My initial guess is that the display nodes are still holding registered pointers to the image data even when the volume has been deleted.

I wonder if we should explicitly remove any of the referenced display nodes when the user deletes the node from the Data module (since it's possible, though unsusual, that the display node could be shared, we could check to see if the display node is used by any other node before deleting it).

A related report:

Hi,

I am using Slicer to load detailed CT-images of femur bones and loading one image is quite challenging with a 4GB RAM computer.
Anyway I manage to do that. Well, I manage to do that once... I have noticed that when I close the scene the memory is not freed and if I try to load another image I have an error message.

If I try to load the image just after relaunching Slicer it works...
I believe there is some cleaning of the memory missing after the scene is closed. Could I do something to help the process a bit?

Cheers,

Morgan Sangeux

Senior Biomedical Engineer
Royal Children's Hospital
Melbourne - Australia

Re-target since require more research.

Added logic to remove display and storage nodes when displayable node is removed.
This should delete image data associated with volume node.
Rev 21528.

Closing resolved issues that have not been updated in more than 3 months