\n", "If the segmentation step fails, this may be due to insufficient contrast between the tissue types; for example, some anatomical images are either very dark across both the grey and white matter, or very light across both tissue types. We can help the segmentation process by increasing the intensity contrast (also known as intensity normalization) between the tissues with a command like AFNI’s 3dUnifize, e.g.
\n", "3dUnifize -input anat.nii -prefix anat_unifize.nii
\n",
" The difference between the image before and after may be subtle, but it can prevent a segmentation error from being thrown.\n",
" \n",
"