I've seen an very interessting video (http://meetthegimp.org/episode-127-octave-sharpening/) about the so called "Octave Sharpening" I've never heard. So I started searching for some information about it and found also 2 other sharpening methods (http://www.varis.com/StepByStep/sharpen/Sharpen.html).
The PDF tutorial (second link) shows the function with Photoshop so I implemented the scripts for gimp and wondered how effectfull they are.
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