[Insight-users] 3D image registration memory problem

[m.weigert at fz-juelich.de]

Hi Zehor,

I use the same configuration as you do and have 
a similar problem.

The registration runs only, when I use a very
few spatial samples (say 100 000 for an 512 x 512 x 120  CT and 377 x 275 x 121 MR image as fixed and moving image respectively) for Mattes MI calculation.
I receive the error-message "could not allocate memory for image", and the registration stops for more samples.
Unfortunately, this is a drawback for this method, which shows really good results, but is a little bit
problematic with large volumes.
I don't know if memory usage of the registration framework could be tuned some way, but I think this
is a common problem with BSpline - Transform because
for other transform (like translation), I do not receive this message for higher number of samples for Mattes MI.
Also, I have to deal with images of this size quite often and sometimes, my system  (1GB RAM) even runs out of memory when I try to resample the images to a lower resolution for better handling.

Regards,
Markus