I've just come across Keith McDuffee's article on Steganography with Flickr (via the Unofficial Apple Weblog) which looks interesting since, not only is your distribution channel is in plain sight and a broadcast medium at that, your content is disguised amongst a good deal of extraneous noise. Of course now that Flickr knows people are thinking about this, JPEG's which are "just a bit on the large side" for their actual pixel count might start getting flagged automatically by their software. Which isn't necessarily a good thing...
Steganography does not create slack areas within the media file, instead the media bit-stream iself is modified to carry the embedded message. This is unlike attaching the message-file to the tail of the media file. So the size of the host file stays the same, and the alteration can only be detected by analysing the host file.
ReplyDeleteYes agreed, but I was under the impression that depending on the compression method used adding non-randomised data would increase the overall data file size?
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