selective_sharpen - Sharpen edges in controlled fashion
Taken from an IRC log:
02:00 <@ tigert> selective sharpening 02:00 <@ tigert> UnNamed: 1) take the original photo, duplicate the layer 02:01 <@ tigert> UnNamed: 2) convert the copy to grayscale 02:01 <@ tigert> 3) run edge detect to the gray layer 02:01 <@ tigert> 4) blur it slightly 02:01 <@ tigert> 5) boost contrast (I can give you a specific curve or such) 02:01 < sjburges> tigert: on 3, what edge detect? 02:01 <@ tigert> sjburges: default works 02:01 <@ tigert> sjburges: size: 3 or 2 (default) 02:02 <@ tigert> sjburges: then make the boosted, gray edge-detection into a selection mask 02:02 <@ tigert> sjburges: then use unsharp mask to that selection (scratch the gray layer) 02:03 <@ tigert> sjburges: sjburges now, one could do two versions 02:03 <@ tigert> sjburges: so one version could just be "Select edges" 02:04 <@ tigert> sjburges: another could ask for unsharp mask parameters as well and sharpen 02:04 <@ tigert> sjburges: the idea for the script is to sharpen it without sharpening the noise on flat areas 02:04 < sjburges> tigert: could you fire me an email, and I can try to get to it tonight/tomorrow? It sounds simple enough. I need to head to a party for work shortly here 02:04 <@ tigert> sjburges: ok
[ PF_SPINNER, "sharpen_radius", "Radius of unsharp", 5.0, [0.1,120,0.1]], [ PF_SPINNER, "sharpen_amt", "Amount to unsharp", 1.0, [0.0,4.0,0.1]], [ PF_SPINNER, "threshold", "What delta to decide to sharp on", 20, [0,255,1]],
Seth Burgess <email@example.com>
Copyright 2004, Seth Burgess.
This filter may be distributed under the same terms as Gimp-Perl.