[MPlayer-dev-eng] what happened to the blu-ray support

[Alexander Roalter]

On 28.06.2010 12:43, Dâniel Fraga wrote:
> On Sat, 26 Jun 2010 23:56:49 +0200
> Alexander Roalter <alex at roalter.it> wrote:
> 
>> Ages ago (it seems) there was a patch by Jonathan Nell that enabled
>> basic blu-ray playback from the medium with a known VUK., but I just
>> wanted to know the status. I was able to plug in the patch in the first
>> place with almost no changes to the current svn, and was able to play my
>> 2001 space odyssey BD with it (since the key is known).
> 
> 	I have the same oppinion as before: while developers struggle
> to manage the key/encryption issue, MPlayer is stalled. It could be
> much better to focus on a decrypted disc supporting:
> 
> 1) PGS subtitles (a long requested feature nobody cares to implement)
> 
> 2) menus
> 
> 3) playlist
> 
> 4) extras
> 
> 	etc, while developers try to break the encryption (which, if
> you think about BD+, isn't trivial so you will keep discussing it
> forever until blu-ray is completely obsolete).
> 
> 	So, please focus on what is relevant: the features of the
> blu-ray. Users can just decrypt the blu-ray by other means by
> themselves, even if they use DumpHD or DVDFab (which can be run through
> Wine) or even AnyDVD HD (through Virtualbox etc).
> 
> 	After you implement all blu-ray features, then you can discuss
> about encryption which will take much longer and it's much much harder
> than to implement menu/playlist support, for example.
> 
> 	So focus on what is *easier* first... It's non sense to focus
> on the hardest part and left the easier on the TODO list...
Apart from the subtitles, which would be nice, menus, playlist and
extras are very very low on my personal must-have list.

If all goes as expected, I can playback BD+-less discs with the key from
the database directly, by simply performing normal decoding.

Here is where the hard part would come in: in the bd_read-function, the
patched (via BD+) stream should be delivered, i.e. if a sector number is
known to have been modified by BD+, it has to be replaced at this point.
This -- to my knowledge -- has not yet anything to do with breaking
encryption.

The last stage would then be getting the VUKs from the disc somehow, and
here is where the encryption knowledge is called for. But having a
player for the stages before this would not hurt either, even if it is
without subtitles, menus or whatever. I remember watching the godfather
way back without the in-place subtitles on the italian scenes... lucky
for me I know italian, so I didn't need (and miss) them. Same situation
today: watching blu-ray, but without subtitles. at least I don't have to
dump 30-40GB of data on the hard disk before watching the movie, be it
with. The just-in-time-decryption while reading from optical disc and
immediate playback should be the norm, -dumpstream could offer the
possibility to get the unencrypted stream, but noone should be forced to
playback the stream from harddisk.

-- 
cheers,
Alex