dmg2img : a tool which allows converting Apple compressed dmg archives to standard (hfsplus) image disk files ( ttps://github.com/Lekensteyn/dmg2im )
dvdisaster : Tool for creating error correction data (ecc) for optical media (DVD, CD, BD) ( http://dvdisaster.jcea.es/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a salfter
For Paludis use this rsync : rsync://gentoo.zugaina.org/salfter-portage
If you have a problem : ycarus(-at-)zugaina.org