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-rw-r--r--src/3rdparty/libwebp/src/enc/backward_references.h18
1 files changed, 11 insertions, 7 deletions
diff --git a/src/3rdparty/libwebp/src/enc/backward_references.h b/src/3rdparty/libwebp/src/enc/backward_references.h
index daa084d..0cadb11 100644
--- a/src/3rdparty/libwebp/src/enc/backward_references.h
+++ b/src/3rdparty/libwebp/src/enc/backward_references.h
@@ -115,11 +115,12 @@ static WEBP_INLINE uint32_t PixOrCopyDistance(const PixOrCopy* const p) {
typedef struct VP8LHashChain VP8LHashChain;
struct VP8LHashChain {
- // Stores the most recently added position with the given hash value.
- int32_t hash_to_first_index_[HASH_SIZE];
- // chain_[pos] stores the previous position with the same hash value
- // for every pixel in the image.
- int32_t* chain_;
+ // The 20 most significant bits contain the offset at which the best match
+ // is found. These 20 bits are the limit defined by GetWindowSizeForHashChain
+ // (through WINDOW_SIZE = 1<<20).
+ // The lower 12 bits contain the length of the match. The 12 bit limit is
+ // defined in MaxFindCopyLength with MAX_LENGTH=4096.
+ uint32_t* offset_length_;
// This is the maximum size of the hash_chain that can be constructed.
// Typically this is the pixel count (width x height) for a given image.
int size_;
@@ -127,6 +128,9 @@ struct VP8LHashChain {
// Must be called first, to set size.
int VP8LHashChainInit(VP8LHashChain* const p, int size);
+// Pre-compute the best matches for argb.
+int VP8LHashChainFill(VP8LHashChain* const p, int quality,
+ const uint32_t* const argb, int xsize, int ysize);
void VP8LHashChainClear(VP8LHashChain* const p); // release memory
// -----------------------------------------------------------------------------
@@ -192,8 +196,8 @@ static WEBP_INLINE void VP8LRefsCursorNext(VP8LRefsCursor* const c) {
// refs[0] or refs[1].
VP8LBackwardRefs* VP8LGetBackwardReferences(
int width, int height, const uint32_t* const argb, int quality,
- int low_effort, int* const cache_bits, VP8LHashChain* const hash_chain,
- VP8LBackwardRefs refs[2]);
+ int low_effort, int* const cache_bits,
+ const VP8LHashChain* const hash_chain, VP8LBackwardRefs refs[2]);
#ifdef __cplusplus
}