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Hardware

DVDs On DAT? 29

Posted by Cliff from the why-not? dept.
Guppy06 asks: "The big question about copying DVDs (other than legality) seems to be "What do you do after being able to decode it?" A cursory scan of Pricewatch shows that DAT tapes are now big enough to hold the entire contents of a DVD and then some. I know that tapes in general have been relegated to the back-up role because of their slow search times and, to some extent, slow read/write times. However, you don't exactly need ATA-100 (or even a 12x DVD-ROM) to watch DVD-quality streaming video from start to finish. So, my question is 'Would it be possible?' If not, what's standing in the way, and are those problems long-term or short-term? How fast are read/write times on DATs increasing, if any? DATs are an ancient technology (by computer standards), widespread, cheap, and not easily censorable in the near future. It might be a better alternative to bending over for the MPAA for playing/recording large media files." As long as the data transfer rate is sufficient for real-time playback of a DVD, I don't see why something like this can't be done. Of course you will lose the searching capabilities (playback in a differing speeds both forwards and backwards), but when you are just playing a DVD, do you really need those?
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DVDs On DAT? More

DVDs On DAT?

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  • Jeez... (Score:1)

    by Anonymous Coward
    Ferchrissakes... Just go drop a few hundred on a PS2 and watch the DVD. What's the deal with you guys wanting to copy these things anyway, you've already got the DVD, right?

  • Indigita (Score:3)

    by Anonymous Coward on Wednesday March 28, 2001 @11:40PM (#331968)
    http://www.indigita.com/ Indigita makes a DAT drive speciffically made for this type of stuff. It's called the RAV6 and comes in IDE and SCSI configs. Writes to standard DDS-2 tapes and shows up as a drive letter. They specifically mention being abel to copy and run DVDs. I couldn't get to their homepage at the time of this posting but I know that pcconnection.com sells them. Just search for Rav6. Taffey Lewis taffeyl@hotmail.com
  • Doesn't DV use mpeg 2?

    No, DV actually uses an encoding similar to (but not the same as) motion JPEG. So, like MJPEG and MPEG it uses discrete cosine transforms to compress individual frames, but unlike MPEG it does not have any temporal compression. Frames are recorded individually, which requires a much higher bit rate (25 Mbps) than MPEG2. This is good for editing, but not ideal for storage.

    Why reconvert?

    DV is a standard format, you can buy recorders and players (including portable decks) that won't be unique to your personal setup. Downside: recompression and different colorspace divisions (4:2:0 on DVD, 4:1:1 for NTSC DV) will hurt quality slightly.

    There wouldn't be any space savings, would there?

    Definitely not, and if you're using MiniDV or Digital8 tapes you'll get at most an hour per tape, so 2 tapes are needed for most movies. The larger DVCAM tapes can hold 2 hours or so, but are much more expensive than most DVDs.

  • Yes, I want to convert my DVDs to a format that gives me fewer features than VHS. (Do I _need_ searching? Probably not. Do I use searching? Yes. Do I like searching? Yes.)

    What's the rationale here?
  • The only real problem with using DLT's for piracy is it entirely defeats the purpose. A $15 legal copy beats paying $90 for a DLT cartridge to store an illegal copy, methinks...
  • Then who cares really? Just store them on their original media. Unless you want to do streaming, and then hard drives are your best bet. As another poster pointed out, you can set up a streaming server (For your lan... you'd need a pretty sexy pipe to stream over the 'net) and the storage would cost $10/movie. The random access would be much easier that way; you wouldn't need a tape robot to not have to get off the sofa. That would be cool.

