I have been evaluating SPM 5/8's compatibility with the NIfTI standard and
am curious to know the extent that the different transformations qForm and
sForm embedded in the NIfTI header (either .hdr or .nii file) are
accommodated in SPM.
When I display a NIfTI file that includes a header with only the *sForm*
transformation, SPMs "Display" utility seems to display it correctly, and
the origin reported is as expected, say at [128 104 30]. However, when I
load the same image data with a header that includes only the *qForm*
transformation, I find the origin (and thus voxel space/world space) is
incorrect; e.g. the origin is now reported as [128 154 30]. It seems only
the second co-ordinate is wrong.
If I display my test data sets with MRIcroN or a NIfTI MATLAB toolbox, the
origin is reported identical as expected in all cases.
So, my question is, does SPM 5/8 only support one type of transformation,
either sForm or qForm. Which one should be used?
Is the above inconsistency a bug that needs to be fixed?
Thank-you for any comments to help me understand and resolve this problem!