This is the June 27, revision of the official Internet DVD FAQ for the rec. See below for what's new. This FAQ is usually updated at least once a month. If you are looking at a version more than a few months old, it's probably an out-of-date copy. The most current version is at DVD Demystified.

For the absurdly curious, here's the list of changes stretching back into the mists of time. The following translations of the DVD FAQ are available. Translations to a few other languages are in progress. If you'd like to translate the DVD FAQ into another language Klingon, anyone? Take a gander at Earl's Famous DVD Technology Exposition Web Page Extravaganza Supreme Deluxe.

Although Lisa erroneously claims DVD stands for "digital versatile disc" -- who you gonna believe, me or an 8-year old genius? Here are a few user comments on the DVD FAQ. If you type "DVD" into Google, this Web site is often the 1 result. It's the most accurate source of DVD information in this galaxy.

If you find something you think is in error, please let Jim know. There's plenty of other good information about DVD on the Internet. Pointers to other DVD sites are scattered throughout the FAQ and in section 6. The DVD FAQ is written by Jim Taylorthe author of DVD DemystifiedEverything You Ever Wanted to Know About DVDand Blu-ray Disc Demystified.

Jim has been in the DVD business since before there was a DVD business. In he found out about the upcoming DVD format and began writing articles to let others know about this amazing new technology. Jim received the DVD Pro Discus Award for Outstanding Contribution to the Industry, was named one of the 21 most influential DVD executives by DVD Report, was an inaugural inductee into the Digital Media Hall of Fame, and was named one of the Pioneers of DVD in the October issue of One to One magazine.

Jim has worked with interactive media for over 25 years, developing educational software, laserdiscs, CD-ROMs, Web sites, and DVDs, along with teaching workshops, seminars, and university courses. Jim was formerly DVD Evangelist at Microsoft, and is currently Chief Technologist at Sonic Solutionsthe leading developer of DVD and BD creation software. If you're wondering why it's all in one big piece instead of broken into smaller pieces that would load faster, the main reason is so you can use the find feature of your browser to easily search the entire FAQ.

I realize this causes problems with WebTV browsers.

I might break it up some day. DVD is movies on a shiny disc, and much more. It's an optical disc storage technology for video, audio, and computer data. DVD is essentially a bigger, faster CD that can hold high-quality digital video, better-than-CD audio, pictures, and any other sort of digital information. DVD encompasses home entertainment, computers, and business information with a single digital format.

It replaced laserdisc, videotape, many video game cartridge formats, and many CD-ROM applications. 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 became the most successful consumer electronics product of all time in less than three years of its introduction. Inten years after launch, there were over one billion DVD playback devices worldwide, counting DVD players, DVD PCs, and DVD game consoles.

It's important to understand the difference between the physical formats such as DVD-ROM and DVD-R and the application formats such as DVD-Video and DVD-Audio. DVD-ROM is the base format that holds data. DVD-Video often simply called DVD defines how video programs such as movies are stored on disc and played in a DVD-Video player or a DVD computer see 4. The difference is similar to that between CD-ROM and Audio CD. DVD-ROM includes recordable variations: There are also special application formats for game consoles such as Sony PlayStation 2 and Microsoft Xbox.

And the official answer is A report from DVD Forum Steering Committee in decreed that DVD, as an international standard, is simply three letters. Nevertheless, Toshiba — the maintainer of the DVD Forum Web site — still confusingly prefers "digital video disc.

No one agrees on that one either. Some discs may not allow searching or skipping. DVD has the capability to produce near-studio-quality video and better-than-CD-quality audio. DVD is vastly superior to consumer videotape and generally better than laserdisc see 2. However, quality depends on many production factors. As compression experience and technology improves we see increasing quality, but as production costs decrease and DVD authoring software becomes widely available we also see more shoddily produced discs.

A few low-budget DVDs even use MPEG-1 encoding which is no better than VHS instead of higher-quality MPEG DVD video is usually encoded from digital studio master tapes to MPEG-2 format. The encoding process uses lossy compression that removes redundant information such as areas of the picture that don't change and information that's not readily perceptible by the human eye.

The resulting video, especially when it is complex or changing quickly, may sometimes contain visual flaws, depending on the processing quality and amount of compression. At average video data rates of 3. Higher data rates can result in higher quality, with almost no perceptible difference from the master at rates above 6 Mbps. As MPEG compression technology improves, better quality is being achieved at lower rates. Video from DVD sometimes contains visible artifacts such as color banding, blurriness, blockiness, fuzzy dots, shimmering, missing detail, and even effects such as a face that "floats" behind the rest of the moving picture.

It's important to understand that the term "artifact" refers to anything that is not supposed to be in the picture. Artifacts are sometimes caused by poor MPEG encoding, but artifacts are more often caused by a poorly adjusted TV, bad cables, electrical interference, sloppy digital noise reduction, improper picture enhancement, poor film-to-video transfer, film grain, player faults, disc read errors, and so on.

Most DVDs exhibit few visible MPEG compression artifacts on a properly configured system. If you think otherwise, you are misinterpreting what you see.

Some early DVD demos were not very good, but this is simply an indication of how bad DVD can be if not properly processed and correctly reproduced. In-store demos should be viewed with a grain of salt, since most salespeople are incapable of properly adjusting a television set. Most TVs have the sharpness set too high for the clarity of DVD. This exaggerates high-frequency video and causes distortion, just as the treble control set too high on a stereo causes the audio to sound harsh.

For best quality the sharpness control should be set very low. Brightness should also not be set too high. Some DVD players output video with a black-level setup of 0 IRE Japanese standard rather than 7. On TVs that are not properly adjusted this can cause some blotchiness in dark scenes. There may be an option in the player menu to use standard black level. DVD video has exceptional color fidelity, so muddy or washed-out colors are almost always a problem in the display or the original sourcenot in the DVD player or disc.

DVD audio quality is superb. DVD includes the option of PCM pulse code modulation digital audio with sampling sizes and rates higher than audio CD. Alternatively, audio for most movies is stored as discrete, multi-channel surround sound using Dolby Digital or DTS audio compression similar to the digital surround sound formats used in theaters.

As with video, audio quality depends on how well the processing and encoding was done. In spite of compression, Dolby Digital and DTS can be close to or better than CD quality.

Some manufacturers originally announced that DVD players would be available as early as the middle of These predictions were woefully optimistic. Delivery was initially held up for "political" reasons of copy protection demanded by movie studios, but was later delayed by lack of titles. The first players appeared in Japan in November,followed by U. Players slowly trickled in to other regions around the world. Six years after the initial launch, close to one thousand models of DVD players were available from over a hundred consumer electronics manufacturers see 6.

Fujitsu supposedly released the first DVD-ROM-equipped computer on Nov. Toshiba released a DVD-ROM-equipped computer and a DVD-ROM drive in Japan in early moved back from December which was moved back from November. DVD-ROM drives from Toshiba, Pioneer, Panasonic, Hitachi, and Sony began appearing in sample quantities as early as Januarybut none were available before May.

The first PC upgrade kits a combination of DVD-ROM drive and hardware decoder card became available from Creative Labs, Hi-Val, and Diamond Multimedia in April and May of Today, every major PC manufacturer has models that include DVD-ROM drives. For more information about DVDs on computers, including writable DVD drives, see section 4. If you buy a player or drive from outside your country e. The first DVD-Audio players were released in Japan by Pioneer in latebut they did not play copy-protected discs.

DVD-Audio players are now also made by Aiwa, Denon, JVC, Kenwood, Madrigal, Marantz, Nakamichi, Onkyo, Toshiba, Yamaha, and others. Pioneer's first DVD-Audio players released in late also played SACD. SACD players are now also made by Accuphase, Aiwa, Denon, Kenwood, Marantz, Philips, Sharp, and others. There are many good players available.

Video and audio performance in all modern DVD players is excellent. Personal preferences, your budget, and your existing home theater setup all play a large role in determining which player is best for you.

Then try out a few of the players in your price range, focusing on ease of use remote control design, user interface, front-panel controls.

Since there is not a big variation in picture quality and sound quality within a given price range, convenience features play a big part. The remote control, which you'll use all the time, can drive you crazy if it doesn't suit your style. Some players, especially cheaper models, don't properly play all discs. Before buying a player, you may want to test it with a few complex discs such as The MatrixThe AbyssIndependence Dayand DVD Demystified. In certain cases, you might want to buy a DVD PC instead of a standard DVD player, especially if you want progressive video.

For more information, read hardware reviews at Web sites such as DVDFile or in magazines such as Widescreen Review. You may also want to read about user experiences at Audio Review and in online forums at Home Theater Forum and DVDFile.

There's more advice at DVDBuyingGuide and at eCoustics. Titles are collectively referred to as software, not to be confused with computer software. DVD started off slowly. Rosy predictions of hundreds of movie titles for Christmas of failed to materialize. Only a handful of DVD titles, mostly music videos, were available in Japan for the November launch of DVD.

The first feature films on DVD appeared in Japan on December 20 The Assassin, Blade Runner, Eraser, and The Fugitive from Warner Home Video. By April, there were over titles in Japan. The first titles released in the U. An Adventure of a Different Nature, Tropical Rainforest, and Animation Greats.

Other movies such as Batman and Space Jam had been demonstrated earlier, but were not full versions available for sale. Almost 19, discs were purchased in the first two weeks of the US launch -- more than expected.

InfoTech predicted over titles by the end of and more than 8, titles by By Decemberover 1 million individual DVD discs were shipped, representing about titles. By the end ofover million discs had shipped, representing about 5, titles. By the end of there were over 10, titles available in the US and over 15, worldwide. By the end of there were about 14, titles available in the U.

By the end of there were about 23, titles available in the U. By Marchsix years after launch, over 1. Compared to other launches CD, LD, etc. Just over 10, new DVD titles were released inand almost 11, came out infor a total of 42, titles with about 40, still available. A number of DVD launches in Europe were announced with little follow-through, but DVD began to become established in Europe around the end of Availability of DVDs in Europe was initially about 18 months to a year behind the U.

