NODE 99d8da5bRe: Canon copiers
peb@PROCASE.COM (Paul Baclace)Thu, 21 Oct 93 16:28:05 PDT
> response was that "the machine would be virtually destroyed."
> Anyone want to test this for us?
Stand back, the thermite grenade in the black box could be hot.
;^)
I'd like to know how they put the serial number into the copy.
Paul E. Baclace
peb@procase.com
NODE 443a03dbRe: Canon copiers
"Robert J. Woodhead" <trebor@foretune.co.jp>Thu, 21 Oct 93 18:58:04 PDT
Paul writes:
>I'd like to know how they put the serial number into the copy.
Most likely by modulating the Least Significant Bit of the color
intensity in some (or all) color-filled areas of the image. A
set of sync-bits, serial number, and some more sync bits. Repeat
every line, shifted by 1 bit, and you'll get a pattern that is
hard to differentiate from the background unless you _know_
what to look for.
I wouldn't be surprised if there isn't a time and date stamp
as well, plus batch # info.