
The secret codes of British banknotes - williamhpark
http://www.bbc.com/future/story/20150624-the-secret-codes-of-british-banknotes
======
cstross
For real lulz: print this pattern of small yellow dots on all your business
correspondence with big companies, just to screw with their document
management systems. Hours of endless fun for all the bureaucrats!

(There's got to be a PDF/postscript file/print filter for the pattern
somewhere. Anyone? EDIT: Ah, found it here:
[http://wildsparx.com/eurionize/](http://wildsparx.com/eurionize/) \--
download has vanished, but source is on github:
[https://github.com/jplona/code/blob/master/eurionize.pl](https://github.com/jplona/code/blob/master/eurionize.pl)
)

~~~
Someone1234
Or print it on a t-shirt. If anyone tried to capture a screenshot from a CCTV
video feed, well, too bad...

~~~
kaybe
While looking for that I stumbled across patterns and text that only shows up
after photocopying due to effects such as aliasing and low-pass filtering,
also pretty neat!
[https://en.wikipedia.org/wiki/Void_pantograph](https://en.wikipedia.org/wiki/Void_pantograph)

And I easily found some shops carrying shirts:

[http://www.spreadshirt.de/eurion-t-
shirts-C4408A23774319#/de...](http://www.spreadshirt.de/eurion-t-
shirts-C4408A23774319#/detail/23774319T6A2PC120434135PA4PC120434136PA4PC120434137PA4PC120434138PA4PC120434139PA4PC120434140PA4PC120434141PA4PC120434142PA4PC120434143PA4PC120434144PA4)

[http://www.zazzle.com/eurion_constellation_t_shirt-235509764...](http://www.zazzle.com/eurion_constellation_t_shirt-235509764478000766)

if you know German, here are some people from AK Vorrat planning a campaign, I
don't know whether it's still up to date:

[http://wiki.vorratsdatenspeicherung.de/EURion](http://wiki.vorratsdatenspeicherung.de/EURion)

And it has been discussed before, huh:

[https://news.ycombinator.com/item?id=8926114](https://news.ycombinator.com/item?id=8926114)

------
moyix
I've done some preliminary work that measures the amount of "attention" an
image processing algorithm pays to a given pixel (in terms of amount of
computation done on it). Hard to tell at the moment how well it's working, but
the results for the £10 note do seem to focus more on a region that includes a
Eurion:

[http://laredo-13.mit.edu/~brendan/eurion_psp_gaze.png](http://laredo-13.mit.edu/~brendan/eurion_psp_gaze.png)

(This is from Paint Shop Pro, version 8.0, which refuses to edit the above
image)

~~~
jgrahamc
How are you measuring that?

~~~
tacone
I found these videos on his website:

[http://laredo-13.mit.edu/~brendan/eurion_attention.mp4](http://laredo-13.mit.edu/~brendan/eurion_attention.mp4)

[http://laredo-13.mit.edu/~brendan/eurion_tcn.mp4](http://laredo-13.mit.edu/~brendan/eurion_tcn.mp4)

~~~
moyix
Yup. These weren't as exciting as I'd hoped. The former (eurion_attention.mp4)
basically shows a sliding window of what pixels had computation done on them
over time; the most recent 1000 bytes (~330 pixels) get "lit up" in each frame
of the video. You can see in the early part of the video how it scans over the
image multiple times, but the later parts are not very interesting (and the
whole thing is absurdly long; I recommend watching at 50X).

The second (eurion_tcn.mp4) one is simpler, and just tracks the mapping
between pixel and compute number [1] over time.

[1]
[https://news.ycombinator.com/item?id=9778871](https://news.ycombinator.com/item?id=9778871)

------
DanBC
It's not just EURion though.

[https://news.ycombinator.com/item?id=7006848](https://news.ycombinator.com/item?id=7006848)

[http://www.cl.cam.ac.uk/~sjm217/projects/currency/](http://www.cl.cam.ac.uk/~sjm217/projects/currency/)

------
jgrahamc
This describes the geometry of the EURion constellation: "Recognizing Banknote
Patterns for Protecting Economic Transactions"
[http://paginaspersonales.deusto.es/igor.ira/publications/201...](http://paginaspersonales.deusto.es/igor.ira/publications/2010/text/igor.ira_Recognizing_Banknote_Patterns_for_Protecting_Economic_Transactions.pdf)

This patent describes how it is recognized:
[https://www.google.com/patents/US20060279767](https://www.google.com/patents/US20060279767)
The short version of which is "find all the circles, measure the distance
between them; if you find five with the right distances you've found EURion".

