Why are you using havsfunc?
better use KNLMeansCL directly.
No need to add another dependency.
https://github.com/Selur/VapoursynthScri...c.py#L5948
is only used to filter 'Y' and 'UV' separately to speed it up, but in your case there is no need to filter 'UV' at all.
Cu Selur
Ps.: uploaded a test version which does include KNLMeans, but not havsfunc.
clip = havsfunc.KNLMeansCL(clip=clip, d=1, a=2, s=4, h=dstr, device_type="gpu", device_id=0)
clip = core.knlm.KNLMeansCL(clip=clip, d=1, a=2, s=4, h=dstr, channels='Y', device_type="gpu", device_id=0)
https://github.com/Selur/VapoursynthScri...c.py#L5948
is only used to filter 'Y' and 'UV' separately to speed it up, but in your case there is no need to filter 'UV' at all.
Cu Selur
Ps.: uploaded a test version which does include KNLMeans, but not havsfunc.