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by int_19h 288 days ago
Sure you can. For example, UK will jail you if you refuse to disclose a cryptographic key for something encrypted that the court wants to see, so long as the judge is convinced that you know it. I could easily see that extending to steganography: "there's no rational justification for you to have this file, and statistical analysis patterns show that it likely has a steganographic payload".
1 comments
Tade0 288 days ago
"Sir, those are just internet memes I've been sharing with a friend of mine"

The whole point of this technique is that with sufficiently low information density the data is not recoverable unless you know what you're looking for, because it's indistinguishable from noise.

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int_19h 288 days ago
> "Sir, those are just internet memes I've been sharing with a friend of mine"

"I don't believe you, so now you're going to be in the locker for contempt of court until you provide law enforcement access to this critical evidence."

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Tade0 287 days ago
"What evidence? This is normal noise associated with lossy compression. Have an expert look at it - they'll confirm what I've said."
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mbs159 287 days ago
> "Sir, those are just internet memes I've been sharing with a friend of mine"

Then it is reasonable to assume that you can just show us these internet memes?

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Tade0 287 days ago
Of course, because I can bet on the fact that no one will find anything having just those images.

Again: the signal is below the noise floor. Unless you really know what to look for, you'll just find noise. Whoever seizes these files would have to at least know the specific method used, particularly if the content is also encrypted.

Take for an example JPEG as a vessel for steganographic content: the image is divided into 8x8 pixel chunks. If you encode just one bit of entropy in each chunk, a 320x240 image will yield 1200 bits, so 150 ASCII characters. Mangle it with a one-time pad for good measure so that it actually looks like noise. How did that noise get there? Well, it's lossy compression your honor.

There are so many ways to encode that one bit in such a large piece of information that authorities are better off drugging, bribing or torturing you or whoever was the recipient of that message than trying to decode it.

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