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Can You Back Up Data On Audio/Visual Media?
O enrique asks: "Since digital video is becoming a popular issue, I wonder when would we put in practice the possibility to do file backup (non audiovisual data storage) into digital tapes using those firewire enabled cameras. Each 1 hour tape (less than 10$) stores more than 10 Gbytes of data! As far as I know, nowadays Linux is only able to grab data from such devices, but not to store into them. Well, it seems that some people already thought about it, but I've seen nothing complete. See the Web pages
here and
here. Is someone else interested on it?"
I remember a while back there used to be a system that pressed a standard VCR into service as a backup system. The data was recorded as a black and white pattern in the video, and that was recorded on the tape. A special cable was attached to the serial port and the data could then be retrieved. At least that's how the Amiga version worked :)
I'm sure it would be possible to make it work; the question would be at what cost (would new hardware be required? Those cameras I don't think were made to accept video from their USB ports, were they?), and the effort involved (Spend a fortune to save a nickel?)
Jeff
Jeff
Anybody else here remember using a tape recorder to upload/download software onto a PET, TRS-80, or an Apple II? And when you were loading a program, sometimes you weren't quite sure if the loading sequence had worked until it got to the end and you entered RUN.
"How many light bulbs does it take to change a person?" --BMcC-->
My concern with this method of storage is that of the reliability of the media. Since the tape is wrapped around itself on the spool, it tends to interfere with itself over time. I've seen this happen with regular recorded television programs on tapes losing clarity over time. It just seems to convoluted of a plan to store data. It'd be to unreliable for a corporate environment, which would prefer better systems, and slightly too expensive (if you don't have a camera and firewire connection) and complicated for home use.
http://www.ajwm.net/backfire/ The server has detected that you are using a browser that is incompatible with Internet standards (probably Microsoft Internet Explorer). The server is programmed to deny requests from such browsers.
I've backed up a couple of times to CDRW, but haven't found a way that is convenient or easy to restore. Recommendations anyone?
The difference between Canada and the USA is that in Canada healthcare is a right and gun ownership is a privilege.
A long time ago, I was at Greenbrier's Radio observitory and saw a VCR sitting in a rack. I asked what it was doing, and the guy replied that it was for recording data from the scope.
"Hm?" I said.
It turns out that they had sitting in the back of some 286 PC a card which would output digital signal over RCA cables and feed them to a VCR, which they would then mail the tape to Califoria. Damn cheap too.
Now why hasn't anyone out there made a standard 'backup' device akin to a VCR or Super 8 is beyond me.
III.IIVIVIXIIVIVIIIVVIIIIXVIIIXIIIIIIIIVIIIIVVIII
Digital video isn't like analog. You have to have all of the data to play the data back or you start getting digital remnants. Because of how the DV compression format works, it doesn't take much missing data to start getting tiling and just a little more to get stuttering and then a complete failure of playback. I agree that there is data loss in a DV cam, but it is all before the compression stage. After that the write and read must be almost perfect to eliminate quality problems.
I have great faith in fools - self confidence my friends call it. - Edgar Allan Poe
Check this and this
Early on, many discovered that they could use DAT audio tapes in their DAT backups with just a few modifications.
A little later on, many discovered that DAT audio tapes had nothing like the quality of DAT backups. One bit in a million is an acceptable error rate for an audio DAT. Even with matrix row/column checksumming and similar space-eating data safeguarding schemes, one bit in a million can be disasterous.
If these video cameras follow the model of digital music devices, they are going to be quite forgiving of errors in the media. It's easy to fudge a few bits here and there when you only need to be accurate enough to fool a human ear through a couple thousandths of a second, or a human eye for 1/60th.
I'll be wary of this until someone can verify that a situation similar to that of DATs doesn't exist here.
My first Unix experience was with SCO running on a network (UUCP) of '286 machines. The admin used a card that connected to a VCR for backups.
It sort of worked, but was very unreliable.
I suspect that the meia would be fine, but VCR's aren't really designed for data.
Jim Buchanan
Hello folks
.zip, rename it to .avi and then store it on the cam, and vice-versa.
.30$ / 700 megs, doing parts would render the idea of one big 10 gig file useless for all the troubles.
My friend and I already though about that. Since it's very easy to do on Windows, we tought it would be a great way to do backup and/or exchange huge files. The simple idea was to do a big
The problem is to retrieve only a part. Even if it's theorically possible to go to a precise frame and then, do a kind of "fat" which we could store at the first frame or first second, since the data on cd-rom is becoming
The data rate for an AVI-DV is approx 3.5 Megs/sec, allowing 12.6 gig of total space.
