IDs in color copies and prints

[rowrrbazzle]

I’ve just read the latest post on on the comp.risks ng, and it had a fascinating item. The item is also available here:
http://catless.ncl.ac.uk/Risks/20.68.html#subj5

The item reads in part:

…xerographic color copiers/printers include “steganographically” encoded IDs. Essentially, these IDs are encoded repeatedly as part of the background “noise” in images, and cannot be decoded without knowledge of the proprietary algorithms involved.

Any comments? And are you looking over your shoulder for the hidden telescreens, like me?

z

“Who controls the past, controls the present. Who controls the present, controls the future.”

Orwell, 1984