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Best Way To Store Digital Video For 20 Years?
An anonymous reader writes "My kid is now 1 year old and I already have 100G of digital video (stored on DVDs, DVD quality) and photos. How should I store it so that it's still readable 10 to 20 years from now? Will DVDs stil be around, and readable, 10 years from now? Should I plan for technology changes every 5 to 10 years (DVD->Blue-ray->whatever)? Is optical storage better, or should I try to use hard drives (making technology changes automatic)? And, if the answer is optical, how do you store optical disks so that they last?"
no they're not. ever hear of cd rot?
store everything on hard drives, with duplicate backups stored off site.
Claim up to 300 years.
http://www.smarthouse.com.au/Home_Office/Storage/U9P4F7L2
Currently, There is no better way than store a backup on DVD and store the main data on a raid-1 disk set. Move the raid disk set to new disks every few years.
All the other technologies are more expensive, and even possibly more dangerous (loss of data due incompatibilies or for any other reason).
Only wimps use optical media, _real_ men just upload their important stuff on ftp and let the rest of the world mirror it.
Build a simple storage array with RAID from a barbones PC, your favorite Linux distro, configured for fault-tolerant RAID. It doesn't have to be complicated, and it doesn't have to be powered on unless you're actually pushing data to it.
Every couple of years, you can add an extra couple of drives. With drive capacities increasing as fast as they are, cost shouldn't be a huge issue.
512 MB RAM, 20 GB disk, 200 GB transfer, five datacenters. $19.95/month.
Regardless of the methods you choose, I would highly recommend using at least two different media.
If these videos are important enough to be stored for 10 to 20 years, then they are important enough to be backed up - it is always difficult to foresee long term failures in any technology. If you read the article on tin whiskers they mentioned that some failures can not be tested using short time span methods.
Use multiple different media, with redudancy.
Store it on HDDs. Mirrored RAID like RAID 1 or RAID 10 is preferred. but even RAID 5 buys you some extra integrity protection.
Then back it up. CDs. DVDs. BluRay. Tape. Whatever. Multiple times, multiple ways. Every few years do some copies onto new media.
Keep at least one copy off of your premises. A safe deposit box might be good.
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As the other guy mentioned, CDs are still readable, almost 20 years later. However, they didn't have a viable alternative until about 10 years ago. I think that you will easily be able to find a DVD drive for many years to come, at least the next 20. The problem becomes ensuring that the actual media doesn't get scratched. I wouldn't trust DVDs to last that long, even if you just leave them on a shelf, away from the sunlight. If I was really interested in saving the stuff, I would put it on hard disks with at least 1 redundant copy, if not 2, stored in different places, and transfer over every 3-4 years. Still, it's going to be a lot of data. Your kid is only 1, and you already have 100 GB of stuff. Just think about how much that will balloon to once the kid has an attention span of more than 43 seconds. The first hockey game, all the school plays, all the other junk you could record.
Personally, I just don't bother with recording much. My wife gets on my case for not taking a lot of pictures with the kids, but I'd rather be interacting and paying attention, rather than trying to ensure we have everything recorded. Sure sometimes like during school plays you can record and not miss anything, but a lot of times, I find when I'm trying to take videos, or photos, I end up missing out on the actual fun.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
isn't long term storage, though it may have it. The strength is that you can reproduce it with high fidelity to the original numberous times.
The best way to store digital vidio for 20 years is to make numerous copies of it. 10Gigs is about 3 DVD's at the lowest density. Add a dvd of checksum files (something like a PAR) and you should still be able to make five sets for under $20 if you are shopping around for DVD media.
Once a year or three, load up one of the sets and run it through the checksums. Correct any errors discovered via the checksums and copies from the other sets, and make another five sets.
Volia. Repeatable as long as there is any sort of cheap digital recording media that can easily fit your files out there.
The real question is how you do this when you have 1,000 Gig to backup.
Step 1: Review video footage.
Step 2: Carve memorable/important parts into stone.
Step 3: ??? (commandments?)
Step 4: Prophet!
"Never let your sense of morals prevent you from doing what is right" - Salvor Hardin
Only professional CDs have that sort of shelf life, because they're physically stamped. The consumer grade ones use a type of photosensitive dye that DOES decompose in less than a decade.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
CD bronzing is a specific variant of CD rot, a type of corrosion that affects the reflective layer of audio CDs and renders them unreadable over time. The phenomenon was first reported by John McKelvey in the September/October 1994 issue of American Record Guide.[1][2] Affected discs will show a uneven brownish discoloring that usually starts at the edge of the disc and slowly works its way towards the center. The top layer is affected before the bottom layer. The disc will become progressively darker over time; tracks at the end of the disc will show an increasing number of audio problems due to disc read errors before becoming unplayable. CD bronzing seems to occur mostly with audio CDs manufactured by Philips and Dupont Optical (PDO) at their plant in Blackburn, Lancashire, UK, between the years 1988 and 1993. Most, but not all of these discs have "Made in U.K. by PDO" etched into them (see image). Discs manufactured by PDO in other countries do not seem to be affected. A similar, if considerably less widespread problem occurred with discs manufactured by Optical Media Storage (Opti.Me.S) in Italy. PDO acknowledged that the problem was due to a manufacturing error on its part, but gave different explanations for the problem. The most widely acknowledged explanation is that the lacquer used to coat the discs was not resistant to the sulphur content of the paper in the booklets, which led to the corrosion of the aluminium layer of the disc, even though PDO later said it was because "a silver coating had been used on its discs instead of the standard gold."[3] Peter Copeland of the British Library Sound Archive confirms that silver instead of aluminium in the reflective layer of the CD would react with sulpheriferous sleeves, forming silver sulphate, which has a bronze colour.[4] A combination of the two factors seems likely because, as Barbara Hirsch of the University of California points out, the oxidation could only have occurred if the protective lacquer did not seal the metal film and substrate well enough.[2]
Those were from Wikipedia, fact is, though CD rot can be a problem, it isn't as bad as people make it out to be.
