mirror of
https://github.com/rsms/inter.git
synced 2024-12-14 18:11:35 +03:00
93 lines
3.0 KiB
C
93 lines
3.0 KiB
C
/*
|
|
Copyright 2011 Google Inc. All Rights Reserved.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
Author: lode.vandevenne@gmail.com (Lode Vandevenne)
|
|
Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala)
|
|
*/
|
|
|
|
#ifndef ZOPFLI_DEFLATE_H_
|
|
#define ZOPFLI_DEFLATE_H_
|
|
|
|
/*
|
|
Functions to compress according to the DEFLATE specification, using the
|
|
"squeeze" LZ77 compression backend.
|
|
*/
|
|
|
|
#include "lz77.h"
|
|
#include "zopfli.h"
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/*
|
|
Compresses according to the deflate specification and append the compressed
|
|
result to the output.
|
|
This function will usually output multiple deflate blocks. If final is 1, then
|
|
the final bit will be set on the last block.
|
|
|
|
options: global program options
|
|
btype: the deflate block type. Use 2 for best compression.
|
|
-0: non compressed blocks (00)
|
|
-1: blocks with fixed tree (01)
|
|
-2: blocks with dynamic tree (10)
|
|
final: whether this is the last section of the input, sets the final bit to the
|
|
last deflate block.
|
|
in: the input bytes
|
|
insize: number of input bytes
|
|
bp: bit pointer for the output array. This must initially be 0, and for
|
|
consecutive calls must be reused (it can have values from 0-7). This is
|
|
because deflate appends blocks as bit-based data, rather than on byte
|
|
boundaries.
|
|
out: pointer to the dynamic output array to which the result is appended. Must
|
|
be freed after use.
|
|
outsize: pointer to the dynamic output array size.
|
|
*/
|
|
void ZopfliDeflate(const ZopfliOptions* options, int btype, int final,
|
|
const unsigned char* in, size_t insize,
|
|
unsigned char* bp, unsigned char** out, size_t* outsize);
|
|
|
|
/*
|
|
Like ZopfliDeflate, but allows to specify start and end byte with instart and
|
|
inend. Only that part is compressed, but earlier bytes are still used for the
|
|
back window.
|
|
*/
|
|
void ZopfliDeflatePart(const ZopfliOptions* options, int btype, int final,
|
|
const unsigned char* in, size_t instart, size_t inend,
|
|
unsigned char* bp, unsigned char** out,
|
|
size_t* outsize);
|
|
|
|
/*
|
|
Calculates block size in bits.
|
|
litlens: lz77 lit/lengths
|
|
dists: ll77 distances
|
|
lstart: start of block
|
|
lend: end of block (not inclusive)
|
|
*/
|
|
double ZopfliCalculateBlockSize(const ZopfliLZ77Store* lz77,
|
|
size_t lstart, size_t lend, int btype);
|
|
|
|
/*
|
|
Calculates block size in bits, automatically using the best btype.
|
|
*/
|
|
double ZopfliCalculateBlockSizeAutoType(const ZopfliLZ77Store* lz77,
|
|
size_t lstart, size_t lend);
|
|
|
|
#ifdef __cplusplus
|
|
} // extern "C"
|
|
#endif
|
|
|
|
#endif /* ZOPFLI_DEFLATE_H_ */
|