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Can’t watch YouTube.
How do black and white laser printers print yellow dots if there’s no yellow toner?
aka MIC (Machine Identification Code)
https://dys2p.com/en/2022-09-print-scan-traces.html#mics-eigene-untersuchungen
Dys2p did a great write up about it
I have a printer?
if you don’t wanna watch a vid… eff has posted several articles over the years on the ‘tracking dots’ of printers: https://www.eff.org/issues/printers
Even this cutie pie?
That one will just stab you in your sleep, so you should be good.
Just get a laser printer already
I have a color laser printer. :/
You can use a blacklight to see if the printed page has the tracking dots.
It’s an hp. I just assume it does.
I should inspect my black & white printouts for the yellow dots. Alternately I guess I could remove the color cartridges.
That’s why a lot of printers refuse to print in black and white when color cartridges are empty.
There are exceptions but it is the case for a large amount of printers
Could this be solved with software that would just print its own random yellow dots to make the code unreadable? At the cost of wasted ink
Nowadays though, they are wifi-ied. So they are ratting you out in other ways too, not just the paper markings, you can bet.
Only the dots in a certain place in a certain pattern are used to track the printer. Any other dots aren’t useful for that purpose and can be ignored. If you printed a solid block of yellow at the correct location, however, the tracking dots might be indistinguishable.
Thinking more about your (and TU Dresden’s) idea, circumvention would be a nice ability to have as standard functionality in linux printer drivers.
I wonder if inkjets do this too. I have only heard it in the context of color lasers, and that’s all the wikipedia page says. But IDK why they wouldn’t also add it to inkjets.
That’s an interesting idea.
The wiki page says the pattern is repeated about 150 times on a standard page, so it is fault tolerant. In theory, a printer could also dynamically relocate them. To avoid regions of yellow. But if there was no dynamic reloc, then you could overwrite.
Wikipedia thinks you are onto something!
In 2018, scientists from TU Dresden developed and published a tool to extract and analyze the steganographic codes of a given color printer and subsequently to anonymize prints from that printer. The anonymization works by printing additional yellow dots on top of the printer’s tracking dots. The scientists made the software available to support whistleblowers in their efforts to publicize grievances.
Oh, paper printers
