Function IdctResAddPred8x8_ref

test/decoder/DecUT_IdctResAddPred.cpp:55–141

}

void IdctResAddPred8x8_ref (uint8_t* pPred, const int32_t kiStride, int16_t* pRs) {
  int16_t p[8], b[8];
  int16_t a[4];

  int16_t iTmp[64];
  int16_t iRes[64];

  // Horizontal
  for (int i = 0; i < 8; i++) {
    for (int j = 0; j < 8; j++) {
      p[j] = pRs[j + (i << 3)];
    }
    a[0] = p[0] + p[4];
    a[1] = p[0] - p[4];
    a[2] = p[6] - (p[2] >> 1);
    a[3] = p[2] + (p[6] >> 1);

    b[0] =  a[0] + a[3];
    b[2] =  a[1] - a[2];
    b[4] =  a[1] + a[2];
    b[6] =  a[0] - a[3];

    a[0] = -p[3] + p[5] - p[7] - (p[7] >> 1);
    a[1] =  p[1] + p[7] - p[3] - (p[3] >> 1);
    a[2] = -p[1] + p[7] + p[5] + (p[5] >> 1);
    a[3] =  p[3] + p[5] + p[1] + (p[1] >> 1);

    b[1] =  a[0] + (a[3] >> 2);
    b[3] =  a[1] + (a[2] >> 2);
    b[5] =  a[2] - (a[1] >> 2);
    b[7] =  a[3] - (a[0] >> 2);

    iTmp[0 + (i << 3)] = b[0] + b[7];
    iTmp[1 + (i << 3)] = b[2] - b[5];
    iTmp[2 + (i << 3)] = b[4] + b[3];
    iTmp[3 + (i << 3)] = b[6] + b[1];
    iTmp[4 + (i << 3)] = b[6] - b[1];
    iTmp[5 + (i << 3)] = b[4] - b[3];
    iTmp[6 + (i << 3)] = b[2] + b[5];
    iTmp[7 + (i << 3)] = b[0] - b[7];
  }

  //Vertical
  for (int i = 0; i < 8; i++) {
    for (int j = 0; j < 8; j++) {
      p[j] = iTmp[i + (j << 3)];
    }

    a[0] =  p[0] + p[4];
    a[1] =  p[0] - p[4];
    a[2] =  p[6] - (p[2] >> 1);
    a[3] =  p[2] + (p[6] >> 1);

    b[0] = a[0] + a[3];
    b[2] = a[1] - a[2];
    b[4] = a[1] + a[2];
    b[6] = a[0] - a[3];