[dxhdr]

One thing the article didn't mention is that a gaussian blur can be approximated with multiple passes of a box blur. Not sure how that would relate performance-wise to the discussed stack blur algorithm. The code would probably be a bit simpler, anyway.

[sudara]

I'm interested in this idea. I think I got confused at some point and mistakenly thought box blur was a 2D kernel and so it wouldn't perform great. vImage does contain a box blur but I haven't checked its performance (I did check the tent blur and it was so-so...) https://developer.apple.com/documentation/accelerate/blurrin...

[evrimoztamur]

From what I understand that’s what stack blur does, approximating the normal distribution.

[Jasper_]

Stack blur is a fast, discrete tent filter (weights are 1, 2, 3, 2, 1, normalize, it makes a triangle/tent shape). You can find tent filter blurs all over, including in Apple's own image processing library:

https://developer.apple.com/documentation/accelerate/vimage/...