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use block-based allocation for backward refs storage, and free-lists
Non-photo source produce far less literal reference and their buffer is usually much smaller than the picture size if its compresses well. Hence, use a block-base allocation (and recycling) to avoid pre-allocating a buffer with maximal size. This can reduce memory consumption up to 50% for non-photographic content. Encode speed is also a little better (1-2%) Change-Id: Icbc229e1e5a08976348e600c8906beaa26954a11
This commit is contained in:
parent
1ba61b09f9
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@ -23,6 +23,8 @@
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#define HASH_MULTIPLIER (0xc6a4a7935bd1e995ULL)
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#define MIN_BLOCK_SIZE 256 // minimum block size for backward references
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#define MAX_ENTROPY (1e30f)
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// 1M window (4M bytes) minus 120 special codes for short distances.
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@ -69,43 +71,106 @@ static WEBP_INLINE int FindMatchLength(const uint32_t* const array1,
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// -----------------------------------------------------------------------------
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// VP8LBackwardRefs
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struct PixOrCopyBlock {
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PixOrCopyBlock* next_; // next block (or NULL)
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PixOrCopy* start_; // data start
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int size_; // currently used size
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};
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static void ClearBackwardRefs(VP8LBackwardRefs* const refs) {
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assert(refs != NULL);
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refs->size = 0;
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if (refs->tail_ != NULL) {
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*refs->tail_ = refs->free_blocks_; // recycle all blocks at once
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}
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refs->free_blocks_ = refs->refs_;
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refs->tail_ = &refs->refs_;
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refs->last_block_ = NULL;
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refs->refs_ = NULL;
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}
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void VP8LBackwardRefsDelete(VP8LBackwardRefs* const refs) {
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if (refs != NULL) {
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WebPSafeFree(refs->refs);
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WebPSafeFree(refs);
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}
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}
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VP8LBackwardRefs* VP8LBackwardRefsNew(int max_size) {
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VP8LBackwardRefs* const refs =
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(VP8LBackwardRefs*)WebPSafeMalloc(1ULL, sizeof(*refs));
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if (refs == NULL) {
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return NULL;
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}
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void VP8LBackwardRefsClear(VP8LBackwardRefs* const refs) {
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assert(refs != NULL);
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ClearBackwardRefs(refs);
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refs->max_size = 0;
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refs->refs = (PixOrCopy*)WebPSafeMalloc(max_size, sizeof(*refs->refs));
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if (refs->refs == NULL) {
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WebPSafeFree(refs);
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return NULL;
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while (refs->free_blocks_ != NULL) {
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PixOrCopyBlock* const next = refs->free_blocks_->next_;
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WebPSafeFree(refs->free_blocks_);
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refs->free_blocks_ = next;
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}
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refs->max_size = max_size;
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return refs;
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}
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void VP8LBackwardRefsInit(VP8LBackwardRefs* const refs, int block_size) {
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assert(refs != NULL);
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memset(refs, 0, sizeof(*refs));
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refs->tail_ = &refs->refs_;
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refs->block_size_ =
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(block_size < MIN_BLOCK_SIZE) ? MIN_BLOCK_SIZE : block_size;
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}
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VP8LRefsCursor VP8LRefsCursorInit(const VP8LBackwardRefs* const refs) {
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VP8LRefsCursor c;
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c.cur_block_ = refs->refs_;
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if (refs->refs_ != NULL) {
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c.cur_pos = c.cur_block_->start_;
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c.last_pos_ = c.cur_pos + c.cur_block_->size_;
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} else {
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c.cur_pos = NULL;
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c.last_pos_ = NULL;
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}
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return c;
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}
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void VP8LRefsCursorNextBlock(VP8LRefsCursor* const c) {
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PixOrCopyBlock* const b = c->cur_block_->next_;
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c->cur_pos = (b == NULL) ? NULL : b->start_;
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c->last_pos_ = (b == NULL) ? NULL : b->start_ + b->size_;
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c->cur_block_ = b;
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}
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// Create a new block, either from the free list or allocated
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static PixOrCopyBlock* BackwardRefsNewBlock(VP8LBackwardRefs* const refs) {
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PixOrCopyBlock* b = refs->free_blocks_;
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if (b == NULL) { // allocate new memory chunk
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const size_t total_size =
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sizeof(*b) + refs->block_size_ * sizeof(*b->start_);
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b = (PixOrCopyBlock*)WebPSafeMalloc(1ULL, total_size);
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if (b == NULL) {
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refs->error_ |= 1;
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return NULL;
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}
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b->start_ = (PixOrCopy*)((uint8_t*)b + sizeof(*b)); // not always aligned
