DVD Frequently Asked Questions
What is DVD?
What Are The Different DVD Formats?
Packaging and Casing
What are the features of DVD Video?
What is Regional Encoding?
What is Regional Coding Enhancement?
Why is there a difference between the running time of PAL and NTSC films?
What is Aspect Ratio?
What is Fullscreen?
What is Widescreen?
What is Anamorphic Widescreen?
Dolby Digital vs Dolby Surround?
What is DTS?
What Is Superbit?
DVD stands for Digital Versatile Disc and it is the latest means of storing information on optical media. In essence it is a bigger faster CD that can hold various information, from video and audio to computer data. DVD aims to replace several different forms of digital media with a single digital format, eventually replacing Audio CD, Videotape, Laserdisc and CD Rom.
DVD has widespread support from all major electronics companies, all major computer hardware companies, and all major movie and music studios. With this unprecedented support, DVD has become the most successful consumer electronics product of all time in less than three years of its introduction.
Unlike CDs, DVDs can store data on either side of the disc, while also allowing two layers of data per side. Four combinations are available, with the number depicting the amount of gigabytes that can be stored on the disc: DVD-5 - single-layered single-sided, DVD-9 - dual-layered single-sided (currently the most common), DVD-10 - single-layered double-sided, and DVD-18 - dual-layered double-sided.
There are three basic types of DVD cases. Amaray cases are solid coloured or transparent plastic. Jewel cases (formerly called CD cases, because they look like cases for their audio counterparts) are clear plastic. Snapper cases are made of cardboard with a plastic fastener that clicks closed (hence the name). You will also find that some titles, particularly multi-disc box sets, will be packaged in specifically designed custom cases. We list the case type on all of our new comparisons and are adding them to the older titles as fast as we can.
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Over 2 hours of high-quality digital video (a double-sided, dual-layer disc can hold 8 hours of high-quality video, or 30 hours of VHS quality video).
Support for widescreen movies on standard or widescreen TVs (4:3 and 16:9 aspect ratios).
Up to 8 tracks of digital audio (for multiple languages etc.), each with as many as 8 channels. Up to 32 subtitle/caption tracks.
Automatic 'seamless' branching of video (for multiple story lines or ratings on one disc).
Up to 9 camera angles (different viewpoints can be selected during playback although this feature is not currently utilised on many discs).
Menus and simple interactive features (for games, quizzes, etc.).
Multilingual identifying text for title name, album name, song name, cast, crew, etc.
Instant rewind and fast forward (no 'be kind, rewind' stickers and threats on rental discs)
Instant search to title, chapter, music track, and timecode.
Durable (no wear from playing, only from physical damage).
There are 6 Regions assigned to the release of DVDs worldwide. Why?
It is not in the studio's best interest to release a DVD title simultaneously to a worldwide marketplace, as the theatrical release date of a film varies from country to country - this in itself is a topic for much discussion! Therefore, one country's DVD releases often occur close to another countries theatrical release date.
To stop consumers from watching DVDs prior to their country's theatrical release date, regional coding has been imposed.
The regions are:
Region 0: No Restriction: Worldwide availability, plays on all machines.
Region 1: Canada, USA, US Territories.
Region 2: Europe, Middle East (including Egypt).
Region 3: Southeast Asia, East Asia (including Hong Kong).
Region 4: Central America, South America, Mexico, Australia, New Zealand, Pacific Islands, Caribbean.
Region 5: Russian Federation, Africa (not Egypt), North Korea, Mongolia.
Region 6: China.
There are also two other, commercially unavailable Region codes:
Region 7: Reserved. Often used for airlines.
Region 8: Reserved.
Therefore originally, a European consumer who purchased hardware in Europe, would only be able to obtain playback on Region 2 discs. This was so for the first few players available on the market when DVD first became available. The fast pace of technological change has since brought about multi-region players and hardware hacks, allowing consumers to playback discs purchased from other regions.