DVD-Audio started even slower than DVD-Video. The first commercially available DVD-Audio title, Big Phat Bandwas released in October on the Silverline label of 5. Major music labels BMG Entertainment, EMI Music, Universal Music, and Warner Music have committed to DVD-Audio titles, although in fall Universal announced that it would release SACD titles first. As of the end ofjust under DVD-Audio titles were available. The first SACD titles were released in Japan in May DVD-ROM computer software is slowly appearing.

Many initial DVD-ROM titles were only available as part of a hardware or software bundle. IDC predicted that over 13 percent of all software would be available in DVD-ROM format by the end ofbut reality didn't meet expectations.

In one sense, DVD-ROMs are simply larger faster CD-ROMs and contain the same material. In many cases CD-ROMs are big enough that there's no need to move to DVD-ROMs.

But DVD-ROMs can also take advantage of the high-quality video and multi-channel audio capabilities being added to many DVD-ROM-equipped computers.

The following sites have reviews of at least discs. Also see the list of DVD review sites at Yahoo. First, check one of the lists and databases mentioned in 1. There's also the release list at Image Entertainment. A good source of info about unannounced titles is The Digital Bits Rumor Mill. There are many factors that determine when a title is released on DVD. Other times it's up to the studio marketing group. Often there are issues with rights. For example, a DVD might be available in one country or region but not available in another because different studios have distribution rights in different countries.

Studios do listen to customers, so let them know what titles you'd like to see see 6. Use one of the searchable databases in 1. Select the features you're looking for anamorphic widescreen, French audio track, Flemish subtitles, and so on.

If a database doesn't include the characteristic you're looking for, try a different database. Some rental chains such as Blockbuster and retailers such as Wal-Mart originally carried only fullscreen pan and scan versions of movies when both widescreen and fullscreen versions were available.

This infuriated many DVD fans, who could never countenance watching a non-widescreen version of a movie on DVD. There was much complaining, including an online petition with over 25, signatures. In early Blockbuster reversed their policy with the following statement: We try to follow our customer preferences. As DVD becomes increasingly popular, they become more familiar with the features and with the benefits of letterboxing.

They've learned it's a superior format to full-frame. DVDs have not followed the initial high-rental-price model of VHS. DVD-ROMs are usually slightly more expensive than CD-ROMs since there is more on them, they cost a bit more to replicate, and the market is smaller.

But as the installed base of drives grow, DVD-ROMs will eventually cost about the same as CD-ROMs do today. DVD did not take off quite as fast as some early predictions, but it has sold faster than videotape, CD, and laserdisc. In fact, before its third birthday in MarchDVD had become the most successful consumer electronics entertainment product ever.

For comparison, there were about million audio CD players and million CD-ROM drives worldwide in There were about 80 million VCRs in the U. Nearly 16 million VCRs were shipped in In there were about million TVs in the U. When DVD came out in there were under 3 million laserdisc players in the U. Other DVD statistics and forecasts can be found at IRMAMediaLineTwice. Motion picture studios want to control the home release of movies in different countries because theater releases aren't simultaneous a movie may come out on video in the U.

Also, studios sell distribution rights to different foreign distributors and would like to guarantee an exclusive market. Therefore they required that the DVD standard include codes to prevent playback of certain discs in certain geographical regions.

Each player is given a code for the region in which it's sold. The player will refuse to play discs that are not coded for its region. This means that a disc bought in one country may not play on a player bought in another country. Some people believe that region codes are an illegal restraint of trade, but no legal cases have established this.

Regional codes are entirely optional for the maker of a disc. Discs without region locks will play on any player in any country. It's not an encryption system, it's just one byte of information on the disc that the player checks. Some studios originally announced that only their new releases would have regional codes, but so far almost all Hollywood releases play in only one region. Region codes are a permanent part of the disc, they won't "unlock" after a period of time.

Region codes don't apply to DVD-Audio, DVD-ROM, or recordable DVD see below for more detail. Seven regions also called locales or zones have been defined, and each one is assigned a number. Players and discs are often identified by their region number superimposed on a world globe. If a disc plays in more than one region it will have more than one number on the globe. Japan, Europe, South Africa, and Middle East including Egypt 3: Southeast Asia and East Asia including Hong Kong 4: Australia, New Zealand, Pacific Islands, Central America, Mexico, South America, and the Caribbean 5: Eastern Europe Former Soviet UnionIndian subcontinent, Africa, North Korea, and Mongolia 6: Special international venues airplanes, cruise ships, etc.

Technically there is no such thing as a region zero disc or a region zero player. There is such thing as an all-region disc. There are also all-region players. Some players can be "hacked" using special command sequences from the remote control to switch regions or play all regions. Some players can be physically modified "chipped" to play discs regardless of the regional codes on the disc. This usually voids the warranty, but is not illegal in most countries since the only thing that requires player manufacturers to region-code their players is the CSS license; see 1.

Many retailers, especially outside North America, sell players that have already been modified for multiple regions, or in some cases they simply provide instructions on how to access the "secret" region change features already built into the player. As an interesting side note, on Feb. Extensive information about modifying players and buying region-free players can be found on the Internet see 6. In addition to region codes, there are also differences in discs for NTSC and PAL TV systems see 1.

There's Something About Mary and Psycho are examples. In lateWarner Bros. They called it "region code enhancement" RCE, also known as REAand it received much publicity. RCE was first added to discs such as The Patriot and Charlie's Angels. They may not work on auto-switching players that recognize and match the disc region. It depends on the default region setting of the player. An RCE disc has all its region flags set so that the player doesn't know which one to switch to.

The disc queries the player for the region setting and aborts playback if it's the wrong one. A default player setting of region 1 will fool RCE discs from region 1. Playing a region 1 disc for a few seconds sets most auto-switching players to region 1 and thus enables them to play an RCE disc. When an RCE disc detects the wrong region or an all-region player, it will usually put up a message saying that the player may have been altered and that the disc is not compatible with the player.

A serious side effect is that some legitimate players fail the test, such as the Fisher DVDS There was much wailing and gnashing of teeth when RCE first appeared, but DVD fans quickly learned that it only affected some players.

Makers of player modification kits that didn't work with RCE soon improved their chips to get around it.

Mac - Apple

For every higher wall there is a taller ladder. See DVDTalk's RCE FAQ for more info and workarounds. In general, region codes don't apply to recordable DVDs. A DVD that you make on a PC with a DVD burner or in a home DVD video recorder will play in all regions but don't forget NTSC vs. PAL differences, see 1. Region codes do not apply to DVD-Audio. Regional codes apply to game consoles such as PlayStation 2 and Xbox, but only for DVD-Video movie discs see DVDRegionX for region modifications to PS2.

PlayStation has a separate regional lockout scheme for games. Regional codes also apply to DVD-ROM computers, but affect only DVD-Video discs, not DVD-ROM discs containing computer software.

Computer playback systems check for regional codes before playing movies from a CSS-protected DVD-Video see 1. Newer RPC2 DVD-ROM drives let you change the region code several times. RPC stands for region protection control. Once an RPC2 drive has reached the limit of 5 changes it can't be changed again unless the vendor or manufacturer resets the drive.

The Drive Info utility can tell you if you have an RPC2 drive it will say "This drive has region protection". Since December 31,only RPC2 drives have been manufactured. CPSA content protection system architecture is the name given to the overall framework for security and access control across the entire DVD family. Developed by the " 4C " entity Intel, IBM, Matsushita, and Toshiba in cooperation with the Copy Protection Technical Working Group CPTWGit covers encryption, watermarking, protection of analog and digital outputs, and so on.

There are many forms of content protection that apply to DVD. The general term for a system that prevents taping is APS Analog Protection Systemalso sometimes called copyguard. Macrovision changes the composite video and s-video output in two ways: Unfortunately, it can degrade the picture, especially with old or nonstandard equipment. Macrovision was not present on analog component video output of early players, but is now required on component output AGC only, since there is no burst in a component signal.

The discs themselves contain "trigger bits" telling the player whether or not to enable Macrovision AGC, with the optional addition of 2-line or 4-line Colorstripe. The triggers occur about twice a second, which allows fine control over what part of the video is protected. The producer of the disc decides what amount of copy protection to enable and then pays Macrovision royalties accordingly several cents per disc.

Just as with videotapes, some DVDs are Macrovision-protected and some aren't. Inexpensive devices can defeat Macrovision, although only a few work against the more recent Colorstripe feature.

These devices go under names such as DVD Red, Video Clarifier, Image Stabilizer, Color Corrector, DVD Redand CopyMaster. Or you can build your own. Some DVD players can be modified to turn off Macrovision output see 6. Professional time-base correctors TBCs that regenerate line 21 also remove Macrovision.

APS affects only video, not audio. This is a serial copy generation management system SCMS designed to prevent initial copies or generational copies copies of copies. The CGMS information is embedded in the outgoing video signal. For CGMS to work, the equipment making the copy must recognize and respect the CGMS information. The analog standard CGMS-A encodes the data on NTSC line 21 in the XDS service or line CGMS-A is recognized by most digital camcorders and by some computer video capture cards they will flash a message such as "recording inhibited".

Professional time-base correctors TBCs that regenerate lines 20 and 21 will remove CGMS-A information from an analog signal. See subsections 6 and 7 below. Content Scramble System CSS is a data encryption and authentication scheme intended to prevent copying video files directly from DVD-Video discs. CSS was developed primarily by Matsushita and Toshiba. Each CSS player licensee is given a key from a master set of keys stored on every CSS-encrypted disc. The theory was to allow a license to be revoked by removing its key from future discs.

The CSS decryption algorithm exchanges keys with the drive unit to generate an encryption key that is then used to obfuscate the exchange of disc keys and title keys that are needed to decrypt data from the disc. DVD players have CSS circuitry that decrypts the data before it's decoded and displayed, and computer DVD decoder hardware and software must include a CSS decryption module. All DVD-ROM drives have extra firmware to exchange authentication and decryption keys with the CSS module in the computer.

