The iOS Mobile Backup Xtractor.
It extracts backups... and stuff.

Binary releases for macOS: here.

FYI: On macOS, iTunes places backups in ~/Library/Application Support/MobileSync/Backup. ;)

As always:

make

Usage:
    ./imobax [-f] [-i] [-l] source-dir [target-dir]

Options:
    -f  Force overwriting of existing files
    -i  Ignore missing files in backup
    -l  List contents only, write nothing

MPL2 with Exhibit B.