/home/marsyas/marsyas/src/marsyas/StereoSpectrumSources.cpp

/*
** Copyright (C) 1998-2007 George Tzanetakis <gtzan@cs.uvic.ca>
**  
** 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 "StereoSpectrumSources.h"
#include "Peaker.h"

using namespace std;
using namespace Marsyas;

StereoSpectrumSources::StereoSpectrumSources(mrs_string name):MarSystem("StereoSpectrumSources", name)
{
    panPeaker_ = new Peaker("panPeaker");
}

StereoSpectrumSources::StereoSpectrumSources(const StereoSpectrumSources& a):MarSystem(a)
{
    panPeaker_ = new Peaker("panPeaker");
}

StereoSpectrumSources::~StereoSpectrumSources()
{
    delete panPeaker_;
}

MarSystem* 
StereoSpectrumSources::clone() const 
{
    return new StereoSpectrumSources(*this);
}

void
StereoSpectrumSources::myUpdate(MarControlPtr sender)
{
    (void) sender;
    MRSDIAG("StereoSpectrumSources.cpp - StereoSpectrumSources:myUpdate");

    ctrl_onSamples_->setValue(ctrl_inSamples_, NOUPDATE);
    ctrl_onObservations_->setValue(1, NOUPDATE);
    ctrl_osrate_->setValue(ctrl_israte_, NOUPDATE);
    ctrl_onObsNames_->setValue("StereoSpectrumSources,", NOUPDATE);

    panPeaker_->updControl("mrs_natural/inSamples", inObservations_-1);
    panPeaker_->updControl("mrs_natural/inObservations", 1);
    panPeaker_->updControl("mrs_natural/peakStart", 0);
    panPeaker_->updControl("mrs_natural/peakEnd", inObservations_-2);
    panPeaker_->updControl("mrs_real/peakStrength", 1.0);
}

void 
StereoSpectrumSources::myProcess(realvec& in, realvec& out)
{
    mrs_natural t,o;
    for (t = 0; t < inSamples_; t++)
    {
        //start by sorting in non-descending order the panning values
        //of all spectrum bins of the current frame
        in.getCol(t, orderedPans_);
        orderedPans_.sort();

        //MATLAB_PUT(orderedPans_, "orderedPans");
        //MATLAB_EVAL("plot(orderedPans)");

        //calculate derivative, i.e changes of panning
        panChanges_.create(inObservations_-1);
        for(o=0; o<inObservations_-1; ++o)
            panChanges_(o) = orderedPans_(o+1)-orderedPans_(o);

        //MATLAB_PUT(panChanges_, "panChanges");
        //MATLAB_EVAL("plot(panChanges)");

        //look for peaks in pan changes, i.e. a good estimate of
        //the number of stereo sources in the signal
        panPeaks_.create(inObservations_-1);
        panPeaker_->process(panChanges_, panPeaks_);

        //MATLAB_PUT(panPeaks_, "panPeaks");
        //MATLAB_EVAL("plot(panPeaks)");

        out(0, t) = 0.0;
        for(o=0; o < inObservations_-1; ++o)
            out(0,t) += (panPeaks_(o) != 0.0);//peaks are the non-zero values in panPeaks_
        
        //cout << out(0,t) << endl;
        
        // other option for calculating this (pseudo-code):
        // if abs(running-average - current_value) > 0.3 * running_average
    }
}

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