    If you really want to pirate movies (as long as DVDs stay cheap, why would you? They're cheaper then mucic CDs!), are you sure a public forum is the best place to discuss it? The MPAA has more money then the Church of Scientology...
  • The larger DV tapes are 270 minutes - 4.5 hours, but need to have a deck capable of using it.
    My VCR has 2 bays - VHS on the right and DV on the left. The DV bay will take either DV or Mini DV.
    I'd love to find a Linux solution that will stream out the firewire port to the deck's firewire - Since the deck refuses to record MacroVision streams, I'd have to strip that out of the video, without going to analog. (The DeCSS version I use strips that.
    Anyone know of a solution?
    (Oddly, the main reason I need this is not to pirate, it's because I am really hard on discs...)
    Cheers,
    Jim
  • This exists, and has for awhile. It's called DV (Digital Video), and is what gets passed across firewire, is used by digital camcorders (although Sony also has the option of using Hi-8 cassettes in their D8 systems), and sits on a DAT quite nicely.

    It also is about an hour per tape... two tapes per movie (or one tape per episode of Junkyard Wars!). Sony makes a VERY nifty device that encodes various formats to DV... it's referenced on Apple's site with their high end Macs.

    And yes, most DAT drives for backup purposes are around $1000... I have two, one for home use, and one at the office. The tapes are dirt cheap, however. It would be possible to do this with an MPEG-1 or MPEG-2 stream, but the listed capacity is generally pre-compression (the backup devices compress on the fly onto the tape).

    I have a friend who is wholesale converting his large videotape collection to DiVX ;-) on CD-Rs. That seems to me to be the best solution... we often watch Anime on his 'Toshi-chan' laptop at Dennys or other restaurants. Gets quite a few looks, but is fun.

    --
    Evan

  • There wouldn't be any space savings, would there?

    Definitely not, and if you're using MiniDV or Digital8 tapes you'll get at most an hour per tape, so 2 tapes are needed for most movies. The larger DVCAM tapes can hold 2 hours or so, but are much more expensive than most DVDs.

    Well, technically, the tapes are actually very small, and in many cases, two tapes are easier to pack than a jewel case. Of course, the tapes are heat sensitive, and DVDs can fit very nicely in CD binders...

    And just in case anyone thinks I'm 'defending' this solution, I'll reiterate that I think backing up to CD-R using one of the recent high compression video codecs is currently the best solution, but that will likely change before the year is out. You can play them on just about any laptop without any additional fancy hardware investment.

    Sure, DiVX ;-) is not truly open source, but there are now variants that are. The benefit is that you won't see the format fall by the wayside... you will always be able to read it.

    And I just thought of another bad trait of using tapes for movies - you generally have to have yet another power cable, meaning another outlet, which also generally precludes using portable gear to view them (a DVD->CD-R rip (if you have a laptop without a DVD drive) can mean bringing your own movies on flights or car trips).

    --
    Evan

  • well, if you get a PS2 try and make sure that all actions are taken in a clean room, and the disk is new, otherwise it might be a bit hard to play
    (damn I hate it when I rent a movie and can't play it on my PS2!)

  • DLT's are used to make new pirate DVD's, I don't think anybody actually views them.

  • they already have that, sort of (Score:3)

    by Spectr3 ( 29559 ) on Wednesday March 28, 2001 @06:43PM (#331978) Homepage
    They're called DLT's, Digital Linear Tapes. Probably somewhat comparable to DAT's, but almost certainly not compatible. DLT's are used in the production of DVD's-everything goes on a DLT right before the master DVD is pressed. Apparently, DLT's are the main enablers of DVD piracy, not DeCSS (big surprise there), so it might be possible to get your hands on a DLT player and maybe even a recorder, if you're into black market dealing.

    Anyway, is it even possible to store/playback video on DAT's? Seems not to smart to me.
  • Or if you are not into black market dealing you could buy a DLT drive from any one of 1000's of online/meatspace computer hardware vendors...
  • That pisses me off too, Imation are now labeling their new tapes with the compressed size and putting the real (native) size in tiny letters at the bottom.

    Bloddy annoying!

  • Re:Jeez... (Score:3)

    by robbieduncan ( 87240 ) on Thursday March 29, 2001 @05:23AM (#331981) Homepage
    In the UK (and probably the rest of Europe) I believe this already operates for Playstation (1, havn't checked the fineprint on the agreements on games fro PS2). You simply mail them the scratched disc and they mail you a new one. Have never used it so no idea how easy it is in practice though.
  • Doesn't DV use mpeg 2? Why reconvert? There wouldn't be any space savings, would there?

