Blu-ray FAQ

Blu-Ray discs are unique in their ability to store up to 25GB on a single-layer disc. When compared, Blu-ray discs have five times the storage capacity than a standard DVD while maintaining the same physical disc size. This showcases the latest advancements in optical disc formats, such as showing disc popup menus that appear over the program content.

Today almost 50 million households in America are HDTV compatible. At USA Discs we have the capability to create as well as distribute any Blu-Ray project to reach your desired audience.

For an incomparable viewer experience, USA Discs uses only the most advanced audio and video codecs of Blu-Ray technology as well as Blu-ray Disc Java (BD-J.) This provides the viewer with enhanced interactive menus and spectacular image and audio quality.

Blu-ray or Blu-ray Disc, are the most advanced optical disc format.  Large amounts of data are now able to be stored on one single Blu-Ray disc. This new technology enables the recording; rewriting and playback of high-definition video. (HD)

The Blu-ray name stems from the blue-violet laser that is used to read and write data to and from the disc.  The letter “e” was purposely left off of the term “Blu-ray” so the term could be registered as a trademark.

The 405 nm (blue) wavelength laser used to read and write information on a Blu-ray Disc created the Blu-ray name. The intentional misspelling by the creators made it a viable name for trademark protection. The general acronym used for Blu-ray Disc is BD.

Here are a few benefits of using Blu-Ray:

• - Up to 1080p HD Video in MPEG-2, VC1 (Windows Media 9) or AVC (H.264) codecs
• - Up to 7.1 surround audio (PCM, Dolby Digital and DTS are supported)
• - Full color menus over video, with animated buttons and highlights
• - Sound effects attached to menu buttons
• - Slide shows with uninterrupted soundtracks

In the spring of 2006 Blu-Ray officially launched and has been gaining in popularity ever since.

Blu-ray authoring is ideal for delivering HD programming to your viewer audience. Currently Blu-ray is supported by more than 180 of the world’s primary consumer electronics, personal computer, recording media, video game and music companies. With so many users world-wide it has become the clear successor to the DVD format.

The answer is HDTV or High Definition Television. With HD, the amount of detail compared to standard-definition (SD) is six times greater. Today's DVDs only support SD and do not have the required storage capacity to satisfy the needs of HD. Blu-ray offers up to 50GB of storage capacity and enables playback, recording and rewriting of HD in all of the HD resolutions including 1080p. The Blu-ray format also supports high-definition audio formats and lossless audio. Viewers can also enjoy additional content and special features with the extra storage capacity.

Blu-ray Disc Format Specifications
	BD-ROM (prerecorded)	BD-R (recordable)	BD-RE (rewritable)	AVCREC (recordable, rewritable)
Physical Format	BD-ROM (Part 1)	BD-R (Part 1)	BD-RE (Part 1)	DVD±R/RW/RAM
File System Format	BD-ROM (Part 2)	BD-R (Part 2)	BD-RE (Part 2)	AVCREC (Part 2)
Application Format	BD-ROM (Part 3)	BD-R (Part 3)	BD-RE (Part 3)	AVCREC (Part 3)

Features	BD-ROM	BD-R	BD-RE	BD9
Type of disc	Prerecorded	Write once	Rewritable	Prerecorded
Data layer type	Molded	Inorganic, dye	Phase-change	Molded
Data layers	1 or 2	1 or 2	1 or 2	1 or 2
Rewrite cycles	NA	NA	1,000 min	NA
Disc diameter	8 cm, 12 cm	8 cm, 12 cm	8 cm, 12 cm	12 cm
User capacity	23.3, 25, 27 GB (12 cm SL) 46.6, 50, 54 GB (12 cm DL) 7.8 GB (8 cm SL) 15.6 GB (8 cm DL)	23.3, 25, 27 GB (12 cm SL) 46.6, 50, 54 GB (12 cm DL) 7.8 GB (8 cm SL) 15.6 GB (8 cm DL)	23.3, 25, 27 GB (12 cm SL) 46.6, 50, 54 GB (12 cm DL) 7.8 GB(8 cm SL) 15.6 GB (8 cm DL)	4.7 GB (SL), 8.5 GB (DL)
Cartridge	Optional	Optional	Optional	No

Blu-ray discs currently come in single layer and dual-layer versions. Eventually, multi-layer (3 or more layer) discs will be supported. For a single layer discs the storage capacity is 25GB, which is more than 5 times the capacity of a single layer DVD. Each additional layer adds an additional 25GB of storage. These two types of discs are often referred to as BD25 and BD50.

