input
    group-{group}
        sub-{subject}
            group-{group}_sub-{subject}_T1w.nii.gz (T1w)
output
    group-{group}
        sub-{subject}
            T1w_brain_first_attempt.nii.gz
            T1w_cut.nii.gz
            T1w_brain.nii.gz
            ->fast basename=run_fast (segment)
            xfms
                gm_pve2standard.mat (linear_reg)
                gm_pve2standard.nii.gz (nonlinear_reg)
                gm_pve_in_standard.nii.gz (gm_pve_in_standard)
                gm_pve_in_template.nii.gz
                gm_pve_jac.nii.gz
            gm_pve_mod.nii.gz
    template
        gm_pve_avg.nii.gz (gm_pve_template)