Investigating the itk Python interface is worthwhile. The latest and greatest will be available in Python packages for the upcoming ITK 5 Beta 1 release. This will include the Pythonic interface to ITK filters and NumPy @blowekamp mentioned
Additionally,
- There are a number of Remote Module Python packages available.
- There is support for meshes, point sets, paths, and other data structures.
- There is support for streamed processing, which helps process very large images on computers with limited amounts of memory.