DVD Glossary (ever growing and ever changing!)

16:9 enhanced - see 'Anamorphic'

Anamorphic - Well, it's exact meaning is unclear, but basically it is a method for enhancing the vertical resolution of a picture stored on DVD which can then be displayed at a higher resolution on an anamorphic-compatable display device. This is a complex beast and I recommend visiting World's Easiest Explanation of Anamorphic 16:9 Widescreen Enhancement in DVDs.

Component Video - A type of video connection used for input/output of a video signal. It can provide picture quality superior to S-Video connections,with the signal passed via three cables from the source to the destination. This type of connection is usually found on high-end equipment, so if your TV and DVD player support it then definitely use this over S-video.

Composite Video - The standard connection and most common way to transfer a video or audio signal. Almost all A/V products have this type of connection, with the more expensive equipment having the more advanced connections as well such as S-video or component . Three cables (coloured yellow, red and white) are used for transferring the video signal (yellow) and the two audio channels Left & Right are passed through the white and red cable.

DIVX - Digital Video Express - now this is a hot topic. It's a competing format against DVD in the USA. See DiVX for the pro and see just about any other site for the cons.

Dolby Digital - This is the main format the audio is stored onto DVD. It is a compression technique capable of storing from 1 to 6 channels of discrete sound information in a limited bandwidth. See Dolby Labs

Dolby Prologic - This is the surround sound format from Dolby Labs before dolby digital. It is still found in many places and analog sources such as VHS tapes still carry it as the highest available surround sound format. Prologic is produced by taking the two channel source audio track and extracting the center and surround information from it. While the surround sound effect is adequate it is far less effective and spectacular than Dolby Digital. All Dolby Digital receivers are capable of playing back Prologic tracks but older prologic receivers cannot play Dolby Digital. However if your Prologic receiver has a 5.1 input then an external Dolby Digital decoder (such as an on board DVD player decoder) can decode the DD 5.1 signal and pass it through the inputs, allowing the Prologic receiver to play full Dolby digital. see Dolby Labs

DTS - Digital Theater Systems have released a competing audio format to Dolby Digital, claiming clearer, better sound. This requires a speacial DTS-capable DVD player to output. see DTS-Online

DVD - Originally stood for 'Digital Versatile Disc', but more commonly referred to (for now anyway) as 'Digital Video Disc' due to the high profile movies have on this format and the low use of DVD-ROM style content.

Laserdisc - Before DVD there was laserdic. This large (12") optical disc, is about the size of an LP record but it is optical instead. Each disc holds audio and visual information like DVD, but each side is limited to only 60 minutes thus forcing most movies to be spanned over two sides and often over another disc as well. This was a big drawback, requiring the viewer to interrupt their viewing 2-3 times per movie. LD has same similar features to DVD, but not in the same quantity or quality that DVD offers. LD was the standard among movie afficionados looking for the best picture/audio available. Ever since DVD arrived though, LD has started to die and many collector's no longer add to their laserdisc libraries (A LD is considerably more expensive than an equivalent DVD).

MPEG - Moving Pictures Expert Group - the people who came up with the compression techniques used in acheiving the incredible amount of data onto a DVD. see MPEG.ORG

NTSC - This is the format used mainly in the United States for encoding of video signal. It provides refresh rates of 60 Hz and vertical resolution of approx. 425 lines.

PAL - This is the format used mainly in Australia and parts of Europe for encoding of video signal. It provides refresh rates of 50 Hz and vertical resolution of approx 525 lines.

Region-coding - The Hollywood movie studio's decided to break the world into 6 regions for DVD video distribution. Australia is designated as region 4, the USA and Canada is region 1, Europe is region 2, China is region 6 etc. If you buy a player is Australia it will only play region 4 titles. Buy a player is the USA and it only plays region 1 titles. You get the idea.

THX - Probably THE most misunderstood term in the Home Theatre glossary. There are many that wrongly believe that THX is an audio and video format (like Dolby Digital) that provides higher quality sound and video. This is incorrect. THX is actually NOT a sound format. It is a set of standards set by Lucas Film to ensure the highest possible quality of video and audio. Only those that meet these standards are allowed to place the THX logo on their equipment/cinemas.
This is an extract from Lucas Film about THX:

The THX Sound System was developed in 1982 during the production of Return of the Jedi. Inspired by George Lucas' interest in upgrading film presentation standards in the industry, Lucasfilm's Corporate Technical Director, Tomlinson Holman, began to identify problems related to theatre sound. Holman noted theatre audiences were not hearing what was recorded in the film studio - many of the subtle sounds were missing. His innovative approach was to consolidate existing performance standards into a new system which included theatre acoustics as well as sound equipment. THX (named after Lucas' first feature film, THX 1138) is a sound system designed specifically to reproduce film sound exactly as it was recorded by the filmmaker.

The THX Sound System is the only program of its kind to consider all aspects of a theatre's audio & visual performance, including architecture, acoustics and equipment. "THX is really a performance criteria; it's not a specific set of components," says Holman. The system was created to complement advances made by Dolby Laboratories in decoding sounds in the sound track which concentrates on the "A-Chain." The THX Sound System concentrates on the "B-Chain" of a theatre's sound system. The "B-Chain" is comprised of customized acoustical design work for each auditorium, a special screen speaker installation method, a proprietary electronic crossover network, and rigorous audio equipment specifications and performance standards. Upon completion of a THX Sound System installation, the theatre is tested by a THX engineer to make sure it meets both THX environmental technical criteria and recommended industry standards for high quality visual and sound presentation. Theatres are recertified to ensure that optimum quality is maintained.

A certified THX theatre carries several important advantages for the movie-goer. The audience enjoys a more naturally balanced sound that uniformly reaches every seat in the auditorium, improved dialog intelligibility and decreased bass distortion. Better stereo localization makes the sound appear to travel across the screen with action. A frequency range that is wider by a full octave in both bass and treble allows patrons to hear higher highs and lower lows. The combined result is the reproduction of the same clear, dynamic sound originally created by the filmmaker.

The exhibitor's unique challenge is to create an environment that keeps the magic of the big screen alive. With installations in more than 1400 certified THX theatres and dubbing facilities worldwide, the THX Sound System has become the premium standard for quality film presentations.

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