Version: unknown (using KDE 3.5.2 Level "a" , SUSE 10.0 UNSUPPORTED) Compiler: Target: i586-suse-linux OS: Linux (i686) release 2.6.13-15.8-default The radius of the "unsharp mask" digikam-imageplugin filter (svn version, as of 15.05.2006) is limited to a radius of 10 which is way too low. The unsharp mask filter has too uses: to sharpen a image (radius 0.1 to ~5 pixel) and to apply a local contrast enhancement (radius ~5% of image width). The second use case is not possible with digikam's unsharp mask plugin. Example: Take a 5MPixel image done at a day with bad weather and apply an unsharp mask with radius: 90 pixel, strength: 0.3, threshold:0. (you can do this with gimp, too) Would be nice, if someone could remove this artificial constraint of digikam's unsharp mask.
All old settings limits have been restored from 0.8.x serie. Note : this plugin use a new algorithm based on ImageMagick implementation to support 16 bits image, not gimp algorithm !
closed
Hi, > ------- Additional Comments From caulier.gilles free fr > All old settings limits have been restored from 0.8.x serie. Thanks for the quick response! > Note > : this plugin use a new algorithm based on ImageMagick implementation to > support 16 bits image, not gimp algorithm ! What does this mean? It seems to be impossible now to use a radius below 1 pixel. Btw.: Is it intentional that most plugin dialogs do not state which units are used? Sharpness: 0 - 100: Percent? Some other unit? Gaussian blur: 0 - 100: Radius in Pixel? Noise reduction: ?? (How do I reduce the strength of the default noise reduction to e.g. 50%? No idea, maybe I should look into the handbook...) Unsharp mask: Radius: 0 - 100: Pixel? Amount: 0 - 1: Strength normalized to 1? Threshold: 0 - 1: Pixel color normalized to 1? But the histogram shows pixel colors in the range from 0 - 255 (for 8 bit images). Should be the same, should'nt it? Anti-Vignetting: Density: 1 - 20: Percent? Not really, seems to be something other Distortion effect: Iteration: 0 - 100: ?? Seems to have no effect... (Bug?) [...] Regards, Matthias
E.g. as of http://redskiesatnight.com/Articles/IMsharpen/ the radius as defined in gimp, Photoshop or ImageMagick are the same, so digikam should be able to use a smaller radius than 1 and other non integral values.
This bug is marked as closed, should this be re-opened or would it be better to set up a new one?
> or would it be better to set up a new one? Setup new one with expanded version: also minimal radius of 1.0 pixel is too big. In many texts about USM radius smaller than 1 pixel is recommended for some tasks. m.
Roman, could you please file a new bug for you wish? (Otherwise it gets lost because this bug is closed.) Many thanks, Arnd
I re-open this bug, as it has not been fully addressed, and if I am not mistaken, no separate wish has been filed.
Radius settings rule have changed with 4.x release. For me current implementation from git/master work fine. Gilles Caulier