May 26, 2018
GIMP plugin to “refocus” images through FIR Wiener filtering
[ edited excerpt from developer’s www site ]
During image processing operations such as scanning and scaling, images tend to get blurry.
The blurred impression of these images is due to the fact that image pixels are averaged with their neighbors. Blurred images don’t have sharp boundaries and look as though they have been taken with an unfocussed camera.
Refocus is a GIMP plug-in to “refocus” the image, using a technique called FIR Wiener filtering. The traditional technique for sharpening images is to use unsharp masking. Refocus generally produces better results than unsharp masking.
The plugin can be found under “Filters > Enhance > Refocus”