Hi experts, I'm using the latest nifticlib (http://niftilib.sourceforge.net/) to load NIFTI files with my C application. However, I noticed differences in the q-form matrix and derived orientation compared with those from fslhd: with fslhd I get ... ... qform_name Scanner Anat qform_code 1 qto_xyz:1 -0.873408 0.051653 0.014708 119.279884 qto_xyz:2 0.049023 0.860391 -0.207760 -111.342300 qto_xyz:3 0.019488 0.150616 1.181787 -21.342064 qto_xyz:4 0.000000 0.000000 0.000000 1.000000 qform_xorient Right-to-Left qform_yorient Posterior-to-Anterior qform_zorient Inferior-to-Superior ... ... with nifti_image_to_ascii in nifti_io.c I get ... ... qform_code = '1' qform_code_name = 'Scanner Anat' qto_xyz_matrix1 = '-0.874264 0.025372 -0.034796 119.279884' qto_xyz_matrix2 = '0.025372 -0.000368 -1.199495 -111.342300' qto_xyz_matrix3 = '0.025372 0.874632 0.000505 -21.342064' qto_xyz_matrix4 = '0.000000 0.000000 0.000000 1.000000' ... ... qform_i_orientation = 'Right-to-Left' qform_j_orientation = 'Inferior-to-Superior' qform_k_orientation = 'Anterior-to-Posterior' The information fslhd presents is correct, so I don't understand why nifti_io.c gives me the wrong results. Any help is appreciated. Cheers, Ed