/home/marsyas/marsyas/src/marsyas/ResampleSinc.cpp

/*
** Copyright (C) 1998-2010 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 "ResampleSinc.h"
#include "common.h"

using namespace std;
using namespace Marsyas;

ResampleSinc::ResampleSinc(mrs_string name):MarSystem("ResampleSinc", name)
{
    //Add any specific controls needed by ResampleSinc
    //(default controls all MarSystems should have
    //were already added by MarSystem::addControl(), 
    //called by :MarSystem(name) constructor).
    //If no specific controls are needed by a MarSystem
    //there is no need to implement and call this addControl()
    //method (see for e.g. Rms.cpp)
    addControls();
}

ResampleSinc::ResampleSinc(const ResampleSinc& a) : MarSystem(a)
{
    // For any MarControlPtr in a MarSystem 
    // it is necessary to perform this getctrl 
    // in the copy constructor in order for cloning to work 


//Controls:
    //mrs_bool ctrl_windowedMode    -   false:  apply sinc interpolation directly
    //                              true:   (default) use values of Kaiser Window and interpolate linearly between them if necessary
    //mrs_bool ctrl_samplingRateAdjustmentMode - adjust new resulting SamplingRate for following Marsystems
    //mrs_real stretch - desired stretch ratio (number of output samples = input number of samples*stretch)
    //mrs_real offStart - (default:0) offset from the start (towards the end) of the Samples (if only a part of the samples should be used to interpolate)
    //mrs_real offEnd - (default:0) offset from the end (towards the start) of the Samples (if only a part of the samples should be used to interpolate)


    ctrl_offStart_ = getctrl("mrs_real/offStart");
    ctrl_offEnd_ = getctrl("mrs_real/offEnd");
    ctrl_windowedMode_ = getctrl("mrs_bool/windowedMode");
    ctrl_samplingRateAdjustmentMode_ = getctrl("mrs_bool/samplingRateAdjustmentMode");
    ctrl_stretch_ = getctrl("mrs_real/stretch");

}

ResampleSinc::~ResampleSinc()
{
    
}

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

void 
ResampleSinc::addControls()
{
    //Add specific controls needed by this MarSystem.
    addctrl("mrs_real/offStart", 0.0, ctrl_offStart_);
    addctrl("mrs_real/offEnd", 0.0, ctrl_offEnd_);
    addctrl("mrs_bool/samplingRateAdjustmentMode", (mrs_bool)true , ctrl_samplingRateAdjustmentMode_);
    addctrl("mrs_bool/windowedMode", (mrs_bool)false , ctrl_windowedMode_);
    addctrl("mrs_real/stretch", 1.0 , ctrl_stretch_);
    setctrlState("mrs_real/stretch", true);
    setctrlState("mrs_bool/samplingRateAdjustmentMode",(mrs_bool)true);
    
}

void
ResampleSinc::myUpdate(MarControlPtr sender)
{
    MarSystem::myUpdate(sender);
    

    mrs_real alpha = ctrl_stretch_->to<mrs_real>();

    ctrl_onSamples_->setValue((mrs_natural) (alpha * ctrl_inSamples_->to<mrs_natural>()), NOUPDATE); 
    //cout << "updating: " << ctrl_inSamples_->to<mrs_natural>() << endl;
    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, "ResampleSinc_"), NOUPDATE);
    
}

mrs_real 
ResampleSinc::sinc(mrs_real t)
{
    mrs_real ret=0.0;
    if (t==0)
        ret=1.0;
    else
        ret=sin(t*PI)/(t*PI);
    return ret;
}

mrs_real 
ResampleSinc::window(mrs_real position)
{
    mrs_realvec y;
    y.create(11);

//    Kaiser Window beta=2, length 11
    y(0)=1;
    y(1)=1.393725584134;
    y(2)=1.749980639738;
    y(3)=2.033757714070;
    y(4)=2.21650903826;
    y(5)=2.279585302336;

//    Kaiser Window beta=1, length 13
//    y(0)=1;
//    y(1)=1.077860145694;
//    y(2)=1.143786491151;
//    y(3)=1.196474329913;
//    y(4)=1.234877004454;
//    y(5)=1.258229528804;
//    y(6)=1.266065877752;

//    Kaiser Window beta=2, length 13
//    y(0)=1.0;
//    y(1)=1.3297043679778717;
//    y(2)=1.6376481570588971;
//    y(3)=1.9029098945382872;
//    y(4)=2.1070523256224973;
//    y(5)=2.2356659845728475;
//    y(6)=2.2795853023360673;

    
    mrs_real divisor=2.279585302336;
    
    for (mrs_natural i=0;i<y.getSize();++i)
        
        if (i<=y.getSize()/2)
            y(i)=y(i)/divisor;
        else
            y(i)=y(y.getSize()-i-1);
    
    if ((position <-5) | (position > 5))
        return 0;
    
    mrs_natural index=0;
    while (index+1<5+position)
    {
        index=index+1;
    }
    mrs_real difference=5+position-index;
    return (1-difference)*y(index)+difference*y(index+1);
}


void 
ResampleSinc::myProcess(realvec& in, realvec& out)
{   
    
    for (mrs_natural o=0;o<inObservations_;o++)
    {
        
        mrs_bool windowedMode=ctrl_windowedMode_->to<mrs_bool>();
        mrs_natural samplesout=getctrl("mrs_natural/onSamples")->to<mrs_natural>();
        
        //endof for
        mrs_real offStart=ctrl_offStart_->to<mrs_real>();
        mrs_real offEnd=ctrl_offEnd_->to<mrs_real>();

        mrs_real ratio=(inSamples_-1-offStart-offEnd)/(mrs_real)(samplesout-1);
        mrs_realvec arrx;
        arrx.create(samplesout);
        mrs_realvec arr;
        arr.create(samplesout);
        mrs_natural count=0;
        for(mrs_natural i=0;i<samplesout;++i)
        {
            arrx(count)=offStart+i*ratio;
            count=count+1;
        }
                
        mrs_natural winlength=5;//maximum windowlength is also enforced by the window function
        for (mrs_natural ansinks=0;ansinks<inSamples_;ansinks++)
        {
            for (int i=0;i<samplesout;++i)
            {
                if (abs(arrx(i)-ansinks)<winlength)
                {
                    if (windowedMode)
                    {
                        arr(i)=arr(i)+in(o,ansinks)*sinc(arrx(i)-ansinks)*window(arrx(i)-ansinks);
                    }
                    else
                    {
                        arr(i)=arr(i)+in(o,ansinks)*sinc(arrx(i)-ansinks);
                    }
                }
            }
            
        }
        
        for (int i=0;i<samplesout;++i)
        {
            out(o,i)=arr(i);
        }

    }//ENDOF for observations

}

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