Using spm99, I have been deriving spatial normalization parameters
using a high-resolution T1 structural and then applying these
parameters to statistical files (derived from non-spm software)
using the "Write Normalised Only" option. I find that in some
cases, spm deletes all if the data that fell below the origin (-Z)
of the original, un-normalized files when writing the normalized files.
I have yet to find the one variable that predicts this behavior.
After some investigation, I've found that it always happens when I
mix multiple files of different precision (8bit, 16bit and/or floating
point) in one Write Normalised session, but I also find it
occasionally with single files put by themselves in a separate directory.
It happens with both sync and nearest neighbor interpolation. It happens
with both integer and non-integer target pixel sizes. I'm not sure
what else to try.
Has anyone else seen this? Any suggestions would be greatly appreciated.
Thanks in advance,
Vince
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|