I think seriously that such a way to backup should really remain for hack purpose, because dvd writer becoming available for normal people probably in 2002. The price of dvd-r will probably drop a lot then (as cd first were 3$ each, now less than 1/10 of it's original price), it will make that hack useless.
But eh, I'll try it tonight
Get a clue.
Strictly speaking, this article should not be under the Digial category, but something more general purpose. When people say digital, they're talking about the company DEC (COMPAQ), and not digital media. Well, it could have been worse. I'm surprised it wasn't spelled "degital" or something. Peace out.
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a funny comment: 1 karma
an insightful comment: 1 karma
a good old-fashioned flame: priceless
this sig limit is too small to put anything good h
Hey guys, it's great to see someone in the tech community putting the earth first for once.
Our landfills have become clogged with decaying gifs of extinct corporate logos, and with the dotcom collapse, it's gettig worse. Combine this with the depletion of our natural swoosh reserves by short sighted marketers, and a crisis becomes imminent.
That's why it's good to see you lot reusing the digital logo.
For you young fellows out there, digital used to be the second largest computer manufacturer in the world.
--Shoeboy
http://www.anonymizer.org/surf_encoded/http://www. ajwm.net/backfire/
use anonymizer to hide your browser
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Video meliora proboque deteriora sequor - Ovidius
My first job after leaving college was looking after all the computers in an office of about 20 people. All the companies central and main systems ran on an "Alpha Micro" machine which yielded one page on the internet entitled "Obsolete Hardware". Most of the software for the machine was on tape (Exabyte) but some (which I never had to use) was on videotape. One day a new TV and video arrived in the building and guess what the only videos in the building were....So as soon as we tuned in the video we were looking at a black and white spaced table of I think 16x16 blocks at a rate of at most 4 blocks a second.....a grand total of 128kb/sec!
A simple demonstartion however of how this sort of a method with a firewire camera could certainly be used....it's just a question of what data-rate you can get!
Never underestimate the dark side of the Source
The compression on DV is basically colorspace reduction. It is a loseless format and not an mpeg style affair. It is good enough for most things, the only problm being the area of broadcast TV where the lack of depth is quite apparent and it would really be a station dependant decision as to whether the piece was worth it. You can certainly use a DV camera for data-backup, the question is how much error correction would be required to ensure data security and what data rate would that leave?
Never underestimate the dark side of the Source
They don't like Lynx either, the scum
If you're willing to experiment with using the wrong tool for the job, why not take a shot using the right, but used, tool? With a little bit of looking, you can find things like a 7/14GB tape drive for far less than a DV camera.
Defective Browser:
Access denied: incompatible browser.
Ironically, should be inside
If Mozilla would fix some of the REALLY bad bugs it has (such as considering form fields with display: none as "non successful" (check the HTML 4 specs), being unable to properly refresh DHTML pages, using native scrollbars in XUL widgets (combo boxes), taking a window 3 seconds to open, losing bookmark names when copy & pasting, etc.) and if Mozilla would get fast enough to actually be usable, I'd love to switch. Until then, I'll stick with the #1 browser out there.
Opera has a lot of potential too and I'm looking forward to their next major release but the current version has too many layout and JavaScript implementation bugs to be usable.
Netscape 4.. There's no point in even mentioning the ways it sucks and is non-standards compliant but for the sake of the argument, let's mention IFRAME's, DOM, 85% of the CSS1 standard missing in the implementation, *horrible* table rendering performance and correctness, form widgets being native and thus not z-orderable, Java VM being barely 1.0.2 compatible with a buggy 1.1 AWT implementation... Like I said.. it sucks in too many ways to even mention.
I should have used "preview" on my previous post...
<html>
<title>Defective Browser:</title>
<body><h1>Access denied: incompatible browser.</h1>
Ironically, <title> should be inside <head>..</head> so the *page* is incompatible with Internet standards. Meanwhile....
I think that tape drives are a technology that deserves to go the way of the punch card. While everyone talks about the speed of backing up on such devices, the amount of time that it takes to restore from one is rarely mentioned. And for good reason - on many of these devices, doing a full restore of 5GB or more after a drive death will have you scratching your butt for days (yes, that's plural) waiting for the damn thing to finish. While it's better than no restore at all, I don't think many people recognize just how long their critical systems will be down. In my book, the only mechanism worth using for backing up a single large IDE drive is another IDE drive! With plenty of fast 40GB UDMA-3 drives popping up on Price Watch for well under $140, I decided that in the long run it is much more economical to put in one of those removeable IDE trays and back up to a second (or incrementally, a third or fourth when you look at the cost of a 40GB tape backup device) IDE drive.
