[Techtalk] Copyright of Audio books

[Wim De Smet]

Hi,

On Thu, Jul 22, 2010 at 11:24 PM, Linda de Boer <ldb at swmbo.ca> wrote:
> G'day,
>
> I am trying to copyright protect some audio files which are initially
> purhcased from the author. If they are copied to another site and they try
> to publish them either as their own, or just without the author's
> permission, I would need to be able to identify them.

It seems to me they're likely to leave the author and song tags in
place. Even if they show up on places on the web with different names,
it will be very hard to actually find those. You'd actually have to
download a whole lot of files from all over the web and at least have
a look at the tags inside them.

Anyway, practical considerations aside, there's a whole area of
research into fingerprinting data sequences of various types, and
audio is no exception. I think the wikipedia article on acoustic
fingerprints will give you a good starting point
http://en.wikipedia.org/wiki/Acoustic_fingerprint

Most of the examples they list are (expensive) commercial applications
though, but you could jury rig something simpler. As the files are
likely to remain the same size, perhaps only with altered tags, you
could just strip the tags and md5sum the resulting file. People who
illegally copy these songs will probably not be making any effort to
cover their tracks either way, so I wouldn't worry too much about
putting this extra work in. Comparing tags will probably get you most
of the way.

cheers,
Wim