As of DVD-ROM drives are required to support regional management in conjunction with CSS see 1. Makers of equipment used to display DVD-Video drives, decoder chips, decoder software, display adapters, etc. CSS is administered by the DVD Copy Control Association DVD CCA. Near the end of MayCSS licenses were finally granted for software decoding. The license is extremely restrictive in an attempt to keep the CSS algorithm and keys secret.

Of course, nothing that's used on millions of players and drives worldwide could be kept secret for long. In Octoberthe CSS algorithm was cracked and posted on the Internet, triggering endless controversies and legal battles see 4.

It was developed as an improvement on CSS. Keys are stored in the lead-in area, but unlike CSS no title keys are placed in the sector headers. Each volume has a bit album identifier, similar to a CSS disc key, stored in the control area. Each disc contains a media key block, stored in a file in the clear on the disc.

The media key block data is logically ordered in rows and columns that are used during the authentication process to generate a decryption key from a specific set of player keys device keys. As with CSS, the media key block can be updated to revoke the use of compromised player keys. If the device key is revoked, the media key block processing step will result in an invalid key value.

The authentication mechanism is the same as for CSS, so no changes are required to existing drives. It is supported by some DVD recorders, but not by many DVD players. Each blank recordable DVD has a unique bit media ID etched in the BCA see 3.

When protected content is recorded onto the disc, it can be encrypted with a bit C2 Cryptomeria cipher derived from the media ID. During playback, the ID is read from the BCA and used to generate a key to decrypt the contents of the disc. If the contents of the disc are copied to other media, the ID will be absent or wrong and the data will not be decryptable. The draft proposal called 5C, for the five companies that developed it was made by Intel, Sony, Hitachi, Matsushita, and Toshiba in February Sony released a DTCP chip in mid Under DTCP, devices that are digitally connected, such as a DVD player and a digital TV or a digital VCR, exchange keys and authentication certificates to establish a secure channel.

This keeps other connected but unauthenticated devices from stealing the signal. No encryption is needed for content that is not copy protected. Security can be "renewed" by new content such as new discs or new broadcasts and new devices that carry updated keys and revocation lists to identify unauthorized or compromised devices. A competing proposal, XCA extended conditional accessfrom Zenith and Thomson, is similar to DTCP but can work with one-way digital interfaces such as the EIA RF remodulator standard and uses smart cards for renewable security.

Other proposals have been made by MRJ Technology, NDS, and Philips. In all five proposals, content is marked with CGMS-style flags of "copy freely", "copy once," "don't copy," and sometimes "no more copies". Digital devices that do nothing more than reproduce audio and video will be able to receive all data as long as they can authenticate that they are playback-only devices.

Digital recording devices are only able to receive data that is marked as copyable, and they must change the flag to "don't copy" or "no more copies" if the source is marked "copy once. They require new DVD players with digital connectors such as those on DV equipment. These new products began to appear in Since the encryption is done by the player, no changes are needed to existing discs.

Inthe Digital Display Working Group DDWG was formed to create a universal interface standard between computers and displays to replace the analog VGA connection standard. The resulting Digital Visual Interface DVI specification, released in Aprilwas based on Silicon Image's PanelLink technology, which at 4.

Intel proposed HDCP as a security component for DVI. A new connection standard called HDMI combines DVI and HDCP. DVD players with DVI or HDMI digital video output appeared in spring Many new HDTV displays are likely to have both IEEE and HDMI connections. HDCP provides authentication, encryption, and revocation. Specialized circuitry in the playback device and in the display monitor encrypts video data before it is sent over the link.

When an HDMI output senses that the connected monitor does not support HDCP, it lowers the image quality of protected content. The HDCP key exchange process verifies that a receiving device is authorized to display or record video. It uses an array of forty bit secret device keys and a bit key selection vector -- all supplied by the HDCP licensing entity. If the security of a display device is compromised, its key selection vector is placed on the revocation list.

The host device has the responsibility of maintaining the revocation list, which is updated by system renewability messages SRMs carried by newer devices and by video content.

Once the authority of the receiving device has been established, the video is encrypted by an exclusive-or operation with a stream cipher generated from keys exchanged during the authentication process. If a display device with no decryption ability attempts to display encrypted content, it appears as random noise.

The first four forms of copy protection Macrovision, CGMS, CSS, and CPPM are optional for the producer of a disc. CSS decryption is optional for hardware and software playback manufacturers, although a player or computer without decryption capability will only be able to play unencrypted movies. CPRM is handled automatically by DVD recorders, although it's optional and many recorders don't support it. DTCP and HDCP are handled by DVD players with digital video outputs.

These copy protection schemes are designed only to guard against casual copying which the studios claim causes billions of dollars in lost revenue. The goal is to "keep the honest people honest.

Movie studios have promoted legislation making it illegal to defeat DVD copy protection. The result is the World Intellectual Property Organization WIPO Copyright Treaty and the WIPO Performances and Phonograms Treaty December and the compliant U.

Digital Millennium Copyright Act DMCApassed into law in October Software intended specifically to circumvent copy protection is now illegal in the U. A co-chair of the legal group of the DVD copy protection committee stated, "in the video context, the contemplated legislation should also provide some specific assurances that certain reasonable and customary home recording practices will be permitted, in addition to providing penalties for circumvention.

DVD-ROM drives and computers, including DVD-ROM upgrade kits, are required to support Macrovision, CGMS, and CSS. PC video cards with TV outputs that don't support Macrovision will not work with encrypted movies. Likewise computers with HDMI DVI connections must support HDCP to output DVD-Video content. Every DVD-ROM drive must include CSS circuitry to establish a secure connection to the decoder hardware or software in the computer, although CSS can only be used on DVD-Video content.

Of course, since a DVD-ROM can hold any form of computer data, other encryption schemes can be implemented. The Watermarking Review Panel WaRP --the successor to the Data-Hiding Sub-Group DHSG -- of the CPTWG selected an audio watermarking system that has been accepted by the DVD Forum for DVD-Audio see 1. The original seven video watermarking proposals were merged into three: On February 17,the first two groups combined to form the "Galaxy Group" and merged their technologies into a single proposal.

The second group has dubbed their technology "Millennium. Watermark signatures can be recognized by playback and recording equipment to prevent copying, even when the signal is transmitted via digital or analog connections or is subjected to video processing.

Watermarking is not an encryption system, but rather a way to identify whether a copy of a piece of video or audio is allowed to be played. New players and software are required to support watermarking, but the DVD Forum intends to make watermarked discs compatible with existing players. Reports were made that the early watermarking technique used by Divx caused visible "raindrop" or "gunshot" patterns, but the problem was apparently solved for later releases.

When DVD was released in there was no DVD-Audio format, although the audio capabilities of DVD-Video far surpassed CD. The DVD Forum sought additional input from the music industry before defining the DVD-Audio format. A draft standard was released by the DVD Forum's Working Group 4 WG4 in Januaryand version 0.

The final DVD-Audio 1. The scheduled October release was further delayed until midostensibly because of concerns caused by the CSS crack see 4. Pioneer released the first DVD-Audio players without copy protection support in Japan in late Pioneer, JVC, Yamaha, and others released DVD-Audio players in fall and early By the end of there were about 50 DVD-Audio titles available.

By the end of there were just under DVD-Audio titles available. DVD-Audio is a separate format from DVD-Video. New DVD-Audio players are needed, or new "universal players" that can play both DVD-Video and DVD-Audio discs.

Universal players are also called VCAPs video-capable audio players. A plea to producers: Universal players are rare, but you can make universal discs easily. With a small amount of effort, all DVD-Audio discs can be made to work on all DVD players by including a Dolby Digital version of the audio in the DVD-Video zone.

A plea to DVD-Audio authoring system developers: Make your software do this by default or strongly recommend this option during authoring. DVD-Audio players and universal players work with existing receivers.

They output PCM and Dolby Digital, and some will support the optional DTS and DSD formats. However, most current receivers can't decode high-definition, multichannel PCM audio see 3.

DVD-Audio players with high-end digital-to-analog converters DACs can only be hooked up to receivers with 2-channel or 6-channel analog inputs, but some quality is lost if the receiver converts back to digital for processing. New receivers with improved digital connections such as IEEE FireWire are needed to use the full digital resolution of DVD-Audio.

DVD audio is copyright protected by an embedded signaling or digital watermark feature. This uses signal processing technology to apply a digital signature and optional encryption keys to the audio in the form of supposedly inaudible noise so that new equipment will recognize copied audio and refuse to play it. Proposals from Aris, Blue Spike, Cognicity, IBM, and Solana were evaluated by 10 minute binary options system karaoke strategy music companies in conjunction with insider trading and forex 4C Entity, comprising IBM, Intel, Matsushita, and Toshiba.

Aris and Solana merged to form a new company called Verance, whose Galaxy technology was chosen for DVD-Audio in August In NovemberVerance watermarking was also selected for SDMI. Verance and 4C claimed that tests on the Verance watermarking method showed it was inaudible, but golden-eared listeners in later tests were able to detect the watermarking noise.

Sony and Philips have developed a competing Super Audio CD format that uses DVD discs. Sony released version 0. Most initial SACD releases have been mixed in stereo, not multichannel. SACD was originally supposed to provide "legacy" discs with two layers, one that plays in existing CD players, plus a high-density layer for DVD-Audio players, but technical difficulties kept dual-format discs from being produced until the end ofand only then in small quantities.

Pioneer, which released the first DVD-Audio players in Japan at the end ofincluded SACD support in their DVD-Audio players. If other manufacturers follow suit, the entire SACD vs. DVD-Audio standards debate could be moot, since DVD-Audio players would play both types of discs. The player was released in limited quantities in the U. About 40 SACD titles were available at the end offrom studios such as DMP, 10 minute binary options system karaoke strategy Fidelity Labs, Pioneer, Sony, and Telarc.

Over SACD titles were available by the end of A drawback related to DVD-Audio and SACD players is that most audio receivers with 6 channels of analog input aren't able to do bass management. Receivers with Dolby Digital and DTS decoders handle bass management internally, but 6-channel analog inputs are usually passed straight through to the amplifier. Without full bass management on 6-channel analog inputs, any audio setup that doesn't have full-range speakers for all 5 surround channels will not properly reproduce all the bass frequencies.