  • Re:Jeez... (Score:3)

    by Catbeller ( 118204 ) on Friday March 30, 2001 @02:04PM (#331983) Homepage
    No, no NO: there is a difference between a car and a DVD. Legally speaking, a car is a lump of metal, and you bought it, tough noogies if it gets broken. But media, especially movies, that we purchase we can legally copy for backup or personal purposes. Legal cases fought for, and won. What the DMCA has done is make even the mere analysis of the encryption used on DVD's illegal, so the so-called Fair Use copying of your DVD becomes impossible. The RIAA and MPAA have sidestepped Fair Use by making the method necessary to decrypt media illegal to even look at. So copies cannot happen, even tho you are legally entitled to it. So if your DVD breaks, or your New Shiny Encrypted Audio CDs have a scratch, too damned bad. And they are winning the PR war in papers, TV, and online news services, who regularly describe people trying to copy their own damned disks as "pirates".

    A nastier effect of the legal underhandedness in the RIAA/MPAA/SPA war against Fair Use is the fear on the part of manufacturers of producing digital storage or playback units that can store video or audio. Where the hell are the hard drive-equipped audio components that could store 10,000 MP3's? Where are the laptop-dervived audio units that should play MP3's in my car? The manufacturers are afraid of getting sued, under recent legal precedent that even MAKING equipment that could facilitate "piracy" is de facto illegal becaues the MPAA/RIAA could possibly lose 2 cents. The *possiblity* is all that is required now in court, and the manufacturer could be liable for damages.

    This is getting sick.

  • Where are the laptop-dervived audio units that should play MP3's in my car?

    Not sure what you mean exactly by laptop derived but these will give you mp3's in your car!:
    • E-Mpeg [empeg.com]
    • MP3 Car [mp3car.com] (okay they are home made, but that's more fun isn't it?)
    • Mega Car [megacar.com] (probably out of your price range! I recall this car being worth $300,000)
    • I know of others but I'd have to go find them some of which are from big name audio companies.

  • Re:Jeez... (Score:4)

    by mini me ( 132455 ) on Wednesday March 28, 2001 @06:31PM (#331985)
    And what happens when that DVD breaks, gets scratched, etc.? Do you have to shell out (whatever the price of a DVD is, my DVD drive has never even seen a DVD before.) again just to have the media that you were only licencing before? Maybe if you owned the contents of the disk it may be worth spending the money, but since it is just a licence to use the contents of the disk it isn't. Maybe the MPAA should have to replace unusable DVDs?

    As I understand it you are legally allowed on copy for backup purposes. This just might be the backup solution suitable for DVDs.

    Now more on-topic: I would assume a tape drive would have a high enough transfer rate for full motion video and it really wouldn't be that hard to hack up some software to read/write to a tape drive with video data would it? The problem I see is drive noise. I'm sure there are quiet ones out there, but the ones I have experience are rather loud. So unless the computer is far away from your viewing area the noise might be less than desireable.
  • And what happens when that DVD breaks, gets scratched, etc.? Do you have to shell out... again just to have the media that you were only licencing before?

    Now THAT would be nice.. at CD/DVD replacement program for a dollar or so a disk. Yes, I suppose I could use CD-R's, but then I would have to burn them ahead of time... too late if the CD gets damaged. Not worth the effort and aggrivation. And forget the price on DVD-R's. Just mail in the damaged CD/DVD as proof, and they replace it. Anybody know if any of the labels have a deal like this already?

  • You can buy a 20 GB tape drive for $500 or so (type "dds-4" into ebay's search box) but the tapes will run you at least $20 each, and that's also scrounging them on ebay. If you buy them from dealers they're much more.

