Ce filtre renforce, élargit les zones claires de l’image. Son action est l’inverse de celle du filtre Dilater

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.

Sur un fond uni, le filtre peut servir à supprimer le bruit, les parasites :

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