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} else { // recycle from free-list
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refs->free_blocks_ = b->next_;
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}
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*refs->tail_ = b;
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refs->tail_ = &b->next_;
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refs->last_block_ = b;
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b->next_ = NULL;
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b->size_ = 0;
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return b;
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}
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static WEBP_INLINE void BackwardRefsCursorAdd(VP8LBackwardRefs* const refs,
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const PixOrCopy v) {
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PixOrCopyBlock* b = refs->last_block_;
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if (b == NULL || b->size_ == refs->block_size_) {
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b = BackwardRefsNewBlock(refs);
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if (b == NULL) return; // refs->error_ is set
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}
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b->start_[b->size_++] = v;
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}
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int VP8LBackwardRefsCopy(const VP8LBackwardRefs* const src,
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VP8LBackwardRefs* const dst) {
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assert(src != NULL && dst != NULL);
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if (dst->max_size != src->max_size) {
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return 0;
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const PixOrCopyBlock* b = src->refs_;
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ClearBackwardRefs(dst);
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assert(src->block_size_ == dst->block_size_);
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while (b != NULL) {
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PixOrCopyBlock* const new_b = BackwardRefsNewBlock(dst);
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if (new_b == NULL) return 0; // dst->error_ is set
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memcpy(new_b->start_, b->start_, b->size_ * sizeof(*b->start_));
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new_b->size_ = b->size_;
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b = b->next_;
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}
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dst->size = src->size;
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memcpy(dst->refs, src->refs, src->size * sizeof(*src->refs));
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return 1;
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}
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@ -252,36 +317,35 @@ static int HashChainFindCopy(const VP8LHashChain* const p,
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}
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static WEBP_INLINE void PushBackCopy(VP8LBackwardRefs* const refs, int length) {
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int size = refs->size;
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while (length >= MAX_LENGTH) {
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refs->refs[size++] = PixOrCopyCreateCopy(1, MAX_LENGTH);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(1, MAX_LENGTH));
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length -= MAX_LENGTH;
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}
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if (length > 0) {
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refs->refs[size++] = PixOrCopyCreateCopy(1, length);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(1, length));
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}
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refs->size = size;
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}
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static void BackwardReferencesRle(int xsize, int ysize,
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const uint32_t* const argb,
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VP8LBackwardRefs* const refs) {
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static int BackwardReferencesRle(int xsize, int ysize,
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const uint32_t* const argb,
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VP8LBackwardRefs* const refs) {
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const int pix_count = xsize * ysize;
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int match_len = 0;
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int i;
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ClearBackwardRefs(refs);
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PushBackCopy(refs, match_len); // i=0 case
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refs->refs[refs->size++] = PixOrCopyCreateLiteral(argb[0]);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateLiteral(argb[0]));
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for (i = 1; i < pix_count; ++i) {
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if (argb[i] == argb[i - 1]) {
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++match_len;
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} else {
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PushBackCopy(refs, match_len);
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match_len = 0;
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refs->refs[refs->size++] = PixOrCopyCreateLiteral(argb[i]);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateLiteral(argb[i]));
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}
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}
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PushBackCopy(refs, match_len);
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return !refs->error_;
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}
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static int BackwardReferencesHashChain(int xsize, int ysize,
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@ -333,14 +397,15 @@ static int BackwardReferencesHashChain(int xsize, int ysize,
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if (len2 > len + 1) {
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const uint32_t pixel = argb[i];
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// Alternative#2 is a better match. So push pixel at 'i' as literal.
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PixOrCopy v;
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if (use_color_cache && VP8LColorCacheContains(&hashers, pixel)) {
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const int ix = VP8LColorCacheGetIndex(&hashers, pixel);
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refs->refs[refs->size] = PixOrCopyCreateCacheIdx(ix);
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v = PixOrCopyCreateCacheIdx(ix);
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} else {
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if (use_color_cache) VP8LColorCacheInsert(&hashers, pixel);
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refs->refs[refs->size] = PixOrCopyCreateLiteral(pixel);
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v = PixOrCopyCreateLiteral(pixel);
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}
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++refs->size;
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BackwardRefsCursorAdd(refs, v);
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i++; // Backward reference to be done for next pixel.
