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Distributed WinRAR Compression Ratios

Discussion in 'Software' started by Entropy, 11 Mar 2009.

  1. Entropy

    Entropy le mayo

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    I'm trying to compress a 1.89GB .iso file so that it will fit on my "2GB" flash drive (which actually has a capacity of 1.86GB (2 000 060 416 bytes), but every time it ends up with a compression ratio of 99% which, unfortunately is 1% too high for it to be able to fit...

    Does anyone know why it's compressing at such a bad ratio?
     
  2. kenco_uk

    kenco_uk I unsuccessfully then tried again

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  3. Delphium

    Delphium Eyefinity enabled

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    It will also depends on the content being compressed, files such as .jpg, .mp3, .ogg, .avi, .vob and some other media formats are already compressed, so packing them inside a zip/rar/7zip wont make much if any difference :/

    If you have a 2nd stick handy then you could maybe span the zip/rar archive across the 2 sticks, seeing as your likely to extract it again on destination.

    EDIT: w00t 1000th post x]
     
    Last edited: 11 Mar 2009
  4. mm vr

    mm vr The cheesecake is a lie

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    Yep, what Delphium said... You can't compress something that has been already compressed.

    So if it's a game ISO, no way. They usually contain CAB files which are already packed.

    But you might get lucky if you try another compression program, such as 7-Zip or KGB Archiver. And remember to choose the best compression ratio, whatever program you use.

    And if nothing helps, again as Delphium said, create 1.8GB parts (at least RAR and 7z support them) and you'll end up with one 1.8GB file and one ~60MB file which you need both for uncompressing it. You could transport them on two USB disks, or if you only got one, you can transport them one at a time.
     
  5. azrael-

    azrael- I'm special...

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    Actually, choosing the best compression algorithm can sometimes be counterproductive. WinRAR had at one point a special "multimedia" compression setting, but as far as I can tell it's no longer there.

    7zip might actually yield a slightly higher compression ratio to WinRAR, so if you've got the time to spare give it a go. WinRAR can decompress 7zip files if you haven't 7zip installed on the target computer.
     
  6. Entropy

    Entropy le mayo

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    It's a Delphi 2009 ISO, and unfortunately 7zip got me to the exact same stage as WinRAR.

    Nevermind, I'll just go get a blank DVD...

    Thanks for the help though :)
     
  7. Krikkit

    Krikkit All glory to the hypnotoad! Super Moderator

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    I suppose seenas you're going to take it on a pendrive, a doovde won't make much difference...
     
  8. kenco_uk

    kenco_uk I unsuccessfully then tried again

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    Did you compress to a 7z file or a rar file?
     
  9. jhanlon303

    jhanlon303 The Keeper of History

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    Spend $20 and get a bigger drive. They are cheap.

    I have a new drive that has USB on one end and eSATA on the other - 32Gb. Not cheap but bootable.

    john
     

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