[3.13] What about the HD-DVD and blue laser formats?

HD-DVD (HD stands for both high-density and high-definition) was under development before DVD came out. It finally emerged in 2003 (see 2.12 for general info). Some high-definition versions of HD-DVD use the original DVD physical format but depend on new video encoding technology such as H.264 to fit high-definition video in the space that used to hold only standard-definition video. High-density formats use blue or violet lasers to read smaller pits, increasing data capacity to around 15 to 30 GB per layer. High-density formats use high-definition MPEG-2 video (for compatibility with ATSC and DVB HD broadcasts, see 2.9 ) and may also use advanced encoding formats, probably supporting 1080p24 video.

As of early 2004 there are five proposals for HD-DVD, with the possibility of others. Here's a summary (more detail in the following sections):

Format Backers Data depth Laser Video Capacity (single layer/dual layer) Data rate
HD-DVD DVD Forum 0.6 mm Blue (405 nm) HD MPEG-2, H.264, VC9* 15G / 30G (ROM), 20G / 40G (recordable) 36 Mbps
Blu-ray Blu-Ray Disc Founders 0.1 mm Blue (405 nm) HD MPEG-2 27G / 50G 36 Mbps
EVD eWorld (Govt. of China) 0.6 mm Red (650 nm) HD MPEG-2 (later AVC) na / 8.5G (ROM) 22 Mbps
FVD 1 ITRI (Taiwan) 0.6 mm Blue (405 nm) AVC 17G / na 25.05 Mbps
FVD 2 ITRI (Taiwan) 0.1 mm Blue (405 nm) AVC 17G / na 31.59 Mbps

* VC9 is the SMPTE standard based on Microsoft's Windows Media Series 9.

HD discs will not play on existing players. Even red-laser discs, which the player may be able to physically read, require new circuitry to decode and display the high-def video. Red-laser discs can play on DVD PCs with the right software (for example, HD versions of DVDs using Microsoft HD-WMV were available in 2003). Blue-laser discs require new optical assemblies and controllers. HD players will undoubtedly read existing DVDs, so your collection will not become obsolete when you buy a new player.

None of the HD formats will be used for movies until 2005 or 2006.

HD-DVD-9, aka HD-9
For a while there was a proposal being called HD-DVD-9, which put high-definition video on existing dual-layer DVD-9 discs. It has been combined with HD-DVD (AOD) in the sense that the application format is being designed to work on both current red-laser DVDs as well as future blu-laser DVDs. It's essentially a compatible-but-cheaper-to-replicate companion to blue-laser HD-DVD.

A 2-hour movie can fit on a DVD-9 at data rates of 6 to 7 Mbps. Given advances in video compression technology, it should be possible to get high-definition quality of at least 720p24 at these data rates (720 lines of progressive video at 24 frames/second). Shorter movies could be encoded in 1080p24 format. H.264 (MPEG-4 part 10) and VC9 (Windows Media 9) are the likely encoding standards.

HD-DVD (AOD)
The DVD Forum's next-generation DVD, once called Advanced Optical Disc (AOD), currently being called HD-DVD, but soon to have a new name. AOD is a modification of the existing DVD physical format to enable about 15 GB per layer using a blue-ultraviolet readout laser. The same 0.6-mm data depth is used. AOD is designed to improve data capacity while theoretically being able to use existing replication equipment. It is primarily supported by Toshiba and NEC.

Blu-ray Disc (BD)
Blu-ray is a new high-density physical format that will hold 23 to 27 GB per layer using a blue-ultraviolet laser and a 0.1-mm data depth. Because of the 0.1-mm cover layer it will require significant changes to production equipment. Blu-ray is initially intended for home recording, professional recording, and data recording. Mass-market distribution of pre-recorded movies will come later, after the read-only format, called BD-ROM, is developed and the details of video, audio, interactivity, and copy protection are hammered out. Blue-ray backers are LG, Panasonic, Philips, Pioneer, Hitachi, Mitsubishi, Samsung, Sharp, Sony, and Thomson. Sony released the first BD recorder in Japan in April 2003.

Technical details: up to 27 GB per layer using 0.1-mm recording depth (to reduce aberration from disc tilt), 405-nm blue-violet semiconductor with 0.85 NA (numerical aperture) lens design to provide 0.32 ¦Ìm track pitch (half that of DVD) and as small as 0.138 ¦Ìm pit length. Variations include 23.3 GB capacity with 0.160-¦Ìm minimum pit length (used by Sony's Professional Disc system) and 25 GB capacity with 0.149-¦Ìm minimum pit length. The physical discs uses phase-change groove recording on a 12-cm diameter, 1.2-mm thick disc, similar to DVD-RW and DVD+RW. 36 Mbps data transfer rate. Recording capacity on a single layer is about 2 hours of HD video (at 28 Mbps) or about 10 hours of standard-definition video (at 4.5 Mbps) . Cartridge size is 129 x 131 x 7 mm. Plans are to produce dual-layer recordable discs, holding about 50 GB per side, but such discs will take a few additional years to appear.

EVD
A government-backed consortium of companies in China, called eWorld, has developed a domestic version of DVD called EVD (Enhanced Versatile Disc). EVD uses red laser discs but with tighter tolerances than DVD to hold more data. Video is encoded in HD MPEG-2, although a future version will use the China-developed AVC compression format. EVD players first appeared in China at the beginning of 2004.

FVD 1 and FVD 2
The Advanced Optical Storage Research Alliance (AOSRA), formed by Taiwan's Industrial Technology Research Institute (ITRI) has its own variations of blue-laser formats. FVD 1 uses a 0.6-mm data depth similar to AOD, and FVD 2 uses a 0.1-mm data depth similar to Blu-ray.