A filter for post-processing digital images and videos, having an edge mapper,
a pixel sorter, and an adaptive filter that simultaneously performs de-ringing
and edge sharpening. The combined filter is computationally simpler than known
methods and can achieve removal of ringing artifacts and sharpening of true edges
at the same time. The present invention also includes a preferred method of simultaneously
de-ringing and edge sharpening digital images and videos.