It is commonly known that many manufacturers of older 'European' Region 2 DVD players can 'chip' or bypass the regional coding, thus permitting the customer to play any disc. The same modification can also be achieved on some players by using a simple 'software hack' via the player's remote control. Check here for more details about your particular player.
At DVD Compare we cater for a worldwide market focusing particularly on American Region 1 discs, British Region 2 discs and Australian Region 4 discs.
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The latest effort on the studios behalf to halt the usage of multi region players was to introduce 'RCE: Regional Coding Enhancement'
Columbia Tristar and Warner are the first studios to implement this system, but have not issued any official press releases on the subject of RCE. Also, it is important to note that not all DVD titles from these studios will be affected.
The first titles to utilise this enhancement on Region 1 discs include 'The Patriot: Special Edition', 'A Perfect Storm', 'Hollow Man' and 'All The Pretty Horses'. However, hardware manufacturers are finding ways around this problem and some brands are not affected.
Region Coding Enhancment is a signal of Region 2 coding on a Region 1 disc that brings up a screen on multi-region or modified Region 2 players, which may halt the continuing playback of Region 1 material dependent on your hardware. RCE coding allows a disc to detect if a player is 'multi-region' or if a Region 2 player has been altered to playback Region 1 discs. The message that will be displayed on screen is as follows:
"THIS DVD PLAYER MAY HAVE BEEN ALTERED AND IS UNABLE TO PLAY THIS DISC. THERE IS NOTHING WRONG WITH THIS DISC. DVD PLAYERS AND DISCS ARE DESIGNED TO WORK IN CERTAIN REGIONS. THIS DISC IS NOT COMPATIBLE WITH THIS PLAYER. PLEASE CONTACT YOUR LOCAL RETAILER OR PLAYER MANUFACTURER FOR ADDITIONAL INFORMATION. WE APOLOGIZE FOR ANY INCONVENIENCE".
If you are unsure if your multi-region or modified Region 2 player will allow playback, we would like to advise you not to purchase any disc which is marked as 'RCE'. Wherever possible we will make a note on our comparisons if an RCE disc is involved but please bear in mind that this information may not be available at the time that the comparison details are input.
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Due to a difference in the frame rate between NTSC and PAL releases there will be a slight difference in the running time of the DVDs across the formats. The difference will be approximately 4% so a feature with a US NTSC Region 1 running time of 100 minutes will be shortened to 96 minutes when transfered to UK PAL Region 2. This is completely normal and no scenes have been removed.
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The numbers for the aspect represent the ratio for the width of a fullscreen or widescreen format in relation to its height. The standard television picture is 4 units wide by 3 units high or ratio 4:3, this is also expressed as 1.33:1 meaning that the width is one and third times the size of the height. It is this second, decimal, method which is used the most.
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Fullscreen is the standard Aspect Ratio for television (4:3 or 1.33:1), which means that the width of the screen is precisely one and a third more than the height. Fullscreen films fill the entire screen area of normal televisions and if they are played on widescreen televisions, you will see black bars on each side (right and left) of the screen.
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A widescreen television has an Aspect Ratio of 16:9 (or 1.78:1). Widescreen is the original size of the theatrical presentation, filmed in various aspect ratios, the format was first introduced around 1950.
In widescreen 'Letterboxed' versions it is normal to see a black strip at the top and bottom of the screen, although its thickness depends on the aspect ratio. The only exception is that if the picture is mastered in the ratio 1.78:1 when the widescreen will be filled.
Two of the most common aspect ratios are 1.85:1 and 2.35:1 which measure the width of the picture in relation to its height. Therefore, the wider the screen (or higher the decimal number), the thicker the black bars will be.
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The 'Anamorphic Widescreen' technique allows for a superior picture quality, without altering a film's aspect ratio. Knowledgeable DVD buyers often demand it. Consumers new to DVD and even old enthusiasts are still confused by the technology.
Various catchphrases will often be mentioned on the DVD Cases - 'enhanced for 16x9 televisions', 'widescreen 16x9' and '16x9 anamorphic' - these all mean that the disc has been encoded with 'anamorphic widescreen'.
