Toshiba

The HD DVD format also applies to current red laser DVDs; this type of disc is called “3× DVD”, as it is capable of three times the bandwidth of regular DVD-Video.

3× DVDs are physically identical to normal DVDs. Although 3× DVDs provide the same high definition content, their playback time is less. For example, an 8.5 GB DVD can hold about 85 minutes of 1080p video encoded with VC-1 or AVC at an average bitrate of 13 Mbit/s, suitable for short subjects (training films, home movies, very short feature films), but unsuitable for most feature film-length content.

It is technically possible for consumers to create HD DVD compatible discs using low cost DVD-R or DVD+R media. At least one such guide exists. The 3× DVD is comparable to Blu-ray BD5 and BD9 formats.

Warner Bros. officially announced Total Hi Def (THD or Total HD) at CES 2007. THD hybrid discs were to support both HD DVD and Blu-ray, with HD DVD on one side (up to two layers) and Blu-ray on the other side (up to two layers). However, in November 2007 Warner Bros. cancelled THD development.

There are two types of hybrid formats which contain standard DVD-Video format video for playback in regular DVD players, and HD DVD video for playback in high definition on HD DVD players. The Combo disc is a dual sided disc with one side DVD and the other HD DVD, each of which can have up to two layers. The Twin disc is a single sided disc that can have up to three layers, with up to two layers dedicated to either DVD or HD DVD. These hybrid discs make retail marketing and shelf space management easier. Another advantage is hardware cross-compatibility. The average consumer doesn’t have to worry about whether or not they can play a hybrid DVD: any standard home DVD player can access the DVD-encoded content and any HD DVD player can access both the DVD- and HD DVD-encoded content.

HD DVD-R is the writable disc variant of HD DVD, available with a single-layer capacity of 15 GB or a dual-layer capacity of 30 GB. Write speeds depend on drive speed, with a data rate of 36.55 Mbit/s (4.36 MB/s) and a recording time of 56 minutes for 1× media, and 73 Mbit/s (8.71 MB/s) and a recording time of 28 minutes for 2×.

The Toshiba SD-L902A for notebooks was one of the first available HD DVD writers, although it was not meant for retail. Burning HD DVD (including Dual Layer) with a 1× write speed, it could also burn DVDs and CDs. In a test of the SD-L902A by C’t computer magazine with Verbatim discs, the written HD DVD-Rs suffered from high noise levels as a result, the written discs could not be recognized by the external HD DVD drive of the Xbox 360, though they could be read back by the SD-L902A.
HD DVD-RW is the rewritable disc variant of HD DVD with equal storage capacity to an HD DVD-R. The primary advantage of HD DVD-RW over HD DVD-R is the ability to erase and rewrite to an HD DVD-RW disc, up to about 1,000 times before needing replacement, making them comparable with the CD-RW and DVD-RW standards. This is also of benefit if there are writing errors when recording data, as the disc is not ruined and can still store data by erasing the faulty data.

HD DVD-RAM was the proposed successor to DVD-RAM for random access on optical media using phase-change principals. It would hold 20 gigabytes per layer instead of 15 gigabytes for HD DVD-R, due to differences in recording methods used, yielding a higher density disc. The future of this format is uncertain, given Toshiba’s announcement of withdrawal of support for the HD DVD format as a whole.

HD DVD competed primarily with Blu-ray Disc. Both formats were designed as successors to DVD, capable of higher quality video and audio playback, and of greater capacity when used to store video, audio, and computer data. Blu-ray and HD DVD share most of the same methods of encoding media onto disks with each other, resulting in equivalent levels of audio and visual quality, but differ in other aspects such as interactive capabilities, internet integration, usage control and enforcement, and even in the degree to which their specifications are fixed. The storage size also varies: A dual-layer HD DVD holds a maximum of 30 GB of data, while a dual-layer Blu-ray carries 50 GB.

In 2007, LG and Samsung released standalone consumer players that could read both HD DVD and Blu-ray discs. The machines were sold at premium prices, but failed to sell in large quantities. In May 2008, both companies announced they would stop manufacturing dual-compatibility drives

A few computer manufacturers (most notably HP and Acer) sold computers with combination HD DVD/Blu-ray drives.

Released at the end of November 2006, the Microsoft HD DVD drive for the Xbox 360 game-console gives the Xbox 360 the ability to play HD DVD movies. The drive was announced with an MSRP of US$199 and includes a USB 2.0 cable for connection to the console. The first drives also included Peter Jackson’s King Kong on HD DVD. The final “regular” for the drive was US$129.99 as of February 25, 2008. On February 23, 2008 Microsoft discontinued the Xbox 360 HD DVD player. On February 26, 2008, Microsoft “officially” announced that the Xbox 360 HD DVD add on drive would reflect a heavily discounted price down to $49.99 In Europe similar price cuts were observed, as low as 9.99 Euros(around 15 USD) in the Republic of Ireland.

HD DVD drives can also be used with a desktop/laptop personal computer (PC) running Windows XP, Windows Vista, Mac OS X v10.5 “Leopard”, and many varieties of Linux. Third-party player software for Windows and Linux have successfully played HD DVD titles using the add-on drive. First-party (Apple, Inc.) player software is included with Leopard, making it the first operating system (OS) to ship with native HD DVD playing software, albeit limited to HD DVDs authored by DVD Studio Pro.

Backward compatibility is available with all HD DVD players, allowing users to have a single player to play all types of HD DVD, DVD and CD. There is also a hybrid HD DVD format which contains both DVD and HD DVD versions of the same movie on a single disc, providing a smooth transition for the studios in terms of publishing movies, and allowing consumers with only DVD players to still use the discs. DVD replication companies can continue using their current production equipment with only minor alterations when changing over to the format of HD DVD replication. Due to the structure of the single-lens optical head, both red and blue laser diodes can be used in smaller, more compact HD DVD players.

HD DVDs use the HDi Interactive Format to allow interactive content to be authored for discs. HDi is based on web technologies such as HTML, XML, CSS, SMIL, and ECMAScript (JavaScript), so authoring in HDi should be a fairly easy transition for web developers. No existing DVD authoring experience is required. In contrast, Blu-ray Disc content is authored using either a scripting environment for basic content, or a Java-based platform (BD-J) for advanced content. DVD video discs utilize pre-rendered MPEG segments, selectable subtitle pictures, and simple programmatic navigation which is considerably more limited.