Filter limitation when frame changes strongly

[Selur]

Have you tried using an (inverted) edge mask and/or different denoisers (i.e. fft3dfilter and later apply cas)?
Other than that, you will probably have to try other masks, write your own code to combine masks or write your own masking code.
Maybe interesting:

• https://silentaperture.gitlab.io/mdbook-...sking.html
  
• https://lvsfunc.encode.moe/en/v0.4.2/sub.../mask.html
  

Cu Selur