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/**
 * \file
 * \brief Implementation of AffineGradientSearch class
 */

// ====================================================================================================================
// Includes
// ====================================================================================================================

#include "AffineGradientSearch.h"


//! \ingroup CommonLib
//! \{

// ====================================================================================================================
// Private member functions
// ====================================================================================================================

AffineGradientSearch::AffineGradientSearch()
{
  m_HorizontalSobelFilter = xHorizontalSobelFilter;
  m_VerticalSobelFilter = xVerticalSobelFilter;
  m_EqualCoeffComputer = xEqualCoeffComputer;

#if ENABLE_SIMD_OPT_AFFINE_ME
#ifdef TARGET_SIMD_X86
  initAffineGradientSearchX86();
#endif
#endif
}

void AffineGradientSearch::xHorizontalSobelFilter(Pel *const pPred, const ptrdiff_t predStride, int *const pDerivate,
                                                  const ptrdiff_t derivateBufStride, const int width, const int height)
{
  for ( int j = 1; j < height - 1; j++ )
  {
    for ( int k = 1; k < width - 1; k++ )
    {
      const ptrdiff_t iCenter = j * predStride + k;

      pDerivate[j * derivateBufStride + k] =
        (pPred[iCenter + 1 - predStride] -
          pPred[iCenter - 1 - predStride] +
          (pPred[iCenter + 1] << 1) -
          (pPred[iCenter - 1] << 1) +
          pPred[iCenter + 1 + predStride] -
          pPred[iCenter - 1 + predStride]);
    }

    pDerivate[j * derivateBufStride] = pDerivate[j * derivateBufStride + 1];
    pDerivate[j * derivateBufStride + width - 1] = pDerivate[j * derivateBufStride + width - 2];
  }

  pDerivate[0] = pDerivate[derivateBufStride + 1];
  pDerivate[width - 1] = pDerivate[derivateBufStride + width - 2];
  pDerivate[(height - 1) * derivateBufStride] = pDerivate[(height - 2) * derivateBufStride + 1];
  pDerivate[(height - 1) * derivateBufStride + width - 1] = pDerivate[(height - 2) * derivateBufStride + (width - 2)];

  for ( int j = 1; j < width - 1; j++ )
  {
    pDerivate[j] = pDerivate[derivateBufStride + j];
    pDerivate[(height - 1) * derivateBufStride + j] = pDerivate[(height - 2) * derivateBufStride + j];
  }
}

void AffineGradientSearch::xVerticalSobelFilter(Pel *const pPred, const ptrdiff_t predStride, int *const pDerivate,
                                                const ptrdiff_t derivateBufStride, const int width, const int height)
{
  for ( int k = 1; k < width - 1; k++ )
  {
    for ( int j = 1; j < height - 1; j++ )
    {
      const ptrdiff_t iCenter = j * predStride + k;

      pDerivate[j * derivateBufStride + k] =
        (pPred[iCenter + predStride - 1] -
          pPred[iCenter - predStride - 1] +
          (pPred[iCenter + predStride] << 1) -
          (pPred[iCenter - predStride] << 1) +
          pPred[iCenter + predStride + 1] -
          pPred[iCenter - predStride + 1]);
    }

    pDerivate[k] = pDerivate[derivateBufStride + k];
    pDerivate[(height - 1) * derivateBufStride + k] = pDerivate[(height - 2) * derivateBufStride + k];
  }

  pDerivate[0] = pDerivate[derivateBufStride + 1];
  pDerivate[width - 1] = pDerivate[derivateBufStride + width - 2];
  pDerivate[(height - 1) * derivateBufStride] = pDerivate[(height - 2) * derivateBufStride + 1];
  pDerivate[(height - 1) * derivateBufStride + width - 1] = pDerivate[(height - 2) * derivateBufStride + (width - 2)];

  for ( int j = 1; j < height - 1; j++ )
  {
    pDerivate[j * derivateBufStride] = pDerivate[j * derivateBufStride + 1];
    pDerivate[j * derivateBufStride + width - 1] = pDerivate[j * derivateBufStride + width - 2];
  }
}

void AffineGradientSearch::xEqualCoeffComputer(Pel *pResidue, ptrdiff_t residueStride, int **ppDerivate,
                                               ptrdiff_t derivateBufStride, int64_t (*pEqualCoeff)[7], int width,
                                               int height, bool b6Param)
{
  int affineParamNum = b6Param ? 6 : 4;

  for ( int j = 0; j != height; j++ )
  {
    int cy = ((j >> 2) << 2) + 2;
    for ( int k = 0; k != width; k++ )
    {
      int iC[6];

      ptrdiff_t idx = j * derivateBufStride + k;
      int cx = ((k >> 2) << 2) + 2;
      if ( !b6Param )
      {
        iC[0] = ppDerivate[0][idx];
        iC[1] = cx * ppDerivate[0][idx] + cy * ppDerivate[1][idx];
        iC[2] = ppDerivate[1][idx];
        iC[3] = cy * ppDerivate[0][idx] - cx * ppDerivate[1][idx];
      }
      else
      {
        iC[0] = ppDerivate[0][idx];
        iC[1] = cx * ppDerivate[0][idx];
        iC[2] = ppDerivate[1][idx];
        iC[3] = cx * ppDerivate[1][idx];
        iC[4] = cy * ppDerivate[0][idx];
        iC[5] = cy * ppDerivate[1][idx];
      }
      for ( int col = 0; col < affineParamNum; col++ )
      {
        for ( int row = 0; row < affineParamNum; row++ )
        {
          pEqualCoeff[col + 1][row] += (int64_t)iC[col] * iC[row];
        }
        pEqualCoeff[col + 1][affineParamNum] += ((int64_t)iC[col] * pResidue[idx]) << 3;
      }
    }
  }
}


//! \}