Maybe (if this is not directly possible) you could encapsulate the raw data to be saved in video struct : this way, any software aimed at exploiting these data would "see" proper video whereas an eye would only see some "noise" ?
Why "if this is not directly possible" ? I once used my camera's 32Mb Smartmedia card to store MP3 in order to carry these between 2 laptops and it has been unusable since then.
That's why I guess there might be a problem with some types of data.
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Trolling using another account since 2005.
The Exabyte 5 GB tape backup unit used the same tapes and mechanism found in 8MM analog camcorders. I wouldn't be surprised to see this happen with the new media, also.
In the 1980's my Dad got an Exabyte drive for his VMS cluster at work (ca. 1Gb back then, I think). The big selling point was the ease of getting media: standard 8mm video tapes. He tested various brands until settling on a couple that produced consistently good backups. He's been able to recover decade+ old backups from those video tapes, much older than the oldest 9mm backup tapes that still work.
Eventually I bought an Exabyte drive for the lab I sys-admined as a grad student.
Of course, manufacturers would love to FUD-you into buying their "data-grade" tape, but the video tape works just as well most of the time. I think Fuji and Maxell were good brands, but I'll have to check with Dad first. I've got Exabyte backups on video tapes; it's a very good system. Just remember that nothing is forever: re-tape your media regularly (which does not mean often, just regularly).
One night somebody broke into the pawn shop, saw the VCR, pulled the tape out of it, turned to the camera, smiled and waved. He thought he had pulled the security tape. The cops had a real good picture of him which was more than enough to put him in jail for quite some time.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
8mm backup machines have been able to use regular tape for a long time. my experience has been that these backup tapes can not be depended on. you need data quality media that was designed for archival purposes. but this is old hat.
A few years ago I picked up a device that attached to the parallel port and the VCR hooked up to it. I think it was called a "backer"? The thing never worked. I tried a few high quality VCR's but the error correction always screwed up.
Oh well,..not like I do anything important enough to backup anyway.
change me
just use a tape drive, with data quality DATs? HP has made them for years.
sulli
RTFJ.
What are you talking about? both Lynx and Links work just fine for me.
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Jesus, that is *so* 1997.
I thought everybody got over this browser superiority bit when they realized
that every browser sucks in it's own special way.
And don't give me this crap about Nutscrape being 'standards compliant', they did their share of embrace and extend.
This idiot needs to get a clue - don't exclude browsers, just write compliant HTML,
and if you're gonna take a stand against standards
violation, do it in a way that affects the company violating the standards, not the user that
may contribute to your project. A stupid 'denied' page is not going to get me to switch browsers -
it's just going to make me hit the 'Back' button.
--K
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I wasn't talking about mirroring in the RAID
sense, nor do I think that RAID is a good
backup solution due to the physical catastrophes
that can happen to a site - fire, flood, theft,
etc. When you take a mirrored RAID drive offline,
you lose synch and destroy the whole driving
principal behind it.
Just use the second hard drive just as you would
a tape drive, and then take it offline and into
safe storage at the conclusion of each backup.
Most backup software will talk to an IDE drive
just fine and treat it just as if it were a
(really really fast) tape drive.
My point of using a third or fourth drive for
incremental backups directly addresses your
"oops" concern. Or, if you're using a 10GB
hard drive and your backup drive is 40GB, you
can simply partitiion the 40GB and do rotation
backups to the same physical drive.
It really is no trouble at all transporting an
IDE drive once it's protected in a mobile tray.
Heavier and more fragile than a tape cartridge,
I'll grant you, but it's a small price to pay
for the relative benefits.
The real drawbacks to my scheme are that unless
you're using a special IDE controller and drive,
hot-swapping is a REAL bad idea. The system
must be shut down to insert or remove the
backup IDE drive. So perhaps a hot-swap SCSI
drive would be more appropriate for a 24X7
critical system. Secondly, doing this on a
Windows system requires extra care, due to
their goofy drive-letter reassignment methods.
I really can't think of any other drawbacks, but
I'd sure like to hear them if anyone else can.
Back in the early/mid 1980s[1], I got burned by one of these. It backed up a PDP-11/23 to a VHS VCR. Management[2] bought into this as our only backup for the 11/23s.
....
