I know Calibre can remove DRM, but it seems that Calibre does not remove things like watermarks, references to the buyer by name, etc. Now maybe I can try to find those manually, but that is an error prone process. Plus, what if they embed a unique digital signature that ties back to me? I understand that this is a very uncommon practice, but I do not want to find myself in a bad place.
I suppose the only way to remove a digital signature of any sort is to buy two of the same e-book by different people, diff them, and remove anything that differentiates them.
Is there any tool that does this or automates the process? am I being too paranoid, and this is not a real threat?
Even with OCR, couldn't your copy at least in theory be laced with strategically placed minor word changes? Say throughout the book you pick 30 spots to change a word without changing the meaning of the text, or you introduce a typo. If every copy gets a different set of those that would be a unique identifier.
I think I have heard that being done with imperceptable changes in films sent for showings in theaters.
@matcha_addict@lemy.lol In this situation, I'd advise acquiring a copy from an alternative source, then just compare the texts of the two.
In practicality though, if you're already going the OCR route then just utility knife cut the pages from a real book and feed them into a feeder scanner. All they get to know is that some asshole cyberpunk script kiddie jacked your book while you were waiting at a bus stop.