Re: Digital Watermarking query

Dutra de Lacerda (dulac@ip.pt)
Mon, 06 Apr 1998 12:31:48 +0100

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At 11:49 pm -0700 4/2/98, Marty Levy wrote:
>Q. If not, is there any watermarking method likely to allow me to
>keep traceability?

Maybe...
But each message needs to be differentiated by the Mailer Program.
This means your Watermark SHOULD be also a Mailer.

How?!?
Simply modificate the message for each destination, assuming it is
a person only, with the addition of spaces in selected places.

What?!?
Give each person a identifier.
Remove every double spaces with only one until got single spacing.
Code the identifier as one space=0 and two spaces=1.

You got your watermarking... Naive but effective unless known.

Regards,
Dutra de Lacerda.

P.S. - I had the same problem...

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