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Distributed DVD Back-up Solution?
SoBeIcedT asks: "I just bought the third season of 24 [fox.com] on DVD and have begun to back it up to DVD+R using DVD-Shrink on Windows XP. Being the gadget loving guy I am, it makes sense that I would have multiple computers. The trouble is I can't make use of all of those CPU cycles and they go to waste. Is there a way (perhaps using clusterKnoppix or something of the sort) that I can easily use all of the processor power in my home to transcode the DVDs?" dvd::rip is one option that has clustering support. Are there any others?
Seems to me from the series, they could transcode a DVD in about 30ms...
You could take the easy way out. Have each computer rip/transcode a different DVD. Kick them all off at once and walk away.
"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." Col. Jeff Cooper
Dvd::rip is definitely quality software, but it doesnt (in my experience) preserve DVD menues. I also havent quite figured out how to rip the title to multiple dvds while maintaining the dvd format in dvd::rip. I end up running dvdshrink via wine, but span the title onto many dvds, nix the menues all together, and preserve the dvd video format.
Does someone have a *nix native way of doing this?
DVD::Rip looks really neat. It mentions that the heavy I/O operations are done on the system with the local disk, and that transcoding is done on the agent nodes... though I'd think there's significant I/O involved in the transcoding... has anyone got data on the point at which adding systems really stops helping unless you've got switched gigE? I would imagine that the NFS mount becomes a bottleneck at some point before you get to a dozen nodes.
500GB of disk, 5TB of transfer, $5.95/mo
Distributed DVD Back-up Solution?
It's called "BitTorrent". It even backs-up DVDs you haven't bought yet.
If you're not trying to actually compress the backup (it didn't sound like you were), might I suggest just buying Dual Layer discs and just doing a straight copy. Requires no CPU, and if you have two drives, hardly requries disk space. They are starting to come down in price, though they are significantly more than a DVD +/- R.
Of course there's also the option of just backing up to a large HD. Again, probably more expensive than blank DVDs, but lets face it, if you're buying box sets and then backing them up, money obviously isn't your biggest concern.
Um, this has nothing to do with what "format" the files are being written in - it has to do with space. A store bought DVD is dual layer, consisting of roughly 8.8 gigs of used space. Sure, they advertise 9.4 - but you can't actually use that much. So, when you buy a normal blank DVD, it's going to let you use 4.4 gigs. See a problem there? It has nothing to do with formats. Now that dual layer burners are out there, you can copy an entire movie onto once disc. However, blanks are not cost effective with dual layer yet.
I do know that in order to transcode MPEG2, you need at least a full GOP (group of pictures) in order. You obviously can't send frame 1 to cpu 1, frame 2 to cpu 2, etc due to P-frame and B-frame limitations. It seems to me that it might work in a distributed fashion if the program breaks the DVD at I-frames. Then you might have to worry about closed vs. open GOPs and all that jazz.
I'd see what the guys at Doom9 think before committing to anything.
1. You are presuming he lives in the US, is controled by US laws, and/or gives a shit about the MPAA.
Presuming that he is under US law, last I checked space shifting for your own purposes, particularly backup, was still legal. Many people have ripped their movies for some type of a media server. The origianls are still tucked away in their case, safe and sound, and I have near instant access to all my movies.
2. If the activity is actually illegal, then possibly. Trying to track down some user named SoBeIcedT likely will require more labor then it's worth when there are so many more people that would be simplier to track down (e.g. use their real names in forums). Or going after people who are actively distributing copyrighted material would be a better use of resources.
3. Grey area. Could go either way. If it was just 1 disc, then the court may lean towards giving you the benefit of the doubt. If you had 100 movies that all had their discs lost and you didn't have receipts, it may be harder to still talk your way out of it. But still, their may be other ways to document the circumstances why you don't have the originals (e.g. house fire with supporting documentation).
1. Is it unambiguisly illegal to backup a DVD in the US?
Not only is it not unambiguously illegal back up a DVD in the US, the unclarity of the unambiguousness of the activity of the unambiguous illegallity of backing up a DVD in the US makes people's head hurt when they try to fathom some wanker using double negatives when asking about the unambiguous illegallity of backing up a DVD in the US!
Is admitting wrong-doing on Slashdot admissible in court?
Probably not.
The thing is that actually making a backup is not illegal, in any way, shape, or form. It's not even illegal to *own* something that will perform a backup. What's illegal (more or less) is importing or selling a device (whether hardware or software) that will make a backup, or (as interpreted by Judge Kaplan) telling someone where to find a device that will make a backup.
Computers count in Binary, which means that anything a power of 2 is easier to work with. So a kilobyte is 1024 (2^10) rather than 1000 bytes. Back in the days of CD-Rs, a 700mb cd actually was 700*1024*1024 bytes large, more of less. (I remember mine are usually 702 or 703mb)
When DVDs came along, they realized that they could get more marketing power and count a kilobyte as 1000 bytes, just like hard drive manufacturers do. So your "9.4gb" dual layer DVD has 9,400,000,000 bytes of data on it, which works out to 8964mb, or 8.75gb.
Of course, this can't compare to the 200 gig hard drive I bought many moons ago, that only formatted to 186 gigs :/
I'm backing up my entire DVD collection onto hard drives. I have a PC attached via DVI to my 50" TV and we generally watch the movies off of the drive, rather than the disk. So this is a question I've put some thought into.
My solution is not to bother with distributed transcoding, because although dvd::rip does it nicely, I just don't find it worth the effort. My media PC runs MythTV and the MythDVD ripper/transcoder does a nice job of queuing up the work. I throw a DVD in, pick the correct title, choose my quality settings (either Perfect, which retains the full DVD stream, not transcoding at all, or Excellent, which transcodes with XVid to files in the range of 1-2GiB, with generally good quality) and hit "go". 10-15 minutes later, the DVD ripping stage is done, and I throw another DVD in and start ripping it. Meanwhile, transcode has started working on the first transcode job. When the second DVD rip is done, the transcoding job is added to the queue, to be started when the first transcode finishes.
Throughout the course of the day, I throw another DVD in the tray whenever I happen to think of it... usually every hour or so. Meanwhile, the transcoding jobs just queue up. The one machine does them all, in sequence. It takes 3-4 hours per transcoding job (on a Sempron 2800+ downclocked to run as a 2400+), so the box just keeps chugging away, all day and all night. I'm lazy enough about starting new jobs that it usually manages to almost catch up during the night. Right now I have about five jobs in the queue and I'm about to put another disk in.
I have other boxes that I could use to distribute the load, but I find that I actually get more transcoding done this way because it takes less of my attention.
Of course, I wouldn't mind at all if someone hacked MythDVD to distribute the work... then I could queue *and* distribute.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
DVD.box.sk has an article comparing seven different DVD reencoding applications. DVD Shrink ranked low, while InterVideo DVD Copy came out on top.