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Speedups for empty histograms.

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When histograms are empty, it is easy to add them.
They should also not be considered when merging histograms
(it is a waste of CPU).
This does not change the compression performance,
just the speed.

Change-Id: I42c721ca0f9c5ea067e73b792aa3db6d5e71d01f
This commit is contained in:
Vincent Rabaud
2018-09-28 15:32:25 +02:00
parent dea3e89983
commit decf6f6b87
3 changed files with 116 additions and 46 deletions
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53
src/dsp/lossless_enc.c
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@ -643,25 +643,56 @@ static void AddVectorEq_C(const uint32_t* a, uint32_t* out, int size) {
for (i = 0; i < size; ++i) out[i] += a[i];
}
#define ADD(X, ARG, LEN) do { \
if (a->is_used_[X]) { \
if (b->is_used_[X]) { \
VP8LAddVector(a->ARG, b->ARG, out->ARG, (LEN)); \
} else { \
memcpy(&out->ARG[0], &a->ARG[0], (LEN) * sizeof(out->ARG[0])); \
} \
} else if (b->is_used_[X]) { \
memcpy(&out->ARG[0], &b->ARG[0], (LEN) * sizeof(out->ARG[0])); \
} else { \
memset(&out->ARG[0], 0, (LEN) * sizeof(out->ARG[0])); \
} \
} while (0)
#define ADD_EQ(X, ARG, LEN) do { \
if (a->is_used_[X]) { \
if (out->is_used_[X]) { \
VP8LAddVectorEq(a->ARG, out->ARG, (LEN)); \
} else { \
memcpy(&out->ARG[0], &a->ARG[0], (LEN) * sizeof(out->ARG[0])); \
} \
} \
} while (0)
void VP8LHistogramAdd(const VP8LHistogram* const a,
const VP8LHistogram* const b, VP8LHistogram* const out) {
int i;
const int literal_size = VP8LHistogramNumCodes(a->palette_code_bits_);
assert(a->palette_code_bits_ == b->palette_code_bits_);
if (b != out) {
VP8LAddVector(a->literal_, b->literal_, out->literal_, literal_size);
VP8LAddVector(a->distance_, b->distance_, out->distance_,
NUM_DISTANCE_CODES);
VP8LAddVector(a->red_, b->red_, out->red_, NUM_LITERAL_CODES);
VP8LAddVector(a->blue_, b->blue_, out->blue_, NUM_LITERAL_CODES);
VP8LAddVector(a->alpha_, b->alpha_, out->alpha_, NUM_LITERAL_CODES);
ADD(0, literal_, literal_size);
ADD(1, red_, NUM_LITERAL_CODES);
ADD(2, blue_, NUM_LITERAL_CODES);
ADD(3, alpha_, NUM_LITERAL_CODES);
ADD(4, distance_, NUM_DISTANCE_CODES);
for (i = 0; i < 5; ++i) {
out->is_used_[i] = (a->is_used_[i] | b->is_used_[i]);
}
} else {
VP8LAddVectorEq(a->literal_, out->literal_, literal_size);
VP8LAddVectorEq(a->distance_, out->distance_, NUM_DISTANCE_CODES);
VP8LAddVectorEq(a->red_, out->red_, NUM_LITERAL_CODES);
VP8LAddVectorEq(a->blue_, out->blue_, NUM_LITERAL_CODES);
VP8LAddVectorEq(a->alpha_, out->alpha_, NUM_LITERAL_CODES);
ADD_EQ(0, literal_, literal_size);
ADD_EQ(1, red_, NUM_LITERAL_CODES);
ADD_EQ(2, blue_, NUM_LITERAL_CODES);
ADD_EQ(3, alpha_, NUM_LITERAL_CODES);
ADD_EQ(4, distance_, NUM_DISTANCE_CODES);
for (i = 0; i < 5; ++i) out->is_used_[i] |= a->is_used_[i];
}
}
#undef ADD
#undef ADD_EQ
//------------------------------------------------------------------------------
// Image transforms.