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Discussion Starter · #1 ·
You know, doing my job is nothing short of sitting around and doing nothing until the sky begins to fall. And, its times like this, while waiting for anything to fall, that I get some crazy thoughts to go through my head.


Of course, this happens when I'm asleep, too, but thats another story. I just re-read the WSR May issue article on D-VHS D-Theater. I also spent the last couple of weeks looking at the market condition for JVC's DH30000 D-VHS unit.


I see politics at play with JVC entertaining the studios with the 'safe' concept of using magnetic tape as the medium of choice, because the studios like any storage medium that can be pushed onto consumers that have an knack for deteriorating over [a very short] time.


Of course, the decision to use a digital VHS storage/playback path is clouded in a couple of simple facts, and as true as they appear, they only serve to deviate the public's attention from other, more creative solutions for recording and playing back HD materials.


True, the current DVD standard is wholy insufficient for storing HD-DVD when using bit-rates above 10 Mbps. And yes, tape provides sufficient storage capacities for four (4) hours of HS-mode recording (at 28.2 Mbps). These are facts, but these facts are used against out creativity.


Thus, when it came time to decide on a physical format for delivering HD prerecorded materials to the consumers, JVC thought magnetic tape was the only way to go. Blue-Ray is still, admittedly, some time away and MPEG-4 DVD is the DVD Forum's way of showing their desperation.


It is with this in mind that my little geek-of-a-mind wandered to the early days of storage technology. I remember hauling some old computer components (I'm not that old!), including some 8-inch floppy disk drives. My mind (or what was left of it) continued to wander to the laserdisc history and how its physical footprint did not stop the consumers from buying.


Now, I really started to wonder why not simply continue with the DVD transport system, but a slightly different disc footprint? We are use to seeing the 120-mm disc when they were introduced for music compact discs. So, I now wonder why JVC, or anyone else, could not simply [offer to] adopt something like a 200-mm disc?


Since recordable DVD undoubtedly will reach a market-forced standard within the next 12-18 months (look what happened to betamax), a re-writable 200-mm DVD disc for recording HD seems plausable. So why not?


Well, the studios are why not. The last thing the studios want is to release into the wild are HD copies of their products that could be used for ease of replication (i.e. bootlegging). I cannot blame them as I would take the same position if I were in their shoes, but I'm in the consumer's shoes. :)


Hence, a tray-based 200-mm (that about 8 inches) could conceivably provide the storage capacities in the same ballpark as Blue-Ray, and the same player would be backwards compatible with traditional DVDs. And, because the market is crossing the threshold of recordable DVD dyes, the ability to 'have our cake and eat it too' covers all bases.


No, I am not suggesting that we return back to the laserdisc footprint, but only part of the way. What do you'all think? She we poll the forum's interest in such a product?
 

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I know one thing that retailers were very happy about with DVD & CDs, was the relatively small footprint and therefore display space required. Likewise, the public liked the idea in terms of not requiring much space at home. This may be a factor in why the idea may not be that appealing to the manufacturers or retailers. I actually think it's a pretty damn good idea!
 

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Discussion Starter · #3 ·
Ken, you speak of truth and I agree with you to an extent. Keep in mind that one of the reasons why some of the consumer market was willing to move away from magnetic tape in the first place was shelf-life of their bought CD/DVD.


I thought the 8 or 10 inch DVD disk would be easier to accept by the consumer market since it, unlike D-VHS, is not backwards compatable with the current strong-contender, which is DVD.


Surely someone 'in the biz' must have had this idea long before I got bored this afternoon. Maybe the decision not to go my suggested route is because of the politics?


Anyone want to make a 8" HD-DVD player/recorder?
 

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Why on earth would you want to do this? A small chip change, some different firmware, and the current MPEG2 DVDs could play on a player with MPEG4 based HD. Be a lot cheaper to implement, and a lot easier to market (no real change in core functionality). Hollywood resistance would be the same. Not really any different than a DVD / CD player is currently.


Mike
 

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Discussion Starter · #5 ·
Excuse me, but the DVD forum somehow thinks that 7Mbps MPEG4 compression is acceptable. I do not share their acceptance, nor do those four Hollywood studios accepting of the 28.2Mbps HD movies they are releasing come May 28th.


Also, there are some unresolved licensing issues attached to the MPEG4 scheme which would make is somewhat expensive. The idea is to exceed current broadcast HD and MPEG4 (when DirecTV implements it) will be worse. Mike, have you read the WSR article in May's issue?


Besides, how expensive can it really be to simply elongate the radial arm of the read/write head. Not much in additional engineering is needed. Also, this is not an alternative to MPEG4 discussion, but an alternative to D-VHS using existing technologies. Increasing the compression does not help the matter, but makes it worse--which is JVC's entire basis for D-VHS.
 

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A disc that is optically compatible with DVD would be difficult to manufacture in a larger diameter. One of the things that happens is that the disc warps into a circular pyramid shape. DVD-RW drives today require a "tilt servo" which senses and corrects for the slight variation of disc tilt as you move from the inner diameter to the outer diameter. This sensor and mechanism significantly increases the cost of the system. This effect would be worse with a larger diameter disc. Remember how rigid LDs are? CDs and DVDs are relatively flexible in comparison. I don't think it's practical to make discs of CD/DVD thickness any larger diameter. Not to mention all the other objections regarding pysical size and retailing above.


