Este filtro amplia e realça as áreas claras da camada ou seleção ativa.

For every image pixel, it brings the pixel Value (luminosity) into line with the upper value (the brightest) of the 8 neighboring pixels (3×3 matrix). So, a bright pixel is added around bright areas. An isolated pixel on a brighter background will be deleted. A larger bright area will dilate by one pixel in all directions.

On complex images, bright areas are widened and enhanced the same, and somewhat pixelated.

Já em imagens com fundo sólido, este filtro pode servir para remover ruído:

This filter is found in the main menu under Filters → Generic → Dilate.