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len = len2;
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offset = offset2;
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@ -349,7 +414,7 @@ static int BackwardReferencesHashChain(int xsize, int ysize,
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if (len >= MAX_LENGTH) {
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len = MAX_LENGTH - 1;
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}
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refs->refs[refs->size++] = PixOrCopyCreateCopy(offset, len);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(offset, len));
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if (use_color_cache) {
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for (k = 0; k < len; ++k) {
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VP8LColorCacheInsert(&hashers, argb[i + k]);
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@ -365,22 +430,23 @@ static int BackwardReferencesHashChain(int xsize, int ysize,
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i += len;
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} else {
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const uint32_t pixel = argb[i];
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PixOrCopy v;
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if (use_color_cache && VP8LColorCacheContains(&hashers, pixel)) {
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// push pixel as a PixOrCopyCreateCacheIdx pixel
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const int ix = VP8LColorCacheGetIndex(&hashers, pixel);
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refs->refs[refs->size] = PixOrCopyCreateCacheIdx(ix);
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v = PixOrCopyCreateCacheIdx(ix);
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} else {
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if (use_color_cache) VP8LColorCacheInsert(&hashers, pixel);
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refs->refs[refs->size] = PixOrCopyCreateLiteral(pixel);
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v = PixOrCopyCreateLiteral(pixel);
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}
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++refs->size;
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BackwardRefsCursorAdd(refs, v);
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if (i + 1 < pix_count) {
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HashChainInsert(hash_chain, &argb[i], i);
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}
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++i;
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}
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}
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ok = 1;
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ok = !refs->error_;
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Error:
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if (cc_init) VP8LColorCacheClear(&hashers);
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return ok;
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@ -607,7 +673,7 @@ static int BackwardReferencesHashChainDistanceOnly(
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}
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// Last pixel still to do, it can only be a single step if not reached
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// through cheaper means already.
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ok = 1;
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ok = !refs->error_;
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Error:
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if (cc_init) VP8LColorCacheClear(&hashers);
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WebPSafeFree(cost_model);
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@ -671,7 +737,7 @@ static int BackwardReferencesHashChainFollowChosenPath(
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window_size, iter_pos, iter_limit,
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&offset, &len);
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assert(len == max_len);
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refs->refs[size] = PixOrCopyCreateCopy(offset, len);
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BackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(offset, len));
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if (use_color_cache) {
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for (k = 0; k < len; ++k) {
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VP8LColorCacheInsert(&hashers, argb[i + k]);
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@ -685,23 +751,23 @@ static int BackwardReferencesHashChainFollowChosenPath(
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}
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i += len;
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} else {
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PixOrCopy v;
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if (use_color_cache && VP8LColorCacheContains(&hashers, argb[i])) {
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// push pixel as a color cache index
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const int idx = VP8LColorCacheGetIndex(&hashers, argb[i]);
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refs->refs[size] = PixOrCopyCreateCacheIdx(idx);
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v = PixOrCopyCreateCacheIdx(idx);
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} else {
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if (use_color_cache) VP8LColorCacheInsert(&hashers, argb[i]);
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refs->refs[size] = PixOrCopyCreateLiteral(argb[i]);
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v = PixOrCopyCreateLiteral(argb[i]);
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}
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BackwardRefsCursorAdd(refs, v);
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if (i + 1 < pix_count) {
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HashChainInsert(hash_chain, &argb[i], i);
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}
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++i;
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}
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}
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assert(size <= refs->max_size);
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refs->size = size;
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ok = 1;
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ok = !refs->error_;
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Error:
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if (cc_init) VP8LColorCacheClear(&hashers);
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return ok;
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@ -741,39 +807,40 @@ static int BackwardReferencesTraceBackwards(int xsize, int ysize,
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}
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static void BackwardReferences2DLocality(int xsize,
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VP8LBackwardRefs* const refs) {
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int i;
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for (i = 0; i < refs->size; ++i) {
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if (PixOrCopyIsCopy(&refs->refs[i])) {
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const int dist = refs->refs[i].argb_or_distance;
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const VP8LBackwardRefs* const refs) {
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VP8LRefsCursor c = VP8LRefsCursorInit(refs);
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while (VP8LRefsCursorOk(&c)) {
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if (PixOrCopyIsCopy(c.cur_pos)) {
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const int dist = c.cur_pos->argb_or_distance;
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const int transformed_dist = DistanceToPlaneCode(xsize, dist);
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refs->refs[i].argb_or_distance = transformed_dist;
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c.cur_pos->argb_or_distance = transformed_dist;
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}
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VP8LRefsCursorNext(&c);
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}
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}
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VP8LBackwardRefs* VP8LGetBackwardReferences(
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int width, int height, const uint32_t* const argb, int quality,
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int cache_bits, int use_2d_locality, VP8LHashChain* const hash_chain,
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VP8LBackwardRefs* const refs_array[2]) {
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VP8LBackwardRefs refs_array[2]) {
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int lz77_is_useful;
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const int num_pix = width * height;
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VP8LBackwardRefs* best = NULL;
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VP8LBackwardRefs* const refs_lz77 = refs_array[0];
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VP8LBackwardRefs* const refs_rle = refs_array[1];
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VP8LBackwardRefs* const refs_lz77 = &refs_array[0];
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VP8LBackwardRefs* const refs_rle = &refs_array[1];
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ClearBackwardRefs(refs_lz77);
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if (!BackwardReferencesHashChain(width, height, argb, cache_bits, quality,
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hash_chain, refs_lz77)) {
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goto End;
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return NULL;
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}
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if (!BackwardReferencesRle(width, height, argb, refs_rle)) {
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return NULL;
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}
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ClearBackwardRefs(refs_rle);
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BackwardReferencesRle(width, height, argb, refs_rle);
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{
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double bit_cost_lz77, bit_cost_rle;
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VP8LHistogram* const histo = VP8LAllocateHistogram(cache_bits);
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if (histo == NULL) goto End;
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if (histo == NULL) return NULL;
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// Evaluate LZ77 coding.
