Hi,
I am new to AFNI and I am trying to get a transformation matrix to convert points of interest.
The points were chosen on anat+orig file and I want to transform them to ortho_orig coordinates.
The ortho+orig file was created by using TAGALIGN and then I used the nudging tool.
I tried the following but the transformed point doesn’t make sense.
nudge_rot_mat*(TAGALIGN_MATVEC_mat(:,1:3)*anat_pnt’+TAGALIGN_MATVEC_mat(:,4))+nudge_shift’;
Am I missing something?
I’m not clear as to what you’re trying to do. With the tagset plugin, you would set your points in the exact same order for two datasets. Then use 3dTagalign to affinely align one dataset to the other. The affine transformation is computed and stored in the header of the dataset. You could use the Nudge plugin afterwards too. cat_matvec can concatenate the two transformations together. You may then apply the transformation with 3dAllineate or 3drotate. Directions of the transformation matrices are important here, so you have to be consistent, and you may need to take the inverse of each.
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