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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 should ask the MPAA. I'm sure they would like to help you with this.
DVD and have begun to back it up to DVD+R using DVD-Shrink
Why do people accept this solution? Why is it necessary to use DVD shrink and discard large quantities of data in order to fit a DVD onto another DVD? Am I the only one that sees this scheme as ludicrous?
The main question is, why can't DVD writers write in the DVD format rather than +-RRW? I won't accept the cost argument. If it really was that much more expensive to write in native DVD format, Blockbuster would be stocking DVD+-R instead of DVD's. WTF?
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
Bet you didn't know that Dell's desktop machines were 32 way systems.
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.
Is this guy's admission of backing up a DVD enough evidence for the MPAA to put him away for life??
Here are the pertinent questions:
1. Is it unambiguisly illegal to backup a DVD in the US?
2. Is admitting wrong-doing on Slashdot admissible in court?
3. If I were to backup a DVD I owned and then lose the original and the recipt, then there would be no evidence that it really is a backup. Am I still "allowed" to have the backup?
Discuss, discuss
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.
I'd like to be able to set up a CD filesystem where the journal is continuously written until the CD is full. The hard drive can be used to buffer the journal until a full block can be written to the CD.
When the CD is full the journal can be compressed to create a new filesystem on a new CD.
If we do this then we never have to do backups again.
Some problems lend themselves to being parallelized, and some don't. SETI at home is a great example of those which to parallelize.
Is video encoding the kind of task that even can benefit from this? Does the encoding of each segment happen independant of what happened before?
It sounds to me like this mightn't be the kind of problem to benefit from clusters.
Cheers
Lost at C:>. Found at C.
Good suggestion to check out Doom9, but the problem is that no one there may really care at all about this question. There is no doubt that there are some really bright people there who really understand video, but I remember a couple of years ago when everyone in one of the forums kept congratulating themselves for being special because they got to play with a beta version of an MPEG-2 transcoder that wasn't released to the general public. About 50 guys kept posting about how great it was, but no one would say how they got it. This went on for about 6 months before the author finally released the program. I call this the "Aren't we cool?" situation. Another problem at Doom9 is that sometimes no really cares about your problem and they won't attempt to answer it. So the guy who wondered about this can always ask, but I wouldn't hold my breath that he'll get a reply.
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.
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Did you just admit to breaking the law on Slashdot?
With hard drives so cheap, I use them to backup my DVD's instead.
My setup is Debian Linux with Kaffeine media player. I start playing the regular DVD in the drive until the movie starts (where the encryption is). Then I shutdown Kaffeine and type "dd if=/dev/cdrom of=name_of_dvd.iso". Kaffeine can play the image file without having to mount it.
Works really well, and is an _exact_ image of the DVD with menues, special features...everything.
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Why bother to backup movies/tv shows of discs you purchased?
Say you own 1,000 dvds and it costs 50cents a blank to backup. You're still wasting $500 to backup each disc not to mention the HUGE amount of wasted time. In the off chance you actually damage a disc beyond the ability to watch you can rebuy the movie.
If it's a TV series disc and you don't want to spend $80-100 for a complete copy of the season you already own to replace 1 defective disc then rent it and make a copy or bitch to the studio for a replacement. I'm sure for a small fee (if not free) and sending the original now defective disc to them they would gladly send a replacement.
DVD.box.sk has an article comparing seven different DVD reencoding applications. DVD Shrink ranked low, while InterVideo DVD Copy came out on top.
It's not losing 14 gigs to the filesystem, it's losing 14 gigs due to the difference between 200 billion bytes and 200 gigabytes.
Yes it is losing 14 GB or 13 GiB to the file system. Many file systems will use larger clusters for larger partitions, and when a 1 KB file fills a 4 KB cluster, you're wasting 3 KB of space. (Not all file systems have the "tail reuse" feature to pack multiple files into one cluster the way, say, ReiserFS does.) Multiply this by the hundreds of files in a typical large program's source tree, and losing an average of 2 KB per file becomes significant.
Why not just run one disc on each machine?
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Come on. Stop scrooging and get a HP Storageworks Optical Jukebox. You know you want to... :D
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All Transcoders suck. While DVDShrink with Deep Analysis is pretty good, go with a full re-encoding solution.
DVD Rebuilder (mentioned by someone else) is really good, simple, and uses CCE, the best MPEG-2 encoder (requires purchase of CCE, which I think the basic version is something like $20).
The best part? Includes a mode for render farms, so you can use all those CPU cycles.