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Blue Highways
By Victoria Heiland
We've come a long way since the days of videotapes and laserdiscs played
through low-resolution, big-box CRT TVs. Will DVD be the next casualty as
video delivery technology marches on? High-definition video is slowly, but
surely, becoming an industry standard for both television and movies. Each
year, more and more people buy HDTVs, and most television stations will be
broadcasting in Digital Television (DTV) by the end of 2006.
But DTV and HDTV are nothing without high-definition digital content. And
where is that content coming from? On the content-creation end of the
process, high-definition video production tools are rapidly approaching
the broadcast mainstream. Many Hollywood and independent films are already
shot and delivered, where possible, in HD. While most HD-capable
camcorders sell for more than $50,000 and target electronic news gathering
and other broadcast markets, HDV camcorders from JVC and Sony are bringing
hi-def video into play as a viable videography medium. Soon, an increasing
number of videographers and other digital studio pros will be working with
high-definition media and developing content that's tailor-made for their
clients' HDTV home theaters.
All these signs point clearly to a hi-def future. But we're not there yet,
and there's reason to believe the road to HD will be a rocky one—at least
for those of us who plan to get there using optical discs. As long as
we're still delivering content on shiny discs, we'll need a DVD—or worthy
successor—that can handle hi-def content. Current DVD technology is
ill-suited to HD video delivery for several reasons. Capacity is part of
the problem; at 8.5GB per side (using two data layers), DVDs simply don't
have the storage space to present high-def content in the quantities we're
accustomed to—that is, two-hour movies plus menus and extras. The biggest
limitation is the DVD spec, which confines DVD-Video—the highest-def
format most DVD players can play—to "standard-definition" MPEG-2, which
means 480 lines of horizontal resolution, far less than HD's 720 or 1080.
You can fill a DVD with large quantities of, say, hi-def MPEG-4 AVC or
Windows Media 9, but you can't play it back on a set-top player, and PC
movie playback will do little or nothing to establish DVD in the HD
domain.
But don't count out DVD just yet. New blue-laser technology is making it
possible to store significantly more data on a single 120mm disc, and
companies are scrambling to establish an industry standard for blue laser
media. Blue laser-based consumer players are also on the way, with
higher-acuity optics than the red lasers in current players, their
wavelengths matched to blue-laser media's narrower grooves.
As with VHS vs. Betamax and DVD-R vs. DVD+R, two technologies are
competing: HD-DVD (backed by the NEC, Sanyo, and Toshiba) and Blu-ray
(backed by Sony, Pioneer, Panasonic, and others). Perhaps the strongest
parallel to the present HD-DVD and Blu-ray conflict is found in the
prehistoric days of DVD, when Sony/Philips' Multimedia CD (MMCD) vied with
Super Disc (SD) from Hitachi, Matsushita et al. to see whose vision of DVD
would make it to market. Ultimately, the two camps compromised on a hybrid
format that became DVD. (We should be so lucky with HD.)
No such compromise happened with DVD-R/RW and DVD+R/RW, of course; several
years on in the saga of writable DVD, both formats remain distinct (though
they both tend to be found in the same drives nowadays). It's anyone's
guess, at this point, which direction the road to blue-laser DVD will
take—whether proponents of the competing formats will reach a pre-release
compromise or force the public to decide. With players supporting each
format now shipping in Japan, signs currently point to both formats
coexisting, at least for awhile. The same technology giants who brought us
DVD are also key players in HD-DVD and Blu-ray, but it's interesting to
note that alliances have shifted from those established during the DVD±R/RW
format war. For example, Sony and Pioneer, leading proponents of DVD+R and
DVD-R, respectively, now find themselves on the same side.
Another interesting question is which camp Hollywood will support. Video
is just one type of content that blue-laser media will
deliver—technically, the "HD" part refers to the discs' high-density
storage capacity, not their ability to store high-definition video—but
it's video that drives manufacturing, sales, and general acceptance of the
format. Beta did not last long as a viable format once VHS became the
mass-production choice of the movie industry. Many argue that VHS won out,
in fact, because cheaper camcorders made it the format of choice in the
straight-to-video porn industry, just as home video changed the stakes in
that game. It's encouraging to imagine that whichever camp wins the race
to desktop recordability—and thus wins the hearts of videographers—will
triumph in the blue-laser DVD space. But given that big-budget,
high-definition video will initially drive interest in HD-capable DVD
formats, odds are the first content providers that can mass-produce video
in that format—the major movie studios—will draw consumers to whichever
format they choose.
