[MINC-users] Question about mincmath

[(Jessie) Ting Guo]

Hello,

I want to create a digital phantom, but have some problem with "mincmath".

I have two images and want to use mincmath to add them together. The
background of the two images are 0. Image A contains a big ellipsoid with
grey level of 110. Image B contains two small spheres with grey level of
145. When the two images overlap, the two small spheres are within the
ellipsoid.

mincmath   -add   ImageA   ImageB   ResultImage

I expected that the resultant image would have background with grey level of
0, the ellipsoid with grey level of 110, the regions of spheres with grey
level of 255 (110+145). However the actual result is not like what I
expected. The spheres are with grey level of 255, several slices of the
ellipsoid which contain the two spheres are with grey level of 110, and the
rest slices of the ellipsoid have grey level of some value lower than 110.

Could anyone help me?

Thank you very much!
Jessie