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Blu-ray and HD-DVD - What You Need To Know

Blu-ray and HD-DVD Basics

By Robert Silva, About.com

Blu-ray Disc Player Trio - Top: LG BH100 - Center: Samsung BD-P1000 - Bottom: Sony BDP-S1

Blu-ray Disc Player Trio - Top: LG BH100 - Center: Samsung BD-P1000 - Bottom: Sony BDP-S1

Photo (c) 2007 - Robert Silva - Licensed to About.com
NOTICE: HD-DVD is now officially discontinued. However, information on HD-DVD, and its comparison to Blu-ray, is still contained in this article for historical purposes, as well as the fact that there are still many HD-DVD player owners, and HD-DVD players and discs will continue to be sold and traded on the secondary market for some time.

The Current State Of DVD

DVD is very successful, and will definitely be around for some time. However as it is implemented, DVD is not a high-definition format. DVD players typically output video in either standard NTSC 480i (720x480 pixels in an interlaced scan format), with progressive scan DVD players capable of outputting DVD video in 480p (720x480 pixels displayed in a progressively scanned format). Although DVD has superior resolution and image quality, when compared to VHS and standard cable television, it is still only half the resolution of HDTV.

Upscaling - Getting More Out Of Standard DVD

In an effort to maximize the quality of DVD for display on today's HDTVs, many manufacturers have introduced upscaling capabilities through DVI and/or HDMI output connections on newer DVD players. Upscaling is a process that mathematically matches the pixel count of the output of the DVD signal to the physical pixel count on an HDTV, which is typically 1280x720 (720p), 1920x1080 (1080i), or 1920x1080p (1080p).

The upscaling process does a good job of matching the upscaled pixel output of a DVD player to the native pixel display resolution of an HDTV, resulting in better detail and color consistency. is currently implemented, upscaling can't convert standard DVD images into true high-definition images.

True High Definition DVD Is Here

Now, both HD-DVD and Blu-ray players are currently available, with units adding recording capability also available in some PCs and Laptops, to be followed, possibly, by Blu-ray recorders available possibly sometime in the future in the U.S. Market. However, as of February 19, 2008, HD-DVD has been discontinued. As a result new players, or the possibility of recorders, in that format, will no longer be available going forward.

Blu-ray and HD-DVD both employ Blue Laser technology (which has a much shorter wavelength than the red laser technology used in current DVD). Blu-ray and HD-DVD enables a disc the size of a current DVD disc (but, which much greater storage capacity than a standard DVD) to hold an entire film at HDTV resolution or allow the consumer to record two hours of high definition video content.

Blu-ray and HD-DVD Format Information

However, there is a catch with regards to high definition DVD recording and playback; up until 2008, there has been two competing formats that were incompatible with each other.

Blu-ray Format Support

Blu-ray is supported on the hardware side by Apple, Denon, Hitachi, LG, Matsushita (Panasonic), Pioneer, Philips, Samsung (also supports HD-DVD), Sharp, Sony, and Thomson (Note: Thomson also supported HD-DVD).

On the software side, Blu-ray is supported by Lions Gate, MGM, Miramax, Twentieth Century Fox, Walt Disney Studios, New Line, and Warner. However, as the result of the discontinuation of HD-DVD, Universal, Paramount, and Dreamworks are now on board with Blu-ray.

HD-DVD Format Support

HD-DVD has been supported on the hardware side by NEC, Onkyo, Samsung (also supports Blu-ray) Sanyo, Thomson (Note: Thomson also supported Blu-ray), and Toshiba.

On the software side, HD-DVD has been supported by BCI, Dreamworks, Paramount Pictures, Studio Canal, and Universal Pictures, and Warner (only until May 2008 - at which time it will be Blu-ray exclusive). Microsoft had also lent its support to HD-DVD, but no longer, as Toshiba has ended HD-DVD support.

NOTE: However, all HD-DVD hardware and software support will be discontinued and shift to Blu-ray by mid-2008.

Basic Specifications Of Blu-ray and HD-DVD

Although both Blu-ray and HD-DVD support both recording and playback of high definition material with the same expected result, there are technical differences between the two formats.

Blu-ray - General Specifications:

Storage Capacity - Pre-recorded Playback Material (BD-ROM): Single-layer (25GB) - Dual-layer (50GB)

Storage Capacity: Home Recording (BD-R/BD-RE): Single-layer (25GB) - Dual-layer (50GB)

Data Transfer Rate: 36 to 48 MBPS (Megabits per Second) average - capable of up to 54 MPS - This exceeds the 19.3 Mbps transfer rate approved for HDTV broadcasts.

Disc Properties: New format requiring retooling and/or construction of new disc manufacturing and replication plants.

Video Specifications: Compatible with full MPEG2 Encoding, as well as MPEG4 and VC1.

Audio Specifications: Only Dolby Digital, DTS, and Uncompressed PCM are required on all players. However, the following formats are optional - Dolby Digital Plus, Dolby TrueHD, DTS-HD.

Network Capability: Although the Blu-ray format supports networking and internet capabilities, built-in networking and ethernet ports on individual Blu-ray Disc Players is optional.

HD-DVD - General Specifications

Storage Capacity - Pre-recorded playback material (HD-DVD-ROM): Single-layer (15GB) - Dual-layer (30GB) - Triple Layer (51GB - developed, but never brought to market).

Storage Capacity - Home Recording (HD-DVD-R/HD-DVD-Rewritable): Single-layer (20GB) - Dual-Sided Disc (40GB) - Dual Layer (35GB - proposed).

Data Transfer Rate: 36 MBPS (Megabits per Second) - This exceeds the 19.3 Mbps transfer rate approved for HDTV broadcasts.

Disc Properties: Format similar to existing DVD disc structure, requiring minimal upgrading and retooling of existing DVD disc manufacturing and replication plants.

Video Specifications: Compatible with MPEG2, MPEG4, and VC1 Encoding.

Audio Specifications: All HD-DVD players are required to incorporate the following - Dolby Digital Plus, Dolby TrueHD, DTS-HD, and Uncompressed PCM, as well as standard Dolby Digital and DTS.

Network Capability: All HD-DVD players are required to be network enabled and be equipped with a built-in Ethernet port for downloading firmware updates and other interactive features.

Proceed To Page 2: Blu-ray Disc Format and Player Profiles

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