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UNSOLVED Quake 1/2 .PAK file support
Wishlist3 -
UNSOLVED Better archive type handling with drag & drop
Wishlist6 -
SOLVED Find file in archive.
Wishlist9 -
UNSOLVED Encrypt files inside archive that has already been created [.zipx]
Wishlist5 -
SOLVED Fast Extract large files directly to target directory
Wishlist4 -
SOLVED Serpent-256 Encryption for PAE/PAE2
Wishlist14 -
UNSOLVED Make portable version compatible with PortableApps
Wishlist1 -
UNSOLVED PBS Filenames
Wishlist3 -
UNSOLVED pCloud
Wishlist5 -
UNSOLVED ownCloud / Nextcloud
Wishlist1 -
UNSOLVED Setting to keep X number of backups
Wishlist11 -
SOLVED auto open first level in folder treeview when archive is opened
Wishlist8 -
SOLVED I think SVG files should be treated as text files.
Wishlist3 -
SOLVED Command Line Switch for View Mode
Wishlist12 -
UNSOLVED move back and forth via prev/next buttons in archive/folders
Wishlist8 -
SOLVED Different Hash Algorithns
Wishlist6 -
UNSOLVED Backups files ordering by NAME as default
Wishlist2 -
UNSOLVED czip support
Wishlist3 -
UNSOLVED using forward and back mouse buttons in interface
Wishlist4 -
UNSOLVED Backup and Comments
Wishlist1
7-Zip engine in PA 17 not as good as in 7-Zip 17
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I have been doing some test on 7-Zip compression inside PA, and noticed that 7-Zip 17.00 always get better compression ratios that PA with 7-Zip format. No matter if we choose LZMA or LZMA2.
I guess that the advantage on 7-Zip is because:
- Can use -myx=9 to improve ratio.
- Can use fastbytes=273 which is in 90% of cases best ratio
- Can use 128MB o 256MB dictionaries.
- Maybe because recent 7Z engine, is also better than the one in PA
Would be fine if those additional options can be setup inside PA, or either they are finetunned inside PA default values.
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@nikkho we dont really set manual options in 7z, we could though… how does it compare to PA format?
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I have compressed full PowerArchiver x64 portable in my SSD disk, so it is easy for you to reproduce.
- Uncompressed size: 176.473.679 bytes.
- 7-Zip 17.00 Ultra LZMA 128MB fb273 myx=9: 28.330.063 bytes.
- PowerArchiver 7z 17.00.69 LZMA Ultra: 29.060.624 bytes.
- 7-Zip 17.00 Ultra LZMA2 128MB fb273 myx=9: 28.323.572 bytes.
- PowerArchiver 17.00.69 7z LZMA2 Ultra: 29.062.095 bytes.
- PowerArchiver 17.00.69 7z Optimized Ultra: 41.579.382 bytes.
Take a look at the bad results with the Optimized profile, and also at the equivalent PA implementation, being slightly worse than the one in 7-Zip, meaning that the library used or its parameters, are subobtimal.
By the way, same with PA format, excellent results:
- PowerArchiver 17.00.69 pa Extreme Optimize Strong: 27.114.421 bytes.
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@spwolf myx was added in 7z 15.00 (https://sourceforge.net/p/sevenzip/discussion/45797/thread/fd1f6344/) and it improves results a bit at the cost of some additional analysis time.
As for fastbytes fb=273 is mostly the better.
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@nikkho cool, keep in mind for .pa we use 64M as default in extreme, so result with 128M dictionary would be even better due to codecs, not just settings.
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as to Optimized, there is something wrong with the settings, we will check it out. Thank you very much!
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Confirmed that the problem is fixed in 17.00.70, but still with some room for improvement:
- PowerArchiver 17.00.69 7z Optimized Ultra: 41.579.382 bytes.
- PowerArchiver 17.00.70 7z Optimized Ultra: 29.057.719 bytes.
