Hi, anyone coded/got an algorithm for sharpening an image using the Unsharp Mask method?
Thanks
Jim
Thanks
Jim
Unsharp Mask
Miscellaneous Forums/General Discussion/Unsharp Mask If it helps, there's "a technique similar to unsharp masking, but which uses a median filter instead of a gaussian blur" available here: Sharpen (several incarnations, actually).
I believe Sswift may know a fair bit about this, recalled him doing a little work regarding filters for one of his programs long ago.
My source is in that code archive entry that Wendell linked to. It's down at the bottom. The technique here is not unsharp though, it is median sharpening. The two are very similar and I think I included the ability in my source to switch between them. The only difference is you median filter the image instead of blurring it at one point in the process.
Median sharpening doesn't produce halos around objects, but unsharp is more popular for various reasons. I put median sharpening in my texture generator, cause it enhances noise and noise makes textures look sharper and they'll get blurred some from the filtering in the game. And it doesn't have the halos like I mentioned. On general photos, unsharp seems to be better, and median is again good for sharpening CG a bit.
Median sharpening doesn't produce halos around objects, but unsharp is more popular for various reasons. I put median sharpening in my texture generator, cause it enhances noise and noise makes textures look sharper and they'll get blurred some from the filtering in the game. And it doesn't have the halos like I mentioned. On general photos, unsharp seems to be better, and median is again good for sharpening CG a bit.