[The DVD Lexicon]

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16 x 9
The aspect ratio of widescreen televisions roughly equates to 1.85:1, or 16x9 units. DVDs with "16x9 enhancement" use an anamorphic process to increase resolution on widescreen TVs, and many DVD players can take advantage of the enhancement for standard 4:3 televisions. See also Anamorphic.

See Mono

See Stereo

See Aspect Ratio

See Dolby Digital

See THX Surround EX

See Dolby Digital

Academy Ratio
The first conventional aspect ratio of films, being 4:3. See also Aspect Ratio.

Amaray keep-case
See keep-case.

Refers to a conventional widescreen process of film projection. With anamorphic lenses, the image is "squeezed" into standard 4:3 frame and then projected by another anamorphic lens in the widescreen format. If you have a standard television, you can see the anamorphic image by setting your DVD player's video output to 16x9 and playing a 16x9 enhanced disc. See also Aspect Ratio.

Breakup of the picture on DVD which results in the image looking "blocky" or "pixellated." A result of poor mastering. See also Transfer.

Aspect Ratio
Put simply, the aspect ratio of the film projection (and the shape of the film on your television) is expressed in width divided by height. The first widely adopted aspect ratio of film was 4:3, meaning that the width of the picture was one part wider than its height. This standard became known as the "Academy ratio." Your television, when the entire image area is used, is 4:3, just like early films, because when the television standard was invented in the late 1940s, the existing cinematic standard was utilized, and such is why many older films (Casablanca, The Philadelphia Story) fit your television screen perfectly.

After television entered American households in the 1950s, Hollywood studios encountered an inevitable drop-off in theater attendance. One response was to film movies in "widescreen," and several formats from different studios were promoted.

There are two major standard widescreen ratios in effect today: 2.35:1 and 1.85:1 (although you may see variants from as wide as 1.66 to 2.60). When you view DVDs in widescreen (known as "letterboxing" in home-video parlance because the top and bottom of your television screen will be rendered in black to compensate for the wider aspect ratio), these are the two aspect ratios you will most likely encounter.

Acronym for "Audio-Video," a general term for home theater equipment, e.g. "I have spent so much money on A/V equipment that my wife moved out."

My Wife Moved Out
Also known as "My Girlfriend Left Me," "She's Nuts," and "I Just Got Hit on the Head with Something from Pottery Barn." A common ailment of A/V consumers.


Acronym for "consumer electronics."

Content Scrambling System
An encryption technology designed for the DVD format to prevent easy copying of DVD movies onto blank DVD media with DVD-ROM drives. Cracked by a group of Norwegian hackers in November of 1999 with a small, easily obtainable program dubbed "DeCSS."

A tricky concept, but essentially the point where the bass signal is dropped from your front woofers and transferred by your amplifier to your subwoofer. The crossover should be adjusted on your subwoofer to match the lowest Hz of your fronts, which is normally around 80 Hz. However, if your fronts go lower than this, by all means drop your crossover, because a higher Hz on your subwoofer will create greater directionality, and the LFE signal is not supposed to be directional at all. See also LFE.

Acronym for "Cathode Ray Tube." See Front-view television

Shorthand for Dolby Digital.

Direct Stream Digital Audio
See DVD Audio

Acronym for Digital Video Express, a rental-scheme variant of DVD owned by retailer Circuit City and a Los Angeles law firm. Subject of strident criticism on the Internet and elsewhere, Divx officially stopped registering new customers on June 16, 1999, and ceased all operations in June of 2001. See The DVD Journal's What Was Divx? page for further information.

Dolby, Dolby Laboratories
Vanguard audio corporation with an extensive history in the innovation and improvement of audio, much of which has nothing to do with DVD, including the famous Dolby Noise Reduction technology that reduces tape hiss on audio cassettes. But Dolby also has been the leader in film sound for several decades, and their Dolby Digital audio code is the standard for both DVD and HDTV.

