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D-VHS to Hit The Market This Week
An Anonymous Coward writes: "Yahoo News is has an article stating that D-VHS is hitting the market this week. The upside: D-VHS supports full high-definition picture quality. The down side: $35 - $45 per movie (although available for less) and $2k for a player. Seems to me you'd lose a lot of that HD picture after a few viewings too. 4 studios are supporting it: 'JVC persuaded Fox, Universal, DreamWorks and Artisan to support the format after developing a new copy-protection standard it calls D-Theater to prevent unauthorized copying of the high-definition movies'."
I acually don't think you should lose any of the quality. This isn't VHS where it's stored in an analog format that degrades, I'd think of it more as a DAT tape with all digital data that should keep it's quality. Just keep it away from a magnet. Since JVC came up with it, and they own the patent on VHS, I'm sure the name came from that, and the fact that it's on tapes.
How many people have sets capable of rendering the signal at full quality anyway?
Maybe it would have had a chance before DVD authoring equipment became cheap, (assuming the authoring equipment for this format even exists for consumers), but otherwise this looks to be DOA.
The development costs will just be translated to higher DVD prices in a year.
This isn't VHS where it's stored in an analog format that degrades
Tape streaches. It flexes. It gets worn. It gets demagnetized. It tears.
The problem with VHS degradation over time has nothing to do with the data format on the tape. The problem is with the medium itself: flexible magnetic storage.
It's great if you aren't going to use it often, but if it keeps getting wound and unwound, wrapped around rollers, and pressed against a read head, it will wear out.
t'nera semordnilap
D-Theater is an option (feature) on D-VHS tape decks. There are already decks on the market, especially in Japan, that are D-VHS but not D-Theater.
D-Theater is a content encryption system. D-VHS is a recording format (MPEG-2 aparently). A D-VHS recorder would allow you to record any HDTV broadcast directly - up to 4 hours of it in fact. Also, D-VHS supports full Dolby Digital 5.1 soundtracks at a bit rate of 576Kbps (higher than DVD's 448Kbps rate). This is being touted as the VHS for the HDTV generation.
Also, while the titles are listed at 35-40 USD Buy.com and BestBuy have them listed at 25-29 USD, so they aren't terribly more expensive than DVDs. Even so, DVDs have market edge on D-VHS (and a few other technological advantages including durability). It seems as if D-Theater is unimportant, but take notice of D-VHS.
Just like DAT made its way into the consumer sector so well, I would expect D-VHS to do the same! With prices like these, who could resist!?
Now, really, I see this taking the place of Beta, MiniDV, and D8 in the content-creation field. It could be rather good for them, because it provides digital video (something Beta doesn't) along with HD support, something MiniDV and D8 can't.
± 29 dB
You're wrong. D-VHS is far higher quality. It's HDTV, whereas DVD is normal television resolutions.
Some of the currently-available D-VHS decks support FireWire I/O. This allows one to record and play video to the deck with a computer (the streams can be recorded from the deck - e.g. for PVR-style timeshifting of HDTV - or generated and encoded yourself).
Several people at avsforum.com have already gotten this working using MPEG2-over-FireWire support built into Windows XP.
Dan Dennedy and I are working on a Linux driver that will provide the same functionality as Windows XP. (it will appear at linux1394.sourceforge.net; it's not ready for release yet though).
D-VHS is a truly versatile format. The deck I have experience with (JVC) can record and play MPEG-2 streams at a wide variety of bitrates (up to 29MBit/sec) and formats (720x480 NTSC up to 1920x1080 HDTV)... The encoding is standard MPEG-2, so you can make and play your own HDTV content (I've done it already), and you could probably also do things like record a DVD to tape without re-compressing the video.
Note however that Windows XP and my drivers can only handle cleartext MPEG-2 streams (either home-made or recorded from broadcast/satellite HDTV). The new "D-Theater" standard is basically like DVD's CSS; the MPEG-2 streams will come in a scrambled format that is "impossible" to read without a licensed decoder.
Won't they just have a "re-tension" option on the players?
The problems are streching, physical contact, and frequency of use.
If the reader expects each bit to be X distance from the next, but the tape streches, then the read head will read some other magnetic data from the extended area. The same goes for wrinkling and bending.
