How to register a tensor to a scalar image

Submitted by liuc15 on

Dear Okan,


I have a tensor image generated by DR TAMAS. I want to transform this tensor image to a scalar image template (T1 or T2).


What command should I use?


I tried used DTIREG:


DTIREG --moving_tensor tensor.nii --fixed_scalars T1_template.nii


But it was not working.


Should I use the tensor to generate a FA image, and then use ANTS to transform the FA to the T1_template.nii, and then use DR TAMAS to read the transformation from ANTS and apply it to the tensor?

Can DR TAMAS read the transformation files from ANTS?


Or there is a more direct way to do it?


Thanks a lot!




Submitted by nayaka on Thu, 06/06/2019 - 11:22



There are several ways in DRTAMAS to co-register the DTI and T1/T2 template. To address your question, it would be helpful to know if your ultimate goal is to co-register the templates or specifically bring the DTI template into the T1/T2 template space?


Submitted by liuc15 on Thu, 06/13/2019 - 15:02

In reply to by nayaka



I have created a T1/T2 template using ANTS, and DTI template using DRTAMAS.


Yes, I want to bring the DTI template into the T1/T2 template space.

Submitted by irfanogl on Thu, 06/13/2019 - 15:13



DRTAMAS is again for tensor operations only.  So what I suggest is to ComputeTRMAp (Trace or in otherwords MD), out of the tensor template. Then use ANTS to register this on to your T1/T2 template.

Then you can combine the affine/diffeomorphic transformations coming out of ANTS and Apply the Transformation to DRTAMAS tensor with "ApplyTransformationToTensor"


hope this helps.




Submitted by irfanogl on Thu, 06/13/2019 - 18:03


Sorry should have given more details.


First you need to convert the affine_transform.mat into a txt with:

ConvertTransformFile 3 affine_transform.mat affine_transform.txt

Then you can use CombineTransformations:

CombineTransformationsWithOutputName -out combined_deffield.nii.gz -trans affine.txt diffeo.nii.gz

Then you can apply it:

ApplyTransformationToTensor  average_template_diffeo_6.nii  combined_deffield.nii.gz average_template_diffeo_6_tranformed.nii  FS your_T2_template.nii

hope this helps.