Mask dark or bright area

[Tornado]

Hi guys!

I would like to know if there's a function or method that help to filtering the dark or bright area
of course by using mask in Vapoursynth?

something like this : https://forum.videohelp.com/threads/388747-Avisynth-mask-to-target-plain-colors

Regards!

[_Al_]

Need adding grain to dark areas? Maybe kagefunc.py and its function adaptive_grain , it creates mask for it.

import kagefunc
video = kagefunc.adaptive_grain(video, strength=0.25)