This is a neat article with some good experimentation, but... This is essentially someone seeing the precursor to the bilateral filter for the first time withou

This is a neat article with some good experimentation, but... This is essentially someone seeing the precursor to the bilateral filter for the first time without ever having heard of a bilateral filter before. A bilateral filter weights surrounding pixels by how close in value they are. This ends up creating a smoothing effect from soft clustering. Take a look at the 'rolling guidance filter' for an effect when used iteratively.