On 04/24/2013 11:14 PM, Dana Wagshal wrote:
> Hi FSL group,
>
> I have ROIs in 2mm MNI standard space and I want to convert them TO 1mm MNI space. I used this command:
>
> flirt -in lACC.nii.gz -ref /usr/share/data/fsl-mni152-templates/MNI152_T1_1mm_brain -applyxfm -out lACC_1mm
>
> However, when I typed in fslinfo for both the original and new ROI, I saw that the dimensions were changed. Is this ok or should the dimensions be the same?
If you mean by dimension the dim values, it is to be expected, that you
need double the voxel to cover the same volume if you use half the voxel
size. For ROI masks it might be good to binarize them (fslmaths -bin).
Otherwise if the transformed ROIs look on a 1mm standard brain the same
as the olf ROIs on a 2mm brain, it should be fine.
Good luck,
wolf
>
> Below is the information:
>
>>> fslinfo lACC-new.nii.gz
> data_type INT16
> dim1 91
> dim2 109
> dim3 91
> dim4 1
> datatype 4
> pixdim1 2.0000000000
> pixdim2 2.0000000000
> pixdim3 2.0000000000
> pixdim4 0.0000000000
> cal_max 4.0000
> cal_min 0.0000
> file_type NIFTI-1+
>
>>> fslinfo lACC_1mm.nii.gz
> data_type FLOAT32
> dim1 182
> dim2 218
> dim3 182
> dim4 1
> datatype 16
> pixdim1 1.0000000000
> pixdim2 1.0000000000
> pixdim3 1.0000000000
> pixdim4 0.0000000000
> cal_max 0.0000
> cal_min 0.0000
> file_type NIFTI-1+
>
> Best,
> Dana
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