  • Dolby Stereo (Dolby Surround): The original Dolby theatrical audio standard relied on two front channels, the center channel, and two-limited bandwidth surround channels, sourced from a matrixed stereo soundtrack. Called Dolby Stereo in the theaters, is was dubbed "Dolby Surround" when it first appeared on early home-theater amplifiers in the 1980s (which could only decode left, right, and surround data).
  • Dolby Stereo (Dolby Pro Logic): When the center channel became viable in home theaters, Dolby "Pro Logic" decoders were marketed to deliver the entire sonic experience. However, Dolby Stereo was never was never called Pro Logic in theaters.

  • Dolby Digital: Theatrical sound system first introduced in 1991 (on Batman Returns) by Dolby Laboratories, which improved upon the previous "Dolby Stereo" (i.e., Pro Logic) by creating five discrete channels of digital sound via two front speakers, two rear speakers, and a center-channel speaker, as well as a limited-bandwidth LFE (low-frequency effects) channel to be transmitted by one or more subwoofers. Because of these five and something-less-than-one channels of discrete audio signals, Dolby Digital is known in shorthand as simply "5.1 audio," the .1 being the LFE channel. The system is also known as "AC-3," which is short for "Audio Code 3," the working name for the format at Dolby HQ. However, Dolby chose to drop this moniker before the format reached the general public, presumably because it was more than a little arcane. Still, home theater nuts love to say AC-3, kind of like beer drinkers like to say "hoppy," because only the initiated really know what the hell anybody means by that anyway.
  • THX Surround EX: A new generation of Dolby theatrical audio, developed in partnership with THX, adds a rear center channel, or a center surround channel, or... well, it's the speaker directly behind you, okay? First appearing with Star Wars: The Phantom Menace on Memorial Day 1999, the format will soon appear on home-theater amps, but only those that are part of the THX "Ultra" line (and therefore have paid the licensing fee to THX in addition to the standard Dolby fee). Whether consumers will buy 'em in droves remains to be seen, but that third rear channel is mighty nice.

Acronym for "Digital Theater Systems," a discrete multi-channel audio system for theatrical films. Arriving shortly after Dolby Digital, DTS, while not the DVD Video standard (that title belongs to Dolby Digital), has entered the home theater marketplace with DTS audio discs, DVD movies, and DTS chips in many DVD players and HT amplifiers. Some people say DTS is better than Dolby Digital; others say it's merely louder, or that it has too much bass in the mix.


Originally an acronym for "Digital Video Disc," although the subsequent introduction of DVD-ROM drives and extensive software programs has caused this to also mean "Digital Versatile Disc." As of now, there is no one actual meaning for the acronym DVD.

The technical definitions of DVD discs are as follows:

  • DVD-5 (SS-SL): The most common type of DVD, single-sided and single-layered, offering about two hours of content. Perfect for most movies. DVD-5s have a silver hue.
  • DVD-9 (SS-DL): Most often a "reverse-spiral dual-layer" (RSDL) DVD, which allows for a little less than four hours of content to be placed on one side of the disc with a brief (sometimes undetectable) layer-switch between two layers of data. DVD-9s without layer-switches are also being produced for films shorter than two hours, offering both widescreen and pan-and-scan editions of a film on a single side and asking the viewer to select the aspect ratio from the DVD menu. DVD-9s can be identified by their gold hue. See also RSDL.
  • DVD-10 (DS-SL): The "flipper" -- a format that has fallen out of favor since DVD-9 was introduced, offering about two hours of content on either side and requiring side-breaks for longer films. However, while true "flippers" are rarely produced anymore, the DVD-10 format is still used by some vendors who place widescreen and pan-and-scan editions of films on either side of the disc. Just like DVD-5s, DVD-10s also have a silver hue, on either side of the disc.
  • DVD-18 (DS-DL): A new generation of DVDs that, like DVD-10s, are flippers, but also use RSDL formatting on both sides to allow up to eight hours of content to be programmed on a single disc. Like DVD-9s, DVD-18s have a gold hue, but on both sides of the disc.

