The Pluses and Minuses of VR and DVD
Posted Aug 1, 2003

DVD authoring software manufacturers are pushing hard to replace the VCR with the -VR and +VR and OpenDVD formats. But if both these formats serve more or less the same purpose, why have more than one?

It's still alphabet city in DVD authoring land, as content providers and end-users—already baffled by the +/-R/RW format wars and their recent, no less baffling detente—try to sort out the differences between +/-VR and OpenDVD. These formats are designed to give users a method of recording and editing that will allow rewritable DVD to replace VHS as an all-purpose re-usable and appendable video recording medium. No longer will a new DVD need to be burned if the user wants to edit content. Sounds simple enough, and it would be if things were standardized around a single format. But, as has always been the case with writable DVD, no such luck. Users must contend with multiple formats and media, as well as different physical and logical writing methods.

Originally designed to provide more flexible and fluid writability and rewritability in set-top, TV-attached DVD recorders, DVD-VR was the first format to emerge. DVD-VR enabled a recorder to write video to disc in real time, a feat that was impossible to achieve under the DVD-Video spec. Before DVD-VR, to write a playable DVD, parameters and navigational information for the complete set of video objects to be included on the disc had to be set before writing began. Because that information is unknown as new video is streamed, recording video to DVD "live" in DVD-Video-compliant fashion was impossible. DVD-VR supplied alternative ways to incorporate that information. DVD-VR also allowed users to edit recorded video, delete unwanted segments, and modify and customize playlists. At the time of DVD-VR's debut, desktop DVD recording was primarily a professional author's medium, used for making check-discs to test compliance and playability before sending a disc for replication, and DVD-R was the only game in town. So the kind of applications DVD-VR made possible weren't really relevant to desktop DVD recording as it was then defined.

The intervening years have brought not only additional formats—DVD-RW, a rewritable extension of DVD-R, and two competing standards, DVD+R and DVD+RW—but also a broad base of home and home office users to DVD recording, and with them a broader range of applications and expectations. With this expanded user base comes, the DVD+RW camp in particular believes, the expectation that desktop DVD recorders, like their set-top counterparts, should also offer the facile rewritability of VCRs. Enter DVD+VR, a video recording format analogous to -VR, but designed specifically for use with plus-format drives. Enter as well OpenDVD, a writing method designed by DVD authoring software market leader Sonic Solutions for use with their ubiquitous entry-level authoring tool, MyDVD.

And then there were three. And as with all these multi-format DVD debates, beyond the relative advantages and disadvantages of each format, a nagging, underlying question always seems to linger: If all these formats serve more or less the same purpose, why have more than one? But since that's not up to us as users (especially since the recent profusion of "multi-family" drives means users will never really get the chance to choose their favorite), a more relevant question emerges in the migration of these "application formats" from TV to PC: Do they really belong anywhere but the living room? What can these formats (the VRs, anyway), designed to compensate for the shortcomings of TV-attached recorders, possibly do for the PC recording space, which doesn't share the same handicaps?

Inevitably, the answer for each format is slightly different. So let's begin with a look at each format and its pros and cons.

VR So Far
DVD-VR, described by the DVD Forum as an "application format," is a logical format specifying how discs are recorded. The DVD Forum approved the DVD-VR spec for DVD-R/-RW or DVD-RAM/R video recorders in 2000. More recently, a functionally similar format designed for an entirely different set of recorders, DVD+VR, has emerged. DVD+VR has not been approved by the Forum, but rather by the DVD+RW Alliance, which means it has separate but equal (or perhaps even greater) manufacturer support. DVD+VR is designed exclusively for use with DVD+R/+RW recorders. Then, to throw a real wrench into the works, there's Sonic's OpenDVD, which works only with Sonic's proprietary software, including both retail and bundled versions of MyDVD and other applications that incorporate the Sonic authoring engine.

The original DVD-Video spec did not focus on re-recordables. According to Jim Taylor, author of DVD Demystified and chief of DVD technology and general manager of the advanced technology group at Sonic Solutions, "All of the thinking that went into the DVD-Video spec was based on the concept that a disc would be created through this long process with plenty of time to format the disc." That works fine for Hollywood, but not for real-time recording. Says Philippa Hare, corporate and product marketing at MedioStream (whose neoDVD competes directly with Sonic's MyDVD), "Consumers are looking for faster computers, faster Internet connections, faster everything. Following that thread, they aren't going to want to wait a long time for their DVD to be recorded. VR capability reduces dramatically the DVD creation time."

