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new segmentation algorithm

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fixes the 'blocky sky problem' (saturation problem: when luma was flat,
chroma noise was taking over, resulting in random segment id assigned.
When just using a common uniform segment was better).

+ side clean-up and readibility/experimentability MACRO'ization
+ added '-map 7' option

Change-Id: I35982a9e43c0fecbfdd7b05e4813e8ba8c121d71
This commit is contained in:
skal
2012-09-03 19:40:52 +02:00
parent 2cf1f81590
commit 5725cabac0
6 changed files with 135 additions and 95 deletions
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24
src/dsp/enc_sse2.c
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@ -25,13 +25,15 @@ extern "C" {
// Compute susceptibility based on DCT-coeff histograms:
// the higher, the "easier" the macroblock is to compress.
static int CollectHistogramSSE2(const uint8_t* ref, const uint8_t* pred,
int start_block, int end_block) {
int histo[MAX_COEFF_THRESH + 1] = { 0 };
int16_t out[16];
int j, k;
static void CollectHistogramSSE2(const uint8_t* ref, const uint8_t* pred,
int start_block, int end_block,
VP8Histogram* const histo) {
const __m128i max_coeff_thresh = _mm_set1_epi16(MAX_COEFF_THRESH);
int j;
for (j = start_block; j < end_block; ++j) {
int16_t out[16];
int k;
VP8FTransform(ref + VP8DspScan[j], pred + VP8DspScan[j], out);
// Convert coefficients to bin (within out[]).
@ -47,9 +49,9 @@ static int CollectHistogramSSE2(const uint8_t* ref, const uint8_t* pred,
const __m128i xor1 = _mm_xor_si128(out1, sign1);
const __m128i abs0 = _mm_sub_epi16(xor0, sign0);
const __m128i abs1 = _mm_sub_epi16(xor1, sign1);
// v = abs(out) >> 2
const __m128i v0 = _mm_srai_epi16(abs0, 2);
const __m128i v1 = _mm_srai_epi16(abs1, 2);
// v = abs(out) >> 3
const __m128i v0 = _mm_srai_epi16(abs0, 3);
const __m128i v1 = _mm_srai_epi16(abs1, 3);
// bin = min(v, MAX_COEFF_THRESH)
const __m128i bin0 = _mm_min_epi16(v0, max_coeff_thresh);
const __m128i bin1 = _mm_min_epi16(v1, max_coeff_thresh);
@ -58,13 +60,11 @@ static int CollectHistogramSSE2(const uint8_t* ref, const uint8_t* pred,
_mm_storeu_si128((__m128i*)&out[8], bin1);
}
// Use bin to update histogram.
// Convert coefficients to bin.
for (k = 0; k < 16; ++k) {
histo[out[k]]++;
histo->distribution[out[k]]++;
}
}
return VP8GetAlpha(histo);
}
//------------------------------------------------------------------------------