A simple GEGL filter to reduce noise.
You can find this filter through Filters → Enhance → Noise Reduction….
Figura 17.32. Noise Reduction filter options
These options are common to GEGL-based filters. Please refer to Seção 2, “Common Features”.
Increasing Strength lessens noise, and increases blur: find compromise using the on-canvas preview.
Original
Filter applied. Strength = 5