/home/marsyas/marsyas/src/marsyas/ResampleLinear.cpp

/*
** Copyright (C) 1998-2006 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 "ResampleLinear.h"

using namespace std;
using namespace Marsyas;

ResampleLinear::ResampleLinear(mrs_string name):MarSystem("ResampleLinear", name)
{
    addControls();
}

ResampleLinear::ResampleLinear(const ResampleLinear& a) : MarSystem(a)
{
    ctrl_stretch_ = getctrl("mrs_real/stretch");
    ctrl_samplingRateAdjustmentMode_ = getctrl("mrs_bool/samplingRateAdjustmentMode");
}


ResampleLinear::~ResampleLinear()
{
}

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

void
ResampleLinear::addControls()
{
    addctrl("mrs_real/stretch", 1.0, ctrl_stretch_);
    addctrl("mrs_bool/samplingRateAdjustmentMode", (mrs_bool)true , ctrl_samplingRateAdjustmentMode_);

    setctrlState("mrs_real/stretch", true);
    setctrlState("mrs_bool/samplingRateAdjustmentMode",(mrs_bool)true);
}

void
ResampleLinear::myUpdate(MarControlPtr sender)
{
    MarSystem::myUpdate(sender);
    MRSDIAG("ResampleLinear.cpp - ResampleLinear:myUpdate");
    mrs_real alpha = ctrl_stretch_->to<mrs_real>();
    ctrl_onSamples_->setValue((mrs_natural) (alpha * ctrl_inSamples_->to<mrs_natural>()), NOUPDATE);
    ctrl_onObservations_->setValue(ctrl_inObservations_->to<mrs_natural>());

    if (!(ctrl_samplingRateAdjustmentMode_->to<mrs_bool>()))
    {
        alpha=1.0;
    }

    ctrl_osrate_->setValue(ctrl_israte_->to<mrs_real>()*alpha);
    
    mrs_string inObsNames = ctrl_inObsNames_->to<mrs_string>();
    // Add prefix to the observation names.
    ctrl_onObsNames_->setValue(obsNamesAddPrefix(inObsNames, "ResampleLinear_"), NOUPDATE);

}

void
ResampleLinear::myProcess(realvec& in, realvec& out)
{
    mrs_real tp;
    mrs_natural tl, tr;
    mrs_real alpha = ctrl_stretch_->to<mrs_real>();
    mrs_natural o,t;
    
    
    for (o=0; o < onObservations_; o++) 
    {
        for (t = 0; t < onSamples_; t++)
        {
            tp = t / alpha;
            tl= (mrs_natural)tp;
            tr = tl + 1;
            if (tl<inSamples_)
            {
                out(o,t) = (tr-tp) * in(o,tl) + (tp-tl) * in(o,tr);
            }
            else // reflect on boundary
            {
                out(o,t) = in(o,inSamples_-1); //  alternative possibilities would include:
                
                //periodic on boundary:
                //out(o,t) = in(o,0);
                
                //zero pad on boundary:
                //out(o,t) == 0;
            }
        }
    }
}

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