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A comment on List of Printers Which Do or Do Not Display Tracking Dots. Parent comment

Re:List of Printers Which Do or Do Not Display Tracking Dots by cm2187 on Wednesday June 07, 2017 @07:57AM (#14505503)
But that would be possible for a photo. But typically you would print some text. I wouldn't expect any dithering / half-tone in a text document.
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Re:List of Printers Which Do or Do Not Display Tracking Dots by dspillett on Wednesday June 07, 2017 @11:01AM (#14506989)
"Methods of making practically invisible changes to pure text are available too" as mentioned in the post referred to. If using printer fonts rather than explicit vectors then it is possible to hide enough data in small "mistakes" invisible to the naked eye.

I'm not sure what would be possible for pure vector graphics.

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Re:List of Printers Which Do or Do Not Display Tracking Dots by CapacitorSet on Wednesday June 07, 2017 @02:55PM (#14508931)
For vector graphics, I suppose you could encode information in the least-significant bits (with redundancy, error correction and whatnot) if the printer can guarantee sufficiently high precision (not accuracy, mind you: https://www.tutelman.com/golf/measure/precision.php)
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