The Python File Format Interface, briefly PyFFI, is an open source Python library for processing block structured binary files:

• Simple: Reading, writing, and manipulating complex binary files in a Python environment is easy! Currently, PyFFI supports the NetImmerse/Gamebryo NIF and KFM formats, CryTek's CGF format, the FaceGen EGM format, the DDS format, and the TGA format.
• Batteries included: Many tools for files used by 3D games, such as optimizers, stripifier, tangent space calculator, 2d/3d hull algorithms, inertia calculator, as well as a general purpose file editor QSkope (using PyQt4), are included.
• Modular: Its highly modular design makes it easy to add support for new formats, and also to extend existing functionality.

Get PyFFI from Sourceforge, or install it with:

easy_install -U PyFFI

To get the latest (but possibly unstable) code, clone PyFFI from its Git repository:

git clone --recursive git://github.com/amorilia/pyffi.git

Be sure to use the --recursive flag to ensure that you also get all of the submodules.

If you wish to code on PyFFI and send your contributions back upstream, get a github account and fork PyFFI.

• The Blender NIF Scripts and the Blender CGF Scripts use PyFFI to import and export these files to and from Blender.
• QSkope, PyFFI's general purpose file editor.
• The niftoaster (PyFFI's "swiss army knife") can for instance optimize nif files, and much more.

• Open an issue at the tracker.