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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'."
You're wrong. D-VHS is far higher quality. It's HDTV, whereas DVD is normal television resolutions.
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.
DEATH TO HELICAL SCAN MEDIA! <cough>
If you're using damnable helical-scan tape media (DAT, VHS, etc), repeated usage *will* get you to a point where low-level dropouts occur. Then life begins to suck. Yes, in principle one can use layers of ECC plus a compression algorithm and bitstream format designed for graceful degradation of the image in the presence of missing/corrupt data... but these tapes degrade relatively rapidly with just repeated regular use. Then consider the kinds of hell that tapes go through both inside and outside of the player... and this is even less appealing.
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 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".
Let me confirm what this guy says. I worked on DVD ECC a bit - there is a level of no return with it as well. It's also true that this stuff is going to come Mpeg 2 encoded (if not 4) as part of the standard - count on it. Heck - HDTV is already a compressed format over the air.
ECC can only get you so far- it is good for dealing with localized burst errors from the media. DVD's give you lots of errors too SUPRISE, but the ECC system (quite elaborate - much like that used for over the air transmissions by the way) is up to the task.
At some point - the tape WILL get messed up so that it exceeds the ability of the ECC to make up for the errors - and you get drop outs - nice BIG ones since it's going to be a compressed format!
Have you compiled your kernel today??