chromium/third_party/brotli/enc/backward_references_hq.h

/* Copyright 2013 Google Inc. All Rights Reserved.

   Distributed under MIT license.
   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/

/* Function to find backward reference copies. */

#ifndef BROTLI_ENC_BACKWARD_REFERENCES_HQ_H_
#define BROTLI_ENC_BACKWARD_REFERENCES_HQ_H_

#include "../common/constants.h"
#include "../common/context.h"
#include "../common/dictionary.h"
#include "../common/platform.h"
#include <brotli/types.h>
#include "command.h"
#include "hash.h"
#include "memory.h"
#include "quality.h"

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

BROTLI_INTERNAL void BrotliCreateZopfliBackwardReferences(MemoryManager* m,
    size_t num_bytes,
    size_t position, const uint8_t* ringbuffer, size_t ringbuffer_mask,
    ContextLut literal_context_lut, const BrotliEncoderParams* params,
    Hasher* hasher, int* dist_cache, size_t* last_insert_len,
    Command* commands, size_t* num_commands, size_t* num_literals);

BROTLI_INTERNAL void BrotliCreateHqZopfliBackwardReferences(MemoryManager* m,
    size_t num_bytes,
    size_t position, const uint8_t* ringbuffer, size_t ringbuffer_mask,
    ContextLut literal_context_lut, const BrotliEncoderParams* params,
    Hasher* hasher, int* dist_cache, size_t* last_insert_len,
    Command* commands, size_t* num_commands, size_t* num_literals);

ZopfliNode;

BROTLI_INTERNAL void BrotliInitZopfliNodes(ZopfliNode* array, size_t length);

/* Computes the shortest path of commands from position to at most
   position + num_bytes.

   On return, path->size() is the number of commands found and path[i] is the
   length of the i-th command (copy length plus insert length).
   Note that the sum of the lengths of all commands can be less than num_bytes.

   On return, the nodes[0..num_bytes] array will have the following
   "ZopfliNode array invariant":
   For each i in [1..num_bytes], if nodes[i].cost < kInfinity, then
     (1) nodes[i].copy_length() >= 2
     (2) nodes[i].command_length() <= i and
     (3) nodes[i - nodes[i].command_length()].cost < kInfinity */
BROTLI_INTERNAL size_t BrotliZopfliComputeShortestPath(
    MemoryManager* m, size_t num_bytes,
    size_t position, const uint8_t* ringbuffer, size_t ringbuffer_mask,
    ContextLut literal_context_lut, const BrotliEncoderParams* params,
    const int* dist_cache, Hasher* hasher, ZopfliNode* nodes);

BROTLI_INTERNAL void BrotliZopfliCreateCommands(
    const size_t num_bytes, const size_t block_start, const ZopfliNode* nodes,
    int* dist_cache, size_t* last_insert_len, const BrotliEncoderParams* params,
    Command* commands, size_t* num_literals);

#if defined(__cplusplus) || defined(c_plusplus)
}  /* extern "C" */
#endif

#endif  /* BROTLI_ENC_BACKWARD_REFERENCES_HQ_H_ */