Imagine saving a .png image of a solid-colored circle that is on top of a transparent background. However, the circle is filled with that solid color in such a way that towards its outer contours (circumference), there is a feathering effect that blends into the transparent background, therefore, a dispersion of the solid color into different gradients of it.
How to properly fill this circle to its outer most extremity with the solid color and the solid color alone, covering up the gradient feathering? The fill bucket tool isn't cutting it for complex-edged shapes like a circle since pixelation occurs. Gimp or Photoshop answers would do.