    You could also look at an Ecrix [ecrix.com] drive, about $500 through the LUG deal [ecrix.com], which stores 33 GB on an 8mm cartridge costing $65 or so (ouch). I've heard of people punching holes in hi-8 video editing tape (Sony HMEAD E6-120, about $13 per tape at B&H Photo) and getting good results with that. The 120 minute video tape holds about 20 GB since it's shorter than the Ecrix tape. Still, this is kludgy and maybe flaky. Basically all tape media are overpriced right now. CD-R is a lot cheaper, but the capacity is too low to really dub video in style.

    It's probably best to just wait for recordable DVD to get cheaper. Recordable DVD is available now, but costs a lot. Consumer products are coming though, and within a year or so it will be like CD-R.

    Finally, there's good old analog videotape...

  • Well if you really want this to work, you should also place the contents of the DVD on 5000000 DISks. Then you could have the DVD on DIS(ks) and DAT.

    No Applause, just throw money.
  • 70GB compressed means 35GB of real data.

    Tape marketers are scammers.
  • It could be made to work. The DVD transfer rate is 1.32 megs/sec, so you need at least that much. Looking at the specs for Seagate DDS drives, they should have enough transfer, but you need to get a pretty high-end drive. Most of the cheaper drives don't have enough transfer rate. Remember that they generally show the transfer rate specs as compressed, and that's not going to work with already compressed MPEG2 data too well.

    I have a sneaking suspicion, however, given that the cheapest DAT drive that's fast enough is over $1000 MSRP, you might get better results just using a DVD-RAM drive for your MPEG-ripping enjoyment. The media's either as expensive or a little more expensive than DAT (You can get DDS2 and DDS3 media, but I have a sneaking suspicion that the DDS4 -- $19 on PriceWatch -- media is required to get the required transfer rate) and the drives are $300-400.

    So, really, the DAT drive seems to be a better deal. Unless you already have the drive, it's not worth getting one.
  • And what happens when that DVD breaks, gets scratched, etc.? Do you have to shell out (whatever the price of a DVD is, my DVD drive has never even seen a DVD before.) again just to have the media that you were only licencing before? Maybe if you owned the contents of the disk it may be worth spending the money, but since it is just a licence to use the contents of the disk it isn't. Maybe the MPAA should have to replace unusable DVDs?
    I don't agree with any of the MPAA's tactics, but I find most arguments for copying DVD equally inane. This is one of them. What do you do when your brand new car gets in a wreck? You replace it, not the manufacturer. Warranty problems are another issue, but this is handled the same way. If you buy a disc and it doesn't work out when you get home you can replace it. If you buy it then use it on your rotary sander you don't get a free replacement.
  • from a cursory glance around the internet, DLT's seem to be capable of storing up to 70 gigs, compressed. when you consider 10 movies on a single tape, the economics begin to make a bit (but not much) more sense.
  • I say you try to stream a ripped DVD from a Ditto drive. That will work!
  • Pricewatch shows regular IDE drives 40GB @ $100 = $10/movie (assuming 4GB movies)

    After factoring the cost of the Tape Drive, the Media, the empty area on the end of a tape that is wasted, and the time or money for the software to perform the playback, looks to me like you should just buy a bunch of cheap hard drives and copy the files. If you are worried about data recovery, use RAID-5, even with the extra $100 I think it'll come out cheaper in the end. Plus, with hard drives, you'll have many different options to play back the video. Better yet, get an external setup and take your movies to your friends! Hey... maybe there's a new product there...
    --
    He had come like a thief in the night,
  • I've got nothing against a nice hack, but this just seems like far more trouble than it's worth. As mentioned above, the price of a decent DAT drive brings you within striking range of a DVD burner, and if not, it will certainly in a few months. Besides, now you've managed to strip the DVD of all random access and interactive features (When my girlfriend made me watch Stewart Little, at least there was a little game off the menu that I could enjoy.) Another drawback is the lack of a remote control. And finally, I love the speed of the DAT drive I have at work, but it ejects tapes annoyingly slow. jelling (Also, is it safe to assume that the DAT will be able to output 5 channel audio?)

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