DVD, The Latest Innovation
By Maryann Williams- INTRODUCTION
- DVD STANDARD OVERVIEW
- MAIN SPECIFICATIONS
- DVD DETAILS
- DVD ISSUES
- CONCLUSIONS
- REFERENCES
Just when you thought you were keeping abreast of technology, a new breakthrough in digital storage hit the stores this year. This new technology, DVD, which stands for Digital Versatile Disc or Digital Video Disc, is the next generation of optical disc storage. This technology has taken a few years to get here, but not without problems. The major delay was the battle in reaching an agreement for the standards of the DVD manufacturing specifications. But what exactly does this new technology do for the consumer?
This new DVD technology produces a larger, faster CD that can hold video as well as audio and computer data. The aim of the DVD manufacturers is to incorporate home entertainment, computers, and business information into a single digital format, to eventually replace audio CD, videotape, laserdisc, and CD-ROM (Taylor, 1997).
Several manufacturers introduced the movie players--the introductory DVD product--in the United States in February 1997, with a strong push from the movie industry, particularly Sony and Time Warner. The price varied from $500 to $1,800, and will be supported by an initial 50 movie titles released for viewing in this format. The computer DVD-ROM drives will be the next product released, with a price range from $200 to $500 for a basic drive. This type of drive requires an MPEG-2 decompression computer board or built-in MPEG-2 electronics that can be used as a movie player for TV use. The final specification for the format of DVD-Audio has still not been decided. One issue of debate centers on sizing the discs, with proposals ranging between 8 and 12 cm.
The current single-sided, single-layer, 5-inch DVD storage capacity is 4.7 gigabytes. This equates to 133 minutes of movie play time (assuming three audio streams and a video quality/bit rate of 3.5 megabits per second) (Barker, 1996). There are two 0.6 mm discs (substrates) bonded together to form a disc equal in size to a standard CD. If information is included on the second substrate, the disc capacity is doubled to 9.4 gigabytes, but will probably require that the disc be manually flipped for full access. The price of video discs will vary but should be as cheap as videotapes at a cost of around $25. The cost of DVD-ROMs will be more than CD-ROMs because more information can be stored on them, and the cost to replicate is higher. But as usual, costs should drop as more discs are sold.
The problems began back in 1994 when Sony was trying to standardize its version of the DVD, called MultiMedia or M2. In December of that year, Sony had hoped to win the backing from such companies as Philips Electronics, Matsushita Electric, Thompson Con sumer Electronics. By the end of December, Sony had failed. The only ally of Sony's M2 standard was Philips, its partner from the Netherlands. Sony was the company that lost the Betamax-VHS videocassette standards war and was now called the underdog in the DVD battle (Lemos, 1995). Toshiba and Matsushita, teamed with Hitachi, MCA, Pioneer, Thompson, and Time-Warner to back a different format of the DVD which they called the super disc (SD) standard.
Both standards were based on the universal compact disc (CD) format of 1.2 mm thickness and 12 cm in diameter. The main technological difference between the M2 and the SD standards was that the MS used a single-sided, two-layer approach, while the SD us ed a double-sided disc. Sony had argued that its M2 DVD standard would reduce production costs. Once again they had failed when they miscalculated the cost for production changeover. By March of 1995, Toshiba and Pioneer announced that they would mass produce DVD players using the SD standard in the summer of 1996. Following this announcement, Matsushita acknowledged that they developed a method to use the SD standard as a two-layer disc, which ended the debate over the advantages of M2's two-layer ap proach.
