MubDub is something I hacked together in two part-time days to rescue about 200 photos that had mysteriously disappeared from my iPhone. The technical details were gleaned from iphonebackupdb.py.
Use at your own risk. Don't use it without at least partially understanding the code.
Only runs on OSes that support hard links.
MubDub parses the Manifest.mdbd and Manifest.mdbx files in the working directory to map the SHA file names used in the archive to human-readable file names. Then it sets up a directory structure with those file names hard linked to the original SHA-named files. This allows you to move those files wherever you want and then throw away the archive if so desired.