/home/marsyas/marsyas/src/marsyas/ResampleBezier.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 "ResampleBezier.h"

using namespace std;
using namespace Marsyas;

ResampleBezier::ResampleBezier(mrs_string name):MarSystem("ResampleBezier", name)
{
    //Add any specific controls needed by ResampleBezier
    //(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();
}

ResampleBezier::ResampleBezier(const ResampleBezier& 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 


    //mrs_bool ctrl_tangentMode -   false:  (default)tangent at interpolation point is derived from the previous and immediately following sample; 
    //                              true:   tangents at each interpolation point are parallel to the axis along the indices of the samples
    //                                      which alows for smooth transition at frame endings, 
    //                                      maximum amplitude will be limited to the maximum prior to interpolation
    //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_tangentMode_ = getctrl("mrs_bool/tangentMode");
    ctrl_samplingRateAdjustmentMode_ = getctrl("mrs_bool/samplingRateAdjustmentMode");
    ctrl_stretch_ = getctrl("mrs_real/stretch");

}

ResampleBezier::~ResampleBezier()
{
}

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

void 
ResampleBezier::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/tangentMode", (mrs_bool)false , ctrl_tangentMode_);
    addctrl("mrs_real/stretch", 1.0 , ctrl_stretch_);
    setctrlState("mrs_real/stretch", true);
    setctrlState("mrs_bool/samplingRateAdjustmentMode",(mrs_bool)true);
    
}

void
ResampleBezier::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); 
    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, "ResampleBezier_"), NOUPDATE);
    
}

mrs_real 
ResampleBezier::interpolBezier(mrs_realvec px,mrs_real t)
{
    mrs_natural n = px.getSize();
    mrs_realvec q;
    q.create(n,n);
    
    for (mrs_natural i=0;i<n;++i)
    {
        q(i,0) = px(i);
    }

    //j - number of interpolation step
    //i - number of points
    for (mrs_natural j=1;j<n;j++)
    {
        for (mrs_natural i=0;i<n-j;++i)
        {
            q(i,j) = (1 - t) * q(i,j - 1) + t * q(i + 1,j - 1);
        }
    }
    return q(0,n-1);
}


void 
ResampleBezier::myProcess(realvec& in, realvec& out)
{   
    //cout << "-------------------------WORLD ENDING!!!" << endl;
    mrs_natural numb=inSamples_*3;  //cubic bezier curve:2 control points for each interpolation point
    mrs_realvec sx;
    mrs_realvec sy;
    mrs_realvec bx;
    mrs_realvec by;
    sx.create(inSamples_);
    sy.create(inSamples_);
    bx.create(numb);
    by.create(numb);

    mrs_realvec px;
    px.create(inSamples_);
    for(mrs_natural i=0;i<inSamples_;++i)
    {
        px(i)=i;
    }

    //#############chosen length parameterisation############
    mrs_realvec u2;
    u2.create(inSamples_);

    for (mrs_natural o=0;o<inObservations_;o++)
    {
        for (mrs_natural i=0;i<inSamples_;++i)
        {

            if (i!=inSamples_-1)
            {
            
                if (i!=0) 
                {
                    u2(i)=u2(i-1)+sqrt((px(i)-px(i+1))*(px(i)-px(i+1))+(in(o,i)-in(o,i+1))*(in(o,i)-in(o,i+1)));
                }
                else 
                {
                    u2(0)=0;
                }
            }
            else
            {
                u2(i)=u2(i-1)+sqrt((px(i)-px(0))*(px(i)-px(0))+(in(o,i)-in(o,0))*(in(o,i)-in(o,0)));
            }
        }
    

        mrs_natural foo=(mrs_natural)0;
        mrs_natural bar=(mrs_natural)0;

        mrs_real deltauk=(mrs_real)0.0;
        mrs_real deltaukm=(mrs_real)0.0;

        mrs_bool tangentMode=ctrl_tangentMode_->to<mrs_bool>();
        mrs_natural samplesout=getctrl("mrs_natural/onSamples")->to<mrs_natural>();
        for(mrs_natural k=0;k<inSamples_;k++)
        {   
            //indices for previous and next element with border management
            mrs_natural bla=k-1;
            if (bla<0)
            {
                bla=0;
            }
            mrs_natural blu=k+1;
            if (blu>inSamples_-1)
            {
                blu=inSamples_-1;
            }
            
            //indices for previous and next bezier points with border management 
            //this are the indizes of the control points that do not actually lie on the interpolation polynomial 
            //unlike each point with an index of 3*k
            foo=(3*k-1)%numb;
            if (foo<0) 
            {
                foo=foo+numb;
            }
            bar=(3*k+1)%numb;
            if (bar<0) 
            {
                bar=bar+numb;
            }
            
            if (k>=2)
            {
                deltauk=u2(k)-u2(k-1);
                deltaukm=u2(k-1)-u2(k-2);
            }
            else
            {
                deltauk=0.5;
                deltaukm=0.5;
            }
            if (tangentMode==(mrs_bool)true)
            {
                
                sx(k)=(px(blu)-px(bla))/(deltauk+deltaukm); //normalization for non equidistant parameterization
                sy(k)=(in(o,blu)-in(o,bla))/(deltauk+deltaukm); //normalization for non equidistant parameterization
                
                bx(foo)=px(k)-deltaukm*sx(k)/2.0;
                by(foo)=in(o,k)-deltaukm*sy(k)/2.0;
                
                bx(3*k)=px(k);
                by(3*k)=in(o,k);
            
                bx(bar)=px(k)+deltauk*sx(k)/2.0;
                by(bar)=in(o,k)+deltauk*sy(k)/2.0;
            }
            else
            {
                sx(k)=(px(blu)-px(bla))/(deltauk+deltaukm); 
                
                sy(k)=(in(o,blu)-in(o,bla))/(deltauk+deltaukm); 
                
                bx(foo)=px(k)-0.5*(px(k)-px(bla));
                
                by(foo)=in(o,k);
                
                bx(3*k)=px(k);
                by(3*k)=in(o,k);
                
                bx(bar)=px(k)+0.5*(px(blu)-px(k));
                by(bar)=in(o,k);
            }
        }
        //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_natural index=0;
        mrs_realvec ix;
        mrs_realvec yp;
        ix.create(4);
        yp.create(4);
        for(mrs_natural i=0;i<samplesout;++i)
        {
            mrs_real ra=offStart+i*ratio;
            while (index+1<ra)
            {
                index=index+1;
            }
            for(mrs_natural j=0;j<4;j++)
            {
                ix(j)=bx((3*index+j)%((int)inSamples_*3));
                yp(j)=by((3*index+j)%((int)inSamples_*3));
            }
            
            mrs_real difference=ra-index;
            out(o,i)=interpolBezier(yp, difference);
        }
    }

}

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