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Prototype Hardware DVD Decodoer for Linux-needs help
Yohahn wrote in with some news on the DVD for Linux effort. A company has developed a prototype DVD decoder board that does the decryption in hardware, versus software, meaning the that the drivers could be released under the GPL. However, because the board is only a prototype, investors need to be convinced - head over to LinuxTv.org and vote in the poll to show support for this. Please-I'd like to fully use my laptop, and this is one of those areas Linux needs assistance in.
Yah but can you get 5.1-channel surround or are you stuck with the inferior (though still better than 2-channel stereo) Dolby ProLogic (or worse)?
I believe I indirectly mentioned this already.
But again, I'm biased, having grown up where the computer was more of an entertainment center than the TV. All the TV was good for was evening news, afternoon cartoons, and hooking up the SNES/PSX to.
Watching DVDs on my 17" monitor is a little cramped, but quality is so much better than any of our TVs. I'd think that with a generation growing up on computers, it may actually be second nature to watch DVDs on a computer, especially as monitor prices are dropping.
I dunno how the market will shape, but TV viewership *seems* to be going down as more content and capability is added to computers, such as news, streaming audio and video, games, chat, etc. Either that, or TVs and computers will merge...
-AS
-AS
*Pikachu*
Even if we ignore the encryption problem, the development of an optimized software MPEG-2, Dolby Digital decoders, integration, synchronizaion, testing with the many strangely encoded streams out there, etc is an effort which should take several man-years. I would say it is outside the capabilities of the open-source community.
The encryption is available only in hardware form and a reverse-engineering resistant software module for Windows. As far as I know it has not been reverse-engineered yet, although the availability of a software implementation should make it possible, regardless of how well it is protected.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
Hewlett-Packard will be releasing a DVD ReWriter (DVD-RW) in September. It will write DVD-RWs at 1.5MB/s (maybe 1.25x DVD speed), and CD-RWs at around 8 or 12 speed. The DVD-RW discs will be 3.0GB single side, single layer, but they may only work in DVD-ROMs... I don't think they will work in DVD players. The street price should be $699, with media being $30 / blank, and the drive will be SCSI only.
This device has nothing to do with reading DVD's, its about playing back the MPEG2 data stored on them.
That's two very differnet beasts. Supporting UFS under Linux is a matter of time -- UFS isn't propriatary, its just a matter of someone doing it.
This device takes a data stream read from the video file on that UFS filesystem and decodes it into video frames.
I don't see that being useful for anything but multimedia games/applications and watching movies.
Believe me, support for DVD-R or DVD-RW is something I'd be wholeheartedly in support of. But that's not DVD-Video.
Also, MPEG2 encoding is considerably more complex than the decoding.
I guess one could make the argument that the whole point of entertainment appliances is that you slouch in a comfy chair or lay back on a couch, pop open a beer, and stare at a low-resolution display 10 feet away, and while your right hand brings the beer can up to your face, the left falls down beside the couch where it starts petting the dog. Then the cat jumps down from the back of the couch on to your stomach, and curls up. The dog gets excited, starts licking the cat, who gets very annoyed, and you end up spilling beer all over yourself and the wife shouts "What's going on in there?" as you hit the DVD pause button on your remote, and you head off to get a towel.
And at the desk, your computer is there, a high res monitor 2 or 3 feet from your face, and you gotta sit up straight. The computer is for Serious Work. No relaxing there. And if the cat jumps up on the keyboard, you throw it off. (Really, I know what I'm talking about here, since I pull about a whole cat's worth of hair out of my keyboard every year.)
But the roles are supposed to be separate, so we don't think much of it.
I dunno about all this, it sounds fishy somehow, like a weak excuse to get consumers to buy two DVD drives. Besides, computers are entertainment appliances too (proof: Id Software). I kinda like how MP3s have made it feasible to point and click to start some music, instead of spinning the CD towers to the right section, getting a plastic box, taking the CD out and putting it into the drive, and pushing a play button. Ew, the old way was so ... physical and untidy! ;-)
What I'm getting at is that this whole seperation thing is artificial. I thought human ergonomics were mostly constant. If people's computers are so clumsy that watching a movie on 'em is considered not sufficiently relaxing ("fiddling with your PC") then maybe it's the computer's fault. Have you tried putting a couch in front of your computer? Hook up an IR interface so you can use remote control? I wonder if this sheds more light on this "digital convergence" market I keep hearing about, yet didn't really understand. Maybe it's time we asked ourselves if desktop computers still deserve to exist.
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
That DVD site is back up now.. i dont know if it is just temporary so i decided to mirror it at the linuxDVD site i have been running for close to a year now. I just added a mailing list so that people can share some constructive ideas on how to solve this lack of a DVD under linux.
http://linuxdvd.corepower.com/
I think this reference design is definately a step in the good direction. I would personally rather see the specs for creative labs dxr2/3 but the biggest problem seems to be that we need specs on the c-cube chip and noone i know has ever been able to contact them. If anyone knows of a contact at C-cube, please forward their information to me.
