I'm having trouble with scaling some PET images. What I'm trying to do
is scale them to their respective overall mean so I can calculate a
template image for FLIRT registration.
I masked out all values <=0 with avwmaths -thr 0 and then calculated the
mean of the remaining voxels with avwstats -M. Now, I'd like to divide
my data by that factor to achieve scaling to the mean. When I do the
avwmaths -div, the scaling factor (funused1?) is not adjusted, and the
effect is quite deleterious. I've made a picture and put it to
Is there a way to get around this issue? And what happens when I sum the
mean-scaled images up, are the individual scaling factors respected?
I'd appreciate any comments.