Two things I didn't know about Blu-Ray

Thing one is that Neil Young considers Blu-Ray_TM to have provided the long-sought suitable medium for his archive project. Me and Neil, we go way back. Well, he wouldn't know me from Adam, but I spent many a college (and post-college) hour listening to his stuff. Even saw him live once. Good times. Good times.

Thing two, from the same article, and since I'm a stick-in-the-mud this is probably just news to me and not to the rest of the world, is the "live" aspect. In a pretty slick move, Sun managed to make Java support part of the standard for Blu-Ray players. The result is called BD-J. This is good for Sun, obviously, but also good for anyone who likes "interactive" content.

DVDs have a fairly crude mechanism for letting you navigate menus and play simple games (which basically boil down to navigating cleverly disguised menus). With Blu-Ray, there's a real programming environment under the hood. Expect this to go mostly unused, but also expect a few people to do seriously cool things with it. Neil and the gang certainly look intent to get some good out of it.

Further, a "BD-live" player is required to include (at least) a gigabyte of local storage, which the BD-J platform is able to divvy up securely so that each disc has its own private piece of storage associated with it. This means that an appropriately authored disc can effectively be updated, even if the disc itself is read-only. A writable disc can be updated after the fact, which is the way to go if you want more than a parcel of the player's gigabyte to work with.

OK, so what's so special about a disc that can be updated? If I download something to my hard drive, then download an update, I've now got an updated version because, well, that's what hard drives do. There are a couple of interesting wrinkles in the Blu-Ray case:

• You can either update the disc, in which case the update travels with the disc, or (to a lesser extent) update the player, in which case the update stays with the player.
• Assuming the various DRM measures Blu-Ray uses are effective, the updated content can't be copied anywhere else. Or at least, it's no more copyable than the original content.

The second item leads to a weak form of Vixie's dystopia: It would appear quite possible for a BD-J application to let you add your own content to a disc, say notes on where you were when you first heard a particular song, or comments on the action in a movie. If all the machinery works as advertised, your only access to that content will be through a Blu-Ray player. It's your content, but you don't quite own it the way you normally would.

There ought to be ways around this, for example by making your own copy of any changes you're about to make before actually making them, but it's still an interesting point.