~~~
SilasX
So wait it doesn't account for dense circle patterns? Like if I have a bunch
of circles, then it rejects the image if _any_ five of them have bad
distances? I would think it would account for blank space somehow.

~~~
jameshart
Suggests a way to DOS an image processing application by including a lot of
circles, too

------
Zarkonnen
Ah, good old Markus Kuhn. Always up for poking security features using any way
possible. If you're interested in this kind of thing, you should read
[https://www.lightbluetouchpaper.org/](https://www.lightbluetouchpaper.org/)
which is UoC's security research blog.

------
shiggerino
While I agree with the law, I take exception to my own possessions being
hijacked for law enforcement. Apparently there's no need for a warrant to
sneak in robotic cops in people's homes and offices.

------
jgrahamc
BTW If you are interested in stories about counterfeiting currency I can
recommend: The Art of Making Money: The Story of a Master Counterfeiter

[http://www.amazon.com/The-Art-Making-Money-
Counterfeiter/dp/...](http://www.amazon.com/The-Art-Making-Money-
Counterfeiter/dp/1592405576)

------
mapleoin
Meanwhile, the rest of the world is switching to plastic banknotes:
[https://en.wikipedia.org/wiki/Polymer_banknote](https://en.wikipedia.org/wiki/Polymer_banknote)

~~~
teddyh
…except Europe.

~~~
jmkni
Northern Ireland was actually the first part of the UK to have these, they
were introduced back in 2000 to celebrate the new millennium, you can still
find them in circulation.

~~~
AlecSchueler
Can you? I don't think I've seen one for maybe 10 years.

~~~
jmkni
I had one a couple of weeks ago, next time I get one I'll hang onto it I
think.

------
wereHamster
I can't find this pattern on swiss bank notes. Any idea if the swiss bank
notes can be copied on xerox machines? Or do the swiss banknotes use a
different pattern?

------
cordite
Hmm, my $1 and $2 bills don't have this, though my $5, $10, and $20 have
something like this with the O's (05 for $5)

------
gadders
This is not news, is it? I remember reading about this pattern of circles 5+
years ago.

~~~
misnome
Five years? According to wikipedia it's been around since 1996.

------
stefantalpalaru
You can't falsify banknotes with regular printers and regular paper, but you
may need to scan and print them for some art project in which case you should
just use Linux and avoid those silly protection measures.

~~~
cstross
Ahem: you can't falsify banknotes with regular printers and commodity paper
_well enough to fool an alert human being_ , but the scanners in some vending
machines are another matter. With 7 colour 1200+ dpi inkjets readily available
for photo printing, if you could find a vaguely passable source of paper you
could do wonders -- and one option forgers have used is to take low value
notes and bleach them before overprinting with a higher denomination print
pattern. (I think this is the rationale for high-denomination Euro banknotes
-- €50 and above -- having embedded RFID chips.)

~~~
raverbashing
> used is to take low value notes and bleach them before overprinting with a
> higher denomination print pattern. (I > think this is the rationale for
> high-denomination Euro banknotes -- €50 and above -- having embedded RFID
> chips.

Citation needed

You can't take a lower denomination bank-note and print a higher denomination
one on an Euro note: the sizes are different (of course, maybe you can pass
one note for the next in sequence, but it is slightly harder)

Also no RFID is mentioned here
[https://en.wikipedia.org/wiki/Euro_banknotes#Security_featur...](https://en.wikipedia.org/wiki/Euro_banknotes#Security_features)

~~~
arethuza
I always thought the coolest thing about Euro notes is their use of traces of
the element Europium:

[https://en.wikipedia.org/wiki/Europium](https://en.wikipedia.org/wiki/Europium)

