I think you're thinking of dvdisaster, whose site is defunct, though it's been forked on GitHub. I'd suggest par2 instead, as you can separate the recovery files from the media.
You're right. I was thinking of dvdisaster. My mistake.
However, par2 is not a substitute for it, as without the kind of ECC that dvdisaster puts on the CD/DVD, the files on it might not even be readable, so the par2 files on it would themselves be inaccessible, making them worthless.
When I mentioned separating the recovery files, I meant "burn them on the media and also copy them somewhere else." I think par2 can pull data from a re-ripped iso even without, say, legible file names.
