Tagged: DVD

The acronym DVD originally denoted ‘Digital Video Disc’, but in 1995 it was agreed it should stand for ‘Digital Versatile Disc’ to emphasise the flexibility of the format for different applications.

Superbit (2001 – 2007)

Superbit was a variant on standard DVD-Video introduced in 2001 by the Columbia TriStar Home Entertainment division of Sony.

Superbit DVDs used a higher bit rate transfer process to optimise video quality, and always contained both a 5.1 Dolby Digital and DTS soundtrack. The actual increase in bit rate varied according to the space available on the disc, and the bit rate of the standard DVD version (which itself could vary). They were compatible with standard DVD players and so could carry the DVD logo. Due to the extra space required for video and audio data, bonus material is kept to a minimum or not included at all, though there were a handful of ‘Superbit Deluxe’ releases which carried the bonus material on a second disk. The menus were different to those on the standard DVD release, and were kept simple to save space.

Fewer than 60 titles were released in Superbit format, and Superbit releases typically only sold 2% of the amount of the standard DVD version.

By 2007, Sony was promoting Blu-ray and the Superbit line was dropped.

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DVD-ROM (1997 – )

DVD-ROM (Digital Versatile Disc – Read-Only Memory) is a read-only high-capacity optical disc format. DVD-Video is a form of DVD-ROM, but DVD-ROM usually refers to DVD discs for data storage. Microsoft were the first major corporation to release software on DVD-ROM in 1997.

Capacities range from 4.7GB (for a single-sided, single-layer disc) to 17GB (for a double-sided, dual-layer disc).

DVD-ROM drives are backwards compatible with CD-ROM discs, and can read rewritable DVD media such as DVD-R/DVD+R and DVD-RW/DVD+RW.

Since around 2007, DVD drives (along with optical disc drives generally) have been disappearing from laptops and of course were never available in tablets. Despite this, a lot of computer software is still available on DVD-ROM.

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MiniDVD-R (1997 – )

The MiniDVD-R is a smaller (8cm) version of the DVD-R. MiniDVD-R discs can be used in the same way as 12cm DVD-R discs to hold computer data, but their most common use was in DVD-based camcorders from around 2003 to the early 2010s.

A standard MiniDVD-R could hold 30 minutes of video, with double-layer discs offering 60 minutes (with a compatible camcorder).

The use of MiniDVD-R discs in camcorders made it easier to watch the resulting video on standard tray-loading DVD players (providing the disc was ‘finalised’ in the camcorder first).

Many DVD camcorders could also use other types of DVD discs, such as MiniDVD+R, MiniDVD-RW, MiniDVD+RW and MiniDVD-RAM.

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DVD-R (1997 – )

DVD-R is a recordable optical disc format based on DVD and developed by Pioneer in 1997. It is supported by most DVD players and is approved by the DVD Forum. It is similar to, but incompatible with, the newer DVD+R standard

A double-sided DVD-R typically has a storage capacity of 4.7 GB but a dual-layer double-sided version with a capacity of 8.5 GB, DVD-R DL, was released in 2005. DVD-R is generally used for non-volatile data storage or video applications. A smaller 8cm version of DVD-R (miniDVD-R) is also available for use in camcorders.

Double-sided DVD-R discs are composed of two 0.6 mm acrylic discs bonded to each other, one containing the laser guiding groove and coated with the recording dye and a silver alloy or gold reflector. On single-sided discs, the unused side is simply a blank to make up the thickness to 1.2mm.

Many DVD drives are hybrid drives (normally labeled ‘DVD±RW’) and can read and write to both DVD-R and DVD+R. However, because the DVD-R format has been in use since 1997, it has had a five-year lead on DVD+R which wasn’t introduced until 2002. As such, older DVD players are more likely to favour the DVD-R standard exclusively.

Unlike DVD+R, DVD-R discs do not need to be formatted before being recorded by a compatible DVD video recorder.

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Nintendo Wii Optical Disc (2006 – 2013)

The Ninteno Wii Optical Disc was a proprietary DVD-based format used in the Nintendo Wii games console, introduced in 2006.

The format was created by Panasonic for Nintendo, and is a full sized version of the Nintendo GameCube disc, with the potential capacity of a double-layer DVD-ROM (most early discs were single-layer). The disc reader of the Wii does not play DVD-Video, DVD-Audio or Compact Discs.

The Wii Optical Disc uses a burst cutting area mark on the disc to store encrypted data for copy-protection.

The Wii was a seventh-generation game console, that competed with consoles such as the Microsoft Xbox 360, and Sony PlayStation 3. It introduced the Wii Remote controller, which can be used as a handheld pointing device and which detects movement in three dimensions. Early models were compatible with GameCube discs and with GameCube Memory Cards. Secure Digital cards can be used for uploading photos and backing up saved game data and downloaded Virtual Console and WiiWare games.

