vpMomentObject.cpp

/****************************************************************************
 *
 * $Id: vpMomentObject.cpp 4056 2013-01-05 13:04:42Z fspindle $
 *
 * This file is part of the ViSP software.
 * Copyright (C) 2005 - 2013 by INRIA. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * ("GPL") version 2 as published by the Free Software Foundation.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact INRIA about acquiring a ViSP Professional
 * Edition License.
 *
 * See http://www.irisa.fr/lagadic/visp/visp.html for more information.
 *
 * This software was developed at:
 * INRIA Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 * http://www.irisa.fr/lagadic
 *
 * If you have questions regarding the use of this file, please contact
 * INRIA at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 *
 * Description:
 * Object input structure used by moments.
 *
 * Authors:
 * Filip Novotny
 *
 *****************************************************************************/

#include <visp/vpMomentBasic.h>
#include <visp/vpMomentObject.h>
#include <visp/vpCameraParameters.h>
#include <visp/vpPixelMeterConversion.h>
#include <visp/vpConfig.h>
#include <cmath>
#include <limits>
#ifdef VISP_HAVE_OPENMP
#include <omp.h>
#endif
#include <cassert>

double vpMomentObject::calc_mom_polygon(unsigned int p, unsigned int q, const std::vector<vpPoint>& points){
    unsigned int i,k,l;
    double den,mom,s;
    double x_k;
    double x_p_k;
    double y_l;
    double y_q_l;

    den = static_cast<double>( (p+q+2)*(p+q+1)*vpMath::comb(p+q,p) );

    mom = 0.0;
    for (i=1;i<=points.size()-1;i++)
    {
      s = 0.0;
        x_k=1;
      for (k=0;k<=p;k++)
      {
        y_l=1;
        x_p_k = pow(points[i-1].get_x(), (int)(p-k));
        for (l=0;l<=q;l++)
        {
            y_q_l=pow(points[i-1].get_y(), (int)(q-l));

          s += static_cast<double>(
            vpMath::comb(k+l,l)
            *vpMath::comb(p+q-k-l,q-l)
            *x_k
            *x_p_k
            *y_l
            *y_q_l );

            y_l*=points[i].get_y();

        }
        x_k*=points[i].get_x();

      }

      s *= ((points[i-1].get_x())*(points[i].get_y())-(points[i].get_x())*(points[i-1].get_y()));
      mom += s;
    }
    mom /= den;
    return(mom);
}

void vpMomentObject::cacheValues(std::vector<double>& cache,double x, double y){
    cache[0]=1;

    for(register unsigned int i=1;i<order;i++)
        cache[i]=cache[i-1]*x;

    for(register unsigned int j=order;j<order*order;j+=order)
        cache[j]=cache[j-order]*y;

    for(register unsigned int j=1;j<order;j++){
        for(register unsigned int i=1;i<order-j;i++){
            cache[j*order+i] = cache[j*order]*cache[i];
        }
    }
}

void vpMomentObject::fromVector(std::vector<vpPoint>& points){
    if(type==vpMomentObject::DENSE_POLYGON){
        if(
                std::abs(points.rbegin()->get_x()-points.begin()->get_x())>std::numeric_limits<double>::epsilon() ||
                std::abs(points.rbegin()->get_y()-points.begin()->get_y())>std::numeric_limits<double>::epsilon()
                ){
            points.resize(points.size()+1);
            points[points.size()-1] = points[0];
        }
        for(register unsigned int j=0;j<order*order;j++){
            values[j]=calc_mom_polygon(j%order,j/order,points);
        }
    }else{
      std::vector<double> cache(order*order,0.);
        values.assign(order*order,0);
        for(register unsigned int i=0;i<points.size();i++){
            cacheValues(cache,points[i].get_x(),points[i].get_y());
            for(register unsigned int j=0;j<order;j++){
                for(register unsigned int k=0;k<order-j;k++){
                    values[j*order+k]+=cache[j*order+k];
                }
            }
        }
    }
}

void vpMomentObject::fromImage(const vpImage<unsigned char>& image, unsigned char threshold, const vpCameraParameters& cam){
#ifdef VISP_HAVE_OPENMP    
  #pragma omp parallel shared(threshold)
  {        
    std::vector<double> curvals(order*order); 
    curvals.assign(order*order,0.);
    unsigned int i_, j_;

    #pragma omp for nowait//automatically organize loop counter between threads
    for(int i=0;i<(int)image.getCols();i++){
      for(int j=0;j<(int)image.getRows();j++){
        i_ = static_cast<unsigned int>(i);
        j_ = static_cast<unsigned int>(j);
        if(image[j_][i_]>threshold){
          double x=0;
          double y=0;
          vpPixelMeterConversion::convertPoint(cam,i_,j_,x,y);

          double xval=1.;
          double yval=1.;
          for(register unsigned int k=0;k<order;k++){            
            xval=1.;
            for(register unsigned int l=0;l<order-k;l++){
              curvals[(k*order+l)]+=(xval*yval);
              xval*=x;
            }
            yval*=y;
          }          
        }
      }
    }    
    
    #pragma omp master //only set this variable in master thread
    {      
      values.assign(order*order, 0.);      
    }

    #pragma omp barrier
    
    for(register unsigned int k=0;k<order;k++){    
      for(register unsigned int l=0;l<order-k;l++){
        #pragma omp atomic
        values[k*order+l]+= curvals[k*order+l];
      }
    }
    
  }    
  
#else
  std::vector<double> cache(order*order,0.);
    values.assign(order*order,0);
    for(register unsigned int i=0;i<image.getCols();i++){
        for(register unsigned int j=0;j<image.getRows();j++){
            if(image[j][i]>threshold){
                double x=0;
                double y=0;
                vpPixelMeterConversion::convertPoint(cam,i,j,x,y);
                cacheValues(cache,x,y);
                for(register unsigned int k=0;k<order;k++){
                    for(register unsigned int l=0;l<order-k;l++){
                        values[k*order+l]+=cache[k*order+l];
                    }
                }
            }
        }
    }
#endif
}



vpMomentObject::vpMomentObject(unsigned int order) : order(order+1),type(DENSE_FULL_OBJECT){
    values.resize((order+1)*(order+1)*12);
    values.assign((order+1)*(order+1)*12,0);
}

std::vector<double>& vpMomentObject::get() {
    return values;

}

double vpMomentObject::get(unsigned int i, unsigned int j) const {
    assert(i+j<=getOrder());
    if(i+j>=order) throw vpException(vpException::badValue,"The requested value has not been computed, you should specify a higher order.");

    return values[j*order+i];
}

std::ostream & operator<<(std::ostream & os, const vpMomentObject& m){
    for(unsigned int i = 0;i<m.values.size();i++){

        if(i%(m.order)==0)
          os << std::endl;

        if((i%(m.order)+i/(m.order))<m.order)
            os << m.values[i] ;
        else
            os << "x";

        os  << "\t";

    }

    return os;
}