The option called cumulative function calculates the mean values over a pixel and a specified buffer areas around it. The dimension defines the number of pixels in each direction over which the mean values are calculated. The cumulative function has no dependencies.
Multiple application of the cumulative function leads to a relative weighting of the sourounding pixels according to their proximity.
Open the function settings dialog by double-clicking at the Option icon at the file tree.
Within the cumulative function settings dialog the dimensions can be set and equal the number of pixels in each direction over which the mean values are calculated. NODATA values are dismissed from the calculation.