Blu-ray Support In FFmpeg? Coming Soon, Perhaps.

[Louise]

Still optional for the studios, but most use it. AnyDVD I think is back to decrypting every Blu-Ray. Last I checked doom9 they'd figured out the easiest BD+ varietys but not the more advanced ones. So even if they did include the best of open source, there'd still be problems.

Almost, but not quite.

There is only one BD+, and is actually the opposite of what we are used to when we talk about encryption.

The key for BD+ is an algorithm. Each movie is encoded with the reverse of this algorithm with is unique for each movie.

The virtual machine that intercept this algorithm is 100% reverse engineered both by Slysoft and the open source hackers. No surprises left there.

The work right now that is left, is only to implement the remaining "traps" as they are called, when the studios decides to use them.

Traps are just another word to command or instruction. A trap could e.g. be xor.

This makes BD+ very different from AACS. BD+ is "just" a scrambling of the data, but the trick is that the key is an algorithm, not a number. hence, BD+ can not be revoked.

Once all traps are implemented, there is no point in BD+ anymore, as the open source virtual machine or AnyDVD can decode them.

Now, there are are few tricks left in BD+ such that it can verify its self using certain traps, but this can be defeated by implementing these traps so they always return false.

The idea behind BD+ was brilliant. Using a virtual machine that intercept algorithms, but once they virtual machine and the traps were understood, BD+ had no effect at all.

Everything is nicely documented how it works at

http://trac.assembla.com/bdplus/browser/trunk

check the latex doc in bdplusintro and the docs in doc.

[russell_h]

Almost, but not quite.

There is only one BD+, and is actually the opposite of what we are used to when we talk about encryption.

The key for BD+ is an algorithm. Each movie is encoded with the reverse of this algorithm with is unique for each movie.

The virtual machine that intercept this algorithm is 100% reverse engineered both by Slysoft and the open source hackers. No surprises left there.

The work right now that is left, is only to implement the remaining "traps" as they are called, when the studios decides to use them.

Traps are just another word to command or instruction. A trap could e.g. be xor.

This makes BD+ very different from AACS. BD+ is "just" a scrambling of the data, but the trick is that the key is an algorithm, not a number. hence, BD+ can not be revoked.

Once all traps are implemented, there is no point in BD+ anymore, as the open source virtual machine or AnyDVD can decode them.

Now, there are are few tricks left in BD+ such that it can verify its self using certain traps, but this can be defeated by implementing these traps so they always return false.

The idea behind BD+ was brilliant. Using a virtual machine that intercept algorithms, but once they virtual machine and the traps were understood, BD+ had no effect at all.

Everything is nicely documented how it works at

http://trac.assembla.com/bdplus/browser/trunk

check the latex doc in bdplusintro and the docs in doc.

Great post, interesting stuff.

[DMJC]

Hopefully they support drives with hacked firmware that exposes the disc keys as well. It'd be really nice if you don't have to put your keys into a text file if your firmware is patched. I'd also love to see HDDVD support. I hope they get some LG drives. The burners/players support BluRay and HDDVD. I'd like to see better support for both formats in mplayer as there's a lot of people out there who got screwed by HDDVD. It's also a much cheaper way to get HD films right now $7 australian for a hddvd movie vs $45 for bluray movie.

[RoboJ1M]

Almost, but not quite.
The work right now that is left, is only to implement the remaining "traps" as they are called, when the studios decides to use them.

Traps are just another word to command or instruction. A trap could e.g. be xor.

The traps can also be calls to BD-J libraries, the blu-ray java applet system thing. So they have to implement the a system for running BD-Js in a JVM too.

And some traps are to local hardware as well I seem to remember.

Ultimately it's just security through obscurity.

J1M.

[unix_epoch]

I certainly hope Linux gets reliable and simple BD support. As was the case with DVDs, as soon as Linux has good support, I start buying and renting. If Linux had never gained DVD playback support, my family and I would never have amassed a DVD collection worth thousands of dollars, or spent hundreds on rentals. The same applies to Blu-Ray. As soon as I can run "mplayer bd://" or "xine bd://" from my custom home theater front-end, I'll start buying and renting the discs (provided that median movie quality doesn't take a sudden, sharp, and unexpected decline).