Xceed Zip for COM/ActiveX on x86/x64 Documentation
Xceed Compression control reference / Xceed Compression control properties / CompressionMethod property_compression
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    CompressionMethod property_compression
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    Description

    The CompressionMethod property allows you to specify which compression algorithm should be used by the Compress method when compressing data.

    Data type

    xcdCompressionMethod

    Possible values

    Value Meaning
    xcmStored   No compression or decompression should be applied at all.
    xcmDeflated   Use the Deflate compression method. This algorithm provides fast compression and decompression speeds and achieves pretty good compression.
    xcmDeflated64  Use the Deflate64 compression method. This method takes longer to compress data than Deflate, however it provides better compression.
    xcmLZMA

    Use the LZMA compression method.

    The Lempel-Ziv-Markov chain-Algorithm (LZMA) uses an improved and optimized version of the Lempel-Ziv (LZ77) compression algorithm, backed by a Markov chain range encoder. It uses a variable dictionary size. Used in zip files created with WinZip 12.0 and up.

    LZMA typically provides much better compression than the Deflate and Deflate64 algorithms at the expense of speed and memory usage when compressing. It also typically provides compression ratios a little better than BZip2/BWT and PPMd while being a little faster.

    Compression usually requires (<dictionary size> * 11.5 + 6 MB).

    Decompression is usually fast and requires <dictionary size> + 16K.

    xcmBurrowsWheeler   Use the BWT compression method. This algorithm often provides superior compression on many popular file types such as database, picture, text and executable files. It takes longer to compress or uncompress data with this algorithm vs. the standard Deflate algorithm.

    Default value

    xcmDeflated

    Declaration (DLL API)  

    UINT XcGetCompressionMethod( HXCEEDCMP hComp );

    void XcSetCompressionMethod( HXCEEDCMP hComp, UINT uValue );

    Applicable methods

    Compress