This filter enhances the apparent sharpness of the image. It’s heavily based on Marco Rossini’s excellent Wavelet sharpen GIMP plugin.
Normal Image:
https://push-3272.5centscdn.com/KB_IMG/balloon_5CC.jpg
Transformed Image:
https://push-3272.5centscdn.com/KB_IMG/balloon_5CC.jpg?im=filters:sharpen(2,1.0,true)
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