Results 1 to 11 of 11

Thread: PAQ8K

  1. #1
    Member
    Join Date
    Dec 2006
    Posts
    611
    Thanks
    0
    Thanked 1 Time in 1 Post
    Bill Pettis released new version of PAQ!
    http://ilovemyking.googlepages.com/paq8k.zip

    EDIT: On brief test it seems, that majority of files will give better results

  2. #2
    Moderator

    Join Date
    May 2008
    Location
    Tristan da Cunha
    Posts
    2,034
    Thanks
    0
    Thanked 4 Times in 4 Posts
    Thanks BF!

    Is this version any slower than PAQ8jd?

  3. #3
    Member
    Join Date
    Dec 2006
    Posts
    611
    Thanks
    0
    Thanked 1 Time in 1 Post
    I tried only PNG up to now - PAQ8K is 3-4x slower on the one from my testset.

  4. #4
    Moderator

    Join Date
    May 2008
    Location
    Tristan da Cunha
    Posts
    2,034
    Thanks
    0
    Thanked 4 Times in 4 Posts
    Quote Originally Posted by Black_Fox
    PAQ8K is 3-4x slower on the one from my testset.
    WOW! That is much slower than I had expected.

  5. #5
    Member
    Join Date
    Jun 2008
    Location
    G
    Posts
    372
    Thanks
    26
    Thanked 22 Times in 15 Posts
    yeah iam also testing and waiting........

    Why is so slow?
    What of the things did you implement, thats so slow?
    Did you compile with asm?
    What is a Chartmodel?

  6. #6
    Member
    Join Date
    Jun 2008
    Location
    G
    Posts
    372
    Thanks
    26
    Thanked 22 Times in 15 Posts
    here my first test:

    Cokumente und EinstellungenThomasDesktop>paq8jdsse.exe -6 win.wav
    Creating archive win.wav.paq8jd with 1 file(s)...
    win.wav 1709576 -> 1404345
    1709576 -> 1404375
    Time 300.83 sec, used 531535259 bytes of memory

    Cokumente und EinstellungenThomasDesktop>paq8k.exe -6 win win.wav
    Creating archive win.paq8k with 1 file(s)...
    win.wav 1709576 -> 1409989
    1709576 -> 1410018
    Time 852.45 sec, used 419251344 bytes of memory

    Cokumente und EinstellungenThomasDesktop>

    I think its not good that you reduce memory requirements because of benchmarking with older versions.

  7. #7
    Member
    Join Date
    Jun 2008
    Location
    G
    Posts
    372
    Thanks
    26
    Thanked 22 Times in 15 Posts
    here my second testset

    Compressed Tar was the old Transport Tycoon + OpenTTD with only a few save games.

    Cokumente und EinstellungenThomasDesktop>paq8jdsse.exe -6 TT.tar
    Creating archive TT.tar.paq8jd with 1 file(s)...
    TT.tar 37218304 -> 22987894
    37218304 -> 22987924
    Time 6487.64 sec, used 539930268 bytes of memory

    Cokumente und EinstellungenThomasDesktop>paq8k.exe -6 8k TT.tar
    Creating archive 8k.paq8k with 1 file(s)...
    TT.tar 37218304 -> 22963807
    37218304 -> 22963836
    Time 16798.89 sec, used 427646354 bytes of memory

  8. #8
    Moderator

    Join Date
    May 2008
    Location
    Tristan da Cunha
    Posts
    2,034
    Thanks
    0
    Thanked 4 Times in 4 Posts
    Thanks thometal!

    I had planned to use a slightly modified version of PAQ8k with PeaZip but its far too slow to replace PAQ8jd.

  9. #9
    Expert
    Matt Mahoney's Avatar
    Join Date
    May 2008
    Location
    Melbourne, Florida, USA
    Posts
    3,255
    Thanks
    306
    Thanked 779 Times in 486 Posts
    I tested paq8k on the Calgary corpus. It compresses about 0.1% smaller than paq8jd but is 3 times slower. It is the top result now.
    http://cs.fit.edu/~mmahoney/compression/

    On enwik8 it compresses worse than paq8jd. It took about 13 hours. I did not verify decompression and I have no plans to test on enwik9.
    paq8jd -7 18,158,159
    -8 17,943,042
    paq8k -8 18,239,915
    http://cs.fit.edu/~mmahoney/compression/text.html# 1334

    I looked at the code and I still can't tell what a chart model is. Putting the indirect model in a loop doesn't make sense to me either.