When a DVD says that it is anamorphic, it means that the film has been transferred onto the disc with extra vertical scan lines (a higher resolution), making it ideally suited to playback on a widescreen TV. During playback, the information 'unsqueezes' to stretch across the wide screen, and thanks to those extra lines, the vertical part of the image doesn't lose clarity.
Anamorphic films will always look better on widescreen televisions. Regular TVs will display the widescreen picture as usual, in a letterbox format and ignoring the extra lines, but can occasionally throw up digital artifacts (blocky chunks of colour).
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Dolby Digital vs Dolby Surround?
'Dolby' is a proprietary audio coding technique used in 'analog' formats, developed by Dolby Laboratories for storing and transmitting single or multiple channels of audio. The term 'Dolby' often causes confusion among consumers purchasing DVD discs, as the studios, producers, suppliers, distributors, back cover artwork and retailers describe older DVD discs (or new releases of classic movies) as having 'Dolby' audio. Almost all DVDs contain audio in Dolby Digital format, not analogue; every DVD player contains a Dolby Digital decoder.
'Dolby' formats that you may find listed in the "Sound" section of a DVD's technical details are listed below.
(1.0) Contains only one channel of recorded audio.
(2.0) Contains two channels of recorded audio.
(4.0 or 2.0) Dolby Surround is the consumer version of the original analog Dolby multichannel film sound format. When a Dolby Surround soundtrack is produced, four channels of audio information - left, centre, right, and surround - are encoded onto two audio channels. These two tracks are then carried on stereo program sources, where they can be processed by a Dolby Surround Pro Logic decoder (now standard in most home theatre systems and components) to recreate the original four channels and the surround sound experience.
Surround (Pro Logic)
Dolby Pro Logic is a decoding technology and the successor to Dolby Surround, containing an added dialogue channel.
In the beginning, Dolby Surround decoders simply fed the entire program in normal stereo to front left and right speakers, and the surround signal derived by a simple passive matrix decoder to the surround speakers.
Dolby Surround Pro Logic decoding was then developed which, like professional Dolby film processors, actively derives a separate centre channel to keep dialogue and other central sounds firmly localized on the screen for all viewers, even those off to the sides. Dolby Pro Logic also supplies higher separation among all four channels for more accurate sound positioning. As a result of its higher performance and steadily decreasing cost, Dolby Pro Logic today is standard in virtually all home theatre systems and components.
Dolby Digital Mono
(1.0) Contains only one channel of recorded digital audio.
(2.0) This format will seem a little confusing at first. Two Channel Mono plays one language from the left speaker, whilst it can also play another language from the right. Allowing discs with mono recordings to have multiple language tracks.
Dolby Digital Stereo
(2.0) Contains two channels of recorded digital audio played into a left and right speaker.
Dolby Digital (Surround)
(3.0) describes the configuration of one left and right front channel, as well as one centre channel encoded discretely.
(5.0) describes the standard discrete surround-sound configuration of three full-range front channels and two-full range surround channels.
(5.1) describes the standard discrete surround-sound configuration of three full-range front channels, two-full range surround channels, and a bass-only low-frequency effects channel.
DTS (Digital Theater Systems) is a different digital audio format also offering 5.1 channels of surround sound abilities, and has been added to the DVD specification as an optional audio format. Some experts say that it sounds better because there is less compression than Dolby Digital, but on most home systems it would be hard to tell the difference. Whether it's better or not, there are only a handful of Region 2 DTS-encoded DVDs available at the moment, although the number is increasing slowly.
Although DTS offers more realistic audio, the soundtrack does take up more space on a disc compared to a Dolby Digital Soundtrack. However, there is still ample space available on the disk to add such features as trailers, commentaries and documentaries.
Unfortunately some DTS-encoded DVDs may be released with fewer (or different) extras than the non-DTS versions. This is simply the decision of the producer of the disc, and not usually the result of space limitations.
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Superbit is a type of disc issued by Columbia Tristar Home Entertainment whereby DVDs do not have special features in order to save room on the disc for the best possible sound and video format.
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