How to keep invisible information in an image?

Question

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The difficulty is that the picture can be printed, cropped, scanned and printed again. How can you identify such a picture and store some information from the tags in it?
For example, we produce a lot of pictures and can identify them by some ID of 16 characters maximum. The customer prints out the pictures and sends them with corrections, sometimes the pictures arrive with a six-month delay. Pictures have no tags or original names, how to identify such pictures? Is it possible to embed an identifier in an image so that it is not visible and is resistant to random noise?

Answer 1

Add a QR code to the picture with the file name (or other information) and tell the customer that you really need this code to identify and speed up work.

Answer 2

This is an absolutely sabotage workflow, which is doomed to unnecessary fuss.
In general, this problem has no solution.
There is a solution to the case when the pictures are not printed, but edited only in electronic form (re-saving, re-compressing, changing formats are allowed). Also, this will only work for photographic images, not schematics. Principle - Fourier expansion, modification of high frequencies, inverse expansion.