/* 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 "zopfli.h" /* 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 unsigned short* litlens, const unsigned short* dists, size_t lstart, size_t lend, int btype); #endif /* ZOPFLI_DEFLATE_H_ */ |