Blu-Ray discs support MPEG-2 compression likes those found in DVDs, MPEG-4 AVC and also Microsoft's VC-1 (the exact same set as HD DVD's support).  Most titles are now using the more efficient H.264 or VC-1 codecs.  MPEG-4 AVC, also known as H.264 or MPEG-4 Part 10. H.264 High Profile, is used for the encoding.

The supported mandatory formats are DVD audio formats of Dolby Digital AC3 and DTS. Linear PCM audio is supported up to 7.1 channels. Dolby Digital Plus (DD+), Dolby TrueHD, DTS-HD and DTS-HD Master Audio are all part of the optional specifications.

To watch a Blu-ray disc a viewer would need a Blu-ray disc player. A DVD player which existed prior to Blu-Ray production will not be able to read a Blu-Ray disc, and there is no software or hardware upgrade that can be carried out to enable Blu-Ray disc playback.

The Universal Disc Format (UDF) developed by the Optical Storage Technology Association (OSTA) is specified for most applications, though it is possible for BD discs to employ any number of file systems. UDF version 2.5 applies to BD-ROM/RE and both UDF version 2.5 and 2.6 to BD-R.

Take note that Windows XP, unlike Vista, does not natively support these UDF versions. Therefore, it is essential with XP to install a compatible driver or packet writing software to access the directories and files.

Blu-Ray Discs utilize AACS (Advanced Access Content System) to protect its digital data. Though similar to the flawed CSS used with DVD’s, its "key" difference is in how the various decryption keys are distributed. AES encryption is to be used.

The Blu-ray Disc Association (BDA) develops and licenses Blu-ray Disc technology. Click here for a list of Players and Playback software updates that are currently available.

Blu-ray discs supports the following codecs for HD content: MPEG-2 Main Profile @ High Level; MPEG-4 AVC, part of the MPEG-4 standard known as MPEG-4 Part 10; and SMPTE VC-1, a codec based on Windows Media 9 technology. Additionally, MPEG-2 Main Profile @ Main Level is used for standard definition NTSC or PAL content, same as used in DVD.

The Blu-ray optical disc format stores up to 25GB on a single-layer disc (BD-25) and up to 50GB (BD-50) on a dual-layer disc; translating to up to 9 hours depending number and type of audio streams, subtitle streams, picture angles and video codec/bitrate used.

• - Blu-ray audio codec: Linear PCM (LPCM) - up to 8 channels of uncompressed audio.   (mandatory)
• - Blu-ray audio codec: Dolby Digital (DD) - format used forDVDs, 5.1-channel surround sound.   (mandatory)
• - Blu-ray audio codec: DTS Digital Surround - format used forDVDs, 5.1-channel surround sound.   (mandatory)
• - Blu-ray audio codec: Dolby Digital Plus (DD+) - extension of Dolby Digital, 7.1-channel surround   sound.   (optional)
• - Blu-ray audio codec: Dolby TrueHD - lossless encoding of up to 8 channels of audio. (optional)
• - Blu-ray audio codec: DTS-HD Master Audio - lossless encoding of up to 8 channels of audio.   (optional)
• - Blu-ray audio codec: DTS-HD High Resolution Audio - extension of DTS, 7.1-channel surround   sound. (optional)

Parameters:		Blu-ray	DVD
Storage capacity:		25GB (single-layer) 50GB (dual-layer)	4.7GB (single-layer) 8.5GB (dual-layer)
Laser wavelength:		405nm (blue laser)	650nm (red laser)
Disc diameter:		120mm	120mm
Disc thickness:		1.2mm	1.2mm
Protection layer:		0.1mm	0.6mm
Hard coating:		Yes	No
Data transfer rate (data):		36.0Mbps (1x)	11.08Mbps (1x)
Data transfer rate (video/audio):		54.0Mbps (1.5x)	10.08Mbps (<1x)
Video bit rate (max):		40.0Mbps	9.8Mbps
Video resolution (max):		1920×1080 (1080p)	720×480/720×576 (480i/576i)
Video codecs:		MPEG-2 MPEG-4 AVC SMPTE VC-1	MPEG-1 MPEG-2 --
Audio codecs:		Linear PCM Dolby Digital Dolby Digital Plus Dolby TrueHD DTS Digital Surround DTS-HD Master Audio	Linear PCM Dolby Digital DTS Digital Surround MPEG Audio (.mp2) -- --
Interactivity:		BD-J HDMV	DVD-Video
Track pitch:		0.32µm	0.74µm
Numerical aperture:		0.85	0.6