The Sharpen plug-in provides a sharpening filter to enhance the edges in a blurry image. The preview window shows the filter output using the current settings. The Sharpness control selects the amount of sharpening to apply, from 1 to 99 percent.
Higher values make the edges in the image increasing distinct.
The sharpen plug-in can restore some of the lost detail in a despeckled image. The feathers on the duck in the foreground were enhanced effectively by the filter. A contrast adjustment might bring the sharpened image even closer to the original.