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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Question: re Image Files.
Date: Fri, 31 Aug 2012 11:41:53 +0200
Organization: cbb software GmbH
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Date: 2012-08-31T11:41:53+02:00
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On Fri, 31 Aug 2012 02:25:18 -0700 (PDT), Ludovic Brenta wrote:

> Austin Obyrne wrote on comp.lang.ada:
>> That is precisely what I want to do - I have no other interest in
>> the image file apart from using the alpha + pixels dat as the
>> operands of encryption transformations.
> 
> So, you want an attacker of your encryption scheme to know that the
> cleartext is an image?

To transmit messages undetected hidden within innocently looking images?
Usual scheme is to slightly manipulate channels.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de