ksubramz/nibabel-1 — comment on commit fa0db82497e5817294ba0d6e36f4099aa3846eb4
File: nibabel/freesurfer/mghformat.py line 247
By matthew-brett:

Are these always stored? I mean, is it possible to have empty values here, such that you don't really know the affine of the image? If so, that means it might be necessary to guess an affine - the role of the 'bare' affine in the Analyze header objects.