If you are interested in making the most of a DVD-Audio or SACD player, you need a receiver with 6-channel analog audio inputs. You also need 5 full-frequency speakers that is, each speaker should be able to handle subwoofer frequencies and a subwoofer, unless you have a receiver that can perform bass management on the analog inputs, or you have an outboard bass management box such as from Outlaw Audio.

For more on DVD-Audio, including lists of titles and player models, visit Digital Audio Guide. DVD-Music isn't actually an official DVD format, but it has become a 1 usd to rub forex used name for a DVD-Video disc that contains primarily music.

A DVD-Music disc plays in any standard DVD player with video or still pictures that accompany the audio. As explained in 1. When DVD players became available in earlyWarner and Polygram were the only major movie studios to release titles. Additional titles were available from small publishers.

The other studios gradually joined the DVD camp see 6. Dreamworks was the last significant studio to announce full DVD support.

Paramount, Fox, and Dreamworks initially supported only Divx, but in summer they each announced support for open DVD. Yes, if you have a DVD recorder. When DVD was originally introduced inonly players were available. Most DVD units sold today are still play-only, but recorders are available and affordable. DVD video recorders first appeared in Japan at the end book typing work at home in delhiand in the rest of the world at the end of DVD recorders are being added to satellite and cable receivers, hard-disk video recorders, and other advanced consumer electronics devices.

An important difference is that you never have to rewind or fast forward -- recordings on a disc are instantly accessible, usually from an on-screen menu.

Many DVD recorders include an electronic program guide EPG that gives you onscreen TV listings from which you can pick shows to record no need to enter day, time, channel, and so on by hand. Although DVD recorders use digital recording, most inputs are analog video that is digitized inside the recorder. As of there are no DVD recorders with digital tuners, so they are unable to directly record digital broadcasts such as U. DTV or European DVB.

Note that Westfield hornsby opening hours australia day video recorders can't copy most DVD movie discs, which are protected see 1.

Unfortunately there is more than one recordable DVD format, and they don't survey review earn money india without investment play together nicely. It's nothing like the old "VHS vs. Betamax battle" as many in the press would have you believe, but it is rather confusing.

Don't be further confused by DVD recordable drives DVD burners for computers see 4. These recorders can store data, but to create full-featured DVD-Videos requires additional software to do video encoding MPEGaudio encoding Dolby Digital, MPEG, or PCMnavigation and control data generation, and so on see 5. Scratches may cause minor data errors that are easily corrected. That is, data is stored on DVDs using powerful error correction techniques that can recover from even large scratches with no loss of data.

A common misperception is that a scratch will be worse on a DVD than on a CD because of higher storage density and because video is heavily compressed.

DVD data density say that fast ten times! But DVD error correction is at least ten times better than CD-ROM error correction and more than makes up for the density increase. It's also important to realize that MPEG-2 and Dolby Digital compression are partly based on removal or reduction of imperceptible information, so decompression doesn't expand the data as much as might be assumed.

Paradoxically, sometimes the smallest scratches can cause the worst errors because of the particular orientation and refraction of the scratch. There are many schemes for concealing errors in MPEG video, which may be used in future players. The DVD computer advisory group specifically requested no mandatory caddies or other protective carriers.

Consider that laserdiscs, music CDs, and CD-ROMs are likewise subject to scratches, but many video stores and libraries rent them. Major chains such as Blockbuster and West Coast Entertainment rent DVDs in many locations. Most reports of rental disc performance are positive, although if you have problems playing a rental disc, check for scratches.

The primary advantages of DVD are video quality, surround sound, and extra features see 1. In addition, DVD will not degrade with age or after many playings like videotape will which is an advantage for parents with kids who watch Disney videos twice a week!

This is the same thing that makes CDs more collectable than cassette tapes. Did I mention video quality? The better your TV, the bigger the difference in picture quality between VHS and DVD. Manufacturers were worried about customers assuming DVDs would play in their CD player, so they wanted the packaging to be different. However, no one is being forced to use a larger package size.

Some companies use standard jewel cases or paper and vinyl sleeves. Divx discs came in paperboard and plastic Q-Pack cases the same size as a CD jewel case.

Most movies are packaged in the Amaray "keep case," an all-plastic clamshell with clear vinyl pockets for forex exchange rates in india, that's popular among consumers.

Time Warner's "snapper," a paperboard case with a plastic lip, is less popular. There's also a "super jewel box," the stretch-limo version of a CD jewel case, that's common in Europe.

A dual-layer disc has two layers of data, one of them semi-transparent so that the laser can focus through it and read the second layer. Since both layers are read from the same side, a dual-layer disc can hold almost twice as much as a single-layer disc, typically 4 hours of video see 3.

Many discs use dual layers. Initially only a few replication stock options for ivn could make dual-layer discs, but most plants now have the capability. The second layer can use either a PTP parallel track path layout where both tracks run in parallel for independent data or special switching effects valuing call option on bond, or an OTP opposite track path layout where the second track runs in an opposite spiral; that is, the pickup head reads out from the center on the first track then in from the outside on the second track.

The OTP layout, also called RSDL reverse-spiral dual layer how to make money in dead frontier online, is designed to provide continuous video across both layers.

When the laser pickup head reaches the end of the first layer it changes focus to the second layer and starts moving back toward the center of the disc. The layer change can occur anywhere in the video; it doesn't have to be at a chapter point. There's no guarantee that the switch between layers will be seamless. The layer change is invisible on some players, but it can cause the video to freeze for a fraction of a second or as long as 4 seconds on other players.

The "seamlessness" depends as much on the way the disc is prepared as on the design of the player. The advantage of two layers is that long movies can use higher data rates for better quality than with a single layer.

There are various ways to recognize dual-layer discs: The DVD specification requires that players and drives read dual-layer discs. There are very few units that have problems with dual-layer discs--this is a design flaw and should be corrected for free by the manufacturer. Some discs are designed with a "seamless layer change" that technically goes beyond what the DVD spec allows.

This causes problems on a few older players. All players and drives also play double-sided discs if you flip them over. No manufacturer has announced a model that will play both sides, other than a few DVD jukeboxes. The added cost would be hard to justify since discs can hold over 4 hours of video on one side by using two layers. Early discs used two sides because dual-layer production was not widely supported.

This is no longer a problem. Video on a DVD is stored in digital format, but it's formatted commodity options vs stock options one of two mutually incompatible television systems: Therefore, there are two kinds of DVDs: Discs are also coded for different regions of the world see 1. NTSC is the TV format used in Canada, Fut 13 money cheats xbox 360, Mexico, Philippines, Taiwan, United States, and other countries.

PAL is the TV format used in most of Europe, most of Africa, China, India, Australia, New Zealand, Israel, North Korea, and other countries. See the chart at www. Almost all DVD players sold in PAL countries play both kinds of discs. These multi-standard players partially convert NTSC to a Hz PAL 4. The player uses the PAL 4. Most modern PAL TVs can handle this "pseudo-PAL" signal. A few multi-standard PAL players output true 3.

Some players have a switch to choose Hz PAL or true NTSC output when playing NTSC discs. There are a few standards-converting PAL players that convert from an NTSC disc to standard PAL output for older PAL TVs.

Proper "on the fly" standards conversion requires expensive hardware to handle scaling, temporal conversion, and object motion analysis. Because the quality of conversion in DVD players is poor, using Hz PAL output with a compatible TV provides a better picture than converting from NTSC to PAL. Sound is not affected by video conversion. Most NTSC players can't play PAL discs, and most Over the counter or exchange traded derivatives TVs don't work with PAL video.

A very small number of NTSC players such as Apex and SMC can convert PAL to NTSC. High-quality converters are available from companies such as TenLab and Snell and Wilcox. Beware, some standards-converting players can't convert anamorphic widescreen video for 4: The latest software tools such as Adobe After Effects and Canopus ProCoder do quite a good job of converting between PAL and NTSC at low cost, but they are only appropriate for the production environment converting the video before it is encoded and put on the DVD.

See Snell and Wilcox's The Engineer's Guide to Standards Conversion and The Engineer's Guide to Motion Compensation for technical details of conversion.

There are three differences between discs intended for playback on different TV systems: All PAL DVD players can play Dolby Digital audio tracks, but not all NTSC players can play MPEG audio tracks.

PAL and SECAM share the same scanning format, so discs are the same for both systems. The only difference is that SECAM players output the color signal in the format required by SECAM TVs. Note that modern TVs in most SECAM countries can also read PAL signals, so you can use a player that only has PAL output.

The only case in which you need a player with SECAM output is for older SECAM-only TVs and you'll probably need a SECAM RF connection, see 3. Most studios put Dolby Digital audio tracks on their PAL discs instead of MPEG audio tracks. Because of PAL's higher resolution, the video usually takes more space on the disc than the NTSC version. There are actually three types of DVD players if you count computers. Most DVD PC software and hardware can play both NTSC and PAL video and both Dolby Digital and MPEG audio.

Some PCs can only display the converted video on the computer monitor, but others can output it as a video signal for a TV. PAL discs play on very few players outside of PAL countries. This is irrespective of regions -- see 1. Some people claim that animation, especially hand-drawn cell animation such as cartoons and anime, does not compress well with MPEG-2 or even ends up larger than the original.

Other people claim that animation is simple so it compresses better. Supposedly the "jitter" between frames caused by differences in the drawings or in their alignment causes problems. An animation expert at Disney pointed out that this doesn't happen with modern animation techniques. And even if it did, the motion estimation feature of MPEG-2 would compensate for it. Because of the way MPEG-2 breaks a picture into blocks and transforms them into frequency information it can have a problem with the sharp edges common in animation.

This loss of high-frequency information can show up as "ringing" or blurry spots along edges called the Gibbs effect. However, at the data rates commonly used for DVD this problem does not usually occur.

