Blu-ray FAQ

Blu-ray FAQ

Introduction

1.1 What is Blu-ray?


Blu-ray, also known as Blu-ray Disc (BD) is the name of a next-generation optical disc format. The format was developed to enable recording, rewriting and playback of high-definition video (HD).mats including ROM/R/RW. The following formats are part of the Blu-ray Disc specification v1.0:

BD-ROM - read-only format for software, games and movie distribution.
BD-R - recordable format for HDTV recording and PC data storage.
BD-RE - rewritable format for HDTV recording and PC data storage.


1.2 Why the name Blu-ray?


The name Blu-ray is derived from the underlying technology, which utilizes a blue-violet laser to read and write data. The name is a combination of "Blue" and optical ray "Ray". According to the Blu-ray Disc Association, the spelling of "Blu-ray" is not a mistake. The character "e" is intentionally left out because a daily-used term cant be registered as a trademark.


1.3 Who developed Blu-ray?


The Blu-ray Disc format was developed by the Blu-ray Disc Association (BDA), a group of leading consumer electronics and PC companies with more than 90 members from all over the world. The Board of Directors currently consists of:

Dell Inc.
Hewlett Packard Company
Hitachi, Ltd.
LG Electronics Inc.
Matsushita Electric Industrial Co., Ltd.
Mitsubishi Electric Corporation
Pioneer Corporation
Royal Philips Electronics
Samsung Electronics Co., Ltd.
Sharp Corporation
Sony Corporation
TDK Corporation
Thomson Multimedia
Twentieth Century Fox
Walt Disney Pictures



1.4 What Blu-ray formats are planned?


As with conventional CDs and DVDs, Blu-ray plans to provide a wide range of for004.

According to Sony of Americas senior vice president Mike Fidler, products based on the Blu-ray Disc format are not likely to be available in the United States until late 2005 or early 2006. However, LG Electronics has stated that they have plans to introduce a Blu-ray Disc recorder in the United States in the third quarter of 2004.

1.5 How much data can you fit on a Blu-ray Disc?

A single-layer disc can fit 23.3GB, 25GB or 27GB.
A dual-layer disc can fit 46.6GB, 50GB or 54GB.

Theres also research going on to add more layers for 100GB-200GB discs (25GB per layer).


1.6 How much video can you record on a Blu-ray Disc?


Over 2 hours of high-definition television (HDTV) on a 25GB disc.
About 13 hours of standard-definition television (SDTV) on a 25GB disc.



1.7 How fast can you record a Blu-ray Disc?


According to the Blu-ray Disc v1.0 specification, 1x speed will require a 36Mbps data transfer rate, which means it will take about 1 hour and 33 minutes to record 25GB. The Blu-ray Disc Association are currently working on the v2.0 specification, which will support 2x speed to cut the time it takes to copy content from one disc to another in half. In the future, the data transfer rate is expected to be raised to 8x or more.


1.8 What video codecs will Blu-ray support?


The Blu-ray Disc Association (BDA) is still in the process of finalizing the BD-ROM specification, but they have stated that MPEG-4 AVC High Profile (previously called FRExt) and Microsofts VC-1 video codec (the proposed SMPTE standard based on WMV9) will be mandatory. They will also include MPEG-2 support for playback of HDTV recordings and DVDs. The BDA expects the BD-ROM specification to be finished by the end of the year. Please note that this simply means that all Blu-ray players and recorders will have to support playback of these video codecs, it will still be up to the movie studios to decide which video codec(s) they use for their releases.


1.9 What audio codecs will Blu-ray support?


The Blu-ray Disc Association (BDA) still hasnt made a final decision about what audio codecs will be included in the BD-ROM specification, but according to the BDF technical spokesman Richard Doherty, the included audio codecs should offer a significant improvement over the audio formats supported by the current DVD spec. They are currently looking into advanced audio codecs, including lossless codecs.


