DVD — BrandWiki

DVD

title	DVD
type	Optical disc
use	Home video, Computer data storage
read	650 nm laser diode, 10.5 Mbit/s (1×)
write	650 nm laser diode, 10.5 Mbit/s (1×)
weight	16 g
released	JP: November 1, 1996‡R1R‡ Asia/CIS: January 1997 US: March 24, 1997‡R2R‡ UK: June 1997 EU: March 1998‡R3R‡ AUS/NZ: February 1999
owner	Sony · Panasonic · Philips · Toshiba
extended from	LaserDisc Compact disc
extended to	DVD+RW · DVD-RAM · HD DVD · Blu-ray

DVD (digital video disc or digital versatile disc)[4][5] is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kind of digital data and has been widely used to store video programs (watched using DVD players), software and other computer files. DVDs offer significantly higher storage capacity than compact discs (CD) while having the same dimensions. A standard single-layer DVD can store up to 4.7 GB of data, a dual-layer DVD up to 8.5 GB. Dual-layer, double-sided DVDs can store up to a maximum of 17.08 GB.[6]

Prerecorded DVDs are mass-produced using molding machines that physically stamp data onto the DVD. Such discs are a form of DVD-ROM because data can only be read and not written or erased. Blank recordable DVD discs (DVD-R and DVD+R) can be recorded once using a DVD recorder and then function as a DVD-ROM. Rewritable DVDs (DVD-RW, DVD+RW, and DVD-RAM) can be recorded and erased many times.

History

Development and launch

Released in 1987, CD Video used analog video encoding on optical discs matching the established standard 120 mm size of audio CDs. Video CD (VCD) became one of the first formats for distributing digitally encoded films in this format, in 1993.[11] In the same year, two new optical disc storage formats were being developed. One was the Multimedia Compact Disc (MMCD), backed by Philips and Sony (developers of the CD and CD-i), and the other was the Super Density (SD) disc, supported by Toshiba, Time Warner, Matsushita Electric, Hitachi, Mitsubishi Electric, Pioneer, Thomson, and JVC. By the time of the press launches for both formats in January 1995, the MMCD nomenclature had been dropped, and Philips and Sony were referring to their format as Digital Video Disc (DVD).[12][13]

On May 3, 1995, an ad hoc, industry technical group formed from five computer companies (IBM, Apple, Compaq, Hewlett-Packard, and Microsoft) issued a press release stating that they would only accept a single format.[14][15] The group voted to boycott both formats unless the two camps agreed on a single, converged standard. They recruited Lou Gerstner, president of IBM, to pressure the executives of the warring factions. In one significant compromise, the MMCD and SD groups agreed to adopt proposal SD 9, which specified that both layers of the dual-layered disc be read from the same side—instead of proposal SD 10, which would have created a two-sided disc that users would have to turn over. Philips/Sony strongly insisted on the source code, EFMPlus, that Kees Schouhamer Immink had designed for the MMCD, because it makes it possible to apply the existing CD servo technology. Its drawback was a loss from 5 to 4.7 Gbyte of capacity.[16][17]

As a result, the DVD specification provided a storage capacity of 4.7 GB (4.38 GiB) for a single-layered, single-sided disc and 8.5 GB (7.92 GiB) for a dual-layered, single-sided disc.[18] The DVD specification ended up similar to Toshiba and Matsushita's Super Density Disc, except for the dual-layer option. MMCD was single-sided and optionally dual-layer, whereas SD was two half-thickness, single-layer discs which were pressed separately and then glued together to form a double-sided disc.[13]

Philips and Sony decided that it was in their best interests to end the format war, and on September 15, 1995 agreed to unify with companies backing the Super Density Disc to release a single format, with technologies from both.[19] After other compromises between MMCD and SD, the group of computer companies won the day, and a single format was agreed upon. The computer companies also collaborated with the Optical Storage Technology Association (OSTA) on the use of their implementation of the ISO-13346 file system (known as Universal Disk Format) for use on the new DVDs. The format's details were finalized on December 8, 1995.[20]

In November 1995, Samsung announced it would start mass-producing DVDs by September 1996.[21] The format launched on November 1, 1996, in Japan, mostly with music video releases. The first major releases from Warner Home Video arrived on December 20, 1996, with four titles being available.[1] The format's release in the U.S. was delayed multiple times, from August 1996,[22] to October 1996,[23] November 1996,[24] before finally settling on early 1997.[25] Players began to be produced domestically that winter, with March 24, 1997, as the U.S. launch date of the format proper in seven test markets.[2]