Even though DVD's dual-layer technology see 3. Most "flipper" discs exist because of producers who are too lazy to optimize the compression or make a dual-layer disc. Better picture quality is a cheap excuse for increasing the data rate; in many cases the video will look better if carefully encoded at a lower bit rate. Lack of dual-layer production capability is also a lame excuse; in very few DVD plants could make dual-layer discs, but this is no longer the case.

Very few players can automatically switch sides, but it's not needed since most movies less than 4 hours long can easily fit on one dual-layer RSDL side. The Film Vault at DVD Review includes a list of "flipper" discs. You are watching an anamorphic picture intended for display only on a widescreen TV. You need to go into the player's setup menu and tell it you have a standard 4: It will then automatically letterbox the picture so you can see the full width at the proper proportions.

In some cases you can change the aspect ratio as the disc is playing by pressing the "aspect" button on the remote control. On most players you have to stop the disc before you can change aspect. Some discs are labeled with widescreen on one side and standard on the other. In order to watch the fullscreen version you must flip the disc over. Apparently most players that convert from NTSC to PAL or vice-versa see 1. Solutions are to use a widescreen TV, a multistandard TV, or an external converter.

Or get a better player. Most DVD-Video discs contain Dolby Digital soundtracks. However, it's not required. Some discs, especially those containing only audio, have PCM tracks. Discs with DTS audio are required to also include a Dolby Digital audio track in a few rare cases they have a PCM track.

Don't assume that the Dolby Digital label is a guarantee of 5. A Dolby Digital soundtrack can be mono, dual mono, stereo, Dolby Surround stereo, etc.

For example, Blazing Saddles and Caddyshack have monophonic soundtracks, so what are partners in binary options trading Dolby Digital soundtrack on these DVDs has only one channel.

Some DVD packaging has small lettering or icons under the Dolby Digital logo that indicates the channel configuration. In some cases, there is more than one Dolby Digital version of a soundtrack: It's perfectly normal for your DVD player to indicate playback of a Dolby Forex directory net zar audio track while your receiver indicates Dolby Surround.

This means the disc contains a two-channel Tassazione stock option estere 2016 Surround signal encoded in Dolby Digital format. Laser rot is a colloquial term referring to various defects or deteriorations of optical discs. There are rare cases of problems with DVDs, but these have largely disappeared as manufacturing processes have improved.

The result of deterioration is that a disc which played perfectly when it was new develops problems later, such as skipping, freezing, or picture breakup.

If a disc seems to go bad, make sure it's not dirty, scratched, or warped see 1. Try cleaning it and try playing it in other players. If the disc consistently has problems, it may have deteriorated. If so, there's nothing you can do to fix it, so you should try to get a replacement from the supplier. Before DVDs there were laserdiscs see 2. This usually results from the use of insufficiently pure metal for the reflective coating created during replication, but can be exacerbated by mechanical shear stress due to bending, warping or thermal cycles the large size of laserdiscs makes them flexible, so that movement along the bond between layers can break the seal -- this is called delamination.

Deterioration of the data layer can be caused by chemical contaminants or gases in the glue, or by moisture that penetrates the plastic substrate. Like laserdiscs, DVDs are made of two platters glued together, but DVDs are more rigid and use newer adhesives.

DVDs are molded from polycarbonate, which absorbs about ten times less moisture than the slightly hygroscopic acrylic PMMA used for laserdiscs. DVDs can have delamination problems, partly because some cases or players hold too tightly to the hub. Delamination by itself can cause problems because the data layer is no longer at the correct distance from the surface and can also lead to oxidation. Delamination may appear as concentric rings or a "stain" around the hub.

DVDs have few "DVD rot" problems. Around there were reports of a few discs going bad, possibly due to delamination, contaminated adhesive, chemical reactions, or oxidation of the reflective layer see Yerington and Byrnes. The most likely explanation for DVD deterioration is that during the early days of DVDdisc manufacturing processes and materials were not as good as they should have been. Many improvements have been made since then, so the minuscule problem seems to have become even more minuscule.

There are occasional reports of "cloudiness" or "milkiness" in DVDs, which can be caused by improper replication. Minimal clouding doesn't hurt playback and doesn't seem to deteriorate. If you can see something with your naked eye it is probably not oxidation or other deterioration.

In some cases the original film or rights to it are no longer available for a new transfer. In the case of old movies, they were shot full frame in the 1. Video shot with TV cameras, such as music concerts, is already in 4: Some movies, especially those over two hours long or encoded at a high data rate, are spread across two layers on one side of the disc.

When the player changes to the second layer, the video and audio may freeze for a moment as the laser refocuses and finds its place. The length of the pause depends on the player and on the layout of the disc. The disc producer usually tries to choose a point where the pause will be less noticeable.

The pause is not a defect in the player or the disc. There is a list of layer switch points in the Film Vault at DVD Review. Please send new times to info dvdreview. Some discs many from Columbia TriStar have 2-channel Dolby Surround audio or plain stereo on track one and 5. Some studios create separate sound mixes optimized for Dolby Surround or stereo, and they feel the default track should match the majority of sound systems in use.

Unless you specifically select the 5. Some players have a feature to automatically select the first 5. Dolby Digital doesn't necessarily mean 5. Almost all features of DVD such as search, pause, and scan can be disabled by the disc, which can prevent the player from searching back to the beginning of a segment.

If the player how much does a cvs pharmacy cashier make time search to repeat a segment, then a disc with fancy non-sequential title organization will not have timecode information the player needs to search.

In many cases the authors don't even realize they have prevented the use of the repeat feature. There is no meaningful answer to this question, since you'll get a different response from everyone you ask.

The terms "2nd generation" and "3rd generation," and so on refer both to DVD-Video players and to DVD-ROM forexsystems.ru graal. In general, they simply mean newer versions of DVD playback devices.

The terms haven't been used yet to refer to DVD products that can record, play video games, or so on. According to some people, second-generation DVD players came out in the fall of and third-generation players are those that came out in the beginning of According to others, the second generation of DVD will be HD players see 2. Many conflicting variations occur between these extremes, including the viewpoint that DTS-compatible players or Divx players or progressive-scan players or bit video players or players that can play The Matrix constitute the second, third, or fourth generation.

Things are risk reversal stock options little more clear cut on the PC side, where second generation DVD II usually means 2x DVD-ROM drives that can read CD-Rs, and third generation DVD III usually means 5x or sometimes 2x or 4.

Some people refer to RPC2 drives or 10x drives as fourth generation. Digital Theater Systems Digital Surround is an audio encoding format similar to Dolby Digital.

It requires a decoder, either in the player or in an external receiver. Some people claim that, because of its lower compression level, DTS sounds better than Dolby Digital. Because of the many variances in production, mixing, decoding, and reference levels, it's almost impossible to accurately compare the two formats DTS usually produces a higher volume level, causing it to sound better in casual comparisons. DTS originally did all encoding in house, but as of October DTS encoders became available for purchase.

DTS titles are often considered to be specialty items intended for audio enthusiasts, so some DTS titles are also available in a Dolby Digital-only version. DTS is an optional format on DVD. Contrary to uninformed claims, the DVD specification has included an ID code for DTS since before the spec was even finalized. Because DTS was slow in releasing encoders and test discs, players made before mid and many since ignore DTS tracks. A few demo discs were created in by embedding DTS data into a PCM track the same technique used with CDs and laserdiscsand these are the only DTS Forex trgovanje u srbiji discs that work on all players.

New DTS-compatible players arrived in midbut theatrical DTS discs using the DTS audio stream ID did not appear until January 7, they were originally scheduled to arrive in time for Christmas Mulan, a direct-to-video animation not the Disney movie with DTS soundtrack appeared in November DTS-compatible players carry an official "DTS Digital Out" logo.

This means that all DTS discs will work in all DVD players, but a DTS-compatible player and a DTS decoder are required to play the DTS soundtrack.

DTS audio CDs work on all DVD players, because the DTS data is encapsulated into standard PCM tracks that are passed untouched to the digital audio output. DTS discs often carry a Dolby Digital 2.

You may have connected one of the component outputs usually colored red, green, and blue of your DVD player to the composite input of your TV. Connect yellow to yellow.

Also, if you've hooked up component forex platforms broker reviews blogs, check the three cables to make sure one of them hasn't become disconnected or developed a short and that they are connected in the correct order. If you use an s-video connection, the chroma wire maybe broken -- try a different cable or try the composite connection.

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If you live in overnight trading in grain futures pdf PAL country most countries outside of the U. If easy forex made trading player has a switch or on-screen setting to select the output format for NTSC discs, choosing PAL 60 Hz should solve the problem.

Many DVD's are labeled as having widescreen If you think both sides how does warren jeffs make money the same, you're nifty option intraday chart seeing uncompressed It may look like 4: The problem is that your player has been set for a widescreen TV.

There have been numerous reports of "lip sync" problems, where the audio lags slightly behind the video or sometimes precedes the video. Perception of a sync problem is highly subjective; some people are bothered by it while others can't discern hedging against foreign exchange risk. Problems have been reported on a variety of players notably the Pioneer and models, possibly all Pioneer models, some Sony models including the series and the PS2, some Toshiba models including theand some PC decoder cards.

Certain discs are also more problematic notably Lock, Stock, and Two Smoking Barrels; Lost In Space; TRON; The Parent Trap; and Austin Powers. Factor 1 or 2 usually must be present in order for factor 3 or 4 to become apparent. Some discs with severe sync problems have been reissued after being re-encoded to fix the problem.

In some cases, the sync problem in players can be fixed by pausing or stopping playback and then restarting, or by turning the player off, waiting a few seconds, then turning it back on. A good way to test your player is to simultaneously listen to the analog and digital outputs play the digital output through your stereo and the analog output through forex ea lab by mark larsen TV.

If the audio echoes or sounds hollow, then the player is delaying the signal and is thus the main cause of the sync problem. Unfortunately, there is no simple answer and no simple fix. More complaints from customers should motivate manufacturers to take the problem more seriously and correct it in future players or with firmware honda stock market data api. Pioneer originally stated that altering the audio-visual synchronization of their players "to compensate for the software quality would dramatically compromise the picture performance.

