I am trying to register an anatomical ROI (V1Left.nii.gz) in the same volume space as brain.mgz for SubjectX using spherical registration to the average subject brain. I have used the following command

mris_preproc --s SubjectX --out ~/SubjectX/lh.ave.v1.mgz --target average --hemi lh --ivp ~/SubjectX/V1Left.nii.gz ~/SubjectX/mri/transforms/identity.xfm

and received this output:

nsubjects = 4
ERROR: number of input volumes (1) does not equal number of subjects

From where does the code read nsubjects = 4?

Thanks for the help,

Holly Bridge



If required, identity.xfm contains the following 

MNI Transform File
% tkregister2

Transform_Type = Linear;
Linear_Transform =
   1.00000000    0.00000000    0.00000000    0.00000000 
   0.00000000    1.00000000    0.00000000    0.00000000 
   0.00000000    0.00000000    1.00000000    0.00000000 ;

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Dr Holly Bridge


Royal Society University Research Fellow        

FMRIB Centre                            Tel: +44-1865-222582

John Radcliffe Hospital

Headington

Oxford OX3 9DU            Email: hb@fmrib.ox.ac.uk


Lecturer and JRF, New College

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