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VP8LHistogramCreate(histo, refs_lz77, cache_bits);
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bit_cost_lz77 = VP8LHistogramEstimateBits(histo);
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@ -794,7 +861,7 @@ VP8LBackwardRefs* VP8LGetBackwardReferences(
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// Set recursion level for large images using a color cache.
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const int recursion_level =
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(num_pix < 320 * 200) && (cache_bits > 0) ? 1 : 0;
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VP8LBackwardRefs* const refs_trace = refs_array[1];
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VP8LBackwardRefs* const refs_trace = &refs_array[1];
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ClearBackwardRefs(refs_trace);
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if (BackwardReferencesTraceBackwards(width, height, recursion_level, argb,
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quality, cache_bits, hash_chain,
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@ -808,7 +875,6 @@ VP8LBackwardRefs* VP8LGetBackwardReferences(
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if (use_2d_locality) BackwardReferences2DLocality(width, best);
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End:
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return best;
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}
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@ -818,13 +884,13 @@ static double ComputeCacheEntropy(const uint32_t* const argb,
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const VP8LBackwardRefs* const refs,
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int cache_bits) {
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int pixel_index = 0;
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int i;
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uint32_t k;
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const int use_color_cache = (cache_bits > 0);
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int cc_init = 0;
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double entropy = MAX_ENTROPY;
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const double kSmallPenaltyForLargeCache = 4.0;
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VP8LColorCache hashers;
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VP8LRefsCursor c = VP8LRefsCursorInit(refs);
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VP8LHistogram* histo = VP8LAllocateHistogram(cache_bits);
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if (histo == NULL) goto Error;
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@ -833,8 +899,8 @@ static double ComputeCacheEntropy(const uint32_t* const argb,
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if (!cc_init) goto Error;
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}
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for (i = 0; i < refs->size; ++i) {
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const PixOrCopy* const v = &refs->refs[i];
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while (VP8LRefsCursorOk(&c)) {
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const PixOrCopy* const v = c.cur_pos;
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if (PixOrCopyIsLiteral(v)) {
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if (use_color_cache &&
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VP8LColorCacheContains(&hashers, argb[pixel_index])) {
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@ -854,6 +920,7 @@ static double ComputeCacheEntropy(const uint32_t* const argb,
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}
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}
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pixel_index += PixOrCopyLength(v);
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VP8LRefsCursorNext(&c);
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}
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assert(pixel_index == xsize * ysize);
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(void)xsize; // xsize is not used in non-debug compilations otherwise.
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@ -872,7 +939,6 @@ int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
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VP8LHashChain* const hash_chain,
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VP8LBackwardRefs* const refs,
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int* const best_cache_bits) {
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int ok = 0;
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int eval_low = 1;
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int eval_high = 1;
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double entropy_low = MAX_ENTROPY;
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@ -880,10 +946,9 @@ int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
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int cache_bits_low = 0;
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int cache_bits_high = MAX_COLOR_CACHE_BITS;
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ClearBackwardRefs(refs);
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||||
if (!BackwardReferencesHashChain(xsize, ysize, argb, 0, quality, hash_chain,
|
||||
refs)) {
|
||||
goto Error;
|
||||
return 0;
|
||||
}
|
||||
// Do a binary search to find the optimal entropy for cache_bits.
