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229 lines
11 KiB
C
229 lines
11 KiB
C
/* ******************************************************************
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Huffman coder, part of New Generation Entropy library
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header file
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Copyright (C) 2013-2016, 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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****************************************************************** */
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#ifndef HUF_H_298734234
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#define HUF_H_298734234
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#if defined (__cplusplus)
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extern "C" {
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#endif
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/* *** Dependencies *** */
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#include <stddef.h> /* size_t */
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/* *** simple functions *** */
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/**
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HUF_compress() :
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Compress content from buffer 'src', of size 'srcSize', into buffer 'dst'.
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'dst' buffer must be already allocated.
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Compression runs faster if `dstCapacity` >= HUF_compressBound(srcSize).
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`srcSize` must be <= `HUF_BLOCKSIZE_MAX` == 128 KB.
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@return : size of compressed data (<= `dstCapacity`).
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Special values : if return == 0, srcData is not compressible => Nothing is stored within dst !!!
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if return == 1, srcData is a single repeated byte symbol (RLE compression).
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if HUF_isError(return), compression failed (more details using HUF_getErrorName())
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*/
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size_t HUF_compress(void* dst, size_t dstCapacity,
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const void* src, size_t srcSize);
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/**
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HUF_decompress() :
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Decompress HUF data from buffer 'cSrc', of size 'cSrcSize',
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into already allocated buffer 'dst', of minimum size 'dstSize'.
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`dstSize` : **must** be the ***exact*** size of original (uncompressed) data.
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Note : in contrast with FSE, HUF_decompress can regenerate
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RLE (cSrcSize==1) and uncompressed (cSrcSize==dstSize) data,
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because it knows size to regenerate.
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@return : size of regenerated data (== dstSize),
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or an error code, which can be tested using HUF_isError()
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*/
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size_t HUF_decompress(void* dst, size_t dstSize,
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const void* cSrc, size_t cSrcSize);
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/* ****************************************
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* Tool functions
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******************************************/
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#define HUF_BLOCKSIZE_MAX (128 * 1024)
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size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */
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/* Error Management */
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unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */
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const char* HUF_getErrorName(size_t code); /**< provides error code string (useful for debugging) */
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/* *** Advanced function *** */
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/** HUF_compress2() :
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* Same as HUF_compress(), but offers direct control over `maxSymbolValue` and `tableLog` */
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size_t HUF_compress2 (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog);
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#ifdef HUF_STATIC_LINKING_ONLY
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/* *** Dependencies *** */
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#include "mem.h" /* U32 */
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/* *** Constants *** */
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#define HUF_TABLELOG_ABSOLUTEMAX 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
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#define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
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#define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */
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#define HUF_SYMBOLVALUE_MAX 255
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#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
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# error "HUF_TABLELOG_MAX is too large !"
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#endif
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/* ****************************************
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* Static allocation
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******************************************/
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/* HUF 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 HUF's Compression Table */
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#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
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U32 name##hb[maxSymbolValue+1]; \
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void* name##hv = &(name##hb); \
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HUF_CElt* name = (HUF_CElt*)(name##hv) /* no final ; */
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/* static allocation of HUF's DTable */
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typedef U32 HUF_DTable;
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#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1<<(maxTableLog)))
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#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
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HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1)*0x1000001) }
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#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) \
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HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog)*0x1000001) }
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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_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< decodes RLE and uncompressed */
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size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< considers RLE and uncompressed as errors */
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size_t HUF_decompress4X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< single-symbol decoder */
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size_t HUF_decompress4X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< double-symbols decoder */
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size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
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size_t HUF_decompress1X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< single-symbol decoder */
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size_t HUF_decompress1X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< double-symbols decoder */
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/* ****************************************
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* HUF 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. (optional) refine tableLog using HUF_optimalTableLog()
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3. build Huffman table from count using HUF_buildCTable()
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4. save Huffman table to memory buffer using HUF_writeCTable()
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5. encode the data stream using HUF_compress4X_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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unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
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typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */
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size_t HUF_buildCTable (HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue, unsigned maxNbBits);
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size_t HUF_writeCTable (void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog);
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size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
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/*! HUF_readStats() :
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Read compact Huffman tree, saved by HUF_writeCTable().
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`huffWeight` is destination buffer.
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@return : size read from `src` , or an error Code .
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Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
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size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
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U32* nbSymbolsPtr, U32* tableLogPtr,
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const void* src, size_t srcSize);
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/** HUF_readCTable() :
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* Loading a CTable saved with HUF_writeCTable() */
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size_t HUF_readCTable (HUF_CElt* CTable, unsigned maxSymbolValue, const void* src, size_t srcSize);
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/*
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HUF_decompress() does the following:
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1. select the decompression algorithm (X2, X4) 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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/** HUF_selectDecoder() :
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* Tells which decoder is likely to decode faster,
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* based on a set of pre-determined metrics.
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* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 .
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* Assumption : 0 < cSrcSize < dstSize <= 128 KB */
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U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);
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size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize);
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size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize);
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size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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size_t HUF_decompress4X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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/* single stream variants */
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size_t HUF_compress1X (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog);
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size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
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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_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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size_t HUF_decompress1X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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size_t HUF_decompress1X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
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#endif /* HUF_STATIC_LINKING_ONLY */
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#if defined (__cplusplus)
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}
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#endif
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#endif /* HUF_H_298734234 */
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