On the other hand, I don't see why the existing DVD optical specification is so bad. D-VHS capacity is only about 23GB, right? DVD with all 4 defined layers is 18GB. So you have to flip the disc... what's the big deal? Why not use multiple discs? Clearly the transfer rate is there, why not just increase playing time with additional sides and/or discs? Multiple disc DVDs are out there for bonus material, but they are terribly under-utilized because they label one side instead of recording on it.


- Mike
 

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Are there folks here who would not purchase an LD sized medium with low compression , nearly pristine quality, transfers. I would. I'm still in the mode that if it is reasonably convenient and gives that kind of picture and I can watch when I want ,bring it on! I would rather have random access on an LD sized medium than tape if they were equal in the quality that they would present, let alone an 8" or 10" variety. It almost would seem more logical to go to big DVDs rather than" tape until blue ray mentality". I just don't want to see some highly compressed "HD light" that could appear. I'm so tired of talking about the compression related issues on DVD now that these same problems on an HD content medium would be an epic bummer for me.

Art
 

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Discussion Starter · #10 ·
Art, I would, too! I would relate it to a 'digital laser disc' of trends. I would most certainly go for a larger DVD disc than go back to magnetic tape. Albeit, D-VHS is backwards compatible with analog VHS, how many of us are still maintaining, or wishing to still maintain, libraries of magnetic tape?


Also, I would be quite happy with a thicker disc that's, say, 10" in diameter to insure non-warping while maintaining the ability to play existing DVD libraries on the same unit. D-VHS would require a second unit in the equipment bay--not a problem for most, but a second everything comes with that requirement.


Also, there are two other companies (aside from Matsushitsu's Blue-Ray) working on large-capacity 12-cm discs that are more than capable of HD material. Only problem that I see there (Constellation 3D's FMD and InPhase's Holographic DVDs).


Still, I think its more politics than appropriate storage technology. If I were a Hollywood studio, I'd be happier selling a $35-40 HD movie on something that will easily detiorate over a short period of time and that is not attractive to bootlegger than supplying DVD-medium HD movies on something with a shelf-life of +30 years.


Still, the costs of implementation, manufacturing, etc. for a LD-style HD-DVD seems to be more than capable using existing technologies. JVC is already learning that not everyone is willing to fork over $2000 for their tape deck and they already discount it 10% when you buy it from them. But then again, they had to because vendors are discounting it as much as 45% off of MSRP. Tells me that the 'market' is not some gung-ho for D-VHS.
 

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The fact remains though that today it's D-Theater or nothing. It seems that DVD HD is 3 or more years on the horizon (and even then who knows what the quality will be). For that reason, I would trade the ability to chapter skip (afterall, I do tend to watch a movie from start to finish) as well as trade the "extras" which I often don't watch anyway, for a pristine unrivaled quality HD movie.


I also think you guys are really overplaying the "deterioration" aspect of this format. I use DV (digital video) to shoot professionally and I can tell you that I've played some tapes 25+ times with absolutely no deterioration. The DV format (and I'm hoping D-Theater) has tremendous error correction built in. What this means is that dropouts are largely a thing of the past. The error correction does an incredible job of making these old tape anomalies a thing of the past.
 

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Discussion Starter · #12 ·
Ken, I know D-Theater is here and now. I also recognize that the 'Blue Ray' based HD/DVD solution is not tomorrow, but in three years time. The whole point of the thread was to implement existing DVD & MPE-2 technologies that would achieve similar, if not same, storage capacities as D-VHS, yet in a more durable storage medium than magnetic tape. I'm not advocating Blue-Ray, FMD, or Holographic DVD. I'm simply advocating the immediate production of 10" (25cm) DVD players and along with them the prerecorded MPEG-2 movies on 10" discs.


Yes, it would be nice if your DV experiences with tape were reproducible for D-VHS, but then I would have to consider that if that were the case why not simply do away with DVD altogether and starting placing 480p prerecorded materials on DV, D-VHS, or similar magnetic tapes and be done with it?


The arguement swings both ways.
 

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Quote:
Originally posted by WanMan
Ken, I know D-Theater is here and now. I also recognize that the 'Blue Ray' based HD/DVD solution is not tomorrow, but in three years time.
Based on this new article ; we might see HD-DVD's with Blu-Ray technology earlier! Hooray Blu-Ray!
 

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WanMan,

My philosophy is "life is short". Three years is a LONG time in my book. That's 3 years I could be enjoying hi def movies at home. There is also no guarantee the quality of whatever disc based HD format arrives, will be as good as D-Theater. I just don't get as excited about the argument that tape "disintegrates" as much as some others. I think the main argument for discs is instant access and less storage space (I also don't get overly excited about extras). I also subscribe to the theory that if the tape format is a good enough medium for archival purposes for the major studios, it should be good enough to me.


