[MEncoder-users] Noise reduction and interlacing: (hq)denoise3d vs. nr

[Nico Sabbi]

Ivo wrote:

>IMHO tfields/tinterlace is prefered if you run a temporal denoiser. If you 
>only (de)interleave as Nico suggested, the denoiser works with different 
>data and will perform worse.
>
>For example: (F=frame, f=field)
>
>Input F1(f1,f2) F2(f3,f4) F3(f5,f6) etc...
>
>Fictional denoiser uses current frame, and the next two frames.
>
>If you use il=d and il=i:
>    F1 is denoised by using f1<-->f3<-->f5 and f2<-->f4<-->f6
>If you use tfields and tinterlace:
>    F1 is denoised by using f1<-->f2<-->f3 and f2<-->f3<-->f4
>
>  
>
that means that frame F1 is denoised using:
- as top field a rework of  topf1<-->bottomf2<-->topf3
- as bottom field a rework of bottomf2<-->topf3<-->bottomf4,
right?
I don't know the theory and I don't understand why a denoiser should
perform better when dealing with fields generated by an interpolation of
the actual and the other field(s)
Can you explain, please?