|| || || || || ||

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SearcherAroundLastPos.h

Go to the documentation of this file.

#ifndef Impala_Core_Tracking_SearcherAroundLastpos_h
#define Impala_Core_Tracking_SearcherAroundLastpos_h

#include "Core/Tracking/SearcherBase.h"

namespace Impala
{
namespace Core
{
namespace Tracking
{

class SearcherAroundLastPos : public SearcherBase
{
public:
    SearcherAroundLastPos()
    {
        mSampleSize = 300;
        mPosSigma = 20;
    }

    void
    SearchObject(Array::Array2dVec3Real64& image)
    {
        int i;
        double score;
        double bestScore = 1e100; //high, todo: get high value from standard library
        Point bestPos;
        Array::Array2dVec3Real64* temp =
            new Array::Array2dVec3Real64(mLastPos.size.x, mLastPos.size.y, 0, 0);
        for(i=0 ; i<mSampleSize ; i++)
        {
            double x,y,sqr;
            // take 2 random numbers with normal distribution
            do
            {
                do
                {
                    x = ((double)rand() / (double)RAND_MAX) * 2 - 1;
                    y = ((double)rand() / (double)RAND_MAX) * 2 - 1;
                    sqr = x*x + y*y;
                }
                while(sqr >=1.0 || sqr == 0);
                double fac = sqrt(-2.0*log(sqr)/sqr);

                x = (fac * x * mPosSigma) + mLastPos.translation.x;
                y = (fac * y * mPosSigma) + mLastPos.translation.y;
            }
            while(x<0 || y<0 || x+mLastPos.size.x >= image.CW() ||
                  y+mLastPos.size.y >= image.CH());

            //Sample search area at pos. If scale is used in the searcher, we
            //should just send an image to the object representation. Since the
            //representation might not use pixel data the representation is
            //responsible for interpreting the sample we provide it.
            Array::Pattern::PatSet(temp,&image, (int)x, (int)y, mLastPos.size.x,
                                   mLastPos.size.y, 0, 0);
            //get score
            score = mObject->Score(*temp,mLastPos);
            //if best
            if(score < bestScore)
            {
                bestPos.x = x;
                bestPos.y = y;
                bestScore = score;
            }
        }

        //now search around the found position for the best fit, because not all
        //neighbours are sampled
        int x,y;
        for(x=bestPos.x-3 ; x<=bestPos.x+3 ; x++)
        {
            for(y=bestPos.y-3 ; y<=bestPos.y+3 ; y++)
            {
                if(x>=0 && y>=0 && x+mLastPos.size.x < image.CW() &&
                   y+mLastPos.size.y < image.CH())
                {
                    Array::Pattern::PatSet(temp,&image, (int)x, (int)y,
                                           mLastPos.size.x, mLastPos.size.y, 0, 0);
                    score = mObject->Score(*temp,mLastPos);
                    if(score < bestScore)
                    {
                        bestPos.x = x;
                        bestPos.y = y;
                        bestScore = score;
                    }
                }
            }
        }
        delete temp;


        mSpeed.translation.x = bestPos.x - mLastPos.translation.x;
        mSpeed.translation.y = bestPos.y - mLastPos.translation.y;
        mLastPos.translation = bestPos;
    }

    void
    Reset(Array::Array2dVec3Real64& image, ObjectRepresentation& object,
          const Position& pos)
    {
        SearcherBase::Reset(image, object, pos);
    }

private:
    int mSampleSize;
    double mPosSigma; // in the future same for rotation and scale
    Position mSpeed;
};

} // namespace Tracking
} // namespace Core
} // namespace Impala

#endif //Impala_Core_Tracking_SearcherAroundLastpos_h

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