Dear SPM experts,
I am trying to figure out the differences between "old segment" (SPM8) et "new segment" (SPM12). In the documentation, I saw that it is the same algorithm with some minor differences (such as additional tissue classes). I would like to be able to segment with "new segment" using a template potentially consisting in less than 6 classes.
As a test, I tried to segment with spm12 but using the 3-classes template from SPM8 (GM,WM,CSF), the segmentation was wrong. I then tried to add a fourth class equal to one minus the sum of the 3 others, It did improve a bit but was still quite bad.
You can see here some images illustrating what I got : https://perso.univ-rennes1.fr/pierre.maurel/spm12/comparison_segment.png
I also tried to play a bit with the "number of gaussians" parameter without success.
Is there something I missed ? Or is the "new segment" really optimized to be used with 6-classes only ?
bests,
Pierre
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