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I am interested, are there existing utilities/projects under way devoted to combining encryption and steganography.

I would like to
- combine two or more messages, encrypted with separate passwords, into a single output file - providing correct password will allow extracting the corresponding message only
- make sure it's not plausible to prove existence of other messages, unless I know passphrase(s) for some of those

I.e., the approach of TrueCrypt hidden volumes, somewhat expanded. Existing utilities like outguess can hide two messages in an image file - I am looking for more general approach.

Update. I disagree that the linked question has actually answers suitable for mine.

What I seek is a way to join several (two or more) messages, probably encrypted, into a data stream in a manner that cannot disclose the actual number of messages present, if any; and which can be decrypted to any of the message present, if correct passphrase is used.

None of tools known in lists such as this one can actually solve the task.

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closed as off-topic by TildalWave, Gilles, Rоry McCune, Iszi, Steve Sep 15 '14 at 16:08

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There are various projects/applications which do at least part of this. The linked question names a couple. – Rory Alsop Feb 8 '13 at 10:53
@RoryAlsop, thanks for the link. I have studied well-known steganography-related tools lists, but none can do the mentioned task, so it seems. Perhaps the optimal way is to implement such a tool. – Konstantin Boyandin Feb 10 '13 at 15:53
This does seem like it has all the necessary information covered on the site, but it combines not only steganography, but also deniable encryption. As I understand it, certain steganography solutions can provide the solution by having multiple passwords encode information without collision in the carrier, but it could also be accomplished by just about any deniable scheme. – AJ Henderson Feb 11 '13 at 13:57
To answer your update: use an archival tool to create a single file, encrypt that file, then embed it. – Jeff Ferland Feb 20 '13 at 2:17
@Jeff Ferland, I am afraid you do not understand the purpose. There should be plausible deniability. There should not be possible to prove there are more than one message in the data. And if you are forced to reveal password, you can just decrypt alternate, harmless message. – Konstantin Boyandin Feb 21 '13 at 4:08

protected by Community Sep 9 '14 at 13:30

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