Posted September 06, 2012
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Elenarie
@tweetelenarie
Registered: Sep 2008
From Sweden
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Nirth
GFN / VR / Switch!
Registered: Oct 2010
From Other
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Smannesman
4-bit classic
Registered: Oct 2010
From Netherlands
Posted September 06, 2012
Gizmo's Freeware is a pretty good site for some applications.
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Warmdrink
PGP 30E698EA
Registered: Dec 2008
From Canada
Posted September 06, 2012
Winrar just uses the same libraries as 7zip, so 7zip's performance will be 1:1 with Winrar.
The same goes for just about every compression tool. They're all just frontends to the various compression libraries. It's just that some, like Winrar, abuse the LGPL to try and make money out of you.
The same goes for just about every compression tool. They're all just frontends to the various compression libraries. It's just that some, like Winrar, abuse the LGPL to try and make money out of you.
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Elenarie
@tweetelenarie
Registered: Sep 2008
From Sweden
Posted September 06, 2012
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The same goes for just about every compression tool. They're all just frontends to the various compression libraries. It's just that some, like Winrar, abuse the LGPL to try and make money out of you.
Further, 7Zip cannot create RAR, and WinRAR cannot create 7Z.
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Maighstir
THIS KNIGHT MISLIKES THESE HEIGHTS
Registered: Nov 2008
From Sweden
Posted September 06, 2012
For the formats that are common between them, I assume, zip for example (which is the only format both mentioned applications can create, though they can both open a host of others).
Post edited September 06, 2012 by Miaghstir
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timppu
Favorite race: Formula__One
Registered: Jun 2011
From Finland
Posted September 06, 2012
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Is this some known problem with 7-zip? Naturally reliability is the #1 priority with a compression program, I definitely do not want to create archives with a broken algorithm even if it creates corrupted archives "only" e.g. 1% of the time.
To me WinRAR has always seemed quite dependable, and I'm hoping the same from e.g. 7-zip.
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Elenarie
@tweetelenarie
Registered: Sep 2008
From Sweden
Posted September 06, 2012
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Is this some known problem with 7-zip? Naturally reliability is the #1 priority with a compression program, I definitely do not want to create archives with a broken algorithm even if it creates corrupted archives "only" e.g. 1% of the time.
To me WinRAR has always seemed quite dependable, and I'm hoping the same from e.g. 7-zip.
Was unable to extract a single file out of them, had to extract the whole archive.
On the other hand, had similar problems with WinRAR, saying that the archive is corrupted, but the extraction worked with 7zip... go figure.
Btw, the archives I had trouble with were either zip ones or 7zip ones, don't remember the exact format.
Post edited September 06, 2012 by Elenarie
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timppu
Favorite race: Formula__One
Registered: Jun 2011
From Finland
Posted September 06, 2012
I definitely remember sometimes having problems extracting rar files. I think the reason was simply that my version of WinRAR was not up to date, and the rar archive was made with a newer version.
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Dzsono
Scientician
Registered: Apr 2011
From Hungary
Posted September 06, 2012
Try PeaZip. It does everything, seriously, everything, and it's open source. Lot's of people have recommended 7-zip which is also fantastic, but PeaZip can do the same and more!
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Nirth
GFN / VR / Switch!
Registered: Oct 2010
From Other
Posted September 06, 2012
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Is this some known problem with 7-zip? Naturally reliability is the #1 priority with a compression program, I definitely do not want to create archives with a broken algorithm even if it creates corrupted archives "only" e.g. 1% of the time.
To me WinRAR has always seemed quite dependable, and I'm hoping the same from e.g. 7-zip.
I wouldn't hesitate to recommend 7-zip, the only reason I actually came in this thread was because Elenarie's statement about using Ultra compression and I've never seen a good ratio when running something like that.
If you're worried about corruption you could do some testing. For example, take a couple of different file types and copy them to different sizes like a few kbs, megs and then gigs. Then move these files to other computers or the device/hard drive you plan on keeping them then move back and extract them. If no issues arise during this process I think you're good to go.
That looks interesting. Does it support 7-zip because 7-zip is open source as well so their format shouldn't be closed or something like that?
Post edited September 06, 2012 by Nirth_90
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Dzsono
Scientician
Registered: Apr 2011
From Hungary
Posted September 06, 2012
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Barefoot_Monkey
invertEd
Registered: Sep 2008
From South Africa
Posted September 06, 2012
That's not actually true. I assume that you're talking about their .zip and .gz support - well, most compression tools use zlib for those but 7-Zip has its own implementation. You'll most likely find that zip encoding with 7-Zip is slightly slower that with zlib, but with better compression.
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JMich
A Horrible Human Person. If you need me, chat.
Registered: Apr 2011
From Greece
Posted September 07, 2012
7-zip by default creates solid archives (can't recall exactly how it calls them) which basically treats the files as one continuous stream of data instead of seperate streams. It will usually offer better compression rate, but it does mean you have to decompress the stream until you reach that part of it you want. WinRAR also has the same setting, though it isn't on by default.
Also, sometimes if an archive is created with a newer version, older versions won't be able to extract it. Same deal with WinRar, at least until the 7z library of it gets updated, which is slower than just grabbing a new version of 7-zip.
Also, sometimes if an archive is created with a newer version, older versions won't be able to extract it. Same deal with WinRar, at least until the 7z library of it gets updated, which is slower than just grabbing a new version of 7-zip.
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Elenarie
@tweetelenarie
Registered: Sep 2008
From Sweden
Posted September 07, 2012
Maybe in earlier versions, but in the newer ones, the archives are definitely not solid by default... at least, not in 9.20.
Besides, there's little point in creating solid archives, the gain in lower file size is almost unnoticeable, though I guess it is fine for archives with a single file only.
Besides, there's little point in creating solid archives, the gain in lower file size is almost unnoticeable, though I guess it is fine for archives with a single file only.