Taxation is legalized theft, no more, no less.
Duct, Electrical, Masking or Transparent?
It must have been something you assimilated. . . .
Forget Wikipedia, ask the people who spend their lives trying to figure this out.
http://www.digitalpreservation.gov/you/digitalmemories.html
http://www.archives.gov/preservation/technical/guidelines.html
http://www.archives.gov/preservation/family-archives/digitizing-photos.html
http://www.archives.gov/preservation/storage/
Man, you got really upset over that RAID suggestion. With a name like 900ftJesus, I would have expected a more kinder, gentler approach.
Do not buy the largest hard drives that you can find. Cutting-edge storage densities might mean bad long term reliability. Go for something a little smaller than the leading edge that has had enough test time for you to find a large number of reviews on the drive's reliability. These will also be cheaper so you can buy two and store them at separate locations.
When you store your files, write a small utility or script that runs through them all and builds redundancy data, like QuickPar, and that stores a hash, e.g. MD5, so that 20 years later you can check the data is still good bit for bit, and even if it contains errors theres a high probability that you'll be able to correct it, even from the redundancy data stored on the same drive, let alone your second copy.
One important thing: As well as all of this, on each drive store a copy of the software (e.g. codecs), as well as any registration information to make them work. Backups of your files are no good if you can't play them later. Try to avoid storing video long term in any format that requires a codec with online activation. Will that company still be around in 20 years time?
Sometimes that video isn't just for you, who is able to be there every day with your child. Grandparents who are unable to be there every day with the child really like to see videos also. Also, not every waking moment needs to be spent actively interacting with your child. Sometimes they need some time to play on their own or with other children. Some of the cutest moments with my son have been spent watching him explore the world around him on his own (and subsequently get stuck in the tupperware drawer).
Norris/Palin 2012
Fact: We deserve leaders who can kick your ass and field dress your carcass.
Your experience is very interesting because mine is the opposite. I make (at least) quarterly backups of my data and have since mid 1993 (CDs since 98, floppy before that). This spring I got bitten by the curisoity bug and started going through all my old backups looking for forgotten and interesting things. Every CD older than two years had at least one unrecovereable read error. Every CD older than five years, except for one, was completely unreadable. Between two and five years the number of read errors grew with many files being lost and several CDs being unusable. The 3-1/2 floppies were all 100% readable.
In that time period I've been through probably a dozen CD burners, both expensive varieties and cheap ones, and I've used at least as many brands of media. All the CDs have been kept stored in dark, dry, clean places. I tried reading the "unreadable" CDs on multiple computers and met some limited success accessing additional data. I didn't try any recovery software.
Fortunately for me I kept most of these backups out of habit and I didn't really care about much of the older ones outside of curiosity.
I smurf everything and everything I smurf is perfect.
Any storage medium you choose will degrade over time. You should plan to transfer the data every few years. Choose a storage medium that is well-supported, cheap and relatively durable - DVD or CD for now. You should also pay attention to the format of the data. If you use a video format that is rare now, chances are you won't have a way to convert it to whatever new format you need in 5 years. When it's time to copy (probably 5 years for CD & DVD, to be safe), use the same guidelines to choose the new medium.
I'm amazed that no one mentioned it. Just get 16gb usb flash disks.
It has theoretically unlimited life for archiving. The only time it deteriorate is when you continuously write/erase it.
Low grade garbage consumer CD-R's do that. you can buy high end CD-R's that have a gold substrate and a permanent dye that are guarenteed to last decades. I have a couple of TDK archival quality CD-R's from the very early 90's that were burned on a god-awful-expensive 1X CD burner that are still readable.
Do I store them on my car's dashboard? nope. I store them in a cool climate controlled media safe. I can still buy high end archival quality CD-R and DVD-R disks that I am sure will last a long time.
And if the 3.5" floppy drive is any example, CD and DVD drives will be around for another 10 years at least.
Do not look at laser with remaining good eye.
Ok, I just went looking for the handbook I got with my photography course, there's a paragraph about optical media: The CD's with a greenish look are guaranteed up to survive for 1-3 years. The siverish CD's last about 10 years. And there are also more expensive CD's with a gold color, and a black protection layer on top, that last +/- 100 years.
It also mentions there is no durability data about DVD's yet. This seems strange to me, and it's maybe outdated.
It might be wise to get some advice at a photography store, I'm sure they get a lot of those questions.
"It's too bad that stupidity isn't painful." - Anton LaVey