[ENH] Add variance smoothing

[nicholst]

I usually tell people PALM does everything randomise/SnPM does and so much more. But I just realised PALM lacks one feature common to those two tools: Variance smoothing. For low DF it really can be an amazing power boost.

Smoothing of the variance image requires re-normalisation of the kernel according to the mask but otherwise is pretty straightforward, but I'm not sure how you'd do it on the mesh.

[andersonwinkler]

Hi Tom,
It can be done, yes. Let me think a bit the most efficient way... updates soon I hope...
Thanks!
Anderson

[andersonwinkler]

Hi Tom (@nicholst)

There is a problem with implementing it: it's easy enough for voxelwise data but for surfaces, it's less trivial and there's a number of algorithms available. It should be included, nonetheless...

Anderson

[nicholst]

Ahh... yes. Surface smoothing is not trivial.