Things have taken a somewhat unexpected turn, as it turns out the reason the disks weren't working in the first place is because the drive in the Disklavier piano was shot. This evening I was able to swap out the floppy drive for a new one (expect to see more about this...), and it's now able to read all of the disks without issue. Suddenly, the need to back-up these disks seems much less urgent.

Especially considering what else was discovered tonight. It turns out that for whatever reason, simply writing the images made with ddrescue back to known good floppies doesn't work. The Disklavier says they are unformatted disks. This means one of the core goals, that is, to preserve these commercial Disklavier floppies, is in jeopardy until we can figure out how to actually put them back onto physical media.

So, that being said, what is the status of the actual software? As of right now, the Python program I've written is able to identify and extract individual tracks from all but one of the disks we've currently made images of. The problem disk may be defective or a fluke, as it has some very unusual formatting issues that don't appear on any of the others.

I plan on doing some more testing soon, and may end up grabbing a few more of disks off of eBay to collect more data, but an initial release of the tool on GitHub should be coming pretty soon.