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Thread: LZW v0.2 is here!

  1. #1
    The Founder encode's Avatar
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    OK, a bundle package at this time, which contains:
    lzw.exe - Compressor
    unlzw.exe - Decompressor
    unlzw.cpp - Decompressor source (C++, public domain)
    unlzw.zip - Zipped decompressor source

    The decoder source size is - 1,195 bytes
    The zipped decoder source size is just - 671 bytes!

    I think this one is a smallest decoder ever!

    Note that this release is mainly intended for Large Text Benchmark.

    Link:
    lzw02.zip (76 KB)


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    Thanks encode!
    Code:
    enwik8: 
    lzw v0.2 by encode 
    warning: running in DEBUG mode 
      95.32 MB -> 40.00 MB (41.96%) 
    done 
    Process Time =   385.437 = 00:06:25.437 =  96% 
    Global Time  =   400.875 = 00:06:40.875 = 100% 
     
    unlzw v0.2 by encode 
    done 
    Process Time =     3.390 = 00:00:03.390 =  69% 
    Global Time  =     4.891 = 00:00:04.891 = 100%

  3. #3
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    Thanks Ilia!

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    If I finally add a super fast compression, new LZW might be a powerhouse...
    Note that seems to be the LZW v0.2 is the only available program that uses LZMW...


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    Quote Originally Posted by encode
    add a super fast compression
    Fantastic!

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  7. #7
    The Founder encode's Avatar
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    Thank you Matt!

    By the way, does anyone have ideas about how to create the compression process faster?

    Currently I use linked lists:

    lnk[current_2bytes] -> the last note seen

    Each node has "prv" link to previous node of the same 2 bytes beginning.

    Such scheme works very slow...

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