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DVDs On DAT?
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?
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
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.
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.
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.
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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?
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
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
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.
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.
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.
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.
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?
--I assume full responsibility for my actions, except the ones that are someone else's fault.
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.
Gentoo Sucks