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Blu-ray

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Blu-ray is a high definition DVD format developed by Sony, and is in competition with Toshiba/NEC's rival HD DVD format. Please refer to The High Definition DVD FAQ for more information on Blu-ray, and the The Blu-ray and HD DVD Buyer's Guide for more practical advice on Blu-ray shopping.

On 19 February 2008, Toshiba announced the end of support for the HD DVD format, thus ensuring Blu-ray will be the victorious format in the Western HD format war.


Contents

Why choose Blu-ray?

Here is a (somewhat subjective) list of reason why one might choose to support Blu-ray (please note that due to HD DVD's capitulation in the HD format war, choosing Blu-ray is now the only choice available):

  • Has studio support from a few of the biggest studios that have a huge catalogue of titles. The big ones include 20th Century Fox, Disney/Buena Vista MGM, Sony Pictures, Columbia/Tri-Stars, Warner Bros
  • Has the support of IT heavyweights such as Apple and Dell
  • Has the support of electronic manufacturers such as Pioneer, Panasonic, and of course, Sony
  • Some Blockbusters stores will only feature Blu-ray rentals
  • The PS3 supports it, so lots of people will have a Blu-ray player
  • Each layer on a Blu-ray disc holds 10 GB than the HD DVD equivalent


Why not choose Blu-ray?

Here is a list of reasons why you might not want to support Blu-ray (please note that due to HD DVD's capitulation in the HD format war, choosing Blu-ray is now the only choice available)::

  • High cost of hardware as compared to HD DVD, unless you already intend to buy a PS3
  • Region coding - Blu-ray has 3 region codes (A, B, C) and it will prevent parallel imports (for example, buying US discs from Australia to save money due to exchange rates is not possible). Note that for the PC, there are now some region-free solutions
  • Excessive copy protection ... not only does it include AACS like HD DVD, it also adds ROM Mark and BD+
  • Specifications not finalized yet, meaning future Blu-ray discs may have features that won't work on current players sold. Specifically, features already present on HD DVD movies like Picture-in-Picture and Internet based content might not be possible on currently sold Blu-ray players. Look for players that support Profile 2.0 features to avoid future problems.
  • Hardware profiles are complicated and this makes it harder for studios to produce advanced content that will work across all three profiles without compatibility problems


Industry Backers

Due to HD DVD's capitulation in the HD format war, technically all companies are now backers of Blu-ray. The list below, thus, is retained here for legacy purposes to provide information on the original backers of Blu-ray prior to Toshiba's announcement to withdraw from HD DVD development.

These backers back the Blu-ray format exclusively in the HD format war, meaning they will not support HD DVD in terms of software or hardware:

  • Sony
  • Apple
  • Dell
  • Panasonic
  • Philips
  • Pioneer
  • Sharp
  • TDK

There are also supporters of Blu-ray that also support HD DVD , and they include Hitachi Maxell, LG, Lite On, Onkyo, Meridan, Samsung, and Alpine.


Movie Studio Backers

See the comprehensive listing at High Definition Studios

Gaming Support

Sony's PlayStation 3 includes a built-in Blu-ray player, and it is currently the most sold Blu-ray player on the market.


Hardware Profiles

There are four profiles for hardware based Blu-ray players, three of them for video based Blu-ray players. Profile 1.0 is known as the "Grace Period Profile". Profile 1.1 is known as the "Final Standard Profile". Profile 2.0 is the "BD-Live" profile, while 3.0 refers to audio only Blu-ray.

Profile 1.0 is used by the first generation of Blu-ray players, but notably lacks a secondard video processor (needed for Picture-in-Picture content) and only requires 64 KB of Persistent Storage. Internet connectivity is also not required.

Profile 1.1 adds the requirement for a secondary video and audio processors, requires 256 MB of persistent storage. All players manufactured after October 31 2007 must comply with this profile.

Profile 2.0 adds network connectivity to the list of requirements, and persistent storage requirement is increased to 1 GB.

All profiles, apart from Profile 3.0 (audio-only) requires support for BD-J.

Table of Blu-ray hardware profiles
1.0 1.1 2.0
BD-J

Yes

Yes

Yes

Secondary Video Processor

No

Yes

Yes

Secondary Audio Processor

No

Yes

Yes

Persistent Storage (minimum)

64 KB

256 MB

1 GB

Network Connectivity

No

No

Yes


Technical Details

Blu-ray Specifications
Laser Type: Blue-violet laser
Laser Wavelength: 405nm
Track Pitch: 0.32µm
Read Power: 0.35mW
Disc size: 120mm
Capacity:
    Single Layer: 25GB
    Dual Layer: 50GB
Transfer Rate: 1x => 36 Mbps
Video Resolution: 1080i (1920x1080 HD, 50i, 60i)
1080p (1920x1080 HD, 24p)
720p (1280x720, 50p, 60p, 24p)
SD (720x576/480, 50i, 60i)
Video Compression: MPEG-2
MPEG-4 AVC
Microsoft VC-1
Audio Resolution/Compression: Dolby Digital AC3
DTS
Linear PCM (uncompressed)
Optional: Dolby Digital Plus (DD+)
Optional: Dolby TrueHD (lossless)
Optional: DTS-HD High Resolution Audio (lossless)
Optional: DTS-HD Master Audio
Copy Protection AACS
ROM Mark
BD+
File System: DF 2.6


See Also

External Link