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Split cost-based backward references in its own file.

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Change-Id: I4d8281e69b0e41f7c90337e5be70a6c65b044086
This commit is contained in:
Vincent Rabaud
2017-06-01 15:07:28 +02:00
parent 498cad34be
commit b903b80c30
8 changed files with 838 additions and 790 deletions
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27
src/enc/backward_references_enc.h
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@ -113,6 +113,15 @@ static WEBP_INLINE uint32_t PixOrCopyDistance(const PixOrCopy* const p) {
#define HASH_BITS 18
#define HASH_SIZE (1 << HASH_BITS)
// If you change this, you need MAX_LENGTH_BITS + WINDOW_SIZE_BITS <= 32 as it
// is used in VP8LHashChain.
#define MAX_LENGTH_BITS 12
// We want the max value to be attainable and stored in MAX_LENGTH_BITS bits.
#define MAX_LENGTH ((1 << MAX_LENGTH_BITS) - 1)
#if MAX_LENGTH_BITS + WINDOW_SIZE_BITS > 32
#error "MAX_LENGTH_BITS + WINDOW_SIZE_BITS > 32"
#endif
typedef struct VP8LHashChain VP8LHashChain;
struct VP8LHashChain {
// The 20 most significant bits contain the offset at which the best match
@ -134,6 +143,24 @@ int VP8LHashChainFill(VP8LHashChain* const p, int quality,
int low_effort);
void VP8LHashChainClear(VP8LHashChain* const p); // release memory
static WEBP_INLINE int VP8LHashChainFindOffset(const VP8LHashChain* const p,
const int base_position) {
return p->offset_length_[base_position] >> MAX_LENGTH_BITS;
}
static WEBP_INLINE int VP8LHashChainFindLength(const VP8LHashChain* const p,
const int base_position) {
return p->offset_length_[base_position] & ((1U << MAX_LENGTH_BITS) - 1);
}
static WEBP_INLINE void VP8LHashChainFindCopy(const VP8LHashChain* const p,
int base_position,
int* const offset_ptr,
int* const length_ptr) {
*offset_ptr = VP8LHashChainFindOffset(p, base_position);
*length_ptr = VP8LHashChainFindLength(p, base_position);
}
// -----------------------------------------------------------------------------
// VP8LBackwardRefs (block-based backward-references storage)