[Insight-users] number of spatial samples

[Christos Panagiotou]

Dear Luis

in Mattes implementation of MI the number of spatial samples which the user
needs to set for the metric is around 20% of the pixels of the 
(biggest?) image to be registered
(i assume that in 3D it would be the number of voxels)

if we use a multi resolution method the number of spatial samples whould 
be adjusted for each level of the pyramid?
is this done automaticaly in the multiResolutionRegistrationMethod? do 
we have to implement it explicitly or do we just
set 20% of the finest (or lowest?) resolution level (1 1 1)