DVD Audio
The DVD Audio standard does not concern movies and other video content, but audio programming (with video clips in DD 5.1 as an optional feature). Most DVD Video players prior to 2000 did not support the DVD Audio standard (based on the six-channel Meridian Lossless Packing technology).

The Super Audio CD, a new format from Sony and Philips (based on Sony's Direct Stream Digital Audio technology), is vying with DVD Audio to be the standard as the next generation of hi-res digital audio, but mainstream consumers apparently don't believe that either DVD-A or SACD represent a substantial improvement over the PCM standard of Compact Disc, and neither will likely replace PCM for some time to come — even though DVD Audio offers a multi-channel surround format. As of this point, portable and convenient (and easily shared) MP3 files seem to represent the future of consumer audio, not DVD discs. See also PCM.

Refers to both the ROM drive on personal computers that reads DVD discs and DVD-ROM content. Some DVD Video discs contain additional DVD-ROM content as an extra feature.

DVD Video
Refers to the industry standard for DVDs that contain video content, such as movies and music concerts.

Forget it. You probably can't afford it.

A DVD movie, normally longer than about two hours, that is split across two sides of the disc, requiring the disc to be ejected and re-inserted at a side break. Widely abandoned by studios after the first few years of DVD Video due to negative consumer feedback.

Front-view television
In a nutshell, any TV that has a tube (technically, a cathode-ray tube) is known as a front-view television. Good if you like to watch TV in ambient light, or just don't have a lot of space.

It won't happen now, but HD-Divx was a proposed high-definition format of movies on Divx discs announced by Divx and Thompson Electronics at the 1999 Consumer Electronics Show. Divx ceased all operations in June of 2001. See also Divx.

The next generation of DVD Video abandons the red-laser technology of the original codec, opting for the higher-definition blue-laser technology, which only emerged from laboratories in recent years. However, the migration towards higher-definition DVD Video has been hampered by competition between two competing standards, "Blu-ray" and "HD DVD." (Those in the Blu-ray camp include Sony, Samsung, Hewlett-Packard, Panasonic, LG Electronics, Sharp, Mitsubishi, Dell, Disney, and Fox. Those supporting HD DVD include Toshiba, NEC, Paramount, Universal, Warner, and New Line.)

Noting that DVD Video launched successfully in 1997 in 1998 precisely because one standard was agreed upon by all consumer-electronics manufacturers and studios that supported DVD at the time, it's not hard to be a little cynical about "high-definition" DVD — not that the technology to produce 30GB discs doesn't exist (it does), but that widespread consumer acceptance probably will require a single codec, lest we wind up in another VHS-Betamax war with winners and losers. Or even worse, DVD-Audio vs. SACD, in which very few people care.

Acronym for "high definition television." The U.S Government tells us that we will all own these new digital television sets in the next few years, but American consumers have to go out and buy them first. HDTV itself is a very complicated matter, with no one standard dominating the format and some cable companies agonizing over the high-bandwidth signals.

Home Theater in a Box
See Sub/Sat

Shorthand for "home theater."

The most common type of DVD case consisting of a durable plastic shell. Amaray manufactured the first keep-cases, but they are currently made by several other vendors as well. Often contains a supplemental card or booklet on the enclosed DVD title.

The first videophile format, launched way back in the '80s, delivered an analog signal from a disc the size of an LP. Very good for the time (and still superior to videotape), but never a mass-market success. However, there are still some Laserdisc holdouts who claim that the format is superior to DVD and the MPEG-2 process. We have a Laserdisc player as part of our review equipment, and we respectfully disagree. Only poorly compressed DVDs from 1997 and 1998 could be considered inferior to Laserdisc, and source-materials rarely were cleaned up for Laserdisc release.

Laser rot
Even though Laserdisc is not a contact format (i.e., nothing touches the moving disc except a laser), it has been shown that they can deteriorate over time, although this may only be due to poor handling. This has been dubbed "laser rot," and while many folks assure us that this phenomenon will not happen to DVD, there simply hasn't been enough time yet to determine the matter one way or the other.