DTS announced in late 1997 that they would be coming onto the format. The sound system company revealed details in a November 1997 online interview, and clarified it would release discs in early 1998.[31] However, this date would be pushed back several times before finally releasing their first titles at the 1999 Consumer Electronics Show.[32]

In 2001, blank DVD recordable discs cost the equivalent of $27.34 US dollars in 2022.[33][34]

Adoption

Movie and home entertainment distributors adopted the DVD format to replace the ubiquitous VHS tape as the primary consumer video distribution format.[35]

Immediately following the formal adoption of a unified standard for DVD, two of the four leading video game console companies (Sega and The 3DO Company) said they already had plans to design a gaming console with DVDs as the source medium.[36] Sony stated at the time that they had no plans to use DVD in their gaming systems, despite being one of the developers of the DVD format and eventually the first company to actually release a DVD-based console.[36] Game consoles such as the PlayStation 2, Xbox, and Xbox 360 use DVDs as their source medium for games and other software.

Specifications

The DVD specifications created and updated by the DVD Forum are published as so-called DVD Books (e.g. DVD-ROM Book, DVD-Audio Book, DVD-Video Book, DVD-R Book, DVD-RW Book, DVD-RAM Book, DVD-AR (Audio Recording) Book, DVD-VR (Video Recording) Book, etc.).[42][43][44] DVD discs are made up of two discs; normally one is blank, and the other contains data. Each disc is 0.6 mm thick, and they are glued together to form a DVD disc. The gluing process must be done carefully to make the disc as flat as possible to avoid both birefringence and "disc tilt", which is when the disc is not perfectly flat, preventing it from being read.[45][46]

Some specifications for mechanical, physical and optical characteristics of DVD optical discs can be downloaded as freely available standards from the ISO website.[47] There are also equivalent European Computer Manufacturers Association (Ecma) standards for some of these specifications, such as Ecma-267 for DVD-ROMs.[48] Also, the DVD+RW Alliance publishes competing recordable DVD specifications such as DVD+R, DVD+R DL, DVD+RW or DVD+RW DL. These DVD formats are also ISO standards.[49][50][51][52]

Some DVD specifications (e.g. for DVD-Video) are not publicly available and can be obtained only from the DVD Format/Logo Licensing Corporation (DVD FLLC) for a fee of US$5000.[53][54] Every subscriber must sign a non-disclosure agreement as certain information on the DVD Books is proprietary and confidential.[53]

In January 2025, the DVD FLLC announced its own dissolution on January 31, 2025 (together with the DVD Forum itself, according to its charter[55]) and the deposit of the DVD specifications at the National Diet Library of Japan in early 2025.[56]

As of August 2025, the specification documents are only available at the National Diet Library in Tokyo.[57]

Double-sided discs

Borrowing from the LaserDisc format, the DVD standard includes DVD-10 discs (Type B in ISO) with two recorded data layers such that only one layer is accessible from either side of the disc. This doubles the total nominal capacity of a DVD-10 disc to 9.4 GB (8.75 GiB), but each side is locked to 4.7 GB. Like DVD-5 discs, DVD-10 discs are defined as single-layer (SL) discs.[47]

Dual-layer discs

DVD hardware accesses the additional layer (layer 1) by refocusing the laser through an otherwise normally-placed, semitransparent first layer (layer 0). This laser refocus—and the subsequent time needed to reacquire laser tracking—can cause a noticeable pause in A/V playback on earlier DVD players, the length of which varies between hardware.[58] A printed message explaining that the layer-transition pause was not a malfunction became standard on DVD keep cases. During mastering, a studio could make the transition less obvious by timing it to occur just before a camera angle change or other abrupt shift, an early example being the DVD release of Toy Story.[59]

DVD drives and players

DVD drives are devices that can read DVD discs on a computer. DVD players are a particular type of devices that do not require a computer to work, and can read DVD-Video and DVD-Audio discs.

Transfer rates

Read and write speeds for the first DVD drives and players were 1,385 kB/s (1,353 KiB/s); this speed is usually called "1×". More recent models, at 18× or 20×, have 18 or 20 times that speed. For CD drives, 1× means 153.6 kB/s (150 KiB/s), about one-ninth as swift.[68][70]

DVDs can spin at much higher speeds than CDs – DVDs can spin at up to 32000 RPM vs 23000 for CDs.[73] In practice, they are not spun by optical drives anywhere close to these speeds to provide a safety margin. DVD drives limit reading speed to 16× (constant angular velocity), which means 9280 rotations per minute. Early-generation drives released before the mid-2000s have lower limits.[74]