Tapes are more likely to sustain this kind of wear since the process of using them involves physical contact. Take a look into an open VCR as you insert a tape. Those metal rods can damage your tape. They pull and flex the tape. The head can also damage the tape. The motors can damage the tape if they pull to hard an the tape reaches its end, resulting in a harsh jerk.
The reason that these problems are less likely to plague backup tapes is because of frequency of use:
How often do you insert each computer tape? Remember that the act of inserting the casette into a VCR causes physical contact with the actual tape.
How frequently do you use the tape at all? Don't you just write to it in most cases?
Don't you only read from it infrequently and usually only once? When you re-write the tape, it can make up for some streching (within certain limits).
More importantly, how often do you "pause" a data tape? Pausing streches tape.
How often do you run the tape at high speed while the read head is in contact with it? That is exactly what happens when you scan tapes by pushing ff or rw in play mode. That is even more damaging to the tapes than just playing them.
Sure error correcting exists, but my point is that tape is more error-prone than other forms of storage since the simple act of reading or writing the data can degrade it.
t'nera semordnilap
Wow, that's an incredibly uninformed "clarification".
In terms of performance/quality, there is no clear difference; they are both digital video formats
Wrong. DVD is 480i (720x480, interlaced), and can be translated into 480p (progressive scan) by the DVD player.
D-VHS supports HDTV resolutions, including 1080i (1920x1080, interlaced; the most common format), and 720p (1280x720, progressive scan). 1080i is over 4x the resolution/quality of a DVD. THAT is the reason people are interested in this.
With D-VHS, there is no easy tape-to-computer interface
Ever heard of IEEE-1394, aka Firewire? That is the interface that the D-VHS VCR's use. I have read reports of people using these with the Linux IEEE-1394 support, and they also work with XP.
This is very close to DIVX
How so? DIVX had all kinds of features to get more money out of viewers, like charging more if you wanted to view the movie again. D-VHS has nothing like this. It only has an encryption to prevent making copies of the movies (as do DVD's, albeit a very weak scrambling method).
Manufacturer's suggested retail price: $1999.95
JVC's upcoming HDTV-capable Dish Network receiver will also have a IEEE 1394 (FireWire) connection so it can transfer content directly to the D-VHS box.
That is correct. The JVC D-VHS deck actually supports a range of resolutions - 720x480 (like DVD) and several HD formats up to 1920x1080 ("1080i" HDTV). It is my understanding that D-Theater commercial releases will be encoded at the full 1080i resolution.
It would be insanely cool if the D-VHS deck's MPEG-2 decoder could understand 3:2 pulldown flags, and generate a true 24fps output. With the right projection system you could essentially get the same image quality as a digital cinema movie theater in your own home! (but you'd need to play it at 1080p (60 frames/sec) or 24p (24 frames/sec), which are unfortunately beyond the range of consumer-level HDTV equipment...
Stupid? How about condeming a technology you don't know $#!+ about. That's stupid.
D-VHS is an established standard. It has extremely limited acceptance at this point, as it's primary use is for HDTV.
It is not uncompressed HDTV. You can't deal with uncompressed HD in a consumer environment. You can't even deal with uncompressed SD in a consumer environment. Uncompressed HD is 1.5Gb/s, SD is 270Mb/s.
It does not beat DLT in speed, and it might beat it in storage, but it doesn't beat Ultrium.
The tape is physically identical to S-VHS, which works just fine in a home enviroment, thank you very much. It tops out at 28Mb/s, and the promise is that D-Theater releases will use all of that 28Mb/s, as compared to the ATSC (Broadcast HDTV) limit of 19.3Mb/s. And let me tell you that full 19.3Mb/s 1080i is very, very nice as it is.
Oh, HDTV is MPEG2 compression, just like DVD.
And how much random access do you really do on a DVD? Truly random access is locked out by most studio authored DVDs anyway. (It breaks scripting.)
-Z
You have violated Robot's Rules of Order and will be asked to leave the future immediately.
Wow, there's a lot of FUD floating around here..
D-VHS is currently the only format that allows true High Definition resolutions in a removable format. It allows you to record HD content from a HDTV Set Top Box (if the HD receiver is equipped with a firewire port). It also allows playback of pre-recorded movies at 1080i resolution.
DVD's don't have the storage capacity to hold an HDTV movie. Broadcast HDTV is about 9GB per hour. Pre-recorded movies on D-VHS will be even more than that, up to twice the bit rate of broadcast HDTV.
