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/** \file     Mv.h
    \brief    motion vector class (header)
*/

#ifndef __MV__
#define __MV__

#include "CommonDef.h"

//! \ingroup CommonLib
//! \{

// ====================================================================================================================
// Class definition
// ====================================================================================================================

enum MvPrecision
{
  MV_PRECISION_4PEL     = 0,      // 4-pel
  MV_PRECISION_INT      = 2,      // 1-pel, shift 2 bits from 4-pel
  MV_PRECISION_HALF     = 3,      // 1/2-pel
  MV_PRECISION_QUARTER  = 4,      // 1/4-pel (the precision of regular MV difference signaling), shift 4 bits from 4-pel
  MV_PRECISION_SIXTEENTH = 6,     // 1/16-pel (the precision of internal MV), shift 6 bits from 4-pel
  MV_PRECISION_INTERNAL = 2 + MV_FRACTIONAL_BITS_INTERNAL,
};

/// basic motion vector class
class Mv
{
private:
  static const MvPrecision m_amvrPrecision[4];
  static const MvPrecision m_amvrPrecAffine[3];
  static const MvPrecision m_amvrPrecIbc[3];

  static const int mvClipPeriod = (1 << MV_BITS);
  static const int halMvClipPeriod = (1 << (MV_BITS - 1));

public:
  int   hor;     ///< horizontal component of motion vector
  int   ver;     ///< vertical component of motion vector

  // ------------------------------------------------------------------------------------------------------------------
  // constructors
  // ------------------------------------------------------------------------------------------------------------------

  Mv(                    ) : hor( 0    ), ver( 0    ) {}
  Mv( int iHor, int iVer ) : hor( iHor ), ver( iVer ) {}

  // ------------------------------------------------------------------------------------------------------------------
  // set
  // ------------------------------------------------------------------------------------------------------------------

  void  set       ( int iHor, int iVer)     { hor = iHor;  ver = iVer; }
  void  setHor    ( int i )                 { hor = i;                 }
  void  setVer    ( int i )                 { ver = i;                 }
  void  setZero   ()                        { hor = ver = 0;           }

  // ------------------------------------------------------------------------------------------------------------------
  // get
  // ------------------------------------------------------------------------------------------------------------------

  int   getHor    () const { return hor;          }
  int   getVer    () const { return ver;          }
  int   getAbsHor () const { return abs( hor );   }
  int   getAbsVer () const { return abs( ver );   }

  // ------------------------------------------------------------------------------------------------------------------
  // operations
  // ------------------------------------------------------------------------------------------------------------------

  const Mv& operator += (const Mv& _rcMv)
  {
    hor += _rcMv.hor;
    ver += _rcMv.ver;

    return  *this;
  }

  const Mv& operator-= (const Mv& _rcMv)
  {
    hor -= _rcMv.hor;
    ver -= _rcMv.ver;

    return  *this;
  }


  //! shift right with rounding
  void divideByPowerOf2 (const int i)
  {
    if (i != 0)
    {
      const int offset = (1 << (i - 1));
      hor = (hor + offset - (hor >= 0)) >> i;
      ver = (ver + offset - (ver >= 0)) >> i;
    }
  }

  const Mv& operator<<= (const int i)
  {
    hor <<= i;
    ver <<= i;
    return  *this;
  }

  const Mv& operator>>= ( const int i )
  {
    if (i != 0)
    {
      const int offset = (1 << (i - 1));
      hor = (hor + offset - (hor >= 0)) >> i;
      ver = (ver + offset - (ver >= 0)) >> i;
    }
    return  *this;
  }

  const Mv operator - ( const Mv& rcMv ) const
  {
    return Mv( hor - rcMv.hor, ver - rcMv.ver );
  }

  const Mv operator + ( const Mv& rcMv ) const
  {
    return Mv( hor + rcMv.hor, ver + rcMv.ver );
  }

  bool operator== ( const Mv& rcMv ) const
  {
    return ( hor == rcMv.hor && ver == rcMv.ver );
  }

  bool operator!= ( const Mv& rcMv ) const
  {
    return !( *this == rcMv );
  }

  const Mv scaleMv( int iScale ) const
  {
    const int mvx = Clip3(MV_MIN, MV_MAX, (iScale * getHor() + 128 - (iScale * getHor() >= 0)) >> 8);
    const int mvy = Clip3(MV_MIN, MV_MAX, (iScale * getVer() + 128 - (iScale * getVer() >= 0)) >> 8);
    return Mv( mvx, mvy );
  }

