The possibility of making money from shredded banknotes using computer vision
arxiv.org
arxiv.org
I wonder how much the state of the art in reassembling shredded documents has advanced since then...
https://web.archive.org/web/20120126014654/http://www.shredd...
The lead borders follow smooth arcs, so the glass may have been ground down to fit the existing shaped holes, causing a lot to be lost.
The caption seems to suggest all of the windows were broken, but only one side of the church was reconstructed with all of the pieces. So that's 3/4ths lost there, possibly.
I could see computer vision finding the orientation of symbols and faces, and gathering similar patterns. I'm not sure how much farther it would get though.
I think something like this is unfortunately doomed to fail, as whilst there might ideally be approximately 138 banknotes worth of mass in there, it seems likely that the shreds are from thousands of different banknotes, and the container holds only a fraction of each whole note. Therefore no matter how good your reconstruction is, you simply won’t have the right pieces to work with.
Could probably be improved by doing 50-100 variations on each bill to give a general idea of the patterns possible within a zone. Such as: This area has 8 possible characters, with 36 possible entries /[a-zA-Z0-9]/. It has a fixed border with some constant pattern nearby. Show all the possible combos and then dice up the area a bunch of different ways.
On the partial constructions topic:
You have 350 of 1000 pieces of an image with some known general shape.
How much of the image can you reconstruct while still missing 2/3 of the pieces?
At the least has applications for image guessing. Also, agree on the false bank note contents, and how many people at the note shredding office are just stuffing their pockets with bank notes and then filling the cylinders with rocks? Great scam that probably almost nobody actually checks.
Why not incinerating, dissolving in acid, grinding into a fine powder, or something like that?
My pet theory is big companies first shred and after send to be burned (or recycled).
Plus a shredding machine us safer than a fire device.
But yes, paper that's shredded by a specialist paper-shredding company is then typically baled up and sent for recycling.
And whenever I need to dispose of something I can’t compost, like an old drivers license, I cut it into pieces and drip feed the pieces into the garbage over the course of a few months.
Call me paranoid but I think there will be a cottage industry in sifting through garbage once this tech gets mature enough!
You're being very, very excessively paranoid doing anything more than just cutting it into a piece or two across the ID number.
That seems like both more effort, and potentially less effective, than just burning them?
Having sensitive data compromised would make me extremely sad.
https://www.nytimes.com/1986/07/10/world/7-years-after-embas...
>Among the most interesting papers are shredded secret documents pieced back together by the militants that detail attempts of the Central Intelligence Agency to recruit high-level Iranian officials, ayatollahs and exiles, foreign journalists and diplomats either as paid or ''unwitting'' agents in the months after the revolution in February 1979.
https://en.wikipedia.org/wiki/Paper_shredder#/media/File:Shr...
It doesn't look like the embassy was even using a cross-cut shredder.
According to https://www.whitakerbrothers.com/pages/paper-shredders-secur... it was already up to p6-7, at least for everything I saw.
There would always be signs posted warning against wearing a tie while using the shredder.
Even if only, I don't know, 1/4 of the pieces are there, the potential to turn $13 into $4.5k isn't bad at all.
The trick, then, is to collude with other souvenir purchasers, similar to McDonald's Monopoly, so you can quickly swap your own duplicate pieces to others who need them. But unlike Mcdonald's Monopoly, there's probably no rare Park Place that virtually guarantees an instant win to whoever holds it.
The bank could do something like that. They could cut all the bills in two, and incinerate the left 60% of every single bill, so the souvenirs only contain shreds of the right 40%, thus guaranteeing that nobody can ever reconstruct 51% of a bill no matter how many souvenirs they have. But there seems to be no evidence that they're doing this.
I was hoping the author managed to buy the last 100 of them and is selling them at HKD 5000 each to people who read this paper and want to try their luck.
It's like revoking a TLS cert. It was once real. Now it's not.
https://www.bep.gov/services/shredded-currency-distribution#....
https://www.bep.gov/services/mutilated-currency-redemption#:...
That doesn't mean it's _not_ illegal, but it does tend to confirm my suspicion that nobody has thought to worry about it.
However, I am not a lawyer but I'd bet a court would rule that the act of shredding the currency was intended to permanently invalidate its use as currency, and any attempt to reverse that shredding via reassembly, combined with an attempt to pass off said reconstituted money as US currency, would constitute fraud. So while the rules don't seem to explicitly say you can't do it, it's implied that you can't.
Sadly it all got burned up in a fire last year.
I recommend going, if you’re ever in the vicinity of one. There will be all sorts of rare and obscure currency, plus odd things like stacks of $1,000,000 in various denominations for you to take photos with.
Hong Kong Monetary Authority admits short-changing buyers of shredded banknote paperweights found to be light on cash content
https://www.bankofengland.co.uk/banknotes/damaged-and-contam...
The form says you need to provide ID if it's £700 or more, and they need witnessed ID for £10 000 or more for AML reasons, sadly you can't apply in person so no tearing up banknotes and popping into Threadneedle Street to do it on the spot as a tourist.
As that link mentions if the problem with your "damaged" note is that it was in a dye pack which exploded during your bank robbery, that's not an "accident" and you don't get an undyed replacement note - you're a crook, if you weren't smart enough to give a fake name and address you're getting arrested.
https://www.cbc.ca/radio/asithappens/dog-eats-cash-1.7075889
https://www.stasi-unterlagen-archiv.de/archiv/rekonstruktion...
Edit: link to the English version.
In the 1990s, the Stasi Records Archive began reassembling documents that had been torn up by hand by the staff of the Ministry for State Security (MfS). This material had been stuffed into a total of 16,000 bags.1.7 million pages from 600 bags have been manually reconstructed, indexed and archived. Additionally, as part of a pilot project, a computer-assisted reconstruction program reassembled approximately 91,000 pages from 23 bags.Arxiv does this presumably because some papers have mathematical expressions in the titles and abstracts. For example https://arxiv.org/abs/2401.04991
You'd think they'd have no problem being honest about the count since they must shred a huge number of bills daily due to normal bill lifecycles, or that people would've shaken the containers and noticed, but apparently not!
It would be pretty funny if there was some kind of scam going on here where the notes were actually being reconstructed and a small portion of each paperweight was siphoned off to support the crime (perhaps by diverting whole notes early in the shredding process). That could explain why some weights had fewer notes with rocks to make up the difference. Seems unlikely obviously in reality but there should probably be an investigation to figure out why the Hong Kong Monetary Authority visitor center is participating in fraudulent behavior.