Bug 151409

Summary: Support unsharp masking using fractional radius
Product: [Applications] krita Reporter: Dik Takken <kde>
Component: GeneralAssignee: Krita Bugs <krita-bugs-null>
Status: RESOLVED FIXED    
Severity: wishlist CC: halla
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Gentoo Packages   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Dik Takken 2007-10-26 22:37:13 UTC 
Version:           1.6.3 (using KDE KDE 3.5.7)
Installed from:    Gentoo Packages
OS:                Linux

Unsharp masking using a fractional radius (1.5 or 1.8) is used quite often for high quality printing. It is also used to correct slight blurring caused by many scalers. Unfortunately, Krita does not support this yet.
Comment 1 Halla Rempt 2007-12-06 13:46:48 UTC 
Wouldn't it also be a good idea to conform to the common terms and use radius, amount and threshold, instead of half-size, amount and threshold? Also, the ranges we allow differ from, frex, Photoshop, where:

radius: 0.1-250f
amount: 1-500%
threshold: 0-255

and in Krita everything is 0-99
Comment 2 Cyrille Berger 2007-12-06 15:13:54 UTC 
Rather than radius, it should use the sigma, and the range is 0-1000. Amount is currently expressed as float instead of percent and is in the range 0.0 - 5.0 (the gimp allows up to 10.0). And finally threshold is in the range 0-255. At least in 1.6, if that's not the case in trunk, then it indeeds need to be fixed, but that might mean we have lost all our range for filters configuration during the port to Qt4/KDE4.