M2Team
v6 - Zstandard Compression Level selection is broken, resets Compression Method
NanaZip 6.0 Preview 1 (6.0.1461.0)
- Windows Explorer, right click any folder,
NanaZip Preview ... Add to Archive... - Archive Format = 7z, Compression Method = Zstandard
- change 'Compression Level'
- Compression Method is reset to
LZMA2
I could reproduce this. My hypothesis is due to the uncommenting of SetMethod() in #687.
Indeed, it's caused by SetMethod().
The particular reason why is that 7-zip mainline also doesn't attempt to preserve the compression method (try this with official mainline 7-zip and it will reproduce the same). This particular line is commented in 7-zip Zstandard.
@MouriNaruto do you think we should keep mainline behavior or try making it keep the compression method? Commenting back the method will cause the "Store" compression level to break.
The mainline has a commented line of SetMethod() that preserves the method, I wonder why it's commented.
Emmm, actually, 7-Zip mainline has many changes that I don't understand. I need some time to research.
Kenji Mouri
Seeing the same, but I'm also wondering if this is related to the number of zstd levels only being limited to 1-9 even though the standard actually goes up to 22? I was migrating from 7-Zip ZS which has the full range of compression levels:
