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No one person can specifically be credited with the invention of DVD media or the player that plays it. This is because several people in teams at different companies worked on it and came up with DVD player products. The time came when CD technology proved to be inadequate for recording and playing on a single media. The intermediate use of CD in the video CD format was cumbersome at best. Even a normal length movie needed at least two discs, some needed more than that. The capacity of CD was the limiting factor.
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The DVD story
The story really starts with the development of the media. Until the format of recording video on it was finalized, developing a player to replay that recording was not feasible. One had to be sure that one format would become the industry standard so that a player could be made for that standard. Whoever produced the recording or the player, the media and the reproduction machine would work interchangeably with products from other companies. Most benefit accrues when just one standard dominates. Like the VHS and Betamax video tape standards, and the Blu-ray versus HD- DVD in the recent past, it all started with two standards. It is good that in all cases one standard survived. Betamax and HD-DVD died leaving the industry with one standard.
Two proposals for DVD formats were floated by different groups of companies in the entertainment business. One was the MMCD (Multi media compact disc) format floated by the likes of Sony and Philips among others. The rival proposal known as the SD (super density) format had promoters in the form of Toshiba, Matsushita and Time-Warner. Rather than fighting it out in the market place with products, one format introduction was going to be beneficial for everybody around. The SD camp had approached IBM for advice on file systems and IBM intervened and ensured that both camps agreed to a common format. The format specifications were finalized by Dec 1995. Thus there is no single inventor of DVD. The technology is owned by a group of ten companies known as the DVD forum that include Hitachi, JVC, Matsushita, Mitsubishi, Philips, Pioneer, Sony, Thomson, Time Warmer and Toshiba.
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The DVD player
DVD players that could read this DVD format were then developed by many of these companies. Thus there is no inventor for the DVD player either. The name digital versatile disc, rather than digital video disc is the preferred name of the technology. The format specification accommodates recording of audio and data as well as video on the discs. The recording is in the form of small pits on the disc surface and the presence or absence of these pits is read by small wavelength lasers when reproducing the audio/video or data from it. A single layer disk provides a capacity of 4.7 GB.
Toshiba introduced the first player in Nov 1996 in Japan followed by US, Mar 1997 and Europe in Nov 1998. Then, of course, they were everywhere. The media kept evolving, dual layer and dual sided disks started becoming available. With a dual sided, dual layer disk one could have a capacity of 17.08 GB. Recordable and then rewriteable media came along and reading and writing speeds increased. DVD players use a red laser that has an wavelength at 650 nm and can sense as small a pit as 0.74 micro meter compared to 1.6 micro meter of a CD. This contributes to capacity increase straightaway. Blu-rays use blue laser at 405 nm wavelength. You could have 50 GB capacity on one dual layer disc. With the high definition video being demanded more and more you need larger capacities to accommodate a high definition movie on one disc.
The DVD player has to have some additional features such as digital rights management or DRM to prevent rampant digital copying of movie contents put out by the studios. These include CSS or the content scrambling system as well as region code. Players must have capabilities to decode the CSS. Similarly a region code arrangement provides additional protection and plays DVDs sold for that territory only.