At 4:01 PM -0400 9/18/03, [EMAIL PROTECTED] wrote:
On Thu, 18 Sep 2003, edo wrote:

 Maybe it works as a very, very weak form of encryption, one which can
 be decrypted at a glance by humans but would evade the most simplistic
 computer recognition systems.  But stego it ain't.


Steganography is in the eye of the beholder.

Very nice line.


I have to agree. There are always two channels in steganography and its cousin watermarking. You want to make changes in one channel so the other channel isn't affected. In this case, a munged word doesn't affect the human reader but it can carry log_2(n!) bits where n=count of non-duplicate letters - 2. So we have two channels.

Now, I will admit that a large number of munged words will trigger something in the human, but it's entirely possible that three or four munged words on a page WON'T EVEN BE NOTICED. Believe me. I've proof read books a number of times and it's surprising how much gets through even the best copy editors.

Three or four words per page is also enough to insert more than a few bits of watermarking. A seven letter word can carry almost seven bits. So let's call it 6 bits. If you change four seven letter words on a page, you've 24 bits. Not bad.



-Peter


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