Dear everyone,
I use the SPM5 for segmenting the brain tissues. I believe the mg, mn,
vr fields in the resultant files *_seg_sn.mat are the parameters of the
Gaussians used for modeling the density distribution of tissue
intensities, that are weight coefficient, mean and variance respectively.
I guess the probability density function of the intensity values in the
volume is estimated by this formula. If i am wrong please correct me
pdf = SUM { mg(i) * N(mn(i), vr(i)) }
(the summation is over i`s.)
I have two questions about them.
1- Why these parameters vary between the *_seg_sn.mat files for each tissue?
2- The fitted intensity distribution of the volume belongs to the
original volume to be segmented or the bias corrected volume?
Thanks for your help in advance
Burak
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