[Insight-users] itk::octree

[motes motes]

I am looking at itkOctreeTest.cxx which runs a test on an octree. The
octree is build from a 3D image where each pixel has a value.

My question is now. Is it possible to use the above octree as
structure to find the k-nn to a point p?

Assume that we have a 3D image which contains 12*12*12 nodes
distributed randomly in the volume. Now for a given point p in the
volume, the nodes within a specified radius r should be returned.

As I understand the octree returns values of pixels and not locations
but maybe with some modification it could be possible to convert this
into locations? Does anyone have an idea for this?