If you have an older model, check with Pioneer about an upgrade. For many more details, see Michael D's Pioneer Audio Sync page. You are seeing the effects of Macrovision copy protection see 1.

Some DVD movies contain hidden features, often called Easter eggs. These are extra screens or video clips hidden in the disc by the developers.

For example, Dark City includes scenes from Lost in Space and the Twin Peaks movie buried in the biography pages of William Hurt and Keifer Sutherland. There's also an amusing "Shell Beach" game entwined throughout the menus. On Mallrats, perhaps indicating that DVD has already become too postmodern for its own good, there's a hidden clip of the director telling you to stop looking for Easter eggs and do something useful.

It's more fun to search for hidden features on your own, but if you need some help, the best list is at DVD Review. The black bars are part of the letterbox process see 3. If you how to make money in asheville nc the player to In some cases, there may be both a fullscreen and a letterbox version of the movie on the same disc, with a variety of ways to get to the fullscreen version usually only one works, so you may have to try all three:.

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DVD was designed to make movies look as good as possible on TV. Since most movies are wider than standard TVs, letterboxing preserves the format of the theatrical presentation.

Nobody seems to complain that the top and bottom of work from home reservationist jobs picture are cut off in theaters. DVD is ready for TVs how to make profit in runescape f2p the future, which are widescreen.

For these and other reasons, many movies on DVD are only available in widescreen format. About two thirds of widescreen movies are filmed at 1. In other words, the picture is the same sizewith extra areas visible at the top and bottom in the fullscreen version.

In more other words, letterboxing covers over the part of the picture that was also covered in the theater, or it allows the entire widescreen picture to be visible for movies wider than 1. If you have a widescreen TV, make sure your player is set to Most widescreen movies will fill the screen, but some movies are filmed at an aspect ratio of around 2.

These movies are usually letterboxed to fit the 1. Just be happy they're much thinner than they would be on a standard TV. If there's not a fullscreen version of the movie on the disc, one solution is to use a Boss binary options best payout player with a zoom feature to enlarge the picture enough to fill the screen.

This will cut off the sides of the picture, but in many cases it's a similar effect to the pan and scan process. Just think of it as "do-it-yourself pan and scan. For an explanation of anamorphic widescreen and links to more information and examples on other Web sites, see 3. The best solution to this entire mess might be the FlikFX Digital Recomposition System"the greatest advance in entertainment in 57 years. Since DVDs are read by a laser, they are resistant to fingerprints, dust, smudges, and scratches see 1.

However, surface contaminants and scratches can cause data errors. On a video player, the effect of data errors ranges from minor video artifacts to frame skipping to complete unplayability. So it's a good idea to take care of your discs. In general treat them the same way as you would a CD. Your player can't be harmed by a scratched or dirty disc unless globs of nasty substances on it actually hit the lens.

Still, it's best to keep your discs clean, which will also keep the inside of your player clean. Don't attempt to play a cracked disc, as it could shatter and damage the player. It doesn't hurt to leave the disc in the player, even if it's paused and still spinning, but leaving it running unattended for days on end might not be a good idea. In general, there's no need to clean the lens on your player, since the air moved by the rotating disc keeps it clean.

However, if you use a lens cleaning disc in your CD player, you may want to do the same with your DVD player. It's advisable to use a cleaning disc specifically designed for DVD players, because there are minor differences in lens positioning between DVD and CD players. Periodic alignment of the pickup head is not necessary. Sometimes the laser can drift out of alignment, especially after rough handling of the player, but this is not a regular maintenance item.

Handle only at the hub or outer edge. Don't touch the shiny surface with your popcorn-greasy fingers. Store in a protective case when not in use. Don't bend the disc when taking it out of the case, and be careful not to scratch the disc when placing it in the case or in the player tray. Keep discs away from radiators, heaters, hot equipment surfaces, direct sunlight near a window or in a car during hot weatherpets, small children, and other destructive forces.

Artificial light and indirect sunlight have no effect on replicated DVDs since they are made of polycarbonate, polymer adhesives, and metal usually aluminum or goldnone of which are significantly affected by exposure to light.

Magnetic fields have no effect on DVDs, so it's ok to leave them sitting on your speakers. Coloring the outside edge of a DVD with a green marker or any other color makes no difference in video or audio quality.

A bit of dye that on average is more than 3 million times farther away is not going to affect anything. NIST has prepared a 1-page guide and a page guide to disc care. If you notice problems when playing a disc, you may be able to correct them with a simple cleaning. If you continue to have problems after cleaning the disc, you may need to attempt to repair one or more scratches.

Sometimes even hairline scratches can cause errors if they just happen to cover an entire error correction ECC block. Examine the disc to find scratches, keeping in mind that the laser reads from the bottom. There are essentially two methods of repairing scratches: There are many commercial products that do one or both of these, or you may wish to do it yourself with polishing compounds or toothpaste. The trick is to polish out the scratch without causing new ones.

A mess of small polishing scratches may cause more damage than a big scratch. As with cleaning, polish only in the radial direction.

Libraries, rental shops, and other venues that need to clean a lot of discs may wish to invest in a commercial polishing machine that can restore indian stock market expert advice disc to pristine condition after an amazing amount of abuse.

Keep in mind that the data layer on a DVD is only half as deep as on a CD, so a DVD can only be repolished about half as many times. A progressive-scan DVD player converts the interlaced i or i video from DVD into progressive p or p format for connection to a surplus overstock buyers display Progressive players work with all standard DVD titles, but look best with film source.

The result is a significant increase in perceived vertical resolution for a more detailed and film-like picture. Since computers use progressive-scan monitors, DVD PCs are by definition progressive-scan players, although quality varies quite a bit see 4.

There's enormous confusion about whether DVD cara memahami news forex is progressive or interlaced.

Here's the one true answer: Progressive-source video such as from film is usually encoded on DVD as interlaced field pairs that can be reinterleaved by a progressive player to recreate the original progressive video. You must use a progressive-scan display in order to get the full benefit of a pdw stock options player.

However, all progressive players also include interlaced outputs, so you can use one with a standard TV until make money complete autopilot upgrade to a progressive TV.

You may have to use a switch on the back of the player to set it to interlaced output. Many manufacturers have released progressive models since then at progressively cheaper prices pun intended. It's also possible to buy an external line multiplier to convert the output of a standard DVD player to progressive scanning.

Converting interlaced DVD video to progressive video involves much more than putting film frames back together. There are essentially three ways to convert from interlaced to progressive: If the original video is from a progressive source, such as film, the two fields can be recombined into a single frame. If the original video is from an interlaced source, simply combining two fields will cause motion artifacts the effect is reminiscent of a zipperso each line of a single field is repeated twice to form a frame.

Better line doublers use interpolation to produce new lines that are a combination of the lines above and below. The term line doubler is vague, since cheap line doublers only bob, while expensive line doublers those that contain digital signal processors can also weave. There are three common kinds of deinterlacing systems: This is usually best, where the deinterlacer is integrated with the MPEG-2 decoder so that it can read MPEG-2 flags and analyze the encoded video to determine when to bob and when to weave.

Most DVD computers use this method. The digital video from the MPEG-2 decoder is passed to a separate deinterlacing chip. The disadvantage is that MPEG-2 flags and motion vectors may no longer available to help the deinterlacer determine the original format and cadence. Analog video from the DVD player is passed to a separate deinterlacer line multiplier or to a display with a built-in deinterlacer. In this case, the video quality is slightly degraded from being converted to analog, back to digital, and often back again to analog.

However, for high-end projection systems, a separate line multiplier which scales the video and interpolates to a variety of scanning rates may achieve the best results. Some use MPEG decoders with integrated deinterlacing. Some, such as Toshiba's "Super Digital Progressive" players and Panasonic's progressive-scan player add 4: Add-on internal deinterlacers such as the Cinematrix and MSB Progressive Plus are available to convert existing players to progressive-scan output.

FaroudjaSilicon Image DVDOand Videon Omega line multipliers are examples of external deinterlacers. A progressive DVD player has to determine whether the video should be line-doubled bobbed or reinterleaved weaved. When reinterleaving film-source video, an NTSC DVD player also has to deal with the difference between film frame rate 24 Hz and TV frame rate 30 Hz. Since the pulldown trick can't be used to spread film frames across video fields, there are worse motion artifacts than with interleaved video.

However, the increase in resolvable detail more than makes up for it. Advanced progressive players such as the Princeton PVD and DVD computers can get around the problem by displaying at multiples of 24 Hz such as 72 Hz, 96 Hz, and so on. A progressive player also has to deal with problems such as video that doesn't have clean cadence as when it's edited after being converted to interlaced video, when bad fields are removed during encoding, when the video is speed-shifted to match the audio track, and so on.

Another problem is that many DVDs are encoded with incorrect MPEG-2 flags, so the reinterleaver has to recognize and deal with pathological cases. In some instances it's practically impossible to determine if a sequence is frame interlaced video or frame progressive video. For example, the documentary on Apollo 13 is interlaced video encoded as if it were progressive. Other examples of improper encoding are TitanicAustin PowersFargo, More Tales of the City, the Galaxy Quest theatrical trailer, and The Big Lebowski making-of featurette.

One problem is that many TVs with progressive input don't allow the aspect ratio to be changed -- they assume all progressive-scan input is anamorphic. When a non-anamorphic 4: Before you buy a DTV, make sure that it allows aspect ratio adjustment on progressive input. Or get a player with an aspect ratio control option that "windowboxes" 4: Because of the added scaling step this degrades picture quality, but at least it gets around the problem. Just as early DVD computers did a poor job of progressive-scan display of DVDs, the first generations of progressive consumer players are also a bit disappointing.

But as techniques improve, and as DVD producers become more aware of the steps they must take to ensure good progressive display, and as more progressive displays appear in homes, the experience will undoubtedly improve, bringing home theaters closer to real theaters.

For more on progressive video and DVD, see part 5 and player ratings in the excellent DVD Benchmark series at Secrets of Home Theater and High Fidelity. The DVD specification is complex and open to interpretation. DVD-Video title authoring is also very complex. As with any new technology, there are compatibility problems.

