Re: Watermarking [Re: Campaign for position of chair and mandate to close this community group]

On Fri, Jan 10, 2014 at 10:06:50AM -0800, Mark Watson wrote:
>    On Fri, Jan 10, 2014 at 9:06 AM, Olivier Thereaux
>    <olivier.thereaux@bbc.co.uk> wrote:
> 
>      David, thanks for starting this discussion.
> 
>      On 10 Jan 2014, at 16:56, David Singer <singer@apple.com> wrote:
>      >
>      > I am only aware of two uses of watermarking in copy protection:
>      >
>      > 1) Define the system such that all players must detect watermarks and
>      refuse to play unlicensed content. [snip] So, this approach neither
>      meets your goals nor works well.
>      [*]
>      > 2) Use watermarks for forensics. Every copy delivered is watermarked
>      in some way.
> 
>      Generally used for online music sales these days if I*m not mistaken. I
>      also recall seeing it recommended by professional photographers
>      associations (such as the ASMP).
> 
>      I seem to remember earlier discussion in here about this type of
>      watermarking, and there was significant push back on the idea (from
>      MarkW?) based on the assumption that such mechanism would defeat any
>      attempt at caching, and thus render an already hairy bandwidth issue
>      even hairier.
> 
>    What I said back then was two things:
>    - in practice, because of the economics of content distribution, per-user
>    or per-device forensic watermarking would probably be done at the client
>    device and this approach does not avoid the need for non-user-modifiable
>    client components
 
I wonder if that's just a temporary constraint in a narrow set of
markets. For instance, Apple uses (or used) simple email identification
tagging on their MP3 downloads (does that still exist, David?), but they
have the benefit of controlling their entire delivery system. I can
imagine that third-party CDN services would be hard-put to place unique
identifiers on current content and perhaps would have no current
economic reason for doing so, but what technically is standing in their
way?

>    - using forensic watermarking to identify individuals brings with it a
>    risk of mis-identification as a result of stolen credentials, identifiers
>    that persist when a device is sold etc. The consequences of such
>    mis-identification ought to be carefully considered. 
 
This is true, but there's definitely been some thought put into this. I
think one of the elements to raise here is the dangers of any such
identifiers being used to prevent the transit of material; you don't
want to create fingerprints, and then find yourself mandated to monitor
those fingerprints deep in the network. (This is David's first category
of watermarking and the only one I've encountered when dealing with
video works).

d.

Received on Monday, 13 January 2014 23:49:59 UTC