Do black and white laser printers produce tracking dots?
Also, what is the meaning of this tracking, must every corner of our lives be tracked just on principle?
I can't affirm knowledge of steganographic identifiers in B&W printers. I wanted to state I would be surprised if B&W printers did not embed tracking information. There's too much national security value in spamming origination details on everything. There is always, always a safety or security argument to do so, followed with "but what's the harm, you're not doing anything you shouldn't be doing... are you? "
It's my understanding that the secret service requested (required?) that the printer manufacturers start adding the dots once the printers got good enough to easily recreate paper bills. Because they are primarily a tool for tracking counterfeiters, they are not needed with black a white printers and thus are not included.
The tracking dots aren't for anti-counterfeiting. The secret service has a separate chunk of code in every color printer that detects if you are printing money and prints out a page that says essentially, "you can't do that." (at least that was the case 20 years ago when I worked for HP).
The tracking dots are used by the FBI if someone prints out classified information and passes it around, or other copyrighted/illegal documents.
The EURion constellation[0] is how that detection mostly works as I understand it. Neat bit of tech. It's real obvious on euro bills once you know what to look for. Fun fact: not all printers give a hoot about this pattern, so it's a neat trick to annoy people with if your printer doesn't.
mostly, the software in printers/scanners and Adobe's Photoshop alikes is looking out for the "EURion" pattern.
https://en.wikipedia.org/wiki/EURion_constellation
That is not to be confused with (dynamical) and non-visible tracking info on printed sheets, which in fact can have everything coded in. By that, even 1-bit printouts can be identified up to the source. If the printer model and #salt is printed alongside, the prosecution has evidence for the cases the printer involved.
https://www.eff.org/pages/list-printers-which-do-or-do-not-d...
List hasn't been updated since 2017, was probably one guy making inferences from FOIA requests. We'll have to wait until the next time a Chinese university publishes some US government secrets.
I think the idea is that nobody is going to be fooled by a B&W $20 bill, so they don't have to print the dots.
No yellow dots on monochrome printers.
Decades ago I worked on some software that would adjust the kerning on characters to hide information. As far as I know the project never went anywhere.