Many factors will affect that choice, and thus where the road to blue
laser actually leads. One is capacity. Another is recordability. But the
key factors, initially, will be manufacturing costs for players and media
(and how much new equipment is required for manufacturing), and how each
camp crafts the logical format that will succeed and determine how video
will be delivered on the blue-laser discs they propose.
The Two Camps
HD-DVD's supporters number 47 companies, including NEC, Toshiba, Sanyo,
and, officially, the DVD Forum, although the Forum's "endorsement" is
hardly what it at first seems. For one thing, many key companies in the
DVD Forum are also in the Blu-ray camp (another reason the red laser
DVD-era distinctions don't apply to blue-laser specs). What's more, the
Forum's approval so far only includes some HD-DVD standards.
Microsoft, likewise, has announced HD-DVD support in the long-delayed
Longhorn OS, but that's hardly an exclusive statement of allegiance. After
all, Microsoft announced DVD+RW support some years back, and that hasn't
had the slightest effect on the format's use on the platform—or the disuse
of competing formats, for that matter. More significant is the adoption of
Windows Media VC-9 in both publishing specs (see below), and Microsoft
opening the codec for HD developers.
The Blu-ray Disc Association (BDA) consists of 70+ companies, among them
Dell, Hewlett-Packard, Hitachi, LG, Mitsubishi, Panasonic (Matsushita),
Pioneer, Philips, Samsung, Sharp, Sony, TDK, Thomson, 20th Century Fox,
and JVC.
With a somewhat broader support base—including, significantly, 20th
Century Fox, the first movie studio to take a side (if you don't count
Sony, which you should, especially since they recently bought MGM)—Blu-ray
appears to have the upper hand. Sony's involvement also means Playstation
3 will go the Blu-ray way. This does not mean that HD-DVD is out of the
race, any more than the DVD Forum throwing some of their weight behind
HD-DVD eliminated Blu-ray. We may end up with two choices, just as we have
DVD-R and DVD+R now. Both formats will specify drives and players capable
of playing back current DVDs as shown in devices demo'd at CEATEC 2004,
Japan's leading consumer electronics show. Both formats will also include
recordable and rewritable versions.
Logical Specs and Publishing Formats
One of the key issues in this debate is what video and audio codecs will
be supported in the publishing formats and why. DVD-Video has always been
a single video-codec format, focused almost exclusively on MPEG-2 (MPEG-1
is in there somewhere, but rarely used in mainstream DVD production or
playback). The DVD-Video spec includes multiple audio codecs, such as
Dolby and DTS, as well as stereo and surround options. While MPEG-2 audio
also is included in the spec, it's not universally supported by DVD
players, which is where things get more complicated. When the two
blue-laser camps support more video formats—and both have already
announced video format support that's broader than DVD's—video producers
will have more options in how they encode and deliver their content, but
may also have to contend with the possibility that some players might not
support all the formats included in the spec. Content creators should also
be aware of their audio format and compression data rate options, which
will be multiple—a definite boon to bit budgeters. The perfect combination
of all three can make or break the perfect video.
HD-DVD has three mandatory video codecs for playback devices: MPEG-2;
MPEG-4, Part 10 AVC (advanced video codec, previously called FRExt); and a
scalable-to-HD Windows Media variation called VC-9. Any of these can be
used by the content provider. The mandatory audio formats for HD-DVD
playback devices are Dolby Digital Plus (DD++), DTS++ (lossy part only),
and Meridian Lossless 2ch (MLP), plus optional DTS++ (lossless part). In
late October, DTS rebranded DTS++ as DTS-HD to make explicit its
connection with both high-definition media formats. According to a DTS
press release, "The DTS-HD mark will denote media, source players and
decoders that are compliant with the next generation high definition disc
formats, Blu-ray Disc and High Definition DVD (HD-DVD)."
The scalability of the video codecs (particularly MPEG-4 and VC-9) will
enable the HD-DVD discs to deliver higher-quality video at lower bit rates
than DVD. According to Toshiba corporate senior VP and DVD Forum chair
Hisashi Yamada, for compression data rates, "7-12Mbps is enough to produce
sufficient-quality pictures for movie material. This is a fixed-rate
coding result. Variable rate coding will provide about 30-50% reduction of
bit rate."
