Transforming Fibers to MNI space

[Luie Wang]

Hi all, 

I would like to normalize each subject's fiber group to MNI space so I can make a average fiber density map per group. I see on Vista Lab Wiki that one approach to do it is to use dtiXformFiberCoords but its usage as shown in this link : https://github.com/vistalab/vistasoft/blob/master/mrDiffusion/xform/dtiXformFiberCoords.m is not very clear to me. I tried the example and it didn't work out. Can anyone help me with it or explain it further? Is there other way to normalize the fibers besides dtiXformFiberCoords? (I tried normalization with FSL's fnirt but there's slight misalignment for a few subjects). 

Thank you so much !

Best,

Luie