Value of voxels in segment mgz files from Freesurfer

Hi, this is a primary question. After recon-all, we’ll get some segment files like aseg.mgz, aparc+aseg.mgz, if the value of each voxel equals the index in the FreesurferLut file, like an ID.

Yes, the intensities in those files correspond to regions in color look up tables: FsTutorial/AnatomicalROI/FreeSurferColorLUT - Free Surfer Wiki.