Sharpening filter
From AWF-Wiki
It is a high pass filter with the opposite effect as the Arithmetic mean filter increasing the contrast.
- In the search engine of the Processing Toolbox, type Simple filter and select Simple filter under Raster Filter of SAGA.
- Under the Parameters tab, select a single band as Grid.
- Select Circle from the drop-down list as Search Mode.
- Choose Sharpen as Filter
- Use 2 pixels as Radius.