[Insight-users] ITK Image Memory Layout (now as text)

[John Drescher]

> First I have to apologize my first post this morning which was sent as
> html by accident :( . Sorry!
>
> I am very new to ITK and have a probably very simple question I could
> not find a clear answer for using google and the standard
> documentation (I also skipped through the Doxygen documentation, but I
> was not able to dive into the code as deep as the answer to my
> question would require :( ).
>
> 3D data typically requires large amounts of memory - in the orders of
> 100MB - 1000MB . It is typically not a good idea to allocate data
> ranges that large as a single big chunk of memory.

I would think this would be a problem mostly on 32 bit systems or
compiling for 32 bit on 64 bit systems. If you can go to 64 bit. I
have moved a few years ago and its much easier not to worry at all
about running out of contiguous address space.

>So I wonder: If I
> set up a large 3D image with ITK - is the memory split up internally
> (like volume slices or whatever)? Or does ITK try to do something like
> (probably a bit oversimplified, but it should make clear what I mean)
> :
>
> float *p = new p [1024*1024*1024];
>
This is the way itk::Image allocates its memory.

http://www.kitware.com/products/html/AlternativeMemoryModelsForITK.html

John