Layer switch

Letterbox, Letterboxing
See aspect ratio

Acronym for "low-frequency effects," a special channel in Dolby Digital (the ".1" of the 5.1) that delivers limited-bandwidth bass. The LFE channel should be reproduced with a quality subwoofer. See also Dolby Digital.

Macrovision is a proprietary technology designed to defeat video piracy by interfering with attempted copying of Macrovision-protected media. As such, it's really popular with the major studios and other home-video companies, all of whom would rather you just put those RCA cables away. If you try to copy Macrovision-protected material, you will notice that the resulting picture will be skewed and fade from overly light to very, very dark. Macrovision does not alter the audio signal.

Macrovision can be defeated with a "Macrovision-buster," a device manufactured by numerous electronics-geeks that will modulate or eliminate the interfering signal (your mileage will vary). Some people purchase Macrovision-busters because they claim that the technology interferes with their perfectly legal home-video enjoyment. This may or may not actually be legal, so don't ask us about it. However, it is likely that the vast majority of people who own Macrovision-busters are illegally copying DVDs and videotapes.

A monaural audio signal, meaning one signal for one or more speakers. Some DVDs state the audio is in two-channel mono, but that ain't stereo folks. That just means you can play the mono track on the two front speakers to create a wider soundstage. Often called "1.0" in HT parlance.

The video-coding system (based on a compression algorithm) that permits films and other entertainment to be placed on DVD. An MPEG-2 signal, when mastered properly, delivers a superior video signal.

Acronym for "Pulse-code modulation," and the digital standard for Compact Disc audio, the uncompressed data that offers us pristine digital sound when we listen to music with our CD players. PCM/Compact Disc is probably the most radical, successful, and valuable home-entertainment technology yet offered to consumers, although DVD Video may soon rival it, and MP3 appears to be the revolutionary audio format of the 21st century. See also DVD Audio.

Remember when you were 14 and discovered RCA cables? Seemed harmless right? Well, the home-video companies probably didn't care about you anyway. However, international video piracy for profit is a major concern of all Hollywood studios and is one of the reasons that many of them, such as Paramount and Fox, stayed away from DVD for so long, since the digital code of DVD movies could be theoretically (and now practially, with DeCSS) pirated without any degradation, unlike the analog signal of videotapes, which will corrupt with duplication. We recommend that you don't buy any illegal DVDs, since this consumer behavior could impede the release of movies on DVD in years to come. Besides, pirated DVDs are notoriously worse than legal videotapes, and often more expensive.

Port, ported
A speaker-case design that utilizes a hole in the case for better acoustic effect. Virtually all quality speaker-cases are ported. If your speakers don't have holes they are considered "sealed."

The celluloid film that captures and projects movies, and is notoriously difficult to keep in good shape. Prints (especially color prints) will fade over time and need restoration, which is also a notoriously difficult (and expensive) process. Because of these issues, and a lack of foresight that was necessary to preserve older films, many classics may be lost beyond repair. Print restorations do happen (Vertigo and Gone with the Wind to name two), but consumer demand is not sufficient enough to ensure that all of our favorite movies will be saved. While many would say that films in digital format are inferior to projections on a silver screen, committing films to DVD is one step in the process to ensure that they will have a much longer lifespan, if only on video projectors.

Pro Logic
See Dolby Pro Logic

Rear-projection television
Larger televisions screens, above 36" or so, are commonly of rear-projection design, wherein the cathode-ray tube is eliminated and the video signal is transmitted from inside the set and onto the back of a screen. The resulting image can be difficult to see if there is ambient light in the room.