  void changePrecision(const MvPrecision& src, const MvPrecision& dst)
  {
    const int shift = (int)dst - (int)src;
    if (shift >= 0)
    {
      *this <<= shift;
    }
    else
    {
      const int rightShift = -shift;
      const int nOffset = 1 << (rightShift - 1);
      hor = hor >= 0 ? (hor + nOffset - 1) >> rightShift : (hor + nOffset) >> rightShift;
      ver = ver >= 0 ? (ver + nOffset - 1) >> rightShift : (ver + nOffset) >> rightShift;
    }
  }

  void roundToPrecision(const MvPrecision& src, const MvPrecision& dst)
  {
    changePrecision(src, dst);
    changePrecision(dst, src);
  }

  // translational MV
  void changeTransPrecInternal2Amvr(const int amvr)
  {
    changePrecision(MV_PRECISION_INTERNAL, m_amvrPrecision[amvr]);
  }

  void changeTransPrecAmvr2Internal(const int amvr)
  {
    changePrecision(m_amvrPrecision[amvr], MV_PRECISION_INTERNAL);
  }

  void roundTransPrecInternal2Amvr(const int amvr)
  {
    roundToPrecision(MV_PRECISION_INTERNAL, m_amvrPrecision[amvr]);
  }

  // affine MV
  void changeAffinePrecInternal2Amvr(const int amvr)
  {
    changePrecision(MV_PRECISION_INTERNAL, m_amvrPrecAffine[amvr]);
  }

  void changeAffinePrecAmvr2Internal(const int amvr)
  {
    changePrecision(m_amvrPrecAffine[amvr], MV_PRECISION_INTERNAL);
  }

  void roundAffinePrecInternal2Amvr(const int amvr)
  {
    roundToPrecision(MV_PRECISION_INTERNAL, m_amvrPrecAffine[amvr]);
  }

  // IBC block vector
  void changeIbcPrecInternal2Amvr(const int amvr)
  {
    changePrecision(MV_PRECISION_INTERNAL, m_amvrPrecIbc[amvr]);
  }

  void changeIbcPrecAmvr2Internal(const int amvr)
  {
    changePrecision(m_amvrPrecIbc[amvr], MV_PRECISION_INTERNAL);
  }

  void roundIbcPrecInternal2Amvr(const int amvr)
  {
    roundToPrecision(MV_PRECISION_INTERNAL, m_amvrPrecIbc[amvr]);
  }


  Mv getSymmvdMv(const Mv& curMvPred, const Mv& tarMvPred)
  {
    return Mv(tarMvPred.hor - hor + curMvPred.hor, tarMvPred.ver - ver + curMvPred.ver);
  }

  void clipToStorageBitDepth()
  {
    hor = Clip3( -(1 << 17), (1 << 17) - 1, hor );
    ver = Clip3( -(1 << 17), (1 << 17) - 1, ver );
  }
  void mvCliptoStorageBitDepth()  // periodic clipping
  {
    hor = (hor + mvClipPeriod) & (mvClipPeriod - 1);
    hor = (hor >= halMvClipPeriod) ? (hor - mvClipPeriod) : hor;
    ver = (ver + mvClipPeriod) & (mvClipPeriod - 1);
    ver = (ver >= halMvClipPeriod) ? (ver - mvClipPeriod) : ver;
  }
};// END CLASS DEFINITION MV

namespace std
{
  template <>
  struct hash<Mv> : public unary_function<Mv, uint64_t>
  {
    uint64_t operator()(const Mv& value) const
    {
      return (((uint64_t)value.hor << 32) + value.ver);
    }
  };
};
extern void(*clipMv) ( Mv& rcMv, const struct Position& pos, const struct Size& size, const class SPS& sps, const class PPS& pps );
void clipMvInPic ( Mv& rcMv, const struct Position& pos, const struct Size& size, const class SPS& sps, const class PPS& pps );
void clipMvInSubpic ( Mv& rcMv, const struct Position& pos, const struct Size& size, const class SPS& sps, const class PPS& pps );

bool wrapClipMv( Mv& rcMv, const Position& pos,
                 const struct Size& size,
                 const SPS *sps
               , const PPS* pps
);

void roundAffineMv( int& mvx, int& mvy, int nShift );

//! \}

#endif // __MV__
