LCE11: UMMS, an audio/video abstraction layer [LWN.net]

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 3, 2011 15:35 UTC (Thu) by rossburton (subscriber, #7254)
In reply to: LCE11: UMMS, an audio/video abstraction layer by josh
Parent article: LCE11: UMMS, an audio/video abstraction layer

You can disagree with DRM as much as you want, but when the use-cases include DVD, Blu-ray and scrambled DVB-T you can't really leave DRM out...

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LCE11: UMMS, an audio/video abstraction layer

Posted Nov 3, 2011 20:33 UTC (Thu) by josh (subscriber, #17465) [Link]

There's a difference between bypassing DRM (as in libdvdcss and the ongoing work on Blu-Ray) and accepting DRM.

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 3, 2011 21:51 UTC (Thu) by rossburton (subscriber, #7254) [Link]

Good luck selling that in a box with the Blu-ray and DVD logos on the side.

UMMS -- and by extension MeeGo TV and Tizen TV -- is designed for use in real products for use by real people. The spiritual ancestor of UMMS is being deployed in a number of set-top boxes right now.

Anyway, UMMS's DRM support mainly involves hitting the right hardware registers so that the hardware decoders kick in.

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 5, 2011 13:21 UTC (Sat) by tpm (subscriber, #56271) [Link]

Why is another abstraction framework required to accommodate DRM/Blu-ray/DVD ?

Other people seem to have no problem doing these things (DRM, DVD) with existing frameworks (in a commercial context, conforming to the various licenses etc.).

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 5, 2011 13:16 UTC (Sat) by jospoortvliet (subscriber, #33164) [Link]

From this comment I take it the other criticism (mainly 'duplicating existing tools instead of contributing to them') is valid? Or are there good technical reasons why it was decided to start all over instead of contribute to a project like Phonon or QtMultimedia?

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 5, 2011 14:14 UTC (Sat) by rossburton (subscriber, #7254) [Link]

Part of the design is DBus for license separation -- to use say Phonon with a bluray decoder you'll probably need a license exception (like GStreamer has) and I suspect Dolby approval would be impossible.

As I said earlier, the design is mostly based on real world legal and technical concerns for the target use-case (dvb, dvd, bluray, dolby) that no other projects cope with.

LCE11: UMMS, an audio/video abstraction layer

Posted Nov 6, 2011 23:36 UTC (Sun) by idupree (subscriber, #71169) [Link]

License-separation is an annoying concern from a technical perspective. But I wonder if the separate process can be useful for stability/security too. (I suspect stability: easier and security: hard, but I'm just guessing.)