New IBM Linux Notebook Includes DVD Player

An anonymous reader noted that there's a story on Newsforge about IBM's new ThinkPad. This story says it's the "first commercially available Linux computer with the ability to play back DVDs." The 900MHz Linux T22 will come with a commercial Linux DVD player. Meanwhile Xine, Xmovie, and OMS race to be the first one to support all the features (I need subtitles for anime darnit!) in an open source project, but since CSS plugins float around the net for each of them, actually playing DVDs is something they can do pretty well depending on your hardware. Most interesting about this LinDVD included with the ThinkPad is the implementation of one feature no user needs: Macrovision... done as a kernel module? Hrm.

xine does subtitles (almost)

Xine lets you display overlays (subtitles) but it doesn't do a very good job of it yet. Unfortunatly most Anime houses use the overlay feature in ways it was never ment to be used in valient efforts to get a third color on the screen, which confuses the heck out of many software DVD players.

Also, I've never been able to get xines .ifo support to work correctly, so on some DVDs you'll only get 1/2 or less of the subtitles.

Still, the feature is there, and possibly even useful in some circumstances.

Down that path lies madness. On the other hand, the road to hell is paved with melting snowballs.

Macrovision module security

Out of purely academic interest, how much care has been taken to ensure the integrity of the Macrovision module? Anyone know whether it is possible to recompile the kernel in question and get the binary driver to work with it, optionally hacking the driver? Does the Macrovision module have any sort of cryptographic integrity checking mechanism? How hard would it be for a rogue user to (a) replace it with a dummy module, or (b) interpose a "man in the middle" module which loads it and tricks it into disabling Macrovision?

The intersection between "trusted client" security (as demanded by the MPAA/RIAA) and open source OSes should be interesting to watch.

Re:Does this remove the justification for DECSS?

The point of DeCSS is to have the flexibility to watch the videos you *buy* in whatever manner you want. If I want to be able to convert the MPEG2 video to MPEG1 to watch on my portable VCD player, what is the problem? I do not want to pirate the movies I buy.

The main reason CSS was put onto DVDs is to stop people watching movies bought in other countries, so the movie companies could actually control prices for these movies.

CSS does not hinder pirating....it hinders consumers' rights to watch the movies on the player of their choice.

Re:Macrovision@Everything2

Macrovision works by messing with the time base on the outputted video signal. Normal NTSC video consists of 60 fields/second (well, 59.xxxxx) regularly spaced through that interval. Macrovision increases the timing between the fields slightly. This doesn't affect viewing, but when you record, the tightly-synced 60 fields are go in and out of phase (anyone remember "beats" from your high school physics class on sound waves?).

To overcome macrovision "protection," you need some form of a time base corrector. Most TBCs sell for a couple grand -- they're used by video editors for making sure the source and record decks are synced perfectly. Some consumer VCRs, however, do time base correcting internally (I have a Sharp VCR that I use between my DVD player (with composite out) and my TV (with coax in)). It overcomes macrovision, and could probably be used to tape macrovision-enabled video sources, but I haven't tried.

-Chris
...More Powerful than Otto Preminger...

Re:macrovision ...NO-COPIES explained

That message usually means you have a `reviewer' copy of the tape or dvd. The studios send out dumptruck loads of tapes to newpapers, tv news shows, and basically any creature that might generate some press for them. In order to keep these from dilluting sales they mark them.

Re:Does this remove the justification for DECSS?

Nope. the justification is still there.

A $3500 "off-the-shelf" DVD-capable laptop is small comfort for those of us that purchased DVD drives and decoders long ago, and will probably never see drivers, binary or otherwise, released by the companies we purchased the equipment from.

Quite frankly, the DVD business is the only reason I still have Windows installed, and I keep watching the em8300 (DXR3/Hollywood+ card) driver releases, as well as Xine and OMS developments, for the day I can get that crud off my drive and I can happily watch DVDs on the platform of my choice.

Another linux DVD program

They forgot to mention another linux dvd program
called VideoLAN (http://www.videolan.org [videolan.org])
works on my system, does css (i think),
and has subtitles. get a pretty decent framerate too.

I saw it annouced over on freshmeat,
but never see anything mentioned about it.
just though I'd post a link.

-Slackergod

macrovision

Is this why the DVD divx rip I watched the other night had "if you bought or rented this movie please call 1-888-NO-COPIES" or whatever on the bottom of it? I tell ya, if it was there the whole time you wouldn't care, but it's because they do a smooth fade in of it that it's really distracting (like win2000 popup menus, *shudder*) after about the 15th time I was ready to call the number and tell them to piss off.

WinDVD

I've never used LinDVD, but I use WinDVD, which is produced by the same company. I've been very impressed with its performance, so much in fact that I ditched by RealMagic MPEG decoder card because WinDVD produces much better results, assuming that your CPU is fast enough. I was plagued with visual "noise" and shaky video with the RealMagic, which are not present in WinDVD. So if LinDVD is based on the same codebase, I expect that the DVD playback quality should be pretty good.

IIRC WinDVD is only $30, so LinDVD should be similar in price. I was unaware that the product had even gone gold... perhaps I should pick up a copy for my Debian laptop.

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GPL?

So what about our favorite "viral license", the GPL? If this is a loadable kernel module ONLY, they can get around it. But if they link with the kernel, they have to release source code, which I'm sure they do NOT want to do.

On the other hand, if it's just a LKM, then it's in a nice self-contained file where it's easier to disassemble and patch, or even replace with code that does nothing.

Wrong

Macrovision doesn't mess with timing at all. It puts a spike signal into the vertical retrace. This messes with signal levels in such a way that the cheap AGC (automatic gain control) circuits in most VHS video recorders freak out and mess with the brightness of the picture. There's also a Macrovision II (aka Colorstripe) which messes with the colorburst signal on a couple of lines of the picture, but this can't even be recorded onto master VHS tapes, and is only generated by DVD players. Either way, since this is patented by Macrovision, studios must pay MV whenever they enable either of these features on a DVD disc.

Betamax video recorders were not vulnerable to this signal and would supposedly copy it perfectly. Ditto for Go Video VHS recorders, although I think they were eventually forced to put the crappy AGC circuit into their stuff a couple of years back.

Time Base Correctors fix the problem because the nasty signals are in the sync areas of the screen, which they throw out and replace with clean signals. But a true TBC (which makes sure that entire scanlines come through with the right timing, something that videotape is not accurate at) is overkill for Macrovision.

Don't forget VideoLAN

It's a nice DVD player that supports on the fly subtitles and language selection, that directly reads your DVD without having to mount it first, reads encrypted DVD (without using DeCSS), has multiple front-ends for different platforms.

I don't know if it's "the best one" or not, but it's the only one I managed to compile AND make work, so I thought I'd mention it.

More info on their web site [videolan.org].
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Ash nazg durbatulûk, ash nazg gimbatul,