Another problem with the original format is that it allowed no way to revise a disc. While a finished Hollywood disc never changes, it's possible that a desktop or set-top user working in a small studio or at home may want to change the disc. But as it stands now, says Taylor, "They can't redo menus because they have been composited together into a single graphic."

-VR Versus +VR
The "dash" and "plus" VR formats were designed for consumer electronics (CE) devices rather than PCs. Because set-top (CE) DVD recorders have a lower aptitude for project data retention and re-use than PCs, navigational data on a VR disc, once a disc is appended, edited, or otherwise altered, is not always preserved. For example, adding a video clip to a +VR disc often causes the menus to be recreated from scratch. And, in most cases, any extra data in the ROM zone (original photos, personal files, HTML pages, etc.) is deleted, according to Taylor.

Ulead Systems, maker of DVD MovieFactory, which competes with Sonic's MyDVD, disputes the relevance of Taylor's statement to PC-authored discs. "It is true that a Philips set-top recorder will rewrite the menu area and put a default menu in place every time some data is added to a disc with existing content on it," says an engineer interviewed at Ulead. But DVD MovieFactory, he says, "preserves the existing menu layout and configuration depending on the operations performed during the re-edit or recording session." The user can then elect to modify the menus in each editing session with MovieFactory or delete them if they so desire.

DVD MovieFactory also disables the archiving feature for +VR discs to avoid the problem of ROM material being deleted. However, extra video can be archived with extra data. To be able to archive data when working with the +VR format, a user can copy the +VR format to a standard DVD-Video format and then include the archive data on the DVD-Video disc.

For basic disc editing in a low-end consumer player, the -VR and +VR formats are well-suited, since they are optimized for those players' limited memory, limited processing power, and lack of a hard disk drive.

-VR borrowed a lot from the data format with the way video objects are stored on the disc. However, the Forum re-did the access information to handle real-time recording and did away with on-disc menus so the player itself generates the menus. "It's designed very specifically for consumer-level real-time recording, but it's not compatible with the DVD-Video format. My rough calculation is that it works on less than one percent of the players out there," says Taylor.

A standard exists for -VR, but it is not in the hardware. "It all has to be done through software, which is one of the reasons why you see some companies advertising +VR capability instead -VR. It's really hard to do," says Bob DeMoulin, marketing manager for branded storage products in Sony Electronics' IT products division.

The +VR Alliance approached things from the compatibility standpoint right from the beginning. The +VR format is a set of constraints on the DVD-Video specifications that allow it to work in a real-time recording environment. "+VR plays a bunch of tricks with the format and comes up with a way to record in DVD-Video format in real time on a set-top recorder," says Taylor. The advantage is that a DVD-Video disc will be created that will play in 99 percent of the playback devices.

The tradeoff is that +VR is not as flexible as -VR. For example, a moving menu can't be created because there isn't enough memory. Which format is chosen depends on what the consumer is looking for. -VR is slightly less visual. When a +VR disc is recorded, the user creates thumbnails. Hare offers a scenario using a disc containing episodes of a weekly television show. "The first page would show six episodes you can watch. You can then build additional pages. If you've got 12 episodes, you can have six more thumbnails on the next page. What you see is the first frame of the video, and you can give it a title. The overall page also has a title." With the -VR format, only a playlist is generated; no thumbnail is possible.

Opening Another Can of Worms
Sonic Solutions' OpenDVD addresses the issue of consumer-style DVD rewritability from a different angle; first and foremost, it's unique among the three in being the only one originally designed, rather than awkwardly adapted onto, the PC-based recording process. But it's also functionally different. The primary reasons to use OpenDVD are to preserve information and provide portability. OpenDVD is appropriate for output on low-end CE devices in order to preserve information on the disc, but full use of OpenDVD for revising and updating discs is only possible on computers or high-end CE devices. [

VR and +VR are not compatible with each other, but OpenDVD is compatible with both. While compatibility issues are being dealt with and will not likely be a problem in the future with new players, there are still 56 million DVD players in the U.S. market already. Not only will consumers want to share discs with family and friends, they may be sharing within the same household, Jim Taylor argues. Those 56 million players are only in 42-43 million households, which means that many households already have more than one player, which means some houses may be divided against themselves, DVD compatibility-wise. "As we get more and more recorders, people are going to buy their second home recorder. They're going to take their old DVD player and move it into another room, and they're going to want to make discs that they can play in any player in the house with no problem. That is a key component of the compatibility issue," says Taylor.

