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Switch the histogram_enc.h API to fixed point

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Speedups: 4% with '-lossless', 8% with '-lossless -q 100 -m6'

Change-Id: I8f1c244b290d48132c1edc6a1c9fc3f79fef68ec
This commit is contained in:
Vincent Rabaud
2024-07-02 14:33:37 +02:00
parent ac1e410ded
commit 66408c2c7c
6 changed files with 148 additions and 139 deletions
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18
src/enc/vp8l_enc.c
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@ -141,8 +141,8 @@ static int AnalyzeEntropy(const uint32_t* argb,
curr_row += argb_stride;
}
{
float entropy_comp[kHistoTotal];
float entropy[kNumEntropyIx];
uint64_t entropy_comp[kHistoTotal];
uint64_t entropy[kNumEntropyIx];
int k;
int last_mode_to_analyze = use_palette ? kPalette : kSpatialSubGreen;
int j;
@ -180,21 +180,19 @@ static int AnalyzeEntropy(const uint32_t* argb,
// When including transforms, there is an overhead in bits from
// storing them. This overhead is small but matters for small images.
// For spatial, there are 14 transformations.
entropy[kSpatial] += RightShiftRound(
(uint64_t)VP8LSubSampleSize(width, transform_bits) *
VP8LSubSampleSize(height, transform_bits) * VP8LFastLog2(14),
LOG_2_PRECISION_BITS);
entropy[kSpatial] += (uint64_t)VP8LSubSampleSize(width, transform_bits) *
VP8LSubSampleSize(height, transform_bits) *
VP8LFastLog2(14);
// For color transforms: 24 as only 3 channels are considered in a
// ColorTransformElement.
entropy[kSpatialSubGreen] += RightShiftRound(
entropy[kSpatialSubGreen] +=
(uint64_t)VP8LSubSampleSize(width, transform_bits) *
VP8LSubSampleSize(height, transform_bits) * VP8LFastLog2(24),
LOG_2_PRECISION_BITS);
VP8LSubSampleSize(height, transform_bits) * VP8LFastLog2(24);
// For palettes, add the cost of storing the palette.
// We empirically estimate the cost of a compressed entry as 8 bits.
// The palette is differential-coded when compressed hence a much
// lower cost than sizeof(uint32_t)*8.
entropy[kPalette] += palette_size * 8;
entropy[kPalette] += (palette_size * 8ull) << LOG_2_PRECISION_BITS;
*min_entropy_ix = kDirect;
for (k = kDirect + 1; k <= last_mode_to_analyze; ++k) {