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Avoid several backward reference copies.

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An extra VP8LBackwardRefs struct is used but it was used internally anyway.

Change-Id: Ifcb36ce42b8c21ef3c7a1daf38cb7f714687fcb2
This commit is contained in:
Vincent Rabaud
2017-04-13 16:52:38 +02:00
parent 4bb1f607d7
commit 690efd82f8
4 changed files with 62 additions and 80 deletions
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54
src/enc/backward_references_enc.c
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@ -173,21 +173,6 @@ static WEBP_INLINE void BackwardRefsCursorAdd(VP8LBackwardRefs* const refs,
b->start_[b->size_++] = v;
}
int VP8LBackwardRefsCopy(const VP8LBackwardRefs* const src,
VP8LBackwardRefs* const dst) {
const PixOrCopyBlock* b = src->refs_;
ClearBackwardRefs(dst);
assert(src->block_size_ == dst->block_size_);
while (b != NULL) {
PixOrCopyBlock* const new_b = BackwardRefsNewBlock(dst);
if (new_b == NULL) return 0; // dst->error_ is set
memcpy(new_b->start_, b->start_, b->size_ * sizeof(*b->start_));
new_b->size_ = b->size_;
b = b->next_;
}
return 1;
}
// -----------------------------------------------------------------------------
// Hash chains
@ -588,7 +573,7 @@ static void ConvertPopulationCountTableToBitEstimates(
}
static int CostModelBuild(CostModel* const m, int cache_bits,
VP8LBackwardRefs* const refs) {
const VP8LBackwardRefs* const refs) {
int ok = 0;
VP8LHistogram* const histo = VP8LAllocateHistogram(cache_bits);
if (histo == NULL) goto Error;
@ -1084,7 +1069,7 @@ static WEBP_INLINE void PushInterval(CostManager* const manager,
static int BackwardReferencesHashChainDistanceOnly(
int xsize, int ysize, const uint32_t* const argb, int cache_bits,
const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs,
const VP8LHashChain* const hash_chain, const VP8LBackwardRefs* const refs,
uint16_t* const dist_array) {
int i;
int ok = 0;
@ -1279,7 +1264,8 @@ static int BackwardReferencesHashChainFollowChosenPath(
// Returns 1 on success.
static int BackwardReferencesTraceBackwards(
int xsize, int ysize, const uint32_t* const argb, int cache_bits,
const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs) {
const VP8LHashChain* const hash_chain,
const VP8LBackwardRefs* const refs_src, VP8LBackwardRefs* const refs_dst) {
int ok = 0;
const int dist_array_size = xsize * ysize;
uint16_t* chosen_path = NULL;
@ -1289,13 +1275,14 @@ static int BackwardReferencesTraceBackwards(
if (dist_array == NULL) goto Error;
if (!BackwardReferencesHashChainDistanceOnly(xsize, ysize, argb, cache_bits,
hash_chain, refs, dist_array)) {
if (!BackwardReferencesHashChainDistanceOnly(
xsize, ysize, argb, cache_bits, hash_chain, refs_src, dist_array)) {
goto Error;
}
TraceBackwards(dist_array, dist_array_size, &chosen_path, &chosen_path_size);
if (!BackwardReferencesHashChainFollowChosenPath(
argb, cache_bits, chosen_path, chosen_path_size, hash_chain, refs)) {
argb, cache_bits, chosen_path, chosen_path_size, hash_chain,
refs_dst)) {
goto Error;
}
ok = 1;
@ -1458,8 +1445,7 @@ static int BackwardRefsWithLocalCache(const uint32_t* const argb,
static VP8LBackwardRefs* GetBackwardReferencesLowEffort(
int width, int height, const uint32_t* const argb,
int* const cache_bits, const VP8LHashChain* const hash_chain,
VP8LBackwardRefs refs_array[2]) {
VP8LBackwardRefs* refs_lz77 = &refs_array[0];
VP8LBackwardRefs* const refs_lz77) {
*cache_bits = 0;
if (!BackwardReferencesLz77(width, height, argb, 0, hash_chain, refs_lz77)) {
return NULL;
@ -1471,13 +1457,11 @@ static VP8LBackwardRefs* GetBackwardReferencesLowEffort(
static VP8LBackwardRefs* GetBackwardReferences(
int width, int height, const uint32_t* const argb, int quality,
int* const cache_bits, const VP8LHashChain* const hash_chain,
VP8LBackwardRefs refs_array[2]) {
VP8LBackwardRefs* const refs_lz77, VP8LBackwardRefs* const refs_rle) {
int lz77_is_useful;
int cache_bits_lz77 = *cache_bits, cache_bits_rle = *cache_bits;
double bit_cost_lz77, bit_cost_rle;
VP8LBackwardRefs* best = NULL;
VP8LBackwardRefs* refs_lz77 = &refs_array[0];
VP8LBackwardRefs* refs_rle = &refs_array[1];
VP8LHistogram* histo = NULL;
// Compute LZ77 with no cache (0 bits), as the ideal LZ77 with a color cache
@ -1531,19 +1515,14 @@ static VP8LBackwardRefs* GetBackwardReferences(
const int try_lz77_trace_backwards = (quality >= 25);
best = refs_lz77; // default guess: lz77 is better
if (try_lz77_trace_backwards) {
VP8LBackwardRefs* const refs_trace = refs_rle;
if (!VP8LBackwardRefsCopy(refs_lz77, refs_trace)) {
best = NULL;
goto Error;
}
if (BackwardReferencesTraceBackwards(width, height, argb, cache_bits_lz77,
hash_chain, refs_trace)) {
hash_chain, refs_lz77, refs_rle)) {
double bit_cost_trace;
// Evaluate LZ77 coding.
VP8LHistogramCreate(histo, refs_trace, cache_bits_lz77);
VP8LHistogramCreate(histo, refs_rle, cache_bits_lz77);
bit_cost_trace = VP8LHistogramEstimateBits(histo);
if (bit_cost_trace < bit_cost_lz77) {
best = refs_trace;
best = refs_rle;
}
}
}
@ -1563,12 +1542,13 @@ static VP8LBackwardRefs* GetBackwardReferences(
VP8LBackwardRefs* VP8LGetBackwardReferences(
int width, int height, const uint32_t* const argb, int quality,
int low_effort, int* const cache_bits,
const VP8LHashChain* const hash_chain, VP8LBackwardRefs refs_array[2]) {
const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs_tmp1,
VP8LBackwardRefs* const refs_tmp2) {
if (low_effort) {
return GetBackwardReferencesLowEffort(width, height, argb, cache_bits,
hash_chain, refs_array);
hash_chain, refs_tmp1);
} else {
return GetBackwardReferences(width, height, argb, quality, cache_bits,
hash_chain, refs_array);
hash_chain, refs_tmp1, refs_tmp2);
}
}