The Advanced Forensics File Format 4 (AFF4) is an open source format used for the storage of digital evidence and data.
It was originally designed and published in  and has since been standardised as the AFF4 Standard v1.0, which is available at https://github.com/aff4/Standard. This project is a work in progress implementation, providing two library implementations, C/C++ and Python.
The focus of this implementation is reading physical images conforming with the AFF4 Standard v1.0, and for the ongoing development of an AFF4 based logical image standard.
Canonical images for the v1.0 physical image specification are provided in the AFF4 Reference Images github project at https://github.com/aff4/ReferenceImages
The write support in the libraries is currently broken and being worked on. Other aspects of the AFF4 that have not yet been implemented in this codebase include:
This is not an official Google product (experimental or otherwise), it is just code that happens to be owned by Google and Schatz Forensic.
 "Extending the advanced forensic format to accommodate multiple data sources, logical evidence, arbitrary information and forensic workflow" M.I. Cohen, Simson Garfinkel and Bradley Schatz, digital investigation 6 (2009) S57-S68.