|
||||
while (cache_bits_high - cache_bits_low > 1) {
|
||||
@ -907,7 +972,5 @@ int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
|
||||
eval_high = 1;
|
||||
}
|
||||
}
|
||||
ok = 1;
|
||||
Error:
|
||||
return ok;
|
||||
return 1;
|
||||
}
|
||||
|
@ -113,7 +113,7 @@ static WEBP_INLINE uint32_t PixOrCopyDistance(const PixOrCopy* const p) {
|
||||
}
|
||||
|
||||
// -----------------------------------------------------------------------------
|
||||
// VP8LBackwardRefs
|
||||
// VP8LHashChain
|
||||
|
||||
#define HASH_BITS 18
|
||||
#define HASH_SIZE (1 << HASH_BITS)
|
||||
@ -134,24 +134,58 @@ struct VP8LHashChain {
|
||||
int VP8LHashChainInit(VP8LHashChain* const p, int size);
|
||||
void VP8LHashChainClear(VP8LHashChain* const p); // release memory
|
||||
|
||||
// -----------------------------------------------------------------------------
|
||||
// VP8LBackwardRefs (block-based backward-references storage)
|
||||
|
||||
// maximum number of reference blocks the image will be segmented into
|
||||
#define MAX_REFS_BLOCK_PER_IMAGE 16
|
||||
|
||||
typedef struct PixOrCopyBlock PixOrCopyBlock; // forward declaration
|
||||
typedef struct VP8LBackwardRefs VP8LBackwardRefs;
|
||||
|
||||
// Container for blocks chain
|
||||
struct VP8LBackwardRefs {
|
||||
PixOrCopy* refs;
|
||||
int size; // currently used
|
||||
int max_size; // maximum capacity
|
||||
int block_size_; // common block-size
|
||||
int error_; // set to true if some memory error occurred
|
||||
PixOrCopyBlock* refs_; // list of currently used blocks
|
||||
PixOrCopyBlock** tail_; // for list recycling
|
||||
PixOrCopyBlock* free_blocks_; // free-list
|
||||
PixOrCopyBlock* last_block_; // used for adding new refs (internal)
|
||||
};
|
||||
|
||||
// Release backward references. 'refs' can be NULL.
|
||||
void VP8LBackwardRefsDelete(VP8LBackwardRefs* const refs);
|
||||
|
||||
// Allocate 'max_size' references. Returns NULL in case of memory error.
|
||||
VP8LBackwardRefs* VP8LBackwardRefsNew(int max_size);
|
||||
|
||||
// Copies the 'src' backward refs to the 'dst'. Returns 0 if there's mismatch
|
||||
// in the capacity (max_size) of 'src' and 'dst' refs.
|
||||
// Initialize the object. 'block_size' is the common block size to store
|
||||
// references (typically, width * height / MAX_REFS_BLOCK_PER_IMAGE).
|
||||
void VP8LBackwardRefsInit(VP8LBackwardRefs* const refs, int block_size);
|
||||
// Release memory for backward references.
|
||||
void VP8LBackwardRefsClear(VP8LBackwardRefs* const refs);
|
||||
// Copies the 'src' backward refs to the 'dst'. Returns 0 in case of error.
|
||||
int VP8LBackwardRefsCopy(const VP8LBackwardRefs* const src,
|
||||
VP8LBackwardRefs* const dst);
|
||||
|
||||
// Cursor for iterating on references content
|
||||
typedef struct {
|
||||
// public:
|
||||
PixOrCopy* cur_pos; // current position
|
||||
// private:
|
||||
PixOrCopyBlock* cur_block_; // current block in the refs list
|
||||
const PixOrCopy* last_pos_; // sentinel for switching to next block
|
||||
} VP8LRefsCursor;
|
||||
|
||||
// Returns a cursor positioned at the beginning of the references list.
|
||||
VP8LRefsCursor VP8LRefsCursorInit(const VP8LBackwardRefs* const refs);
|
||||
// Returns true if cursor is pointing at a valid position.
|
||||
static WEBP_INLINE int VP8LRefsCursorOk(const VP8LRefsCursor* const c) {
|
||||
return (c->cur_pos != NULL);
|
||||
}
|
||||
// Move to next block of references. Internal, not to be called directly.
|
||||
void VP8LRefsCursorNextBlock(VP8LRefsCursor* const c);
|
||||
// Move to next position, or NULL. Should not be called if !VP8LRefsCursorOk().
