[FFmpeg-devel] Blu Ray drive donation

[Reimar Döffinger]

On Wed, Mar 18, 2009 at 11:49:45AM -0700, Robert McNamara wrote:
> On Wed, Mar 18, 2009 at 11:29 AM, Robert Swain <robert.swain at gmail.com> wrote:
> > It seems that no one else has really stepped up and the main thing for
> > the person who receives the drive to do is to support the AACS
> > decryption, if this is acceptable to have within FFmpeg. Once decryption
> > is resolved, the rest should be 'doable' from samples.
> >
> > Does anyone else have any comments?
> 
> I have a feeling this has been mentioned in some capacity already, but
> that person should read through this thread at Doom9:
> 
> http://forum.doom9.org/showthread.php?t=140571
> 
> That was the thread wherein the open-source BD+ decryption method was
> developed, ultimately culminating in libbluray.  That project has now
> split into two seperate projects, one for handling BD+
> (http://www.assembla.com/wiki/show/bdplus)  and one for handling the
> BD-J parts (https://launchpad.net/bdj).  Apparently there is an
> interplay between the BD+ scrambling and the BD-J machine, so the BD-J
> project pertains both to menus and to decryption.
> 
> Yesterday, it was suggested that the libaacs and libbluray be merged
> under the collective name of "libbluray."  Although I use the windows
> tool for ripping my blu-ray disks, my understanding is that the AACS
> decryption under linux can either be done w/ a tool like dumpHD linked
> against a library of known MKB keys, or by owning a drive with patched
> firmware (LG appear to be popular) wherein the volume ID can be read
> without needing the key lib.
> 
> I hope this pulls together some of the information that might be
> helpful and saves someone some effort/reinventing of the wheel.

The whole BD-J, MKB etc. is outside what FFmpeg is responsible for IMO,
only the last step, decrypting given a title key, belongs in FFmpeg
proper, and probably would be doable from samples as well if someone
knows how to create the samples.
There is also something concerning AACS on the proposed GSoC projects
list, though I am unsure what the scope of that is supposed to be, with
what I think belongs in FFmpeg it should at least be AACS+CSS to be
"enough work" IMO (CSS, too, then would be from the title key on, as
libdvdcss stores in .dvdcss).
Anything beyond that would belong in the stream layer, and FFmpeg does
not implement that part even for DVDs.