Blu-ray DVD vs. HD-DVD

Updated 3/24/2011 by SuperMediaStore Staff

Blu-ray Disc and HD DVD Media systems both use the same kind of 405nm wavelength blue-violet laser, but their optics differ in two ways. Since the Blu-ray DVD discs has a tighter track pitch , it can actually hold up more pits on the same size blank disk than a HD DVD disc of the same laser wavelength.


That microscopic difference goes a long way. Longer wavelengths suffer more diffraction, which limits their ability to focus tightly on a surface. But a blue laser's shorter wavelength allows it to read and write data over a much tighter surface area, which in turn allows storage of far more data on a disc that's roughly the same diameter of current DVDs. The benefits for backward compatibility are clear: New players will be able to handle both old and new DVD formats in the same machine (outfitted with both red- and blue-laser diodes)—a major consumer benefit that manufacturers hope will drive unit sales.


But while consumers won't have to worry about obsoleteness when it comes to their old DVD collections, the format war brewing between new Blu-Ray and HD-DVD discs does present an age-old problem that evokes the VHS vs. Beta fiasco of the 1980s. The HD-DVD format—like the VHS format that won out over Beta—could become far more widely available to consumers sooner and at a lower price (at least initially) than Blu-Ray discs. That's because the HD-DVD format utilizes manufacturing techniques very similar to those used for the current generation of DVDs. Translation: Third-party duplication houses won't have to retool their factories significantly to make HD-DVDs a reality. That means that HD-DVD discs likely will be the first to market by at least several months, probably by the end of 2005.


On the other hand, Blu-Ray discs require an entirely new manufacturing process with transition costs borne largely by duplicators (unless Blu-Ray backers devise a subsidy system). That, along with other issues, is expected to delay the introduction of Blu-Ray discs until sometime in 2006, which could hand a major advantage to the HD-DVD format. "In this kind of battle, the guy who is out there first and cheaper is going to be the winner," says Fariborz Ghadar, director for the Center for Global Business Studies at Penn State University. "The more expensive and later one is going to be the loser." (The Blu-Ray camp contends that it will bring manufacturing costs nearly in line with HD-DVD during the next year. Parsons says that HD-DVD's cost advantage will amount to only "pennies" per disc over the Blu-Ray format). Unlike Blu-Ray DVD discs, the blank HD-DVD discs can be manufactured with similar equipment in the same plants that make current DVDs.

So now that you know why Blu-ray technology discs cost more and why Media Markets are all battling on one another, we can get to the really important stuff: the numbers, and who's supporting who.


Capacity
Blu-ray
HD DVD
ROM single layer:
ROM dual layer:
RW single layer:
RW dual layer:
Highest test:
Theoretical limit:
23.3 / 25GB
46.6 / 50GB
23.3 / 25 / 27GB
46.6 / 50 / 54GB
100GB
200GB
Single layer:
Dual layer:
-
-
Highest test:
Theoretical limit:
15GB
30GB
-
-
45GB
60GB

Codecs
Blu-ray
HD DVD
MPEG-2
Microsoft Video Codec 1 (aka VC1, WMV HD, etc.)
H.264 / MPEG-4 AVC
MPEG-2
Microsoft Video Codec 1 (aka VC1, WMV HD, etc.)
H.264 / MPEG-4 AVC

Security
Blu-ray
HD DVD
Mandatory HDCP encrypted output
ROM-Mark watermarking technology
BD dynamic crypto (physical layer)
Advanced Access Content System (AACS)
Mandatory HDCP encrypted output (for HD)
Volume identifier (physical layer)
Advanced Access Content System (AACS)

Other interesting facts

  • Even though Apple sits on the Blu-ray Board of Directors, its DVD Studio Pro software supports authoring HD DVD media.
  • Blu-ray, unlike HD DVD, requires a hard coating on its discs because it’s 0.5m closer to the surface. The polymer coating it uses, called Durabis, was developed by TDK and is supposedly extremely resilient and fingerprint resistant.
  • The Java platform is mandatory on Blu-ray as it’s the standard for menus/multimedia (i.e. all Blu-ray systems must support JVM)
  • Though Microsoft has not officially sided with either format, it has a number of long-standing IP cross-licensing deals with Toshiba. HD DVD systems will run Windows CE; the standard is currently the only next-gen optical standard with announced support in Longhorn, and an HD-DVD version of the Xbox 360 is rumored for the future.
  • The first consumer Blu-ray device in the US market is expected to be the PlayStation 3.

In December, Toshiba and other HD-DVD media backers formed the HD-DVD Promotion Group to promote the format, and to ensure early product launches and subsequent market penetration. Other pros and cons seem to bleed together as both formats offer similar features. For example, while HD-DVD touts the ability to create discs with red-laser standard DVD format on one side and blue-laser HD-DVD standard on the other, a Blu-Ray Disc Association spokeswoman points out that JVC announced in December a disc that allows both standard DVD and Blue-Ray content on a single side of the disc. The Blu-Ray Disk camp has argued that single-sided discs are more consumer friendly. In the vital area of picture quality, both formats also have a difficult time differentiating between one another. As the battle heats up in 2005 and well into 2006, customers will have to decide which format will be the final winner.