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/* 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

               = 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