fg_compute_block_avg_sse4

fg_compute_block_avg_sse4.c

int16_t fg_compute_block_avg_sse4(int16_t *dstSampleBlk8, uint32_t widthComp, uint16_t *pNumSamples,
                      uint8_t ySize, uint8_t xSize, uint8_t bitDepth)
{
  uint16_t blockAvg   = 0;
  uint16_t numSamples = 0;

  __m128i acc = _mm_setzero_si128();

  for (int i = 0; i < ySize; i+=1, numSamples+=8)
  {
      __m128i x = _mm_loadu_si128(&dstSampleBlk8[i*widthComp]);
      acc = _mm_adds_epi16(acc, x);
  }

  if (numSamples > 0)
  {
    acc = _mm_hadd_epi16(acc, acc);
    acc = _mm_hadd_epi16(acc, acc);
    acc = _mm_hadd_epi16(acc, acc);
    blockAvg = _mm_cvtsi128_si32(acc);
    blockAvg /= numSamples;
    blockAvg >>= (bitDepth - 8); /* to handle high bit depths */
  }

  // assert(blockAvg < (1 << 8));
  *pNumSamples = numSamples;

  // blockAvg = (int16_t) OVMIN(OVMAX(0, blockAvg), (1 << 8) - 1 );
  blockAvg = (int16_t) ov_clip_uintp2((uint32_t)blockAvg, 8);
  return blockAvg;
}