The Blu-ray spec includes the same mandatory video codecs for playback and
recorder devices: MPEG-2, MPEG-4 AVC, and VC-9. It also includes DTS (lossy
part only) as a mandatory audio format, but neither of these lists, along
with compression data rate values, has been finalized. Blu-ray expects to
have the final specification for BD-ROM by the end of 2004.
Physical Specs
Another key issue is the physical makeup of the forthcoming blue-laser
discs. The physical specifications, such as disc composition, track pitch,
and capacity, will determine not only the manufacturing requirements, but
also the design of the equipment needed to play the discs. The physical
composition of the blue-laser discs is hard to exactly define since
neither camp has either finalized or released specific information about
disc composition. While Sony has been selling cartridged Professional Disc
for DATA (PDD) blue-laser discs in Japan, they're not technologically the
same as the BD-ROM discs that we'll eventually think of as the consumer
Blu-ray format. We do know that HD-DVD will be closer to the composition
of a DVD, using a 0.6mm disc with a 0.6mm protective coat. Blu-ray is
stepping away from the DVD norm by using a 1.1mm disc with only a 0.1mm
protective coat (same overall thickness, but differently distributed). The
smaller protection coat gives the laser less material to read through,
allowing a higher numerical aperture and therefore more storage, but it
also could make it easier to damage the disc.
For a current DVD, the track pitch is 0.74 microns (µm). Both Blu-ray and
HD-DVD improve this almost by half: Blu-ray to 0.32µm and HD-DVD to 0.4µm.
They also more than double the storage space of a DVD. For a single-sided,
single-layer DVD, the capacity is 4.7GB. HD-DVD improves this to 15GB, and
Blu-ray offers 25GB. Both formats are dual-layer capable, bringing
per-side capacity up to 30GB for HD-DVD and 50GB for Blu-ray. "This is, in
my view, the single most important consideration, as…creative people will
always manage to fill up available space," says Pioneer SVP of advanced
product development Andy Parsons. "Once we define the maximum capacity of
a high-definition format, it's pretty much set in stone." With 25GB, you
can record approximately two hours and fifteen minutes of high-definition
video, and about 13 hours of standard definition.
Manufacturing
One key factor in the race to establish the preeminent blue-laser format
will be who can bring down manufacturing costs fastest, and accomplish the
most with the fewest modifications to existing equipment and the smallest
investment in new manufacturing lines. Inevitably, some changes are going
to have to be made in how the media is manufactured. The change in
composition, track pitch, and width of laser used all combine to create a
product radically different from DVD. So what changes will have to be made
to current equipment?
According to Toshiba's Yamada, "We already established the process for
HD-DVD this year. This new line can make both HD-DVD and current DVD in
the same line, using the current DVD manufacturing line with small
modification of process parameters but no mechanical change required." The
new line will benefit ongoing standard-def DVD production efforts as well,
he says. "The new manufacturing line can provide better process control
and better quality and yield for current DVD manufacturing."
The biggest change current manufacturing equipment needs to make for Blu-ray
discs will be adding equipment for the cover layer portion. As for the
question of whether existing lines will be tweaked to handle Blu-ray or if
new lines will be installed, by and large, Sony DADC director of
engineering Ed Gehrich says, replicators "will use existing DVD equipment
unless it's being used for DVD product." Sony DADC has been and continues
to work closely with Blu-ray engineers to develop specifications for
replicated blue laser media. Single-layer line-process definition for
replication is complete, but is only available for demonstration at this
point. The recordable line has been on the market in Japan for over a
year, albeit in a somewhat different form, the cartridge-only Professional
Disc for DATA (PDD).
Authoring Tools
So you've shot some beautiful high-definition video and determined that
Blu-ray or HD-DVD is the right medium to store and deliver it, but you're
not out of the woods yet. As in the pioneering days of DVD creation, will
you need to learn a new authoring system to put it all together? According
to Sonic Solutions chief of DVD technology Jim Taylor, "The biggest change
is encoding, using high-definition video and new encoding formats: MPEG-2
HD, VC-9, and H.264." Sony announced its new hardware HD Encoder
(appropriately, a successor to its high-end SD Encoder series) in summer
2004. "The basic specifications are not significantly different," Taylor
continues, "other than higher-resolution subpictures, graphic overlays,
and similar improvements. User interface functionality, asset
manipulation, and workflow control won't change much."
