Switch ExtraCost to ints and implement it in SSE.

The histograms count the occurrences of len/dist in entropy images.
Those (at most (1<<14) by (1<<14)) are sub-sampled by at least
MIN_HUFFMAN_BITS == 2, hence at most 24 bits in a histogram value.
At most, we multiply by 19 (because the longest histogram is of
size 40 and we do 40>>1, cf code) for the bit cost. So it all fits
in 32 bits.

Change-Id: Ife24b035f54794851ff31f2fac07901f724c6d7f
This commit is contained in:
Vincent Rabaud
2023-05-31 15:41:43 +02:00
parent 15b365083d
commit 828b4ce062
5 changed files with 94 additions and 37 deletions

View File

@ -358,15 +358,17 @@ static WEBP_INLINE float GetCombinedEntropy(const uint32_t* const X,
// Estimates the Entropy + Huffman + other block overhead size cost.
float VP8LHistogramEstimateBits(VP8LHistogram* const p) {
return
PopulationCost(p->literal_, VP8LHistogramNumCodes(p->palette_code_bits_),
NULL, &p->is_used_[0])
+ PopulationCost(p->red_, NUM_LITERAL_CODES, NULL, &p->is_used_[1])
+ PopulationCost(p->blue_, NUM_LITERAL_CODES, NULL, &p->is_used_[2])
+ PopulationCost(p->alpha_, NUM_LITERAL_CODES, NULL, &p->is_used_[3])
+ PopulationCost(p->distance_, NUM_DISTANCE_CODES, NULL, &p->is_used_[4])
+ VP8LExtraCost(p->literal_ + NUM_LITERAL_CODES, NUM_LENGTH_CODES)
+ VP8LExtraCost(p->distance_, NUM_DISTANCE_CODES);
return PopulationCost(p->literal_,
VP8LHistogramNumCodes(p->palette_code_bits_), NULL,
&p->is_used_[0]) +
PopulationCost(p->red_, NUM_LITERAL_CODES, NULL, &p->is_used_[1]) +
PopulationCost(p->blue_, NUM_LITERAL_CODES, NULL, &p->is_used_[2]) +
PopulationCost(p->alpha_, NUM_LITERAL_CODES, NULL, &p->is_used_[3]) +
PopulationCost(p->distance_, NUM_DISTANCE_CODES, NULL,
&p->is_used_[4]) +
(float)VP8LExtraCost(p->literal_ + NUM_LITERAL_CODES,
NUM_LENGTH_CODES) +
(float)VP8LExtraCost(p->distance_, NUM_DISTANCE_CODES);
}
// -----------------------------------------------------------------------------
@ -381,9 +383,9 @@ static int GetCombinedHistogramEntropy(const VP8LHistogram* const a,
*cost += GetCombinedEntropy(a->literal_, b->literal_,
VP8LHistogramNumCodes(palette_code_bits),
a->is_used_[0], b->is_used_[0], 0);
*cost += VP8LExtraCostCombined(a->literal_ + NUM_LITERAL_CODES,
b->literal_ + NUM_LITERAL_CODES,
NUM_LENGTH_CODES);
*cost += (float)VP8LExtraCostCombined(a->literal_ + NUM_LITERAL_CODES,
b->literal_ + NUM_LITERAL_CODES,
NUM_LENGTH_CODES);
if (*cost > cost_threshold) return 0;
if (a->trivial_symbol_ != VP8L_NON_TRIVIAL_SYM &&
@ -417,8 +419,8 @@ static int GetCombinedHistogramEntropy(const VP8LHistogram* const a,
*cost +=
GetCombinedEntropy(a->distance_, b->distance_, NUM_DISTANCE_CODES,
a->is_used_[4], b->is_used_[4], 0);
*cost +=
VP8LExtraCostCombined(a->distance_, b->distance_, NUM_DISTANCE_CODES);
*cost += (float)VP8LExtraCostCombined(a->distance_, b->distance_,
NUM_DISTANCE_CODES);
if (*cost > cost_threshold) return 0;
return 1;
@ -506,11 +508,11 @@ static void UpdateHistogramCost(VP8LHistogram* const h) {
PopulationCost(h->alpha_, NUM_LITERAL_CODES, &alpha_sym, &h->is_used_[3]);
const float distance_cost =
PopulationCost(h->distance_, NUM_DISTANCE_CODES, NULL, &h->is_used_[4]) +
VP8LExtraCost(h->distance_, NUM_DISTANCE_CODES);
(float)VP8LExtraCost(h->distance_, NUM_DISTANCE_CODES);
const int num_codes = VP8LHistogramNumCodes(h->palette_code_bits_);
h->literal_cost_ =
PopulationCost(h->literal_, num_codes, NULL, &h->is_used_[0]) +
VP8LExtraCost(h->literal_ + NUM_LITERAL_CODES, NUM_LENGTH_CODES);
(float)VP8LExtraCost(h->literal_ + NUM_LITERAL_CODES, NUM_LENGTH_CODES);
h->red_cost_ =
PopulationCost(h->red_, NUM_LITERAL_CODES, &red_sym, &h->is_used_[1]);
h->blue_cost_ =