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586 points prawn | 1 comments | | HN request time: 0.205s | source
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schoen ◴[] No.14502425[source]
I wrote this article/originally created this list, and I would like to emphasize that there is a second generation of this technology that probably uses dithering parameters or something of that sort, and that does not produce visible dots but still creates a tracking code. We don't know the details but we do know that some companies told governments that they were going to do this, and that some newer printers from companies that the government agencies said were onboard with forensic marking no longer print yellow dots.

That makes me think that it may have been a mistake to create this list in the first place, because the main practical use of the list would be to help people buy color laser printers that don't do forensic tracking, yet it's not clear that any such printers are actually commercially available.

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SomeStupidPoint ◴[] No.14502841[source]
Could you elaborate/speculate on how dithering patterns would be used?
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PatentTroll ◴[] No.14502957[source]
This isn't an answer, but I used to examine patents in this space. There are very advanced watermarking methods out there that are stable through transcoding, compression, obfuscation, etc. while being invisible to the naked eye. Really amazing stuff, wouldn't be surprised if there were lots of watermarks on media (audio, video, still image) that aren't readily apparent. One of the big use cases I remember was watermarking movies so that it would be possible to identify the time and place that a cam bootleg was recorded. That's a camcorder aimed at a movie screen and then heavily compressed and distributed over the internet, and the watermarks would still be detectable.
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1. TheHegemon ◴[] No.14503814[source]
I have implemented one of those technologies at a previous company. Their claims and what the software was actually capable of were vastly different.

I would say about 20% of the files we sent over had enough recoverable watermark to be useful.