DVD's are at best 480p (720x480), the D-VHS VCR supports HD resolutions, 720p (1280x720) and 1080i (1920x1080). The HD movies are over four times the resolution/quality of DVD's. The difference is very dramatic.
This variant of D-VHS, D-Theater, includes an encrpytion, to stop the pre-recorded movies from being copied (much like CSS was supposed to do with DVD's). That is the only restriction that this format has, which is a welcome change from all the other attempts to control HD content.
The JVC unit also has analog component video outputs, allowing 1080i playback on all existing HDTV's. This capability is one that Hollywood has been threatening to disable in HD receivers (block the "Analog Hole").
If you look at the statistics for HD capable TV's sold vs. HDTV Set Top Boxes, you'll see that most people with the nice 16:9 HD-Capable TV's are not using the full capabilies of their TV's. They are just using them for DVD's. D-VHS could be the first chance for them to really use their HDTV.
If you used LaserDisc, you're probably the target market for this product. This is aimed at the 'videophile', who wants the best quality possible. The people that have the expensive, 16:9, HD capable sets.
This is not meant to replace DVD's.. They are still in the process of milking that market. And, D-VHS has obvious disadvantages in flexibility.
A few years down the road, we will have HD-DVD, which will have the storage capacity for a full HD quality movie. Until then, some of us will be recording HD, and viewing High Definition movies in this format.
I'll gladly retire the D-VHS at that point.. but I am not willing to wait the several years until HD-DVD is here to have my 1080i movies.
It's tape! Gaaack!
The reason you have this attitude towards tape is that analog tape suffers degradation over time (tape becomes worn, quality degrades over generational copying, etc.). Keep in mind that nearly all music producers master to DAT first, which is similar to DVHS. D, being digital, means zeroes and ones are getting stored, and they don't degrade much over time and have almost zero noticable artifacts between generational copies. DAT master tapes sound the same after 1000 times of being played, unlike analog cassette tapes you're used to.
I can see DVHS being handy for TV stations replacing Beta, but not much else. Who needs another format in this day and age? Sure, maybe you can copy your favorite stuff in full res from your satellite now, but overall DVD has more advantages.
It will be released then, ta dah!, on BETA tape, Digital BETA too. Why, because that's what the professionals use, and have done for years. (You thought the cable company digitized off 35mm film?)
True, most professionals still use Beta... however, and as you somewhat pointed out, they mostly use Digital Betacam ("DigiBeta") and Betacam SP. Both are uncompressed and are more than enough to store NTSC/PAL as good as they'll get. There is no need for anything greater unless you're ready to go to HD. (A side note... while Betacam SP is as good as uncompressed analog gets, DigiBeta came about as a lower cost replacement to D1, the original full-quality digital tape -- however D1 decks easily cost $400K+, an hour worth of blank tape - $400. DigiBeta is a dream come true for mid-sized video firms... NTSC as good as it'll get, uncompressed, and ready for the editing/compositing workstation. Betacam SP looks just as good, but because it's analog, requires time-consuming digitizing before it can be worked with on a workstation or PC/Mac.)
There are many other forms of Beta... including the new Betacam SX (which is compressed digital and suffers from the same compression artifacts that pop up on other similar compressed "DV" formats -- Digital 8, MiniDV, DVCAM, DVCPro. "DV" formats are great for home and small business use, with a compressed data stream of about 25Mbit/sec... but it's often loathed by pros due to artifacting and compositing work. Basicly, if you want full quality, go uncompressed. RAID storage is there, workstation hardware is there. Leave the comprssed stuff to Win/Mac users with their FinalCutPro-type software. Real users want DigiBeta and an Onyx3000 running Discreet Inferno or IFX Piranha.).
Anyhow...
Beta came (somewhat) popular with the release of 1/2" consumer Betamax, based off of the similar but much more expensive 3/4" U-MATIC decks. ED-Beta with 400 lines of resolution came out a few years later. Betacam followed with about 440 lines. Betacam SP with nearly 500 lines followed, providing more than enough quality for broadcast/archival NTSC. With the advent of Betacam SP (and competing Panasonic M-II) the video world began to improve optics as the tape side of things was already as good enough. Though you'll still see a lot of spec sheet padding and other BS when various vendors talk up their "lines of resolution".