/* Lzma86Enc.h -- LZMA + x86 (BCJ) Filter Encoder
2008-08-05
Igor Pavlov
Public domain */
#ifndef __LZMA86ENC_H
#define __LZMA86ENC_H
#include "Types.h"
/*
It's an example for LZMA + x86 Filter use.
You can use .lzma86 extension, if you write that stream to file.
.lzma86 header adds one additional byte to standard .lzma header.
.lzma86 header (14 bytes):
Offset Size Description
0 1 = 0 - no filter,
= 1 - x86 filter
1 1 lc, lp and pb in encoded form
2 4 dictSize (little endian)
6 8 uncompressed size (little endian)
Lzma86_Encode
-------------
level - compression level: 0 <= level <= 9, the default value for "level" is 5.
dictSize - The dictionary size in bytes. The maximum value is
128 MB = (1 << 27) bytes for 32-bit version
1 GB = (1 << 30) bytes for 64-bit version
The default value is 16 MB = (1 << 24) bytes, for level = 5.
It's recommended to use the dictionary that is larger than 4 KB and
that can be calculated as (1 << N) or (3 << N) sizes.
For better compression ratio dictSize must be >= inSize.
filterMode:
SZ_FILTER_NO - no Filter
SZ_FILTER_YES - x86 Filter
SZ_FILTER_AUTO - it tries both alternatives to select best.
Encoder will use 2 or 3 passes:
2 passes when FILTER_NO provides better compression.
3 passes when FILTER_YES provides better compression.
Lzma86Encode allocates Data with MyAlloc functions.
RAM Requirements for compressing:
RamSize = dictionarySize * 11.5 + 6MB + FilterBlockSize
filterMode FilterBlockSize
SZ_FILTER_NO 0
SZ_FILTER_YES inSize
SZ_FILTER_AUTO inSize
Return code:
SZ_OK - OK
SZ_ERROR_MEM - Memory allocation error
SZ_ERROR_PARAM - Incorrect paramater
SZ_ERROR_OUTPUT_EOF - output buffer overflow
SZ_ERROR_THREAD - errors in multithreading functions (only for Mt version)
*/
enum ESzFilterMode
{
SZ_FILTER_NO,
SZ_FILTER_YES,
SZ_FILTER_AUTO
};
SRes Lzma86_Encode(Byte *dest, size_t *destLen, const Byte *src, size_t srcLen,
int level, UInt32 dictSize, int filterMode);
#endif