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HxNgbNonMaxSuppression2d.h

/*
 *  Copyright (c) 1999, University of Amsterdam, The Netherlands.
 *  All rights reserved.
 *
 *  Author(s):
 *  Edo Poll                (poll@wins.uva.nl)
 */

#ifndef HxNgbNonMaxSuppression2d_h
#define HxNgbNonMaxSuppression2d_h

#include "HxClassName.h"
#include "HxSizes.h"
#include "HxNgbOpCategory.h"
#include "HxCnum.h"
#include "HxTagList.h"

template<class ArithT>
class HxNgbNonMaxSuppression2d
{
public:

    typedef HxNgbCnumTag        IteratorCategory;

    typedef HxNgb1PhaseTag      PhaseCategory;

    typedef HxNgbTransInVarTag  TransVarianceCategory;

    typedef HxCnum          CnumType;

                            HxNgbNonMaxSuppression2d(HxTagList& tags);
                            ~HxNgbNonMaxSuppression2d();

    HxSizes                 size();

    CnumType                begin();
    CnumType&               end();

    void                    init(const ArithT& value);
    void                    next(int x, int y, const ArithT& value);
    const ArithT&           result() const;

    static HxString         className();

private:
    HxCoord*                _coords;
    ArithT                  _resultPix;
    const ArithT            _nullPix;
    double                  _resultMag;
    bool                    _suppressed;
    static HxCoord          _coordPairs[12];
    CnumType                _end;
};

template<class ArithT>
inline TYPENAME HxNgbNonMaxSuppression2d<ArithT>::CnumType
HxNgbNonMaxSuppression2d<ArithT>::begin()
{
    return CnumType(&_coords[0]);
}

template<class ArithT>
inline TYPENAME HxNgbNonMaxSuppression2d<ArithT>::CnumType&
HxNgbNonMaxSuppression2d<ArithT>::end()
{
    return _end;
}

#include "HxBreakPoint.h"

template<class ArithT>
inline void
HxNgbNonMaxSuppression2d<ArithT>::init(const ArithT& v)
{
    HxBreakPoint();
    static const double tan22_5 = 0.41421356;
    static const double tan67_5 = 2.41421356;

    double x(v.x()), y(v.y());
    _resultPix = v;
    _resultMag = x*x+y*y;
    _suppressed = false;

    if (x != 0) {
        double rc = y/x;
        double frc = fabs(rc);
        int i = (frc < tan22_5) ? 0 : ( (frc < tan67_5) ? 1 : 2 );
        if (rc < 0)
            i += 3;
        _coords = &_coordPairs[i<<1];
    } else {
        _coords = &_coordPairs[4];
    }
    _end = &_coords[2];
}

template<class ArithT>
inline HxString
HxNgbNonMaxSuppression2d<ArithT>::className()
{
    static HxString s("nonMaxSuppression");
    return s;
}

template<class ArithT>
inline void
HxNgbNonMaxSuppression2d<ArithT>::next(int, int, const ArithT& v)
{
    if ((v.x()*v.x() + v.y()*v.y()) > _resultMag)
        _suppressed = true;
}

template<class ArithT>
inline HxSizes
HxNgbNonMaxSuppression2d<ArithT>::size()
{
    return HxSizes(3, 3, 1);
}

template<class ArithT>
inline const ArithT&
HxNgbNonMaxSuppression2d<ArithT>::result() const
{
    return _suppressed ? _nullPix : _resultPix;
}

#ifdef INC_TEMPLATE_SRC
#include "HxNgbNonMaxSuppression2d.c"
#endif

#endif

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