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123 lines
5.8 KiB
C
123 lines
5.8 KiB
C
/* ******************************************************************
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Huff0 : Huffman coder, part of New Generation Entropy library
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header file for static linking (only)
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Copyright (C) 2013-2015, Yann Collet
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following disclaimer
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in the documentation and/or other materials provided with the
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distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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You can contact the author at :
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- Source repository : https://github.com/Cyan4973/FiniteStateEntropy
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- Public forum : https://groups.google.com/forum/#!forum/lz4c
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****************************************************************** */
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#ifndef HUFF0_STATIC_H
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#define HUFF0_STATIC_H
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#if defined (__cplusplus)
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extern "C" {
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#endif
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/* ****************************************
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* Dependency
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******************************************/
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#include "huff0.h"
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/* ****************************************
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* Static allocation macros
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******************************************/
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/* Huff0 buffer bounds */
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#define HUF_CTABLEBOUND 129
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#define HUF_BLOCKBOUND(size) (size + (size>>8) + 8) /* only true if incompressible pre-filtered with fast heuristic */
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#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
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/* static allocation of Huff0's DTable */
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#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1<<maxTableLog)) /* nb Cells; use unsigned short for X2, unsigned int for X4 */
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#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
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unsigned short DTable[HUF_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
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#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) \
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unsigned int DTable[HUF_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
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#define HUF_CREATE_STATIC_DTABLEX6(DTable, maxTableLog) \
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unsigned int DTable[HUF_DTABLE_SIZE(maxTableLog) * 3 / 2] = { maxTableLog }
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/* ****************************************
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* Advanced decompression functions
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******************************************/
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size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* single-symbol decoder */
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size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* double-symbols decoder */
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size_t HUF_decompress4X6 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* quad-symbols decoder */
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/* ****************************************
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* Huff0 detailed API
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******************************************/
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/*!
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HUF_compress() does the following:
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1. count symbol occurrence from source[] into table count[] using FSE_count()
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2. build Huffman table from count using HUF_buildCTable()
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3. save Huffman table to memory buffer using HUF_writeCTable()
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4. encode the data stream using HUF_compress_usingCTable()
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The following API allows targeting specific sub-functions for advanced tasks.
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For example, it's possible to compress several blocks using the same 'CTable',
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or to save and regenerate 'CTable' using external methods.
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*/
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/* FSE_count() : find it within "fse.h" */
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typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */
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size_t HUF_buildCTable (HUF_CElt* tree, const unsigned* count, unsigned maxSymbolValue, unsigned maxNbBits);
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size_t HUF_writeCTable (void* dst, size_t maxDstSize, const HUF_CElt* tree, unsigned maxSymbolValue, unsigned huffLog);
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size_t HUF_compress_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
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/*!
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HUF_decompress() does the following:
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1. select the decompression algorithm (X2, X4, X6) based on pre-computed heuristics
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2. build Huffman table from save, using HUF_readDTableXn()
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3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable
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*/
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size_t HUF_readDTableX2 (unsigned short* DTable, const void* src, size_t srcSize);
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size_t HUF_readDTableX4 (unsigned* DTable, const void* src, size_t srcSize);
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size_t HUF_readDTableX6 (unsigned* DTable, const void* src, size_t srcSize);
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size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* single-symbol decoder */
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size_t HUF_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* double-symbol decoder */
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size_t HUF_decompress1X6 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /* quad-symbol decoder */
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size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned short* DTable);
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size_t HUF_decompress4X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned* DTable);
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size_t HUF_decompress4X6_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned* DTable);
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#if defined (__cplusplus)
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}
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#endif
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#endif /* HUFF0_STATIC_H */
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