NIfTI

Fields: https://github.com/nipy/nibabel/blob/master/doc/source/external/nifti1.h

qform/sform:

• http://nifti.nimh.nih.gov/nifti-1/documentation/nifti1fields/nifti1fields_pages/qsform.html

• http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/Orientation%20Explained