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      LzmaAlone    - file->file LZMA compression/decompression
      RangeCoder   - Range Coder (special code of compression/decompression)

Java/  - Java files
  SevenZip
    Compression    - files related to compression/decompression
      LZ           - files related to LZ (Lempel-Ziv) compression algorithm
      LZMA         - LZMA compression/decompression
      RangeCoder   - Range Coder (special code of compression/decompression)


C/C++ source code of LZMA SDK is part of 7-Zip project.
7-Zip source code can be downloaded from 7-Zip's SourceForge page:

  http://sourceforge.net/projects/sevenzip/



LZMA features
-------------
  - Variable dictionary size (up to 1 GB)
  - Estimated compressing speed: about 2 MB/s on 2 GHz CPU
  - Estimated decompressing speed: 
      - 20-30 MB/s on 2 GHz Core 2 or AMD Athlon 64
      - 1-2 MB/s on 200 MHz ARM, MIPS, PowerPC or other simple RISC
  - Small memory requirements for decompressing (16 KB + DictionarySize)
  - Small code size for decompressing: 5-8 KB

LZMA decoder uses only integer operations and can be 
implemented in any modern 32-bit CPU (or on 16-bit CPU with some conditions).

Some critical operations that affect the speed of LZMA decompression:
  1) 32*16 bit integer multiply
  2) Misspredicted branches (penalty mostly depends from pipeline length)
  3) 32-bit shift and arithmetic operations

The speed of LZMA decompressing mostly depends from CPU speed.
Memory speed has no big meaning. But if your CPU has small data cache, 
overall weight of memory speed will slightly increase.


How To Use
----------

Using LZMA encoder/decoder executable
--------------------------------------

Usage:  LZMA <e|d> inputFile outputFile [<switches>...]

  e: encode file

  d: decode file

  b: Benchmark. There are two tests: compressing and decompressing 
     with LZMA method. Benchmark shows rating in MIPS (million 
     instructions per second). Rating value is calculated from 
     measured speed and it is normalized with Intel's Core 2 results.
     Also Benchmark checks possible hardware errors (RAM 
     errors in most cases). Benchmark uses these settings:
     (-a1, -d21, -fb32, -mfbt4). You can change only -d parameter. 
     Also you can change the number of iterations. Example for 30 iterations:
       LZMA b 30
     Default number of iterations is 10.

<Switches>
  

  -a{N}:  set compression mode 0 = fast, 1 = normal
          default: 1 (normal)

  d{N}:   Sets Dictionary size - [0, 30], default: 23 (8MB)
          The maximum value for dictionary size is 1 GB = 2^30 bytes.
          Dictionary size is calculated as DictionarySize = 2^N bytes. 
          For decompressing file compressed by LZMA method with dictionary 
          size D = 2^N you need about D bytes of memory (RAM).

  -fb{N}: set number of fast bytes - [5, 273], default: 128
          Usually big number gives a little bit better compression ratio 
          and slower compression process.

  -lc{N}: set number of literal context bits - [0, 8], default: 3
          Sometimes lc=4 gives gain for big files.

  -lp{N}: set number of literal pos bits - [0, 4], default: 0
          lp switch is intended for periodical data when period is 
          equal 2^N. For example, for 32-bit (4 bytes) 
          periodical data you can use lp=2. Often it's better to set lc0, 
          if you change lp switch.

  -pb{N}: set number of pos bits - [0, 4], default: 2
          pb switch is intended for periodical data 
          when period is equal 2^N.

  -mf{MF_ID}: set Match Finder. Default: bt4. 
              Algorithms from hc* group doesn't provide good compression 
              ratio, but they often works pretty fast in combination with 
              fast mode (-a0).

              Memory requirements depend from dictionary size 
              (parameter "d" in table below). 

               MF_ID     Memory                   Description

                bt2    d *  9.5 + 4MB  Binary Tree with 2 bytes hashing.
                bt3    d * 11.5 + 4MB  Binary Tree with 3 bytes hashing.
                bt4    d * 11.5 + 4MB  Binary Tree with 4 bytes hashing.
                hc4    d *  7.5 + 4MB  Hash Chain with 4 bytes hashing.

  -eos:   write End Of Stream marker. By default LZMA doesn't write 
          eos marker, since LZMA decoder knows uncompressed size 
          stored in .lzma file header.

  -si:    Read data from stdin (it will write End Of Stream marker).
  -so:    Write data to stdout


Examples:

1) LZMA e file.bin file.lzma -d16 -lc0 

compresses file.bin to file.lzma with 64 KB dictionary (2^16=64K)  
and 0 literal context bits. -lc0 allows to reduce memory requirements 
for decompression.