|
||||
static WEBP_INLINE void VP8LRefsCursorNext(VP8LRefsCursor* const c) {
|
||||
assert(c != NULL);
|
||||
assert(VP8LRefsCursorOk(c));
|
||||
if (++c->cur_pos == c->last_pos_) VP8LRefsCursorNextBlock(c);
|
||||
}
|
||||
|
||||
// -----------------------------------------------------------------------------
|
||||
// Main entry points
|
||||
|
||||
@ -162,7 +196,7 @@ int VP8LBackwardRefsCopy(const VP8LBackwardRefs* const src,
|
||||
VP8LBackwardRefs* VP8LGetBackwardReferences(
|
||||
int width, int height, const uint32_t* const argb, int quality,
|
||||
int cache_bits, int use_2d_locality, VP8LHashChain* const hash_chain,
|
||||
VP8LBackwardRefs* const refs[2]);
|
||||
VP8LBackwardRefs refs[2]);
|
||||
|
||||
// Produce an estimate for a good color cache size for the image.
|
||||
int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
|
||||
|
@ -64,9 +64,10 @@ void VP8LFreeHistogramSet(VP8LHistogramSet* const histo) {
|
||||
|
||||
void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
|
||||
VP8LHistogram* const histo) {
|
||||
int i;
|
||||
for (i = 0; i < refs->size; ++i) {
|
||||
VP8LHistogramAddSinglePixOrCopy(histo, &refs->refs[i]);
|
||||
VP8LRefsCursor c = VP8LRefsCursorInit(refs);
|
||||
while (VP8LRefsCursorOk(&c)) {
|
||||
VP8LHistogramAddSinglePixOrCopy(histo, c.cur_pos);
|
||||
VP8LRefsCursorNext(&c);
|
||||
}
|
||||
}
|
||||
|
||||
@ -423,14 +424,14 @@ static int GetHistoBinIndex(
|
||||
static void HistogramBuild(
|
||||
int xsize, int histo_bits, const VP8LBackwardRefs* const backward_refs,
|
||||
VP8LHistogramSet* const init_histo) {
|
||||
int i;
|
||||
int x = 0, y = 0;
|
||||
const int histo_xsize = VP8LSubSampleSize(xsize, histo_bits);
|
||||
VP8LHistogram** const histograms = init_histo->histograms;
|
||||
VP8LRefsCursor c = VP8LRefsCursorInit(backward_refs);
|
||||
assert(histo_bits > 0);
|
||||
// Construct the Histo from a given backward references.
|
||||
for (i = 0; i < backward_refs->size; ++i) {
|
||||
const PixOrCopy* const v = &backward_refs->refs[i];
|
||||
while (VP8LRefsCursorOk(&c)) {
|
||||
const PixOrCopy* const v = c.cur_pos;
|
||||
const int ix = (y >> histo_bits) * histo_xsize + (x >> histo_bits);
|
||||
VP8LHistogramAddSinglePixOrCopy(histograms[ix], v);
|
||||
x += PixOrCopyLength(v);
|
||||
@ -438,6 +439,7 @@ static void HistogramBuild(
|
||||
x -= xsize;
|
||||
++y;
|
||||
}
|
||||
VP8LRefsCursorNext(&c);
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -140,6 +140,9 @@ static int AnalyzeAndInit(VP8LEncoder* const enc, WebPImageHint image_hint) {
|
||||
const int width = pic->width;
|
||||
const int height = pic->height;
|
||||
const int pix_cnt = width * height;
|
||||
// we round the block size up, so we're guaranteed to have
|
||||
// at max MAX_REFS_BLOCK_PER_IMAGE blocks used:
|
||||
int refs_block_size = (pix_cnt - 1) / MAX_REFS_BLOCK_PER_IMAGE + 1;
|
||||
assert(pic != NULL && pic->argb != NULL);
|
||||
|
||||
enc->use_palette_ =
|
||||
@ -169,11 +172,11 @@ static int AnalyzeAndInit(VP8LEncoder* const enc, WebPImageHint image_hint) {
|
||||
}
|
||||
if (!VP8LHashChainInit(&enc->hash_chain_, pix_cnt)) return 0;
|
||||
|
||||
enc->refs_[0] = VP8LBackwardRefsNew(pix_cnt);
|
||||
enc->refs_[1] = VP8LBackwardRefsNew(pix_cnt);
|
||||
if (enc->refs_[0] == NULL || enc->refs_[1] == NULL) {
|
||||
return 0;
|
||||
}
|
||||
// palette-friendly input typically uses less literals
|
||||
// -> reduce block size a bit
|
||||
if (enc->use_palette_) refs_block_size /= 2;
|
||||
VP8LBackwardRefsInit(&enc->refs_[0], refs_block_size);
|
||||
VP8LBackwardRefsInit(&enc->refs_[1], refs_block_size);
|
||||
|
||||
return 1;
|
||||
}
|
||||
@ -425,16 +428,16 @@ static void WriteHuffmanCode(VP8LBitWriter* const bw,
|
||||
|
||||
static void StoreImageToBitMask(
|
||||
VP8LBitWriter* const bw, int width, int histo_bits,
|
||||
const VP8LBackwardRefs* const refs,
|
||||
VP8LBackwardRefs* const refs,
|
||||
const uint16_t* histogram_symbols,
|
||||
const HuffmanTreeCode* const huffman_codes) {
|
||||
// x and y trace the position in the image.
