/* 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