Photopea and Gimp do compute the same thing (Surface Blur by definition). However, in Photoshop, the results at the radius >= 50px are slightly different. I hav

Photopea and Gimp do compute the same thing (Surface Blur by definition). However, in Photoshop, the results at the radius >= 50px are slightly different. I have a suspicion, that Photoshop uses an approximation algorithm. N*10 algorithm has an overhead, it needs a little more time (and memory) per pixel, but it does not depend on the radius. It is an exact algorithm (no approximation).