mirror of
https://github.com/google/brotli.git
synced 2024-11-24 20:40:13 +00:00
7f740f1308
- fix formatting - fix type conversion - fix no-op arithmetic with null-pointer - improve performance of hash_longest_match64 - go: detect read after close - java decoder: support compound dictionary - remove executable flag on non-scripts
100 lines
3.5 KiB
C++
100 lines
3.5 KiB
C++
#ifndef BROTLI_RESEARCH_DURCHSCHLAG_H_
|
|
#define BROTLI_RESEARCH_DURCHSCHLAG_H_
|
|
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
/**
|
|
* Generate a dictionary for given samples.
|
|
*
|
|
* @param dictionary_size_limit maximal dictionary size
|
|
* @param slice_len text slice size
|
|
* @param block_len score block length
|
|
* @param sample_sizes vector with sample sizes
|
|
* @param sample_data concatenated samples
|
|
* @return generated dictionary
|
|
*/
|
|
std::string durchschlag_generate(
|
|
size_t dictionary_size_limit, size_t slice_len, size_t block_len,
|
|
const std::vector<size_t>& sample_sizes, const uint8_t* sample_data);
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Lower level API for repetitive dictionary generation.
|
|
//------------------------------------------------------------------------------
|
|
|
|
/* Pointer to position in text. */
|
|
typedef uint32_t DurchschlagTextIdx;
|
|
|
|
/* Context is made public for flexible serialization / deserialization. */
|
|
typedef struct DurchschlagContext {
|
|
DurchschlagTextIdx dataSize;
|
|
DurchschlagTextIdx sliceLen;
|
|
DurchschlagTextIdx numUniqueSlices;
|
|
std::vector<DurchschlagTextIdx> offsets;
|
|
std::vector<DurchschlagTextIdx> sliceMap;
|
|
} DurchschlagContext;
|
|
|
|
DurchschlagContext durchschlag_prepare(size_t slice_len,
|
|
const std::vector<size_t>& sample_sizes, const uint8_t* sample_data);
|
|
|
|
typedef enum DurchschalgResourceStrategy {
|
|
// Faster
|
|
DURCHSCHLAG_EXCLUSIVE = 0,
|
|
// Uses much less memory
|
|
DURCHSCHLAG_COLLABORATIVE = 1
|
|
} DurchschalgResourceStrategy;
|
|
|
|
std::string durchschlag_generate(DurchschalgResourceStrategy strategy,
|
|
size_t dictionary_size_limit, size_t block_len,
|
|
const DurchschlagContext& context, const uint8_t* sample_data);
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Suffix Array based preparation.
|
|
//------------------------------------------------------------------------------
|
|
|
|
typedef struct DurchschlagIndex {
|
|
std::vector<DurchschlagTextIdx> lcp;
|
|
std::vector<DurchschlagTextIdx> sa;
|
|
} DurchschlagIndex;
|
|
|
|
DurchschlagIndex durchschlag_index(const std::vector<uint8_t>& data);
|
|
|
|
DurchschlagContext durchschlag_prepare(size_t slice_len,
|
|
const std::vector<size_t>& sample_sizes, const DurchschlagIndex& index);
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Data preparation.
|
|
//------------------------------------------------------------------------------
|
|
|
|
/**
|
|
* Cut out unique slices.
|
|
*
|
|
* Both @p sample_sizes and @p sample_data are modified in-place. Number of
|
|
* samples remains unchanged, but some samples become shorter.
|
|
*
|
|
* @param slice_len (unique) slice size
|
|
* @param minimum_population minimum non-unique slice occurrence
|
|
* @param sample_sizes [in / out] vector with sample sizes
|
|
* @param sample_data [in / out] concatenated samples
|
|
*/
|
|
void durchschlag_distill(size_t slice_len, size_t minimum_population,
|
|
std::vector<size_t>* sample_sizes, uint8_t* sample_data);
|
|
|
|
/**
|
|
* Replace unique slices with zeroes.
|
|
*
|
|
* @p sample_data is modified in-place. Number of samples and their length
|
|
* remain unchanged.
|
|
*
|
|
* @param slice_len (unique) slice size
|
|
* @param minimum_population minimum non-unique slice occurrence
|
|
* @param sample_sizes vector with sample sizes
|
|
* @param sample_data [in / out] concatenated samples
|
|
*/
|
|
void durchschlag_purify(size_t slice_len, size_t minimum_population,
|
|
const std::vector<size_t>& sample_sizes, uint8_t* sample_data);
|
|
|
|
#endif // BROTLI_RESEARCH_DURCHSCHLAG_H_
|