First and foremost, DVD isn't just about movies and games anymore, just like Compact Disks aren't just about audio. It's about being able to store massive quantities of data as well. That said, even early CD-ROM drives could play audio CD's, so the ability to decode the formats mentioned on the card maker's site (MP3, MPEG, etc.) is fundamental if you want to be in the market.
The question of whether there is enough market to support the prototyping and production runs for the card is more significant. Quoting the previous post:"I think the switch to software decoding under Windows was largely because most people don't want to spend even fifty or a hundred extra bucks for a decoder card they're not going to get much use out of." This is just an opinion, mind you, but the extra money probably wasn't the issue, or SCSI would have died a horrible death a long time ago. The issue is getting the biggest "bang for the buck" and availability.
How about we do a little price shopping to compare... let's see, I can pay for
- a crappy OS from M$,
- the upgraded QT codec from Apple or an MPEG decoder board,
- a RIO or something similar for MP-3's (yes, I know there's freeware out there as well)
or... Linux + a relatively inexpensive card with Open Source drivers.... Hmmm. Proprietary vs. open. What should I do...what's that, the open option is less expensive? You get my drift.My final point is that the card mentioned is a prototype, and that once you have a successful decoder, creating the encoder is usually no big deal in comparison. So if this company succeeds, you'll have all you'd need except the DVD-burner.
A set of questions here...is there such a thing as DVD-R or DVD-RW yet? If not, is it technically possible? on the drawing boards?
I'll sit back and listen now...
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
This seems like a good idea, but how many people really watch movies on their PC? Or have their PC close enough to their TV to be able to play the movies out to the TV? It seems more of a novelty to me for anyone but space-constrained college students with expensive new computers.
:)
I doubt there'd be a big enough market to justify it. I think the switch to software decoding under Windows was largely because most people don't want to spend even fifty or a hundred extra bucks for a decoder card they're not going to get much use out of. Sure, someday DVD games or other applictations might use DVD-Video, but I doubt the game or application maker will assume hardware decoding, they'll license and bundle the software with it.
What would be more useful (and I submitted an Ask Slashdot question two weeks ago that never showed up...) would be an MPEG2 encoder and decoder card, letting Linux be able to function like those new digital "VCR"'s, either in an embedded setting or on, for example, my server that handles my voicemail and e-mail. It'd be nice to bring up one page that listed all my new e-mails, voicemails, and recorded TV shows.
The number of people who'd want one of those might not be that much higher than a decoder card by itself, but you never know.
To my knowledge, they're both encrypted. But it's not exporting the algorithms--it's the data, which there aren't any export restrictions on (well, there might be, but not because of that). And it's not that export is illegal; you just have to get a license. I would imagine Circuit City could get a license to export DIVX to Europe. They probably haven't applied because they're waiting till they get a foothold in the states (fat chance!)
There are two things going on, decoding and decryption. Looking at the linux dvd page (which has been down for about a week, from what I can tell), it seems they have support for reading the DVD file format. So you can put your 17GB DVD in there and read the data to your heart's content. They also have alpha support for decoding the data and playing a movie from it, even in hardware (which is more efficient, of course). But that doesn't mean you can play a movie. The DVD forum also put a lot of time into cryptography. Unlike copying VHS to VHS, which degrades things, copying DVD to DVD should result in a perfect copy. It's all digital, so bit-for-bit copies should be just as perfect as the original, which would make for some nasty piracy. So the DVD Forum put cryptography measures in ther. I have no idea how this works! But in order to build a DVD player, software or hardware, you have to sign an NDA with the DVD Forum saying they get your firstborn if you tell anyone about the decryption process (obviously it's not that good if they have to keep it secret; maybe they're just paranoid). Every other computer DVD solution does the decryption in software--it's just easier that way. But you can't release the source to any of this, because that would be a violation of the NDA. So these people are putting the cryptography stuff in hardware so they can still release the source to the player. So it's this or a closed-source solution for Linux DVD.
You call macrovision "rather potent"?! For one thing, Macrovision deals with copying analog. It relies on the macrovision protection in VCRs. There's an invisible (to you), varying signal that comes from any output that has macrovision (basically any pre-recorded media has this) that tells your VCR (or MPEG encoder; these also have to have Macrovision protection) that what it's seeing is just noise. So it records noise, despite the fact that you're seeing a clean picture. This, however, has been disabled on so many systems that it only stops really lazy people (what it was meant to do, I guess).
Macrovision does have some different stuff for CD-ROMs that may actually be on DVDs for all I know (if you do, please correct me; that would overshadow the ineffectiveness of the previous paragraph's system). There's more to the CD-ROM than can be copied (how, I don't know). So when you make a copy, you're really not getting everything. If they did that with DVDs, it might do something.
I've had a Creative Encore 5x DVD package with the DXR-2 decoder board for a while and it works great. Why couldn't Creative just release Linux drivers for that board? It's already in production and it's not too expensive...
LOAD "SIG",8,1
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