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Here Comes DVD: Digital Versatile Disc
    for Video & Computers (4/1999)

(See New Features in DVD Players)

Just when you might have been getting comfortable with the idea of creating your own CD-ROMs to replace floppy disks, along comes the next great new technology which makes even CD-ROM look puny by comparison. DVD (Digital Versatile Disc) is more than a bigger disc, it is the great industry hope for the next new breakthrough consumer electronics gizmo. You may have noticed DVD video players for sale at the local Best Buy, or movies on DVD discs starting to appear at your local video rental store, or new computers with DVD drives instead of CD-ROMs. What's this all about?

cd_disc3.jpg (3739 bytes)

DVD combines the benefits of cool new digital video and audio technology with the marketing desire to have a whole new generation of consumer products to sell. DVD's are certainly versatile: They promise to replace VCR videotapes, and audio CD's, and also computer CD-ROM's. However, this promise is diluted by infighting among major companies in the consumer electronics industry who are trying to define and own the fundamental standards.

The technical benefit of DVD is huge: Even though DVD discs are the same physical size as regular CD's, new technology permits them to hold seven times more data per disc. That's 4.7 gigabytes (billion characters) on one DVD, compared to a puny 650 megabytes (million characters) on a CD. In addition, the size can be doubled by simply by using both sides of the disc, and then almost doubled again by actually recording data on a second semitransparent layer, to provide up to a total of 17 Gigabytes per disc. Even better, you can still use your old CD's in a new DVD drive.

The second technical breakthrough with video DVD's is that the video is stored digitally. Even though we're familiar with digital audio on CD's, we're still playing analog videotapes on our VCR's. The resolution of analog tapes is less than regular TV, and the quality suffers further as the tape is played over and over again. With DVD's, the video and the audio are digital, with higher resolution and the same original high quality each time you play them. By applying advanced compression techniques, an entire two-hour movie, plus other related material, can be squeezed onto a single DVD disc.

DVD's also can be much more interactive than videotape. You can use a contents menu to jump directly to a specific portion, and skip around without a long wait for a tape to rewind. While you play a video, you can choose between multiple audio tracks with different languages, or different subtitles, especially for music videos. You also can view a concert from different camera angles, or make a movie interactive by seamlessly jumping between alternate versions of the story.

DVD Video and Audio

The growth of the DVD market has been hampered by industry struggles to develop standards. There are four basic flavors of DVD technology under development: DVD-Video for movies, DVD-Audio for music, DVD-ROM for delivering computer applications and data, and DVD-R/DVD-RAM for recordable computer mass storage. Even though versions of these are being sold today, none of them has a fully settled standard. In today's market, technology moves so fast, and the marketing battles are so heated, that standards are still under development even as the products are fighting for market share.

DVD-Video is available now, and it delivers significantly higher quality digital video and audio with multiple tracks and interactive features. You can buy a DVD player for under $300, with a profusion of analog and digital connectors for hooking up to high-end televisions. You see the benefit for the manufacturers with having these new products to sell, especially as VCR prices dip under $99. Movies on DVD discs also are starting to appear in video stores, also typically at higher prices than tapes.

Unfortunately, this nice common standard is confused by an augmented format called Divx (Digital Video Express). Divx is the brainchild of Circuit City and - get this - a law firm! This could be the future of electronic technology: products with technical limitations imposed by retail stores and law firms in order to extract additional value from the material. In the case of Divx, the idea is to sell you a disc at a price like a rental, or about $4.50. You do not need to return it to a rental store, but you must view it within two days before it expires. You can also pay extra to buy the right to keep watching it. However, you rights are controlled by your Divx DVD player, which needs to be connected to a telephone to check your account and grant you permission to watch your disc.

The benefit of Divx to Circuit City is clear: The store gets to sell a higher-priced DVD player with additional Divx features, and also can sell you Divx discs to watch at home (which is not good news for your local video rental store). The law firm also gets a piece of the action. Meanwhile, your viewing pleasure is recorded and authorized by a central computer database. And you can watch a disc you "own" only if the computer grants permission (and your teenager is not hogging the telephone). And what if you want to watch it upstairs on a different machine, or show it at a friend's house, or give it to a friend, or, heaven forbid, sell it at a yard sale? Tough luck.

Meanwhile, the DVD-Audio standard has lagged behind video and computer applications of DVD. This February the DVD Forum industry consortium finalized the standard, which promises higher quality audio, additional features like liner notes, graphics and video, as well as the ability to provide stereo sound and multi-channel mixes for playback in home theater or automobile environments on the same DVD-Audio disc.

As a result of these technical complications in DVD formats, creating your own DVD-Video disc is not a trivial undertaking. The audio and video material need to be produced, compressed, and then combined together, with various copyright protection mechanisms. Additional material needs to be collected, including alternate video and audio tracks and subtitles. The overall program must be organized into chapters and scenes, with interactive menu selections. And finally, all the material must be laid out and burned onto physical discs.

DVD-ROM for Computers

DVD also has great potential for computers: DVD-ROM provides enhanced DVD's which combine applications with large amounts of data. This DVD-ROM technology for delivering large computer applications already has started replacing CD-ROM drives on new desktop and even laptop computers. Some applications are starting to ship on DVD, especially the multimedia encyclopedias and other large databases that require multiple CD's. You can also play DVD-Video movies on your PC, but the video and audio decompression requires significant processing power. To really enjoy full-screen movies on your PC you need a DVD add-in board with decompression hardware, like the PC DVD kit from Creative for around $250.

Recordable "DVD-R" and rewritable "DVD-RAM" products are also starting to become available for PC's, but there are several different products and technical approaches still battling in the market. These early approaches do not provide the full DVD storage capacity, or compatibility with DVD-ROM, or the ability to make your own DVD-Video movie discs. Recently, the key industry players have agreed to get together and settle on a common format. Until then, these products are mostly useful for large local backups.

DVD Information

    DVD Forum,  www.dvdforum.com
    Divx,  www.divx.com