DARPA’s Shredder Challenge, a contest to reconstruct documents from a slurry of shredded paper, has been solved, suggesting that my grandmother may be barking up the wrong tree when she shreds the Campmor catalog. Three scientists with experience in computer vision and mobile technology, Otavio Good, Luke Alonso, and Keith Walker, scanned each chunk for unique characteristics that allowed them to reconstruct the documents automatically on screen. They then put the pages back together by hand.

Their team won a $50,000 prize.

The contest consisted of five different documents (you can try a demo here but rest assured the real ones were a bit harder) and teams were a race to reconstruct them as quickly as possible.

So should gam-gam – or you – keep shredding documents? Good told the New Scientist:

So with DARPA’s documents reconstructed, are shredders now insecure? No, says Good. “The challenges that DARPA gave us were actually simple compared to if you have a bin full of lots of shredded pieces of paper. Reconstructing these documents was not easy at all. I don’t think you have much to worry about with your shredded documents.”

Looks like your secrets are safe… for now.