The DVD-Video standard has not changed substantially since it was finalized inbut many players don't properly support it.

Discs have become more complex as authoring tools improve, so recent discs often uncover engineering flaws in players. Some discs behave strangely or won't play at all in certain players. In some cases, manufacturers can fix the problem with an upgrade to the player see 1. In other cases, disc producers need to reauthor the title to correct an authoring problem or to work around a player defect. Problems can also occur because of damaged or defective discs or because of a defective player.

For other DVD and home theater problems, try Doc DVD or DVD Digest's Tech Support Zone. If you have a Samsungsee the Samsung FAQ. For troubleshooting DVD on computers, see 4. The Dell Inspiron DVD Movie List has Inspiron-specific problems. Below are problems reported by readers of this FAQ.

The FAQ author has not verified these claims and takes no responsibility for their accuracy. Please report other confirmed problems. DVD includes parental management features for blocking playback and for providing multiple versions of a movie on a single disc.

Players including software players on PCs can be set to a specific parental level using the onscreen settings. If a disc with a rating above that level is put in the player, it won't play.

In some cases, different programs on the disc have different ratings. The level setting can be protected with a password. A disc can also be designed so that it plays a different version of the movie depending on the parental level that has been set in the player. By taking advantage of the seamless branching feature of DVD, objectionable scenes are automatically skipped over or replaced during playback.

This requires that the disc be carefully authored with alternate scenes and branch points that don't cause interruptions or discontinuities in the soundtrack. There is no standard way to identify which discs have multi-rated content. Unfortunately, very few multi-rating discs have been produced. Hollywood studios are not convinced that there is a big enough demand to justify the extra work involved shooting extra footage, recording extra audio, editing new sequences, creating branch points, synchronizing the soundtrack across jumps, submitting new versions for MPAA rating, dealing with players that don't properly implement parental branching, having video store chains refuse to carry discs with unrated content, and much more.

If this feature is important to you, let the studios know. A list of studio addresses is available at DVD Fileand there's a Studio and Manufacturer Feedback area at Home Theater Forum. You might also want to visit the Viewer Freedom site. Multi-ratings discs include Kalifornia, Crash, Damage, Embrace of the Vampire, Poison Ivy, Species II. In most cases these discs provide "un-cut" or unrated versions that are more intense than the original theatrical release. Discs that use multi-story branching not always seamless for a director's cut or special edition version include Dark Star, Stargate SE, The Abyss, Independence Day, and Terminator 2 SE release.

Also see multipath movies at Brilliant Digital. Another option is to use a software player on a computer that can read a playlist telling it where to skip scenes or mute the audio. Playlists can be created for the thousands of DVD movies that have been produced without parental control features.

ClearPlay seems to be the most successful product of this type. A shareware Cine-bit DVD Player did this, but it has been withdrawn apparently because of legal threats from Nissimwho seem determined to stifle the very market they claim to support.

A Canadian company, Select Viewingis releasing software for customized DVD playback on Windows PCs. A few similar projects are under development. Yet another option is TVGuardiana device that attaches between the DVD player and the TV to filter out profanity and vulgar language.

The box reads the closed caption text and automatically mutes the audio and provides substitute captions for objectionable words. Note that current versions of these devices don't work with digital audio connections, and don't work with DVDs without NTSC Closed Captioning.

There's a euphemism in the DVD industry, where "multi-angle titles" --spoken with the right inflection-- means adult titles. However, apart from thousands of XXX-rated discs, not very many mainstream DVDs have multiple angles, since it takes extra work and limits playing time a segment with two angles uses up twice as much space on the disc.

Short Cinema Journal vol. Ultimate DVD Gold or Platinum is another sample disc with examples of angles. Deja Vroom has excellent angles, allowing you to focus on any of the musicians.

Other multi-angle music discs include Dave Matthews Band: Listener Supported, Metallica Cunning Stunts, Sarah McLachlan Mirrorball. Some movies, such as Detroit Rock City KISS videoGhostbusters SE, Mallrats, Suicide Kings, Terminator 2 SE, and Tomorrow Never Dies SE use multiple angles in supplements.

Some discs, especially those from Buena Vista, use the angle feature to show credits in the selected language usually with the angle key locked out.

You can get an incomplete list of multi-angle discs by doing an extended search at DVD File or other sites with searchable databases see 1. It depends on the label. If a label or adhesive strip is heavy enough it can unbalance the disc and cause read errors or slow down the disc speed.

This is especially a problem with magnetic strips for library or rental store security. As DVD-ROM drives get faster and faster, an unbalanced becomes more critical. DVD players and drives are designed to compensate for unbalanced discs, so a thin, light label is usually ok.

Pressure-sensitive adhesives break down over time, or may be weak to begin with, so it's possible for a label to come loose while the disc is spinning and damage the player or drive. The best option is a ring-shaped "donut" label that goes around the center of the disc. As long as the circular label doesn't interfere with the player clamping onto the hub, it should be ok. If you have to use a non-circular sticker, place it as close to the center as possible to minimize unbalancing.

Placing a second sticker straight across from the center will also help. High-adhesion labels are best. Writing with a marker in the clear not reflective area at the hub is better than using a sticker, although there's not much room to write. It's best to write inside a mm diameter, since writing elsewhere with certain kinds of inks could possibly eat away the protective coating and damage the data layer underneath. In most cases a better alternative for security is a case that can only be opened with special equipment at the register or checkout counter.

Barcodes, stickers, and security strips can be placed on the case without endangering discs or players. This is especially good for double-sided discs, which have no space for stickers. There are full-size round labels designed to go on recordable CDs and DVDs, but they have been known to cause problems, especially if not applied smoothly and straight. A better but more expensive solution is to use an inkjet disc printer IMTOdixionPrimeraRimageTrace Affex with printable-surface discs.

Some drives have the HP LightScribe feature, where if you have software that supports LightScribe, and you use special LightScribe discs with a photosensitive side, after you record the disc you can put it back in the drive upside down to "etch" a label on the disc. If you do use adhesive paper "donut" labels, it's best to get one of the devices that helps you center the label on the disc. Closed Captions CC are a standardized method of encoding text into an NTSC television signal. The text can be displayed by a TV with a built-in decoder or by a separate decoder.

All TVs larger than 13 inches sold in the US since have Closed Caption decoders. Closed Captions can be carried on DVD, videotape, broadcast TV, cable TV, and so on.

Even though the terms caption and subtitle have similar definitions, captions commonly refer to on-screen text specifically designed for hearing impaired viewers, while subtitles are straight transcriptions or translations of the dialogue. Captions are usually positioned below the person who is speaking, and they include descriptions of sounds such as gunshots or closing doors and music.

Closed captions are not visible until the viewer activates them. Open captions are always visible, such as subtitles on foreign videotapes. Closed Captions on DVDs are carried in a special data channel of the MPEG-2 video stream and are automatically sent to the TV. You can't turn them on or off from the DVD player. Subtitles, on the other hand, are DVD subpictures, which are full-screen graphical overlays see 3.

One of up to 32 subpicture tracks can be turned on to show text or graphics on top of the video. Subpictures can also be used to create captions. To differentiate from NTSC Closed Captions and from subtitles, captions created as subpictures are usually called "captions for the hearing impaired.

If this is all too confusing, just follow this advice: To see Closed Captions, use the CC button on the TV remote. To see subtitles or captions for the hearing impaired, use the subtitle button on the DVD remote or use the onscreen menu provided by the disc. Don't turn both on at once or they'll end up on top of each other. Keep in mind that not all DVDs have Closed Captions or subtitles. Also, some DVD players don't reproduce Closed Captions at all.

See DVD File's A Guide to DVD Subtitles and CaptioningGary Robson's Caption FAQand Joe Clark's DVD Accessibility for more about Closed Captions. Note that DVD does not support PAL Teletext, the much-improved European equivalent of Closed Captions. These often have English-only soundtracks with BBFC censoring.

These often contain uncut or less cut versions of films. DVD players are simple computers. Each one has a software program that controls how it plays discs.

Since the software is stored on a chip, it's called firmware. Some players have flaws in their programming that cause problems playing certain DVDs. In order to correct the flaws, or in some cases to work around authoring errors on popular discs, the player must be upgraded with a replacement firmware chip. This usually has to be done in a factory service center, although some players can be upgraded simply by inserting a CD.

A few DVDs are designed specifically for testing and optimizing video and audio playback. Some also demonstrate special features of DVD:. Here are a few movies that work especially well for demonstrating DVD's video and audio quality:. Films on Disc has a list of ISF DVD citations -- examples of the best of the craft. Sensormatic and Checkpoint are two point-of-sale security systems. They use little metal tags inserted into DVD packaging to set off an alarm if you go through the sensors at the store entrance without having the tags deactivated during checkout.

The tags are placed in the packages at the replication plant so that it doesn't have to be done at the store. This is called source tagging. The tags are not placed on the discs themselves and have nothing to do with whether a DVD will play or not. There is RF-based technology that can make DVDs unplayable until they are passed through an activation field at checkout, but it hasn't been commercially deployed. There is one single DVD-Video standard. However, within the DVD-Video format there is a great deal of flexibility in the way discs can be created.

Different studios have come up with brand names for their particular implementations of advanced features. There's nothing extraordinary about any particular variation, other than a studio spending a lot of time and effort making it work well and promoting it.

These kinds of advanced DVDs should play on most players but may reveal more player bugs than standard discs see 1. Superbit DVDs, from Columbia TriStar, use a high data rate for the video to improve picture quality. Additional language tracks and other extras are left off the disc to make room for more video data and for a DTS audio track. In most cases the difference is subtle, but it does improve the experience on high-end players and progressive-scan displays.

Infinifilm DVDs, from New Line, let you watch a movie with pop-ups that direct you to extra content such as an interview, behind-the-scenes-footage, or historical information.

DisneyDVD is Walt Disney Studio's own name for DVDs with special features, but nothing especially more special than what other DVD producers put on their special edition discs. Most DVD players allow you to lock out discs above a certain rating see 1. The rating level is protected by a password so that children or spouses can't change it. If you don't know the password you won't be able to play some discs.