DVD recordable and rewritable discs can be read and written using either constant angular velocity (CAV), constant linear velocity (CLV), Partial constant angular velocity (P-CAV) or Zoned Constant Linear Velocity (Z-CLV or ZCLV).[75]

Due to the slightly lower data density of dual layer DVDs (4.25 GB instead of 4.7 GB per layer), the required rotation speed is around 10% faster for the same data rate, which means that the same angular speed rating equals a 10% higher physical angular rotation speed. For that reason, the increase of reading speeds of dual layer media has stagnated at 12× (constant angular velocity) for half-height optical drives released since around 2005, and slim type optical drives are only able to record dual layer media at 6× (constant angular velocity), while reading speeds of 8× are still supported by such.[80][81][82]

Disc quality measurements

The quality and data integrity of optical media is measureable, which means that future data losses caused by deteriorating media can be predicted well in advance by measuring the rate of correctable data errors.[83]

The types of errors that can occur on a DVD are a PIE (Parity Inner Error), 8PIE (Parity Inner Sum Eight Error), PIF (Parity Inner Failure), POE (Parity Outer Error), and POF (Parity Outer Failure), the last of which indicates data loss. Too many small errors within a small space create a POF condition. The difference between POE and POF is that a POE is generated on a first failed read attempt whereas a POF indicates an uncorrectable error after repeated attempts to read the data.[84]

Support of measuring the disc quality varies among optical drive vendors and models.[85][86] Unreadable data can be found using any drive using general-purpose tools like badblocks.

Successors and decline

In 2006, two new formats called HD DVD and Blu-ray Disc were released as the successor to DVD. HD DVD competed unsuccessfully with Blu-ray Disc in the format war of 2006–2008. A dual layer HD DVD can store up to 30 GB and a dual layer Blu-ray disc can hold up to 50 GB.[89][90]

However, unlike previous format changes, e.g., vinyl to Compact Disc or VHS videotape to DVD, initially there was no immediate indication that production of the standard DVD would gradually wind down, as at the beginning of the 2010s they still dominated, with around 75% of video sales and approximately one billion DVD player sales worldwide as of April 2011. In fact, experts claimed that the DVD would remain the dominant medium for at least another five years as Blu-ray technology was still in its introductory phase, write and read speeds being poor and necessary hardware being expensive and not readily available.[91][92]

Consumers initially were also slow to adopt Blu-ray due to the cost.[93] By 2009, 85% of stores were selling Blu-ray Discs. A high-definition television and appropriate connection cables are also required to take advantage of Blu-ray disc. Some analysts suggested that the biggest obstacle to replacing DVD was due to its installed base; a large majority of consumers were satisfied with DVDs.[94] DVDs started to face competition from video on demand services around 2015 or 2016.[95][96][97][98] With increasing numbers of homes having high speed Internet connections, many people had the option to either rent or buy video from an online service, and view it by streaming it directly from that service's servers, meaning they no longer need any form of permanent storage media for video at all. By 2017, digital streaming services had overtaken the sales of DVDs and Blu-rays for the first time.[99]

Until the end of the 2010s, manufacturers continued to release standard DVD titles, and the format remained the preferred one for the release of older television programs and films. Shows that were shot and edited entirely on film, such as Star Trek: The Original Series, could not be released in high definition without being re-scanned from the original film recordings.[100] Shows that were made between the early 1980s and the early 2000s were generally shot on film, then transferred to video tape, and then edited natively in either NTSC or PAL; this makes high-definition transfers impossible, as these SD standards were baked into the final cuts of the episodes. Star Trek: The Next Generation was the only such show that had a Blu-ray release, as prints were re-scanned and edited from the ground up.[101]

By the beginning of the 2020s, sales of DVD had dropped 86% with respect to the peak of DVD sales around 2005, while on-demand sales and, overall, subscription streaming of TV shows and movies grew by over 1,200%. At its peak, DVD sales represented almost two thirds of video market in the US; approximately 15 years later, around 2020, they fell to only 10% of the market.[102]

By 2022, there was an increased demand of high definition media, where Ultra HD Blu-ray and regular Blu-ray formats made up for almost half of the US market while sales of physical media continued to shrink in favor of streaming services.[103]

The decline continued further into the 2020s with the closure of RedBox in 2024, Best Buy and Target stopped selling DVDs in 2023, and the cease of by mail service by Netflix in 2025.[104]

DVD

Etymology

History

Development and launch

Adoption

Specifications

Double-sided discs

Dual-layer discs

DVD recordable and rewritable

Dual-layer recording

Capacity

DVD drives and players

Transfer rates

Disc quality measurements

DVD-Video

Security

Successors and decline

Longevity

See also

Further reading

External links

References

Combinations of the above