Hi Mehul

1 is used so that we can track what is changed (all 1s and 255s are removed beforehand, so everything that is 1 or 255 is edited)

cheers Bruce

On Mon, 26 Aug 2013, Mehul Sampat wrote:

Hi Folks,

I see on the tutorial websites that when voxels are added to wm.mgz or brainmask.mgz, the new voxels are given a value of 255;

while when voxels are deleted, these locations are set to 1.  https://surfer.nmr.mgh.harvard.edu/fswiki/FsTutorial/WhiteMatterEdits

Can the deleted voxels can be set to 0 or they have to be set to 1; Or is 0 used to differentiate the background voxels from brain voxels ?  Thanks Mehul