The first test I ran was simple:
1. Make a full backup
2. Delete a file
3. Restore the file from the backup
It didn't work. All it did was read through the entire tape and report "restore unsuccessful". No useful info. Bad tape? Maybe, but I tried with a couple of different tapes. My guess was that the software was only capable of handling "full partition" backup and restore, despite what the manual said. I assume (with no evidence) that *somebody* ran *some* tests before they bought into this.
To add insult to injury, they bought top- of- the- line VCRs, about US$1000 each at the time. The VCRs had been in- house for less than a week before they started disappearing[3]
[1] Yes, we had computers then.
[2] Pointy hair is timeless.
[3] I guess this was a self-solving problem, except that we had no working backup.
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Welcome to the Turing Tarpit, where everything is possible but nothing interesting is easy.
They are blocking my Mozilla browser because their detection routine is broken.
Idiots.
If tits were wings it'd be flying around.
...it affects the majority of /. readers who attempt to visit the second link mentioned in the article.
this would be nice to ask which media-specific peripherals/technologies could be used for other purposes.
For example, as a former Amiga geek I used to dedicate my MIDI setup to networking tasks (it was quick enough to play)...
And now, as a musician, I was wondering if somebody would create some AGP sound board in order to benefit from an even wider data bandwith (imagine yourself simultaneously sampling 64 CD-quality channels)...
Of course, sysadmin could also dream of even faster AGP-based network adapters.
Finally, the most realistic bit : the ones who are deseperately looking for some fine random number generator could also look forward to sample ambiant noise with their sound board. In this case we are dealing with easy-to write software.
--
Trolling using another account since 2005.
Well, the obvious solution is to write something that will convert tar files to aiffs (or pick your own favorite non-lossy format). This way, you can also *listen* to your data, just like Ellie Arroway in contact. It's like loading programs from casette all over again! And with ADAT, you could back up and restore up to 8 tracks simultaneously!
Tweet, tweet.
120 meter DAT-II tapes cost less than $10. Why bother with lower-quality media.
Vovida, OS VoIP
Beer recipe: free! #Source
Cold pints: $2 #Product
DDS-4 tapes cost about $20 if you buy them in reasonable quantity. This holds 24 gigabytes native (up to 50 gigabytes compressed). This works out to being a couple bucks less expensive per 10 gigabytes as compared to consumer tapes.
The DDS-4 drive is a bit expensive, but if you want a cheap drive (but more expensive tapes), buy one of the OnStream IDE tape drives (which sell for under $200 thru most discounters, and store 15gb native on a $35 tape). I haven't particularly been impressed by the Onstreams (to me they're the latest incarnation of the late unlamented TR-x technology), but they are still far more reliable than any consumer A/V tape and/or drive.
Exabyte once tried to make an 8mm tape drive that used 8mm camcorder mechanisms and tapes. It was horrendously unreliable, and forever soured many people on Exabyte and on 8mm tape backup in general. Exabyte learned their lesson -- their follow-on (the Mammoth series) and its tapes were engineered from scratch to be digital computer backup devices. It's sad that too few remember such lessons and would be willing to entrust their data again to A/V quality tapes and drives.
-Eric
Send mail here if you want to reach me.
I don't mean to be petty, and I don't usually complain about the minor errors that slip by on /. but...
The use of the logo of a company once known as the Digital Equipment Corporation for an article that discusses IEEE 1394 video cameras for data backup seems like a glaring lack of knowledge about the computer industry before 1998. (DEC was bought by Compaq in 1998)
While I wouldn't suggest striking the trademark Digital logo from the library as it may be appropriate for some articles on legacy systems, care should be taken that it isn't mistaken as a generic image for anything "digital" - in the opposite of analog sense.
--Aaron Greenberg
There is one way you could do this, however, which is if you didn't use the rename zip -> avi step and instead focused on tricking the camera into accepting data instead of pre-compressed video. IIRC, most DV camcorders essentially don't check their input for validity as a DV-format video. In this case, you just need to be able to do a direct stream copy of data into the camera's IEEE-1394 port, preferably with some error correction, which is what the whole article is about.
This is probably just as easy to do in Windows as in Linux, in that both (currently) lack usable programs to do this.
No, Windows 2.0
ANSI standard tapes haven't gone away. I worked on some ANSI tape utilities a few years ago. They were used on 9track, 8mm, DAT, IBM 3480(?), etc. Sure, it might not be as widespread as tar, cpio or some other formats, but many places still use them.
the good ground has been paved over by suicidal maniacs