Looking into info about GIMP for Krita development

  1. Where can I find the code used for surface blur in GIMP source code?

  2. Is there any info besides from the source that tells me how all of the 5 options of GIMP High Pass mode works?

I plan to implement those two into Krita. Part of 2 has been almost done with nondestructive support. I’ll be able to do #1 as a filter mask/filter layer.

Bonus options, a way to replicate PS vibrance.

Found the info I need without using GIMP here - Gimp-Scripts/high-pass.scm at master · andymeneely/Gimp-Scripts · GitHub

Also, I think I could do surface blur via editing unsharp mask filter. Looks like I may be able to address Krita filter limits issue.