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diff --git a/BaseTools/Source/C/LzmaCompress/Sdk/DOC/lzma-sdk.txt b/BaseTools/Source/C/LzmaCompress/Sdk/DOC/lzma-sdk.txt deleted file mode 100644 index 86fef248f4..0000000000 --- a/BaseTools/Source/C/LzmaCompress/Sdk/DOC/lzma-sdk.txt +++ /dev/null @@ -1,357 +0,0 @@ -LZMA SDK 16.04
---------------
-
-LZMA SDK provides the documentation, samples, header files,
-libraries, and tools you need to develop applications that
-use 7z / LZMA / LZMA2 / XZ compression.
-
-LZMA is an improved version of famous LZ77 compression algorithm.
-It was improved in way of maximum increasing of compression ratio,
-keeping high decompression speed and low memory requirements for
-decompressing.
-
-LZMA2 is a LZMA based compression method. LZMA2 provides better
-multithreading support for compression than LZMA and some other improvements.
-
-7z is a file format for data compression and file archiving.
-7z is a main file format for 7-Zip compression program (www.7-zip.org).
-7z format supports different compression methods: LZMA, LZMA2 and others.
-7z also supports AES-256 based encryption.
-
-XZ is a file format for data compression that uses LZMA2 compression.
-XZ format provides additional features: SHA/CRC check, filters for
-improved compression ratio, splitting to blocks and streams,
-
-
-
-LICENSE
--------
-
-LZMA SDK is written and placed in the public domain by Igor Pavlov.
-
-Some code in LZMA SDK is based on public domain code from another developers:
- 1) PPMd var.H (2001): Dmitry Shkarin
- 2) SHA-256: Wei Dai (Crypto++ library)
-
-Anyone is free to copy, modify, publish, use, compile, sell, or distribute the
-original LZMA SDK code, either in source code form or as a compiled binary, for
-any purpose, commercial or non-commercial, and by any means.
-
-LZMA SDK code is compatible with open source licenses, for example, you can
-include it to GNU GPL or GNU LGPL code.
-
-
-LZMA SDK Contents
------------------
-
- Source code:
-
- - C / C++ / C# / Java - LZMA compression and decompression
- - C / C++ - LZMA2 compression and decompression
- - C / C++ - XZ compression and decompression
- - C - 7z decompression
- - C++ - 7z compression and decompression
- - C - small SFXs for installers (7z decompression)
- - C++ - SFXs and SFXs for installers (7z decompression)
-
- Precomiled binaries:
-
- - console programs for lzma / 7z / xz compression and decompression
- - SFX modules for installers.
-
-
-UNIX/Linux version
-------------------
-To compile C++ version of file->file LZMA encoding, go to directory
-CPP/7zip/Bundles/LzmaCon
-and call make to recompile it:
- make -f makefile.gcc clean all
-
-In some UNIX/Linux versions you must compile LZMA with static libraries.
-To compile with static libraries, you can use
-LIB = -lm -static
-
-Also you can use p7zip (port of 7-Zip for POSIX systems like Unix or Linux):
-
- http://p7zip.sourceforge.net/
-
-
-Files
------
-
-DOC/7zC.txt - 7z ANSI-C Decoder description
-DOC/7zFormat.txt - 7z Format description
-DOC/installer.txt - information about 7-Zip for installers
-DOC/lzma.txt - LZMA compression description
-DOC/lzma-sdk.txt - LZMA SDK description (this file)
-DOC/lzma-history.txt - history of LZMA SDK
-DOC/lzma-specification.txt - Specification of LZMA
-DOC/Methods.txt - Compression method IDs for .7z
-
-bin/installer/ - example script to create installer that uses SFX module,
-
-bin/7zdec.exe - simplified 7z archive decoder
-bin/7zr.exe - 7-Zip console program (reduced version)
-bin/x64/7zr.exe - 7-Zip console program (reduced version) (x64 version)
-bin/lzma.exe - file->file LZMA encoder/decoder for Windows
-bin/7zS2.sfx - small SFX module for installers (GUI version)
-bin/7zS2con.sfx - small SFX module for installers (Console version)
-bin/7zSD.sfx - SFX module for installers.
-
-
-7zDec.exe
----------
-7zDec.exe is simplified 7z archive decoder.
-It supports only LZMA, LZMA2, and PPMd methods.
-7zDec decodes whole solid block from 7z archive to RAM.
-The RAM consumption can be high.
