[LAU] Looking for Audio Watermarking Advice & Tools

[Pedro Lopez-Cabanillas]

On Sunday 23 October 2011, Kevin Cosgrove wrote:
> 
> On 23 October 2011 at 17:38, Fons Adriaensen <fons at linuxaudio.org> wrote:
> 
> > On Sun, Oct 23, 2011 at 08:13:24AM -0700, Kevin Cosgrove wrote:
> >  
> > > The subject line says it all.  I'm looking for a Linux solution to 
> > > watermarking audio.  Thanks...
> > 
> > I've never seen any. The amount of work to develop such a thing
> > would depend on your exact requirements. Important parameters
> > are:
> 
> I never thought much about requirements, as I wasn't thinking of 
> creating one.
> 
> > * Which operations should leave the watermark intact. If this
> >   includes lossy encoding/decoding things get more difficult.
> 
> Maybe version 0.5 would work with lossless and version 2.X would
> work with lossy?
> 
> > * The minium duration of a fragment that allows the mark to be
> >   detected.
> 
> However long is easiest I suppose.  1 sec?  10 sec?  Repeated in 
> spots through the file X times, where 1 < X < (length in minutes)?
> 
> > * How strong the 'provability' should be.
> 
> Maybe version 0.5 is 10% chance of proving, and version 2.X would be 
> better?
> 
> > * Operational requirements. For example, should it be possible
> >   to verify the mark without having the information necessary
> >   to remove it ?
> 
> Some operations would be:
> 
>   - Mark
>   - Un-mark
>   - Re-mark
>   - Remove
>   - Verify signature
>   - Verify content
> 
> In a later version maybe the tool could be able to use some of the 
> above tools, in cooperation with other sound file tools, to preserve 
> a watermark across sound file format conversions, between lossless 
> forms and crossing between lossy/lossless domains.
> 
> For version 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?

This reminds me when the SDMI (Secure Digital Music Initiative) [1] tried to 
use audio watermarks among other technologies trying to stop piracy. AFAIK, 
the initiative was not a success [2].

Regards,
Pedro

[1]
http://en.wikipedia.org/wiki/Secure_Digital_Music_Initiative
[2]
http://cryptome.org/sdmi-attack.htm