However, with that said, I certainly WOULD like to see the arrival of HD DVD with the same quality as D-Theater. However, on the other hand, if HD DVD comes out and it is not of the same quality as the tape based format, count me OUT!
 

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We've all heard promises of products being available early. Unless I see it myself, it isnt an option. As of now D-VHS is a reality while HD-DVD is a fantasy. The enlarged disc variant is interesting but I believe that the studios will resist this after the relative failure of LD. I wouldn't count on the 3 year time frame to hold out. At this point I have heard of no lab that has grown suitable focusing crystals for blue lasers. The diodes last for approxiamately 8000 hours max. That is short of the 20000 hours for normal consumer sale. Until the purification of the crystals is accomplished blue laser technology is not feasible. Unfortunately, this process takes time. If you have the patience, wait the 3 years or more. I, personally, could never accept a vague time frame for product delivery into the marketplace.
 

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I think you're wrong (or misinformed) about the Blue Laser sources. There are two techniques available for generating the blue light for this type of product. One is solid state laser with direct blue emission. These have been under development for many years. The lifetime is growing, but still has less than 10,000 hours at less than 5mW. This is only sufficient for read-only. BluRay, a recordable format, will use Second Harmonic Generation technology. Basically what they do is use a Lithium Niobate Crystal which is widely available to double the frequency of the laser. I don't think the material has to be any different for blue vs. green emission (but I could be wrong). This will halve the wavelength. BluRay specifies 405nm. I don't think this is an accident since 810nm high power laser diodes have been available for many years. Matsushita (Panasonic) has recently shown this type of SHG laser module for optical pickup use. So, I think all the building blocks are all there, they just need to wrap up the specs and get all the production designs done. Of couse, then they need to do interoperability and reliability testing. 2003 Christmas is *possible* (but not likely) for first gen Japan domestic product, but US won't see it for at least two years IMHO.


- Mike
 

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Here's an idea.. why not a DVD player that can take 2 discs at the same time.. and read both sides simultaneously. This would be almost 60GB of capacity, with an 18Mbit/sec transfer rate, at the current spec. All you'd have to do is stripe the data across discs, so you double the transfer rate. Also why couldn't you have lasers on both sides of the disc reading the top and bottom simultaneously? This way nobody has to flip.


I have no idea if these are technically feasible ideas, just some ideas I had.
 

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Wow mdaire, that article is tantalizing. My first thought is in line with miimura's, that Japan will see the 1st gen in late 03 and we'll get it a year after that. Forceflow I'm not sure how you can describe HD DVD as a fantasy when essentially every major CE mfr is part of the blu-ray working group. I see no format wars coming.


And as for an 8 or 10 inch disc, I guess I'd say: I'd still prefer a 5 inch disc (assuming quality on par with or better than D-VHS) and I believe the mass would too.


And Dylan, several LD players had build in side change mechanisms (the entire head would literally flip over inside the maching) though these players were somewhat tall. But the technology clearly exists. Alternatively, another VERY easy solution already exists: the changer.


TM
 

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Quote:
Originally posted by anthonymoody
Wow mdaire, that article is tantalizing. My first thought is in line with miimura's, that Japan will see the 1st gen in late 03 and we'll get it a year after that. Forceflow I'm not sure how you can describe HD DVD as a fantasy when essentially every major CE mfr is part of the blu-ray working group. I see no format wars coming.

[snip]

And Dylan, several LD players had build in side change mechanisms (the entire head would literally flip over inside the maching) though these players were somewhat tall. But the technology clearly exists. Alternatively, another VERY easy solution already exists: the changer.
I disagree about the format war. There are several key holdouts to the BluRay camp as has been pointed out in several articles like this one at EEtimes . Toshiba is one of the notable holdouts from BluRay in the DVD Forum. The EEtimes article also points out that BluRay will probably only be a recordable format like the DVD[+-]R[W] family of formats. It's less clear what will happen for a mass-produced pre-recorded format. IMHO, they should either stay with DVD standard optics or go all the way to 2 or 4 layer stamped discs optimized for blue laser.


I would also be happy if some of the DVD recordable formats went away and they made a standard for players/ROM drives to be compatible with these recordable/erasable discs like they did with CD-RW. In that case they just said "hey, this disc won't read in most of the players, music or computer ROM, but here's how you do it. It's called Multi-Read" and that was the end of it. Why didn't they just do that for DVD? If they had done it earlier, they would have less of an installed base to worry about. Now it may be too late.


They should also have a standardized way that the title author can tell a changer to jump to the next disc. That way you could encode at as high a rate as you want and the changer would automatically go to the next disc when it reached the end of the first one. Full D-Theater speed of 28.2Mbit/sec is only DVD 2.6x (DVD 1x=1353kByte/sec) so data rate is no problem and striping is not necessary. Also flipping the pickup to the other side is REALLY messy. It would probably triple the cost of the mechanism and make the whole player almost double the height.


- Mike
 

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The only thing about Toshiba re: a possible format war is that they do not control either a hollywood studio (like, say, Sony does) nor do they possess as much market control as Sony or JVC imo. If those two go, tosh will follow imo.


TM
 
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