-
-
-
-
-Source code structure
----------------------
-
-
-Asm/ - asm files (optimized code for CRC calculation and Intel-AES encryption)
-
-C/ - C files (compression / decompression and other)
- Util/
- 7z - 7z decoder program (decoding 7z files)
- Lzma - LZMA program (file->file LZMA encoder/decoder).
- LzmaLib - LZMA library (.DLL for Windows)
- SfxSetup - small SFX module for installers
-
-CPP/ -- CPP files
-
- Common - common files for C++ projects
- Windows - common files for Windows related code
-
- 7zip - files related to 7-Zip
-
- Archive - files related to archiving
-
- Common - common files for archive handling
- 7z - 7z C++ Encoder/Decoder
-
- Bundles - Modules that are bundles of other modules (files)
-
- Alone7z - 7zr.exe: Standalone 7-Zip console program (reduced version)
- Format7zExtractR - 7zxr.dll: Reduced version of 7z DLL: extracting from 7z/LZMA/BCJ/BCJ2.
- Format7zR - 7zr.dll: Reduced version of 7z DLL: extracting/compressing to 7z/LZMA/BCJ/BCJ2
- LzmaCon - lzma.exe: LZMA compression/decompression
- LzmaSpec - example code for LZMA Specification
- SFXCon - 7zCon.sfx: Console 7z SFX module
- SFXSetup - 7zS.sfx: 7z SFX module for installers
- SFXWin - 7z.sfx: GUI 7z SFX module
-
- Common - common files for 7-Zip
-
- Compress - files for compression/decompression
-
- Crypto - files for encryption / decompression
-
- UI - User Interface files
-
- Client7z - Test application for 7za.dll, 7zr.dll, 7zxr.dll
- Common - Common UI files
- Console - Code for console program (7z.exe)
- Explorer - Some code from 7-Zip Shell extension
- FileManager - Some GUI code from 7-Zip File Manager
- GUI - Some GUI code from 7-Zip
-
-
-CS/ - C# files
- 7zip
- Common - some common files for 7-Zip
- Compress - files related to compression/decompression
- LZ - files related to LZ (Lempel-Ziv) compression algorithm
- LZMA - LZMA compression/decompression
- 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)
-
-
-Note:
- Asm / C / C++ source code of LZMA SDK is part of 7-Zip's source code.
- 7-Zip's 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 modern 2 GHz cpu
- - 1-2 MB/s on 200 MHz simple RISC cpu: (ARM, MIPS, PowerPC)
- - 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) Mispredicted 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.
-
-
-2) LZMA e file.bin file.lzma -lc0 -lp2
-
-compresses file.bin to file.lzma with settings suitable
-for 32-bit periodical data (for example, ARM or MIPS code).
-
-3) LZMA d file.lzma file.bin
-
-decompresses file.lzma to file.bin.
-
-
-Compression ratio hints
------------------------
-
-Recommendations
----------------
-
-To increase the compression ratio for LZMA compressing it's desirable
-to have aligned data (if it's possible) and also it's desirable to locate
-data in such order, where code is grouped in one place and data is
-grouped in other place (it's better than such mixing: code, data, code,
-data, ...).
-
-
-Filters
--------
-You can increase the compression ratio for some data types, using
-special filters before compressing. For example, it's possible to
-increase the compression ratio on 5-10% for code for those CPU ISAs:
-x86, IA-64, ARM, ARM-Thumb, PowerPC, SPARC.
-
-You can find C source code of such filters in C/Bra*.* files
-
-You can check the compression ratio gain of these filters with such
-7-Zip commands (example for ARM code):
-No filter:
- 7z a a1.7z a.bin -m0=lzma
-
-With filter for little-endian ARM code:
- 7z a a2.7z a.bin -m0=arm -m1=lzma
-
-It works in such manner:
-Compressing = Filter_encoding + LZMA_encoding
-Decompressing = LZMA_decoding + Filter_decoding
-
-Compressing and decompressing speed of such filters is very high,
-so it will not increase decompressing time too much.
-Moreover, it reduces decompression time for LZMA_decoding,
-since compression ratio with filtering is higher.
-
-These filters convert CALL (calling procedure) instructions
-from relative offsets to absolute addresses, so such data becomes more
-compressible.
-
-For some ISAs (for example, for MIPS) it's impossible to get gain from such filter.
-
-
-
----
-
-http://www.7-zip.org
-http://www.7-zip.org/sdk.html
-http://www.7-zip.org/support.html
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