Kevin,

Would something like this suffice or at least lead you in the direction you were headed?
http://www.codeproject.com/KB/security/steganodotnet8.aspx

-M

Date: Sun, 23 Oct 2011 08:13:24 -0700
From: Kevin Cosgrove <kevinc@cosgroves.us>
Subject: [LAU] Looking for Audio Watermarking Advice & Tools
To: linux-audio-user@lists.linuxaudio.org
Message-ID: <20111023151325.350C7BE006@joseph.cosgroves.us>
Content-Type: text/plain; charset=us-ascii


The subject line says it all.  I'm looking for a Linux solution to
watermarking audio.  Thanks....

--
Kevinersion 0.01 even just being able to attach an md5 sum of an 
audio file along with a gpg signature would be cool.

I use a subset of GNUPG's capability.  Maybe you can see that in
my above requirements?  ;-)

Is that a useful start on a start?

Thanks....

--
Kevin