TNPGEnc Noise Reduction

[LavaJockey]

I like the Noise Reduction filter in TMPGEnc. However, it slows my encoding speed by a factor of 3. What exactly is it doing? Can I achieve the same quality noise reduction with VirtualDub filters? If so, what combination of VirtualDub filters, and in what order?

[kinneera]

The noise reduction filter appears to be performing filtering equivalent to that provided by a spatial and temporal smoother combination in VirtualDub (with much greater emphasis on the spatial part).

[LavaJockey]

Are temporal filters possible in VirtualDub? I thought there was a limitation in the way VirtualDub was implmented: filters calculate each output frame using only the
single corresponding input frame
(no other frames).

[kinneera]

You may be correct, I generally think in terms of Avisynth, which definitely does support temporal filtering.