I’m working on a project what requires around 1 to 2kb of data to be stored for ~80 years.
My thinking was a QR code (ECC H) etched into aluminium. Benefits being no bit rot & the assumption being cameras should still be commonplace in 80 years (And if QR isn’t a commonly used format anymore, surely an AI agent could easily write an app for the user).
Does anyone have any better suggestions or think I’ve missed anything.
Etching aluminium might not photograph with enough contrast to pull out the QR code.
Laser etching glass might be worth a look. You can increase the contrast fairly dramatically with black paint, which can be cleaned and reapplied without damaging the glass.
Is it 1-2kB uncompressed? Because compression will help, the smaller you get the data the larger you can make the QR pixels. You can also split it into 20x100B chunks, and then as long as you number the slides you can rebuild later.
Also, ecc-h only gets you 30% recovery, duplicate or triplicate slides could increase that even further.
I mean you can take a picture and increase contrast. Coat the aluminum black before etching too
Coating would work, but it needs to be permanent, because you can’t easily recoat it. Glass can be recoated on the other side. Dunno how anodising and etching would work, do you get the same color when you etch, or do you get raw aluminium?
I suppose if you scanned the plates in a flatbed scanner that might be even contrast, I was thinking of using a phone camera, and assumed it would be near impossible to get an even lighting across the QR code.
Very interesting, thank you for the advice!
Glass is super underrated for this application because it has the stigma of shattering but high tensile glass with laser etching would last millions of years without degrading.