First of all, happy new year 2021! All the best for all of you in this new year.
Recently, I read and tried to use grdfft to filter a geotiff with no success so far. Before keep trying, I would like to ask if it is possible what I am after. I enclosed a figure here to show the steps I want to do. Based on this figure, is grdfft the right tool to do the filtering (original -> filtered)? I understand it is.
I would appreciate your support,
All the best,