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Comment by StavrosK | Hacker News Reader

Wouldn't this be completely defeated by just simply encrypting the data beforehand?

The title specifies that it is talking about naive steganography. So, yes, your less-naive implementation would thwart this analysis :)

Yes.

And, in general, people don't hide the image of some text inside another image. They hide the text. And that isn't so linear (blocks of 0s or 1s)

But we agree that the bar for something non-naive is extremely high if you want to defeat the well-funded adversaries and whatever they come up with in the next few decades (future algorithms will be applied to today's images). I'm sure they have nice libraries of the artifacts most cameras and compression algorithms should leave in any image and if it isn't there, well, let's look for some steganography?

I'm pretty sure you are overestimating the capabilities of government agencies. At least I hope so.

Ha! In general I assume that the NSA is ahead in many areas that remain classified.

I liked the idea... yes, it's possible to have a catalog of expected artifacts in JPEG images, in general. And the other way it would also make a good place to hide: changing artifacts from one camera to another, for example.

But the text would still be super-easy to find because it would create a bias that's not normally present in the least significant bits. Also, if not encrypted, the bias would conform to the letter frequency of one of the natural languages.

Think about captcha and why you might use an image of a cyphertext to defeat automated tools.

Could be combined with barcodes as well.

Yeah, normally it would be encrypted text. Text is not too large. Encrypted so "random".

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