Hi,
I am normalizing my functional images and resizing the voxel sizes when writing them out by calling
spm_write_sn(sliceTimed_realigned_images, spm_normalise_parameter_output_seg_sn.mat, flags)
where flags only specify output voxel size of [2 2 2] instead of the images' original 3x3x3 mm3, and I have tried the SPM8 default trilinear interpolation method and a couple of different b-spline degrees. Normalization seems to have worked fine (at least when visually inspecting brain boundaries against a template), but the resulting output files are unexpectedly big -- ~16MB, regardless of interpolation method, even though the raw NIFTI files and slice-timed/realigned images are only ~250kB. It seems like I might not be calling spm_write_sn correctly/am I missing a flag?
I also tried to check it against "Normalise: Write" via the batch editor, but I get the error:
Reference to non-existent field 'VG'....in spm_write_sn.m (v4201). function "get_xyzmat" at line 430
which superficially seems to be that the prm structure that gets passed has prm.sn.VG but not prm.VG...I didn't look further than that....
Any help and troubleshooting suggestions very much appreciated!
g
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