Region Coding
It works a little something like this: Hollywood studios do not release all of their films at the same time around the world. While you are enjoying a brand-new DVD in your home theater, the movie you are watching may not have opened yet in, say, Taiwan, or Bucharest, or Santiago. In order to protect their worldwide release schedules from international orders of DVDs, which would eat into theatrical profits, when the DVD standard was invented the studios asked for "region-coded" discs that would play on region-coded machines. If you are in North America, you own a "Region 1" player and Region 1 discs, whereas consumers in Europe own Region 2 hardware and discs.

This issue is rarely bothersome for Region 1 consumers because they always get their DVDs first (with rare exceptions). Consumers in other regions, however, don't like region coding when they can get Region 1 discs shipped to them. This has led to a proliferation of "code-free" DVD players, which have been altered after the sale to play all DVDs. This may or may not be legal -- we have no comment.

There are six DVD regions. Discs that have been released with no region coding are said to be "Region 0" (zero).

The process of returning the original celluloid print of a film to its original pristine condition. See also Print.

Acronym for "reverse spiral, dual layer," a feature of the DVD format that allows two layers of information to be placed on one side of the disc, with the top layer being transparent. When the laser moves from the top layer of the disc to the bottom, the player may pause briefly. This is called the layer switch, and some are so good you don't know they are there. However, some layer switches are distracting and not well done. An RSDL disc (a type of DVD-9) is gold in color, whereas a single-layered disc has a silver hue. Before the first RSDL disc (Terminator 2), movies longer than about two hours were split across two sides of the disc, which required that the disc be ejected and re-inserted on the other side. As such, they were nicknamed "flippers." Many flippers are still in release, but they are no longer widely manufactured.

See Faroudja

Acronym for "Sony Dynamic Digital Sound," a discrete multi-channel audio system for theatrical films. As of yet, Sony has not announced that SDDS will appear in a consumer format for home theater, and as of this writing they have no plans to do so.

Breakup of the picture on DVD which results in an undefined image that "wobbles" across textures or angled lines. A result of poor mastering. See also Transfer.

See Warner snap-case.

Spend a lot of money on these. Along with the source material (i.e., a quality CD or DVD), the speakers are the most important part of your home-theater audio system, and you should spend at least twice as much on them as you paid for your bitchin' HT amplifier (i.e., $600 amp = $1,200 for speakers, if not more).

In HT parlance, 2.0, which means two speakers delivering discrete audio signals. My dad thought 2.0 was very cool back in the mid-'60s.

Essentially, a big-ass ported speaker that conveys low-frequency effects and also can add some rumble to your home theater. The LFE channel in a Dolby Digital or DTS mix is designed for a subwoofer.

Abbreviation of "Subwoofer/Satellite," an HT speaker system comprising five "satellite" speakers, which are small and often not full-range, and a subwoofer for bass. Also called "home theater in a box" at many retailers. A sub/sat system can produce pleasing results, but they are inferior to most full-range HT speaker systems, and sometimes cost more, not less. One well-known sub/sat manufacturer sells HT audio systems that cost in the thousands of dollars.

A set of cinema and home theater standards owned by and implemented by George Lucas' Lucasfilm company. Cinematic theaters with THX are of high quality, but if you intend to do your entire home theater to the THX standard, plan on spending a lot of money. See also THX Surround EX.

General term that refers to the process of committing a film to DVD via MPEG-2 coding (for the video) and a Dolby variant or DTS ( for the audio). When a movie looks good on DVD, it is said to have a "good transfer." Bad transfers can result in artifacts, shimmer, or audio drop-outs.

Warner Home Video
The virtual founder of DVD movies, for were it not for Warner Home Video and their aggressive promotion of DVD in 1997, other studios may have gotten cold feet and DVD would have gone the way of Betamax, if it ever got that far.

Warner snap-case
A DVD case manufactured by Warner Home Video that uses a paperboard shell and a durable plastic "snap" enclosure. Less popular with DVD collectors than the keep-case, and primarily used on Warner Home Video releases (Warner, New Line, HBO, and early MGM titles), along with most Image titles. Commonly called a "snapper." Phased out by Warner Home Video in 2004.

See Aspect ratio

Impossible to define. See also A/V.

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