But the primary advantage of OpenDVD, according to Sonic, is an ease-of-appendability that accommodates the potential complexity of PC-authored discs. By preserving all project information on the disc (though not the original source video files; you'll still need to have those stored in the same location), users need only to re-insert the recorded disc in their PC to access the project from which it was created. This feature is analogous to +/-VR in the sense that it makes disc-editing easier (by enabling users to build on existing work rather than starting over), but it's more tailored to the way discs are authored on a PC. "If someone spends time customizing their disc," says Taylor, "they don't want to lose that information if they add something to the disc or make other changes to the disc. Or if video is transferred from digital video tapes to DVD, you'd like the metadata (date recorded, camcorder settings, stop/start points, etc.) to be preserved. OpenDVD accommodates all of this."

What's The Benefit And Should We Care?
After all that is explained, the question is: "Will the user really care?" In a way, this gets to the heart of the question that all technology providers have to ask, even if the answers they come up with are largely speculative: "How will people really use this stuff?" One saving grace of the format war, or at least some justification for its persistence, is that the opposing camps don't just have products competing for profits and market shares—they have genuinely opposed views of what end-users want out of DVD recorders, and what they will want to see in the products they buy based on those preferences.

The DVD+RW Alliance believes rewritability is the essential feature of DVD recorders, both set-top and desktop; the DVD-R camp believes users prefer write-once. The DVD+RW Alliance believes the convergence of PC and CE, as it applies to writable DVD, means not only that discs recorded in the drives should play in CE environments, but that PC and CE recorders should perform and be used in similar fashions. In other words, that PC DVD recorders, like their CE counterparts, should ape VCRs as much as possible when used to record video. The DVD-R camp, conversely, believes PC recorders and CE recorders are things apart.

Andy Parsons, senior vice president of business solutions at Pioneer, says VR is not a major feature for computer drives. -VR can be thought of as a simplified version of DVD-Video, and its primary purpose is to accommodate off-air TV recording. +VR is a "redesigned version of DVD-Video that the +RW camp developed to accommodate their method of recording +R/RW discs in video recorders." These are not necessary features, he argues; "Software provided with a lot of the drives will allow you to do the same things."

Panasonic, on the other hand (whose -RAM format and -RAM/R/RW MultiWrite drives also have the DVD Forum's backing), believes strongly that there is a major interest in VR for consumer DVD recording. In June, the company released results of a survey conducted by IDC (and sponsored by Panasonic), which says consumers are expected to purchase some 16 million standalone and PC-attached DVD recorders in 2003, a near-threefold increase over 2002. Sales, it says, will be fueled by attractive pricing and a host of new features such as simultaneous play/record and on-disc editing.

Among its key findings, the study showed that consumers clearly view DVD recording as a video application, and expressed overwhelming preference for standalone units over a PC-attached device. This held true, according to IDC's study, even for the purchase of a second unit. Additionally, more than 80 percent of respondents felt they would view self-recorded DVD discs in their living rooms.

When ranking the importance of several DVD recorder product features and functions that influence purchase, 82 percent of respondents listed worry-free recording as the top feature, followed closely by compatibility with other players (80 percent). However, the report's findings did not indicate a desire for +/-VR capability in PC-based drives, although that type of functionality clearly holds sway among the survey group.

That said, DeMoulin admits that he has been monitoring Sony's tech support top 10 call list, and has never seen a question about VR (plus or dash). "That's probably because they don't know they can do it," he says. "Right now, people look at burning DVDs the same way as they look at burning CDs—you burn it, it's burned."

MedioStream's Hare offers a practical analogy to illustrate the benefit of VR and perhaps the message that needs to get to consumers so they will understand the format in layman's terms. "When you have a baby, you want to track its development," says Hare. "Wouldn't it be cool if you didn't need a new DVD every time you wanted to add new video footage? DVD now works like a VHS tape, but even better. You can put it in the computer and author it. You can also overwrite what you don't want," Hare continues. As digital camcorders and DVD television recording become more popular, sources say, many expect that VR will enable DVD recorders to become the convergence device between the living room and the office.

Taylor, meanwhile, believes not only that this will happen, but that it should. He's convinced that the need to bring the set top and the PC together is a real one. "In general, anybody who's interested in making very many changes to a disc that they've recorded is not going to want to sit in front of a television with their up-down, left-right remote control and do lots of complex editing," he says. "People who are interested in that may want to record on their set-top player, but when they want to make changes, they'll want to do that on their PC where they have a whole lot more power."


DVD Forum,
DVD+RW Alliance,
Pioneer Electronics,
Sonic Solutions,
Sony Electronics,
Ulead Systems,