| HD DVD, High Density DVD, or High-Definition DVD is | | | | their house. The HD DVD format also can be applied |
| a high-density optical disc format designed for the | | | | to current red laser DVDs in 5, 9, 15 and 18 GB |
| storage of data and high-definition video. | | | | capacities which offers a lower-cost option for |
| History | | | | distributors, this type of disk is often called 3x DVD as |
| The HD DVD disc is designed to be the successor to | | | | it has three times the bandwidth of regular DVD video. |
| the standard DVD format. It can store about three | | | | Like the original DVD format, the data layer of an HD |
| times as much data as its predecessor. (15 GB per | | | | DVD disc is 0.6 mm below the surface. The numerical |
| layer instead of 4.7 GB) The HD DVD standard was | | | | aperture of the optical pick-up head is 0.65, compared |
| jointly developed by a group of consumer electronics | | | | with 0.6 for DVD and 0.85 for Blu-ray aperture. Both of |
| and PC companies, spearheaded by Toshiba. On | | | | the new formats are backward compatible with DVDs |
| November 19, 2003, the DVD Forum voted to support | | | | and both employ the same video compression |
| HD DVD as the HDTV successor of the standard | | | | techniques: MPEG-2, Video Codec 1 (VC-1) and H.264 |
| DVD. At this meeting, they also renamed it HD DVD. | | | | MPEG-4 AVC. |
| The format had previously been called the "Advanced | | | | File systems |
| Optical Disc" (AOD). | | | | Like previous optical disc formats, HD DVD supports |
| At CES 2006, Microsoft announced that there would | | | | several file systems, like ISO 9660 and Universal Disk |
| be an external add-on HD DVD drive for the Xbox | | | | Format (UDF). Currently, all HD DVD titles use UDF |
| 360 game console; this was released in November | | | | version 2.5 as the file system, the same one used for |
| 2006. Also at CES [1]2006, companies backing HD | | | | Blu-ray releases. |
| DVD said that nearly 200 titles would be available for | | | | Audio |
| the format by the end of the year. | | | | HD DVD can be mastered with up to 7.1 channel |
| On March 31, 2006, Toshiba released their first HD | | | | surround sound using linear (uncompressed) PCM, |
| DVD player in Japan at Y110,000 ($934).[2] HD DVD | | | | Dolby Digital, Dolby Digital EX, DTS and DTS ES |
| was released in United States on April 18, 2006,[3] with | | | | formats also used on DVDs. In addition, it also supports |
| players priced at $499 and $799. | | | | Dolby Digital Plus and the lossless formats Dolby |
| The current specification version for HD DVD-ROM | | | | TrueHD and DTS HD. Currently, most DVD movies |
| and HD DVD-Rewritable is version 1.0. The | | | | are made with 5.1 channels of surround sound. There |
| specification for HD DVD-R is currently at 0.9. The first | | | | are relatively few titles that offer 6.1 channels of |
| HD DVD-ROM drives were expected to be unveiled | | | | surround sound. On HD DVD the Dolby formats are |
| by Q4 2006, with mass production to start in Q1 2007. | | | | mandatory, meaning that a Dolby Digital, Dolby Digital |
| The actual product launch of both CE and PC units | | | | Plus or Dolby TrueHD track may be used as the sole |
| occurred in late 2006. As of December 2006, more | | | | soundtrack on a disc, because every player will have |
| than 120,000 HD DVD's had been sold in the United | | | | a decoder that can process any of these bitstreams. |
| States.[citation needed] | | | | For lossless audio in movies in the PCM, Dolby TrueHD |
| As of February 2007, HD DVD is in a format war with | | | | or DTS-HD formats, HD DVD discs support encoding |
| Blu-ray Disc. | | | | in up to 24-bit/192 kHz for two channels, or up to eight |
| Technical specifications | | | | channels of up to 24-bit/96 kHz encoding. For |
| Hardware | | | | reference, even new big-budget Hollywood films are |
| HD DVD has a single-layer capacity of 15 GB and a | | | | mastered in only 24-bit/48 kHz, with 16-bit/48 kHz |
| dual-layer capacity of 30 GB. There is also a | | | | being common for ordinary films. |
| double-sided hybrid format which contains standard | | | | Video |
| DVD-Video format video on one side, playable in | | | | The HD DVD format supports a wide variety of |
| regular DVD players, and HD DVD video on the other | | | | resolutions, from low-resolution CIF and SDTV, all video |
| side for playback in high definition on HD DVD players. | | | | resolutions supported by the DVD-Video standard, and |
| These hybrid discs make retail marketing and shelf | | | | up to HDTV formats such as 720p, 1080i and 1080p.[6] |
| space management easier. This also removes some | | | | All movie titles released so far have had the feature |
| confusion from DVD buyers since they can now buy | | | | encoded in 1080p, with supplements in 480i or 480p. |
| a disc compatible with any DVD/HD DVD player in | | | | Most titles are encoded with VC-1. |