Hi Suzan, 

actually it uses rigid within-subject registration. 
The transformation files should be in ./mri/transforms (in long and in base). 

Best, Martin


On 17. Mar 2021, at 23:05, Douglas N. Greve <dgreve@mgh.harvard.edu> wrote:

Where is the non-linear registration coming from? Our long stream uses affine.

On 3/11/2021 2:59 PM, Suzan Maleki wrote:
Hi FS experts,

I appreciate it if you help me with a question on your longitudinal processing pipeline. If I use FreeSurfer to generate an unbiased T1 image template from N time points (non-linear registration), then how can I apply the within subject transformation matrix (Jacobian matrix) to that subject's DTI maps. 
Does FreeSurfer save the transformation matrix from N.Time-Points toward Template image? and if so, in which folder directory it will be saved? 
Also, given that FS uses vertices, should I first convert that transformation matrix to voxel space  (eg. using surf2voxels ?) and then multiply that into different time-points of one's DTI images.
Hope my questions are clear and looking forward to hearing from you:-)

Best 
Suzan 
--
Suzan Maleki
PhD Student

Brain, Mind and Society Research Hub
Turner Institute for Brain and Mental Health
School of Psychological Sciences
Monash University
770 Blackburn Road
Clayton VIC 3800 Australia


_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer