }
        out.SetMagBuffer(mOMagArray);
        out.SetPhaseBuffer(mOPhaseArray);
        return true;
}


}