    Here are the Calgary tests for paq8jd and paq8k. I had to put all the filenames on the command line in paq8k because wildcards and directory traverse are broken. (Probably both could be fixed by compiling with g++ -DWINDOWS but I used the .exe from the website).

    C:
    es>timer compresspaq8jdpaq8jd -7 calgary
    Timer 3.01 Copyright (c) 2002-2003 Igor Pavlov 2003-07-10
    Creating archive calgary.paq8jd with 14 file(s)...
    calgary/BIB 111261 -> 20888
    calgary/BOOK1 768771 -> 192375
    calgary/BOOK2 610856 -> 117535
    calgary/GEO 102400 -> 43983
    calgary/NEWS 377109 -> 83911
    calgary/OBJ1 21504 -> 7366
    calgary/OBJ2 246814 -> 44522
    calgary/PAPER1 53161 -> 10510
    calgary/PAPER2 82199 -> 16572
    calgary/PIC 513216 -> 23025
    calgary/PROGC 39611 -> 8380
    calgary/PROGL 71646 -> 9779
    calgary/PROGP 49379 -> 6904
    calgary/TRANS 93695 -> 10122
    3141622 -> 596179
    Time 527.42 sec, used 1030659022 bytes of memory

    Kernel Time = 1.609 = 00:00:01.609 = 0%
    User Time = 489.968 = 00:08:09.968 = 92%
    Process Time = 491.578 = 00:08:11.578 = 93%
    Global Time = 527.531 = 00:08:47.531 = 100%


    C:
    escalgary>timer
    escompresspaq8kpaq8k -7 ..cal bib book1 book2 geo news obj1 obj2 paper1 paper2 pic progc progl progp trans

    Timer 3.01 Copyright (c) 2002-2003 Igor Pavlov 2003-07-10
    Creating archive ..cal.paq8k with 14 file(s)...
    bib 111261 -> 20700
    book1 768771 -> 193523
    book2 610856 -> 117420
    geo 102400 -> 43976
    news 377109 -> 83522
    obj1 21504 -> 7185
    obj2 246814 -> 43440
    paper1 53161 -> 10526
    paper2 82199 -> 16660
    pic 513216 -> 23738
    progc 39611 -> 8294
    progl 71646 -> 9651
    progp 49379 -> 6771
    trans 93695 -> 9937
    3141622 -> 595537
    Time 1540.77 sec, used 767380400 bytes of memory

    Kernel Time = 1.328 = 00:00:01.328 = 0%
    User Time = 1434.500 = 00:23:54.500 = 93%
    Process Time = 1435.828 = 00:23:55.828 = 93%
    Global Time = 1540.828 = 00:25:40.828 = 100%

  10. #10
    Moderator

    Join Date
    May 2008
    Location
    Tristan da Cunha
    Posts
    2,034
    Thanks
    0
    Thanked 4 Times in 4 Posts
    Thanks for the update Matt!

    Quote Originally Posted by Matt Mahoney
    I tested paq8k on the Calgary corpus. It compresses about 0.1% smaller than paq8jd but is 3 times slower. It is the top result now.
    Im sticking with PAQ8jd for the time being!

    Quote Originally Posted by Matt Mahoney
    On enwik8 it compresses worse than paq8jd. It took about 13 hours. I did not verify decompression and I have no plans to test on enwik9.
    I dont blame you!

  11. #11
    Member
    Join Date
    Dec 2006
    Posts
    611
    Thanks
    0
    Thanked 1 Time in 1 Post
    Quote Originally Posted by thometal
    What of the things did you implement, thats so slow?
    Did you compile with asm?
    What is a Chartmodel?
    I wonder why is Bill so humble with any details... there isnt a word about it even on his site
    But it really is top PAQ version now

Similar Threads

  1. PAQ8K
    By LovePimple in forum Data Compression
    Replies: 63
    Last Post: 19th March 2010, 05:52

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •