afni.nimh.nih.gov

Hi,

If you want to include voxels that touch faces, rmm=1mm for a data set with 1mm resolution. If you want to include voxels that share an edge, you need to extend rmm (the center to center distance of voxel centers) to the square root of 2 (1.41...). If you want to include voxels that share a corner, then you need to extend rmm to be square root of 3 (1.7...). It is just a geometry problem, ala' Pythagoras.

-Jim