A group of computer companies led by IBM insisted that the DVD sponsors agree on a single standard. After all the arguing, the finalized DVD standard for read-only discs was announced on December 8, 1995. Toshiba, Matsushita, Sony, Phillips, Time-Warner, Pioneer, JVC, Hitachi, and Mitsubishi Electric completed the technical specifications for the DVD movie player and the ROM (read only memory). This collaboration of efforts among these companies avoided the expensive and disconcerting repeat of the VHS vs. BetaMax videotape battle. The specifications for the DVD are as follows (DVD Standards Finalized, 1996):
| Disc Diameter: 120mm (5 inches) |
|---|
| Disc Thickness: 1.2mm (0.6mm thick disc x 2) |
| Memory Capacity: 4.7 gigabytes/single side |
| Track Pitch: 0.74 micrometer |
| Wave Length of Laser Diode: 650 nanometer/635 nanometer |
| Numerical Aperture (NA): 0.6 |
| Error Correction: RS-PC (Reed Solomon Product Code) |
| Signal Modulation: 8 - 16 |
Although there is no single company which owns DVD per se, there is the DVD Licensor Consortium which is comprised of the following ten companies who control the specification: Sony, Philips, Time-Warner, Toshiba, Hitachi, JVC, Matsushita, Mitsubishi, Pi oneer, and Thompson. All of the companies involved in the Consortium are Japanese, except for two European and one U.S. company. They contribute patents and other technology to the design and implementation of DVD, agree to conform to the standard, and receive a share of the licensing revenue that will be collected by an administrative entity. If a company wants to manufacture DVD products, it must license the technology from a pool of companies administered by Philips, but also separately from Thompso n.
The DVD video can provide over two hours of high quality digital video with support for wide-screen movies and regular or wide-screen televisions. It has the capability of providing up to eight tracks of digital audio for multiple languages, and up to 32 subtitle karaoke tracks. It also has a much higher durability over existing video tapes which wear out from playing. The DVDs are heat resistant and not susceptible to magnetic fields. They are also compact, portable and easy to handle and store. The y have the capability of producing near studio quality video and better quality audio than CD.
The one hurdle that is still unresolved is the issue concerning the copyright protection. There has not been a resolve as to how the DVD manufacturers are going to keep the public from making illegal copies of movies. There have been proposals made to t he government for copyright legislation from the Consumer Electronics Manufacturers Association (CEMA) and the Motion Picture Association of America (MPAA). Because of the vague wording of this proposal, it affected every other device or system through w hich a video stream would pass including those that did not even use video display. Since April, 1996, there has been an ad hoc group of 90 representatives from 60 companies called the Copy Protection Technical Work Group, that has been trying to come up with a resolve to appease all parties involved.
Another concern of the movie industry is to control the viewing of new DVD releases in market areas where it is just hitting the silver screen. This concern lies mainly in European countries where theater releases are far behind the United States. DVD players sold in each region will have a code built into the player that will only play discs allowed in that region. This will mean that some discs bought in one region may not be compatible in another country. But as the technology advances, companies will develop ways to negate the regional coding of players.
The three things that make DVDs so exciting to the market are its capacity, interoperability, and backward capatibility with the CD-ROM. They will slowly replace the CD-ROMs just like the CD-ROMs replaced the vinyl LPs. But there could be potential pro blems with the DVD roll-out to market to make it the super-product of 1997. With hardware issues falling into place, the biggest problem for consumers will be finding the disks to use. Titles will not be released until the installed base of hardware rea ches critical masses. But perhaps this situation will easily be averted when it comes to the backward compatibility with the CD-ROMs.
With this new change in technology, industry has to force standard compliance and set reasonable prices so that they are affordable to the average consumer if it wants this technology to succeed. The DVD Consortium must strive to make technical choices that will provide the most functional basis for future applications. The technology that will evolve from this new compact disc format will be unpredictable and grow to surprising depths as the disc storage format someday increases to 60 gigabytes as it gets us ready for the millenium.
Barker, David, "The DVD Digital Domain FAQ"
Dodds, Philip, V. W., "DVD Triggers Bid to Legislate Technical Safeguard Standards "
How to Order the DVD Spec
Industry News, "DVD Standards Finalized"
Lemos, R. A., "The DVD Battle: Deja Vu, Digital-Style", Computing Japan"
Taylor, J. H., "DVD Frequently Asked Questions"
IT Standards Home
March 6, 1997
Draft
william@icarus.lis.pitt.edu