1.10 Will Blu-ray Discs require a cartridge?


No, the Blu-ray Disc Association (BDA) and TDK has successfully developed a new hard-coating technology that will make the discs even more resistant to scratches and fingerprints than existing DVDs, without requiring a cartridge to protect the discs. This development will enable manufacturers to downsize PC drives and lower their overall media production costs.


1.11 When will I be able to buy a Blu-ray Disc recorder?


Youll probably have to wait until 2005-2006 for Blu-ray recorders to become commonly available. The driving force behind the development of Blu-ray Disc recorders is the need to record HDTV programming and currently the only country where HDTV is well established is Japan. Theres still only two different Blu-ray Disc recorders available to consumers in Japan (the Sony BDZ-S77 and Panasonic DMR-E700BD), but as you can see in our Blu-ray Recorders section, most well-known consumer electronics companies have their own prototype Blu-ray Disc recorder in development, so we expect to see more Blu-ray recorders on the Japanese market during 2 36Mbps 11.08Mbps 11.08Mbps
Video compression MPEG-2
MPEG-4 AVC
VC-1
MPEG-2
MPEG-4 AVC
VC-1
MPEG-2 MPEG-2


1.12 What will a Blu-ray Disc recorder cost?


As with any new technology, the first generation of Blu-ray Disc recorders will be very expensive, but the prices have already begun falling. The Sony BDZ-S77 is currently priced at 222,000 yen ($2,030), while the Panasonic DMR-E700BD is priced at 195,000 yen ($1,783). The discs required to record high-definition video are priced at about 2,700 yen ($25) per disc. The explanation for the high retail price is that the recorder is targetted for businesses and enthusiasts rather than regular consumers.

According to the Blu-ray Disc Association, the overall cost of manufacturing a Blu-ray Disc will in the end be no more expensive than producing a DVD. The reduced injection molding costs offset the additional cost of applying the cover layer and hard coat, while the techniques used for applying the recording layer remain the same. As soon as manufacturers start mass production of blue-laser components, which is expected to begin in 2004, the production costs should fall and eventually be within 10% of DVDs.




Current technology

2.1 Will Blu-ray replace VHS?


Yes, thats the expectation. The Blu-ray Disc recorder represents a major leap forward in video recording technology as it enables recording of high-definition television (HDTV). It also offers a lot of new innovative features not possible with a traditional VCR:



Random access, instantly jump to any spot on the disc

Searching, quickly browse and preview recorded programs in real-time

Create playlists, change the order of recorded programs and edit recorded video

Automatically find an empty space to avoid recording over programs

Simultaneous recording and playback of video (enables Time slip/Chasing playback)

Enhanced interactivity, enables more advanced programs and games

Broadband enabled, access web content, download subtitles and extras

Improved picture, ability to record high-definition television (HDTV)

Improved sound, ability to record surround sound (Dolby Digital, DTS, etc)





2.2 Will Blu-ray replace DVD?


Its still too early to say. In the end its up to the movie studios to decide in what format they release their movies, so they will play a big part in the decision of which format becomes the standard for high-definition movies and the successor to DVD. However, they are still earning good money from sales of DVDs, so they arent in a hurry to adopt a new format for movies. They will probably hold off on introducing movies in high-definition until 2006-2007, as they speculate that the DVD market will continue to grow until then. The only movie studio to publically support any blue-laser based format so far is Columbia TriStar, who has stated that they will release movies in the Blu-ray format.


2.3 Whats the difference between Blu-ray and DVD?


Parameters
BD BD DVD DVD
Storage capacity 25GB 50GB 4.7GB 9.4GB
Number of layers single-layer dual-layer single-layer dual-layer
Laser wavelength 405nm 405nm 650nm 650nm
Numerical aperture (NA) 0.85 0.85 0.60 0.60
Protection layer 0.1mm 0.1mm 0.6mm 0.6mm
Data transfer rate 36Mbps