Visible to Intel only — GUID: GUID-E6EAF5E0-D344-44DC-AF98-9FBDA28EDEE9
Visible to Intel only — GUID: GUID-E6EAF5E0-D344-44DC-AF98-9FBDA28EDEE9
DeflateLZ77
Performs LZ77 encoding according to the specified compression level.
Syntax
IppStatus ippsDeflateLZ77_8u(const Ipp8u** ppSrc, Ipp32u* pSrcLen, Ipp32u* pSrcIdx, const Ipp8u* pWindow, Ipp32u winSize, Ipp32s* pHashHead, Ipp32s* pHashPrev, Ipp32u hashSize, IppDeflateFreqTable pLitFreqTable[286], IppDeflateFreqTable pDistFreqTable[30], Ipp8u* pLitDst, Ipp16u* pDistDst, Ipp32u* pDstLen, int comprLevel, IppLZ77Flush flush);
Include Files
ippdc.h
Domain Dependencies
Headers: ippcore.h, ippvm.h, ipps.h
Libraries: ippcore.lib, ippvm.lib, ipps.lib
Parameters
ppSrc |
Double pointer to the source vector. |
pSrcLen |
Pointer to the length of the source vector. |
pSrcIdx |
Pointer to the index of the current position in the source vector. |
pWindow |
Pointer to the sliding window (the dictionary for the LZ77 algorithm). |
winSize |
Size of the sliding window and the pHashPrev table. |
pHashHead |
Pointer to the table containing heads of the hash chains. |
pHashPrev |
Pointer to the table contating indexes to the previous strings with the same hash key. |
hashSize |
Size of the pHashHead table. |
pLitFreqTable |
Pointer to the literals/lengths frequency table. |
pDistFreqTable |
Pointer to the distances frequency table. |
pLitDst |
Pointer to the destination vector containing literals/lengths. |
pDistDst |
Pointer to the destination vector containing distances. |
pDstLen |
Pointer to the length of the destination vectors. |
comprLevel |
Compression level in range [0..9] in accordance with ZLIB. |
flush |
Specifies the encoding mode for data blocks (see flush parameter). |
Description
This function performs LZ77 encoding of source data ppSrc according to the compression level comprLevel, which is similar to the ZLIB compression level.
To correctly process the first bytes of the source vector, initialize the pHashHead table with the winSize value.
The pSrcIdx parameter returns the index of the current position in the source vector, and is used to establish a correlation between the current position in the source vector and indexes in hash tables. After processing each 2GB of source data, the index and hash tables must be normalized (instead of 64K of source data in ZLIB).
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when at least one of the specified pointers is NULL. |