From: tcmay@got.net (Timothy C. May)
Date: Sun, 10 Mar 1996 04:30:52 +0800
To: cypherpunks@toad.com
Subject: Re: art-stego
Message-ID: <ad60a0450702100410e8@[205.199.118.202]>
MIME-Version: 1.0
Content-Type: text/plain



This is a very good idea. I wish I'd thought of it.

Just bear in mind that this form of steganography is getting further away
from conventional hiding, and into "pure plausible deniability." In fact,
one need not even make a serious attempt to hide the encrypted bits: just
call the encrypted file "art" and be done with it! (I'm not saying stego is
worthless, just that there's a slippery slope one can get on, with one
extreme being this fiction that "this is not an encrypted file, this is
_art_!")

At 7:18 PM 3/4/96, Jim Miller wrote:
>The recent discussion "Chaff in the Channel" got me thinking about an
>alternative to hiding random bit streams in picture files.  The goal of
>steganography, as I see it, is to provide plausible deniability.  The

Yes, all those critics who point out that steganography (not to mention
stenography) is an example of the rightly-maligned "security through
obscurity" are missing this point, that steganography arises in situations
where the mere act of communicating is itself actionable. (Get caught in
Berlin during the war with invisible ink or microdots and get hanged the
next morning, whether or not the SS can read the traffic.)

>problem with hiding bit streams is that you can never be sure if the
>opponent has developed an analysis technique to prove a particular file
>contains a suspicious bit pattern.

Yes, this is why I suggested (some years back, originally) that noise be
deliberately added to even images not intended for communication, as
"chaff" to confuse traffic analysts.

Your approach is a better one, as the "art stego" market, while small,
could be self-sustaining.


>The alternative to hiding bit streams is to not hide them.  Use them to
>generate pretty pictures.  For example, modify a fractal image generator
>to accept a bit stream as input.  Use the bit settings to influence the
>values used to iterate the fractal function.  You don't have to use
>fractals, any function that produces pretty pictures would probably work
>as long as there was a way to extract the bit stream from the final
>picture.  Brute force would probably work fast enough for humans.
>
>One possibility is a screen saver that produces an "infinite" variety of
>pretty pictures by generating a pseudo-random bit stream and using it to
>help generate the next background picture.  Occasionally, the picture
>might be so cool you will want to send it your friends or post it on the
>Net or just keep it around to look at.
>
>The goal is to create an innocent reason for passing around unique images
>that contain random bit streams so we don't have to worry if somebody
>finds the bit stream.  If you live in a country that doesn't outlaw
>abstract art you have plausible deniability.

Now it's just up to someone to implement this. I don't expect this to be a
huge market--remember what's happened to all those Mandelbrot images that
were once the rage--but there's a chance it will get established as one of
those "cool" apps that are tres trendy for a while.

I still would expect that when the Hamas leaders in Gaza are picked up for
questioning and "ArtStego" is found on their systems, along with various
"abstract artworks" on their disk drives, that Mossad will not be fooled.

--Tim May

Boycott "Big Brother Inside" software!
We got computers, we're tapping phone lines, we know that that ain't allowed.
---------:---------:---------:---------:---------:---------:---------:----
Timothy C. May              | Crypto Anarchy: encryption, digital money,
tcmay@got.net  408-728-0152 | anonymous networks, digital pseudonyms, zero
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