Toshiba, which demonstrated an HD-DVD recorder in July, has much the same
view: "We want to keep the same authoring environment, therefore user
interface will not be changed," says Yamada. "However, codecs and other
new features to be introduced to HD-DVD require additional modification."
Toshiba only supports the HD-DVD format, as befits a recording/playback
hardware manufacturer at this stage of the game, but authoring system
provider Sonic Solutions supports both the HD-DVD format and the Blu-ray
format for its authoring tools. In fact, "Sonic has been actively involved
in advanced interactivity specification development for over three years,"
Taylor says. So if you're already working with Sonic tools—and we can
reasonably expect other authoring solution providers to follow suit as
hi-def DVD authoring trickles down from the Hollywood level—you won't have
to learn a totally new system to be able to author hi-def DVDs, whatever
the format. Learning the advanced features may take more time, however.
"The advanced interactive specifications will be much more complex,
involving more sophisticated preparation of assets and programming,"
Taylor says. "The main difference is that the advanced feature set will
now be available in all next-generation DVD players, not just DVD PCs." An
increase in the complexity of the advance features means that the studio
pros will have to work closer to the spec than they have grown accustomed
to in recent years—as a mature DVD market has given way to more powerful
abstracted tools—but it will also give them more control over the final
product.
Release Dates
"Early versions of blue-laser authoring tools will probably be available
around the middle of 2005," says Sonic's Taylor. "More advanced
interactive application specifications are under development by both the
DVD Forum and the BDA. Authoring tools for these advanced formats will
appear later in 2005 or early 2006." This timeline is very close to the
expected release dates for Blu-ray and HD-DVD.
According to a current press release, the BDA expects to have "BD-ROM
players, drives, and prerecorded software to consumers beginning late
2005." The model available in Japan right now, PDD is for the high-end
market, designed as a storage back-end for the broadcast industry. PDD
player/recorders have an MSRP around $4,000. It was also only designed to
record incoming HDTV and standard definition broadcasts only. It is not
expected that this particular model will become available internationally.
Prices for international models have not been released as of publication
date.
As mentioned earlier, Toshiba demo'd a set-top HD-DVD recorder in summer
2004, but that's far from a shipping product. Toshiba also recently
announced that they expect to ship HD-DVD-equipped laptops in Q4 2005.
Manufacturers in the HD-DVD camp expect to release the first consumer
HD-DVD players in late 2005 as well. The initial retail price for these
players is expected to be $999. They aim to lower the price to about $500
after the sale of 1 million units, which is expected to happen by the end
of 2006.
The Road to Blue-Laser DVD
Shooting high-definition footage, or broadcasting a movie over cable
television in high-definition is great, but without the media to create
discs that will play back in the same quality, both become a one-shot
deal. The footage could possibly be viewed on a computer, but if the rise
of optical disc technology in the last two decades has proven anything,
it's the enormous utility of removable media, and the public's demand for
shiny 120mm discs bearing digital content.
Blu-ray and HD-DVD offer two discrete but similar solutions to this
problem. Both have strong backing—the DVD Forum and the BDA. Both camps
agree that more storage is needed than what DVDs currently offer, but the
BDA believes that maximizing storage upon the format's initial release is
more important than staying close to current DVD specifications. The
HD-DVD camp believes that leveraging current manufacturing equipment as
much as possible will provide a smooth and cost-efficient transition from
DVD that outweighs the storage boost in the Blu-ray spec.
The decision as to which format we eventually end up with may not be up to
the consumer, or the videographer, the DVD author, or even the media,
drive, authoring solution, and equipment manufacturers who comprise what
we think of as the DVD industry. If the movie industry agrees on one
format, and directs all hi-def DVD production toward that format, then
that's what we'll see on the retail shelves, and that what will play and
burn in our drives.
No matter which format is chosen, or if both formats survive, the
high-definition era will soon be upon us. All of our broadcasts and movies
will be available in high-definition, and we will be able to store and
replay these images in their original quality. And it's a sure bet that
one blue-laser format or another will play a crucial role in carrying the
digital studio into the HD era.
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