|
||||
int x = 0;
|
||||
int y = 0;
|
||||
const int histo_xsize = histo_bits ? VP8LSubSampleSize(width, histo_bits) : 1;
|
||||
int i;
|
||||
for (i = 0; i < refs->size; ++i) {
|
||||
const PixOrCopy* const v = &refs->refs[i];
|
||||
VP8LRefsCursor c = VP8LRefsCursorInit(refs);
|
||||
while (VP8LRefsCursorOk(&c)) {
|
||||
const PixOrCopy* const v = c.cur_pos;
|
||||
const int histogram_ix = histogram_symbols[histo_bits ?
|
||||
(y >> histo_bits) * histo_xsize +
|
||||
(x >> histo_bits) : 0];
|
||||
@ -468,6 +471,7 @@ static void StoreImageToBitMask(
|
||||
x -= width;
|
||||
++y;
|
||||
}
|
||||
VP8LRefsCursorNext(&c);
|
||||
}
|
||||
}
|
||||
|
||||
@ -475,7 +479,7 @@ static void StoreImageToBitMask(
|
||||
static int EncodeImageNoHuffman(VP8LBitWriter* const bw,
|
||||
const uint32_t* const argb,
|
||||
VP8LHashChain* const hash_chain,
|
||||
VP8LBackwardRefs* const refs_array[2],
|
||||
VP8LBackwardRefs refs_array[2],
|
||||
int width, int height, int quality) {
|
||||
int i;
|
||||
int ok = 0;
|
||||
@ -540,7 +544,7 @@ static int EncodeImageNoHuffman(VP8LBitWriter* const bw,
|
||||
static int EncodeImageInternal(VP8LBitWriter* const bw,
|
||||
const uint32_t* const argb,
|
||||
VP8LHashChain* const hash_chain,
|
||||
VP8LBackwardRefs* const refs_array[2],
|
||||
VP8LBackwardRefs refs_array[2],
|
||||
int width, int height, int quality,
|
||||
int cache_bits, int histogram_bits) {
|
||||
int ok = 0;
|
||||
@ -556,7 +560,7 @@ static int EncodeImageInternal(VP8LBitWriter* const bw,
|
||||
HuffmanTree* huff_tree = NULL;
|
||||
HuffmanTreeToken* tokens = NULL;
|
||||
HuffmanTreeCode* huffman_codes = NULL;
|
||||
VP8LBackwardRefs* refs = NULL;
|
||||
VP8LBackwardRefs refs;
|
||||
VP8LBackwardRefs* best_refs;
|
||||
uint16_t* const histogram_symbols =
|
||||
(uint16_t*)WebPSafeMalloc(histogram_image_xysize,
|
||||
@ -564,28 +568,24 @@ static int EncodeImageInternal(VP8LBitWriter* const bw,
|
||||
assert(histogram_bits >= MIN_HUFFMAN_BITS);
|
||||
assert(histogram_bits <= MAX_HUFFMAN_BITS);
|
||||
|
||||
VP8LBackwardRefsInit(&refs, refs_array[0].block_size_);
|
||||
if (histogram_image == NULL || histogram_symbols == NULL) {
|
||||
VP8LFreeHistogramSet(histogram_image);
|
||||
WebPSafeFree(histogram_symbols);
|
||||
return 0;
|
||||
}
|
||||
|
||||
refs = VP8LBackwardRefsNew(refs_array[0]->max_size);
|
||||
if (refs == NULL) {
|
||||
goto Error;
|
||||
}
|
||||
|
||||
// 'best_refs' is the reference to the best backward refs and points to one
|
||||
// of refs_array[0] or refs_array[1].
|
||||
// Calculate backward references from ARGB image.
|
||||
best_refs = VP8LGetBackwardReferences(width, height, argb, quality,
|
||||
cache_bits, use_2d_locality,
|
||||
hash_chain, refs_array);
|
||||
if (best_refs == NULL || !VP8LBackwardRefsCopy(best_refs, refs)) {
|
||||
if (best_refs == NULL || !VP8LBackwardRefsCopy(best_refs, &refs)) {
|
||||
goto Error;
|
||||
}
|
||||
// Build histogram image and symbols from backward references.
