Dual Layer Disk Recording Hurdles

[Tearren]

Interesting...


Pioneer reveals some dual layer disk recording hurdles
Posted by Dan Bell on 31 December 2003 - 04:30 - Source: C|Net


While taking a rare break at my workstation this morning, I was in instant messaging range of Joerg Kling of CD Freaks. Good thing, he found an article at C|Net that I had dismissed earlier. It appeared the article was about the ongoing battle between the +/- camps and which is superior, so I didn't read it. Yet, Joerg did and mentioned that within the article were some nuggets of information that might be of interest. Once read, the whole article is very good information for us that are curious about dual layer writing technology.

We will see 2.4x recorders as early as this spring and it seems the plus camp of HP, Phillips and Dell is going to market first. Andy Parsons, senior vice president in the business solutions division of Pioneer Electronics USA and Hans Driessen, global communications manager for Philips' Optical Storage division, made a few statements in the C|Net article that we found very interesting.

Dual-layer recording, no matter what the format, faces hurdles. One is the importance of fully recording both layers of a dual-layer disc, he said. If that doesn't occur, Parsons said, some DVD players might behave unpredictably, for instance by causing a momentary interruption of the program.

Fully recording an 8.5GB dual-layer disc could increase the time needed to make a recording, according to Parsons. "That's what we're thinking about now," he said. "One must be careful not to rush things to market.

The dual-layer DVD+R specification does not require the entire disc to be recorded. Philips' Driessen said that if one layer of a dual-layer DVD+R has a recorded signal at a particular point on the disc, the other layer must have a matching signal; otherwise, a player may detect an error. For example, if one layer has 4GBs of data recorded, the other layer must have 4GB as well. But he said blank space may be left at the edge of the DVD without any playback problems.

Arranging for both layers to be recorded in equal amounts is relatively easy in the case of data files of a known size, Driessen said. When a user records a television broadcast of unknown length, however, the drive may need to add "dummy" data in order for the disc to be readable in DVD players. This could mean a finalization process of up to 25 minutes, Driessen said. "Future write speed improvements (such as 4x) will reduce this finalization time," he said.


The article also delves into other technical and compatability challenges that present themselves with a burner that can write to two layers. DVD's that we purchase with a pre-recorded movie are pressed or stamped to create the pits and lands. Not as complex a task as this new burning hardware faces it seems.

You may want to go C|Net and read the entire article to learn more about this fascinating step in the evolution of optical burners. There is quite a bit of good information that can be gleened from this story. It is amazing the technology that we are about to be presented with. Sometimes, maybe we take it for granted what these engineers must do to bring us such products.


http://www.cdfreaks.com/news/8789

Tearren

[MOVIEGEEK]

Verbatim is scheduled to release 2.4x DVD+R DL media in spring(?).
www.cdrinfo.com/Sections/News/Details.asp?RelatedID=4687

[Faustus]

Verbatim is scheduled to release 2.4x DVD+R DL media in spring(?).
www.cdrinfo.com/Sections/News/Details.asp?RelatedID=4687

That would fit nicely with the April +R DL burner rumor.

[GizmoTheGremlin]

I'm still crossing my fingers that a firmware upgrade will make my burner work with the media. Doubtful, but I'm still hoping.

[triphop]

I'm still crossing my fingers that a firmware upgrade will make my burner work with the media. Doubtful, but I'm still hoping.

Dream on

Feature adding firmware upgrades are really not a good business model although they certainly are a great PR exercise. I was very happy when Sony added features to my DRU500A.

[RabidDog]

Also I think its more than a small exercise to make a single layer drive record dual layer..

IMHO .. they hold out these "Hopes" so that the sales of SL dont dry up b4 DL comes along

[lordsmurf]

Blah blah blah ... show me something concrete. So far, dual-layer is just hoopla and speculation. I want one too, but I'm not holding my breathe just yet.

[dafoe]

I certainly don't want to start another - v + argument. But what about DVD-R?! I prefer this format because I have found it to be more compatible.

Are they even working on a DVD-R drive? It would seem to make more sense given the apparent DL limitations of the + format.

Each layer must match the other layer in size? So much for one click backups. Which, for me at least, is the only selling point of a DL burner.

[Faustus]

I certainly don't want to start another - v + argument. But what about DVD-R?! I prefer this format because I have found it to be more compatible.

Are they even working on a DVD-R drive? It would seem to make more sense given the apparent DL limitations of the + format.

Each layer must match the other layer in size? So much for one click backups. Which, for me at least, is the only selling point of a DL burner.

Yes Pioneer is working on one, but thats basicly all thats known at this point. Its widely assumed that +R DL will come out first.

What you need to consider is that dual layer burning is basicly a new format, so compatibility between the 2 remains to be seen. Either could be the most compatible.

[GizmoTheGremlin]

I'm guessing that overall compatibility is going to take a plunge, at least in how many dvd players will be able to play these discs. I know that it shouldn't, and I hope it doesn't, but I'm just assuming the worst.

As far as -R, from what I've read, I think you'll be lucky if they come out this year.

[Gazorgan]

Everything I've read about Dual Layer indicates it's going to flop. The only practical use if going to be backing up DVD9's.

There are no RW's mentioned.
Initial speed is 2.4x when 8x's are shipping.
For video, upper and lower layers have to match, which means good luck Authoring your own!!!
It will take NERO months to deal with it correctly (insert laugh track here).
Repeat after me: Layer transition hiccups.
If you think settop players are media finicky now, wait until Dual Layer disks are inserted.


I really think the future is in the next standard. That may be blueray, redray, or whatever standard of the 3 wins. We are looking ar 4x densities (which is good, as HDTV is 4x denser). We are also looking at more efficient codecs, so it should all even out.

[bugster]

Everything I've read about Dual Layer indicates it's going to flop. The only practical use if going to be backing up DVD9's.

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What about longer recording times/higher bitrates for standalone DVD writers. Thats where I see these being most likley to be succesful.

[Gazorgan]

According to what the article states, that's going to be a problem. Not for data disks per say, but you will get a layer transition hiccup with a settop DVR.

Higher bitrates? Must have missed that.

[bugster]

Higher bitrates? Must have missed that.

I meant longer recording times at best quality mode when I said that, not that higher than current max bitrates will be available.

So 3 hours at best quality, rather than 90 mins (or whatever).


Hmm, Layer change delay during recording could be an interesting technical problem to overcome

[neomaine]

Look like the Consumer Elec Show has them ready for you to look at:

www.cnn.com/2004/TECH/ptech/01/08/bus2.ptech.gadgets.ces/index.html


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Sony Double-Layer DVD
Sound bite: Hot off the presses, the first of the double-layer DVD drives and discs will ship this quarter. Sony, historically a flagship in digital media storage, will be doing a first-look demo.

Real-world business app: With nearly twice the capacity of standard discs, or about 8.5GB each, double-layer DVDs will no doubt be instantly christened the non plus ultra of digital storage for entertainment-media types. www.sony.com
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