The Wii was replaced by the Wii U, and was discontinued in 2013.

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DVD-Video (1998 – )

DVD-Video is a digital optical disc storage format for video playback, developed by Philips, Sony, Toshiba and Panasonic. It was initially available in Japan in 1995, and reached Europe in 1998. The first movie to be released on the new DVD-Video format was Twister, which also happened to be the last film released on HD-DVD.

In 1993, two new optical disc video formats were being developed, Multimedia Compact Disc (MMCD), backed by Philips and Sony, and the Super Density (SD) disc, supported by a number of other manufacturers. Eventually, a joint standard was agreed.

Movie distributors adopted the DVD-Video format to replace the ubiquitous VHS as it produced superior picture and sound quality, could provide interactivity, and the storage capacity allowed for extras or bonus features such as audio commentaries, deleted scenes and trailers. Players were also cheaper to manufacture than complex video tape machines.

Each DVD-Video disc contains one or more region codes, denoting the area(s) of the world in which distribution and playback are intended. The commercial DVD player specification dictates that a player must only play discs that contain its region code but in practice, many DVD players allow playback of any disc, or can be modified to do so.

Currently, DVD-Video is the dominant form of home video distribution worldwide, although in Japan it was surpassed by Blu-ray Disc in 2006. It is now, however, facing competition from video on demand services.

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DIVX (Digital Video Express) (1998 – 1999)

DIVX (Digital Video Express) was short-lived DVD-based video format created by Circuit City as an alternative to video rental in the US. DIVX players became available in mid-1998.

Customer would buy a DIVX disc at lower price than a standard DVD, but they would only be able to view it for 48 hours (longer viewing required a continuation fee). The DIVX players had to call an account server over a phone line to enable playback, and the disc would not play in standard DVD players.

Consumers could simply discard the disc once they had watched it, although several DIVX retailers maintained DIVX recycling bins on their premises.

By March 1999, around 420 titles were available in the DIVX format, however it was discontinued in June 1999 and owners of players provided with a partial refund. Existing discs were viewable until mid-2001, when access to the account server ended.

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DVD+RW (2001 – )

DVD+RW is a rewritable optical disc format based on the DVD, and used in video recorders and computers. It was created by the DVD+RW Alliance, but although the specification was developed in 1997, it wasn’t introduced until 2001 in a revised form that allowed for increased capacity (4.7 GB for single-layer discs).

The recording layer in both DVD+RW and DVD-RW discs is a phase change metal alloy whose state can be switched depending on the power of the writing laser, so data can be written, read, erased and re-written.

The DVD+RW format is different to DVD-RW format, but many drives are hybrid drives (normally labeled ‘DVD±RW’) and can read and write to both formats.

DVD+RW discs are more accurate at higher speeds than DVD-RW, and DVD+RW has a more robust error management system, allowing for more accurate burning to media.

A dual layer DVD+RW specification was approved in March 2006 with a capacity of 8.5 GB, but support for rewritable dual-layer discs did not materialize due to the cost and expected competition from newer formats such as Blu-ray.

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DVD-Audio (2000 – )

DVD-Audio (DVD-A) is an optical disc format for high resolution audio on DVD, and was first introduced in 2000 by the DVD Forum.

DVD-Audio competed with Super Audio CD (SACD), and like SACD could provide longer playing time, far higher audio quality and more channels (such as for surround sound).

Like other DVD discs, DVD-Audio discs can have multiple layers, and can contain both DVD-Video and DVD-Audio content.

Only some major labels have released albums on DVD-Audio, and the number of releases is very small compared to Compact Disc.

DVD-RW (1999 – )

DVD-RW is a rewritable optical disc format with equal storage capacity to a DVD-R, typically 4.7 GB. It was developed by Pioneer in 1999. Standard DVD-RW discs are 120mm, but Mini DVD-RW discs are available with a diameter of 80mm and a capacity of 1.46 GB.

It is claimed that DVD-RW discs may be written to about 1,000 times before needing replacement, and are often used for computer backups and DVD video recorders.

DVD-RW competes with DVD+RW, and many recorders can use both formats.

The recording layer in DVD-RW and DVD+RW is not an organic dye, but a special phase change metal alloy, often GeSbTe. The alloy can be switched back and forth between a crystalline phase and an amorphous phase, changing the reflectivity.

A specification for dual-layer DVD-RW discs with a capacity of 8.5 GB was approved by the DVD Forum, but were not released due to cost and competition from higher-capacity formats like Blu-ray and HD DVD-R.

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