|
||||
if (!VP8LGetHistoImageSymbols(width, height, refs,
|
||||
if (!VP8LGetHistoImageSymbols(width, height, &refs,
|
||||
quality, histogram_bits, cache_bits,
|
||||
histogram_image,
|
||||
histogram_symbols)) {
|
||||
@ -665,7 +665,7 @@ static int EncodeImageInternal(VP8LBitWriter* const bw,
|
||||
}
|
||||
|
||||
// Store actual literals.
|
||||
StoreImageToBitMask(bw, width, histogram_bits, refs,
|
||||
StoreImageToBitMask(bw, width, histogram_bits, &refs,
|
||||
histogram_symbols, huffman_codes);
|
||||
ok = 1;
|
||||
|
||||
@ -673,7 +673,7 @@ static int EncodeImageInternal(VP8LBitWriter* const bw,
|
||||
WebPSafeFree(tokens);
|
||||
WebPSafeFree(huff_tree);
|
||||
VP8LFreeHistogramSet(histogram_image);
|
||||
VP8LBackwardRefsDelete(refs);
|
||||
VP8LBackwardRefsClear(&refs);
|
||||
if (huffman_codes != NULL) {
|
||||
WebPSafeFree(huffman_codes->codes);
|
||||
WebPSafeFree(huffman_codes);
|
||||
@ -740,7 +740,8 @@ static int ApplyPredictFilter(const VP8LEncoder* const enc,
|
||||
VP8LWriteBits(bw, 3, pred_bits - 2);
|
||||
if (!EncodeImageNoHuffman(bw, enc->transform_data_,
|
||||
(VP8LHashChain*)&enc->hash_chain_,
|
||||
enc->refs_, transform_width, transform_height,
|
||||
(VP8LBackwardRefs*)enc->refs_, // cast const away
|
||||
transform_width, transform_height,
|
||||
quality)) {
|
||||
return 0;
|
||||
}
|
||||
@ -762,7 +763,8 @@ static int ApplyCrossColorFilter(const VP8LEncoder* const enc,
|
||||
VP8LWriteBits(bw, 3, ccolor_transform_bits - 2);
|
||||
if (!EncodeImageNoHuffman(bw, enc->transform_data_,
|
||||
(VP8LHashChain*)&enc->hash_chain_,
|
||||
enc->refs_, transform_width, transform_height,
|
||||
(VP8LBackwardRefs*)enc->refs_, // cast const away
|
||||
transform_width, transform_height,
|
||||
quality)) {
|
||||
return 0;
|
||||
}
|
||||
@ -1029,8 +1031,8 @@ static VP8LEncoder* VP8LEncoderNew(const WebPConfig* const config,
|
||||
static void VP8LEncoderDelete(VP8LEncoder* enc) {
|
||||
if (enc != NULL) {
|
||||
VP8LHashChainClear(&enc->hash_chain_);
|
||||
VP8LBackwardRefsDelete(enc->refs_[0]);
|
||||
VP8LBackwardRefsDelete(enc->refs_[1]);
|
||||
VP8LBackwardRefsClear(&enc->refs_[0]);
|
||||
VP8LBackwardRefsClear(&enc->refs_[1]);
|
||||
WebPSafeFree(enc->argb_);
|
||||
WebPSafeFree(enc);
|
||||
}
|
||||
@ -1114,7 +1116,7 @@ WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
|
||||
if (enc->cache_bits_ > 0) {
|
||||
if (!VP8LCalculateEstimateForCacheSize(enc->argb_, enc->current_width_,
|
||||
height, quality, &enc->hash_chain_,
|
||||
enc->refs_[0], &enc->cache_bits_)) {
|
||||
&enc->refs_[0], &enc->cache_bits_)) {
|
||||
err = VP8_ENC_ERROR_INVALID_CONFIGURATION;
|
||||
goto Error;
|
||||
}
|
||||
|
@ -48,10 +48,10 @@ typedef struct {
|
||||
uint32_t palette_[MAX_PALETTE_SIZE];
|
||||
|
||||
// Some 'scratch' (potentially large) objects.
|
||||
struct VP8LBackwardRefs* refs_[2]; // Backward Refs array corresponding to
|
||||
// LZ77 & RLE coding.
|
||||
VP8LHashChain hash_chain_; // HashChain data for constructing
|
||||
// backward references.
|
||||
struct VP8LBackwardRefs refs_[2]; // Backward Refs array corresponding to
|
||||
// LZ77 & RLE coding.
|
||||
VP8LHashChain hash_chain_; // HashChain data for constructing
|
||||
// backward references.
|
||||
} VP8LEncoder;
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
Loading…
Reference in New Issue
Block a user