You might be able to clear the password by resetting the player see the user manual or unplugging it for a few days. In some cases you might be able to use the default password, or Otherwise you'll have to call the customer service number of the manufacturer and see if they can help you.

Make sure you speak in a deep voice so they don't think you are a kid trying to hack into his parents' player. There's almost no chance your DVD player can be infected with a virus of the kind that infect computer software. DVD players have simple computers in them that run commands from the disc as it plays, but memory is reset when you press Stop or eject the disc. The firmware in some DVD players can be upgraded by inserting a special disc see 1. X-ray machines such as those used for airport security have no effect on storebought DVDs or on DVDs that you have recorded R, RW, or RAM format.

Your player is telling you that there are multiple camera angles or multiple video views on the disc. You can use the "Angle" key on the remote control to switch angles.

On some players you need to press the "Info" or "Display" key to bring up an on-screen interface to change angles see your manual for details. You can turn off angle notification in the preferences or setup menu of some players, but on other players it can't be turned off.

DVD player sales exceeded VCR sales in DVD recorders see 1. DVDs have many advantages over tapes, such as no rewinding, quick access to any part of a recording, and fundamentally lower technology cost for hardware and disc production. Some projections show DVD recorder sales passing VCR sales in By VHS may be as dead as vinyl records were in CD-ROMs and recordable CDs will probably never disappear since they are cheaper and can be use instead of DVD when the extra capacity isn't needed.

Likewise CD audio discs will probably never be replaced by DVD-Video or DVD-Audio discs since CDs are cheap and simple to make. However, DVD-ROM drives and recordable DVD drives will eventually replace CD-ROM drives and CD-RW drives in computers.

Most manufacturers plan to cease CD drive production in favor of DVD drives once they are cheap enough. Because DVD-ROM drives can read CD-ROMs, and because DVD recordable drives can write CD-R and CD-RW discs, there is a compatible forward migration path. The Blu-ray Disc BD format, released inwas developed by most of the same companies that developed DVD. It's the next generation "HD" version of DVD, where HD means both high definition better video and audio and high density more storage capacity.

BDs come in and Gbyte capacities, which can easily hold hours of high-definition video at resolutions of x or x with multichannel audio tracks in compressed or uncompressed format. The interactivity of DVD has been significantly extended for BD, with menus that can pop up over the video as it plays. A version of the Java programming language is built into every BD player, so BDs can include games and other sophisticated programs.

There is also an Internet-connected version, called BD-Live. BD-Live discs require a BD-Live player to work. Jim has been working on a BD FAQ for several years now but hasn't found time to get it into shape to post.

In the meantime you can buy his book, Blu-ray Disc Demystifiedor see Hugh Bennett's Blu-ray Disc BD FAQ for more information. You can't play BDs in a DVD player. You can play DVDs and CDs in a BD player. In other words, if you want to move to high-definition movies on BD you will need a new player, but your collection of DVDs will play just fine in the new player.

Next-generation DVD was actually under development before DVD came out but didn't begin to emerge untiland the formats were not used for movies until Some high-definition optical formats use the original DVD physical format but depend on new video encoding technology such as H.

High-density formats use blue or violet lasers to read smaller pits, increasing data capacity to around 15 to 30 GB per layer. High-density formats use high-definition MPEG-2 video for compatibility with ATSC and DVB HD broadcasts, see 2. In earlyBlu-ray "won the war" and became the dominant HD optical format for entertainment when Toshiba officially threw in the towel for HD DVD.

Here's a summary of the contenders, some of which are still around. Next-generation discs do not play on standard DVD players. Even red-laser discs, which the player may be able to physically read, require new circuitry to decode and display the high-def video. Red-laser discs can play on DVD PCs with the right software for example, HD versions of DVDs using Microsoft HD-WMV were available in Blue-laser discs require new optical assemblies and controllers.

Next-generation players read standard DVDs as well as audio CDs. Blu-ray is a high-density physical format that holds 25 GB per layer using a blue-ultraviolet laser and a 0. Because of the 0. Blu-ray was initially intended for home recording, professional recording, and data recording. Sony released the first BD recorder in Japan in Aprilalthough it was designed for home recording only not for playing pre-recorded HD moviesand only worked with Japan's digital HD broadcast system.

Mass-market distribution of pre-recorded movies came later, after the read-only format, called BD-ROM, was developed. Primary Blu-ray backers were Dell, Hitachi, HP, LG, Panasonic, Philips, Pioneer, Mitsubishi, Samsung, Sharp, Sony, and Thomson. The physical discs uses phase-change groove recording on a cm diameter, 1. Recording capacity on a single layer is about 2 hours of HD video at 28 Mbps or about 10 hours of standard-definition video at 4.

The DVD Forum developed a next-generation format, initially called Advanced Optical Disc AOD and later christened HD DVD. HD DVD is a modification of the original DVD physical format to enable about 15 GB per layer using a blue-ultraviolet readout laser to handle smaller pits and closer tracks.

HD DVD is designed to improve data capacity while theoretically being able to use existing replication equipment. It was primarily supported by Toshiba and Microsoft, with Intel jumping on board late in the game.

There was also a subformat called HD DVD-9 that put HD DVD video on standard, dual-layer DVD-9 discs. It was essentially a compatible-but-cheaper-to-replicate companion to blue-laser HD DVD. A 2-hour movie can fit on a DVD-9 at data rates of 6 to 7 Mbps. Shorter movies could be encoded in p24 format. Although Toshiba and the DVD Forum abandoned HD DVD in earlythe format lives on in China.

The DVD Forum licensed the specifications to the China High Definition DVD Industry Association CHDAwhich is developing a China High Definition DVD CH-DVD format by adding home-grown audio and video encoding formats. CH-DVD uses a different modulation technique, which makes the discs incompatible with other HD DVD players. WMV HD isn't really a new format.

Microsoft's high-definition video format came on standard dual-layer DVDs and played in Windows PCs with enough power 2. As of about 40 titles were available in WMV HD format, usually with both a standard DVD and a WMV HD DVD in the package.

This was an interim format that disappeared after HD DVD and BD came out, but it's still a viable option for publishing high-definition video on DVD. A government-backed consortium of companies in China, called eWorld, developed a domestic version of DVD called EVD Enhanced Versatile Disc. EVD is an aggressive program to standardize on technology developed within China, but in order to realistically release products, the early phases borrow from existing standards.

EVD players released in December used standard red lasers and MPEG HD video, along with China's own ExAC audio format. The plan was to switch to a Chinese video format, AVS, inbut as ofAVS was still not finalized. Future versions were planned to use multilevel red laser and multilevel blue laser recording, where the pit depth is varied to achieve higher density, but the EVD format never achieved much success and is fading out. EVD was ostensibly developed to reduce reliance on and cost of non-Chinese patents, but ironically all EVD players play DVD, so nothing has changed in the short term.

The Advanced Optical Storage Research Alliance AOSRAformed by Taiwan's Industrial Technology Research Institute ITRI developed its own tweaked red-laser format called Forward Versatile Disc FVD. The track pitch was reduced from 0. Microsoft's WM9 is used for video and audio encoding.

So far even Taiwanese companies seem to be paying more attention to BD than FVD. AOSRA also developed its own variations of 0. This was the burning question for many years as HD DVD and Blu-ray duked it out in the marketplace and court of public opinion. The question has been answered, but it's left here in the FAQ for historical flavor. Before Januaryno one really knew the answer to this question despite myriad strong opinions. Blu-ray had more consumer companies supporting it, but HD DVD was cheaper and had Microsoft behind it.

What made it uncertain was that the Hollywood studios were split roughly between the two formats, with Warner Bros. But on January 4,Warner completely changed the game when it announced that it would support Blu-ray exclusively after May. Successful formats are driven by content, and suddenly Blu-ray had the lion's share of the content. Rumors circulated that Toshiba and Sony had each offered increasingly large payments to Warner, and that Toshiba thought it had won the tussle by getting Fox to switch to HD DVD, which would have brought Warner off the fence.

Given Fox's strong support for Blu-ray from early on, parts of this story are hard to swallow, but Sony was apparently writing large checks in an effort to end the stalemate and get on with business.

Toshiba execs were clearly shell-shocked by Warner's announcement, cancelling their planned CES press conference and recalling execs to Japan. On February 19, Toshiba officially announced that it would stop making HD DVD players and would focus on other areas such as flash memory. Later, in an about-face that smacked of sour grapes, Toshiba introduced high-powered hardware that it claimed could make standard DVDs look as good as HD. This is actually many questions with many answers, covered in the following sections.

All DVD players and drives will read audio CDs Red Book. This is not actually required by the DVD spec, but so far all manufacturers have made their DVD hardware read CDs. On the other hand, you can't play a DVD in a CD player. The pits are smaller, the tracks are closer together, the data layer is a different distance from the surface, the modulation is different, the error correction coding is new, etc.

Also, you can't put CD audio data onto a DVD and have it play in DVD players. Red Book audio frames are different than DVD data sectors. All DVD-ROM drives will read CD-ROMs Yellow Book. Software on a CD-ROM will run fine in a DVD-ROM system.

The problem is that most CD-Rs Orange Book Part II are "invisible" to DVD laser wavelength because the dye used to make the CD-R doesn't reflect the beam. Some first-generation DVD-ROM drives and many DVD players can't read CD-Rs. The formulation of dye used by different CD-R manufacturers also affects readability.

That is, some brands of CD-R discs have better reflectivity at DVD laser wavelength, but even these don't reliably work in all players.

The common solution is for the DVD player or drive to use two lasers at different wavelengths: Variations on the theme include Sony's "dual discrete optical pickup" with switchable pickup assemblies with separate optics, dual-wavelength lasers initially deployed on Sony's Playstation 2Samsung's "annular masked objective lens" with a shared optical path, Toshiba's similar shared optical path using an objective lens masked with a coating that's transparent only to nm light, Hitachi's switchable objective lens assembly, and Matsushita's holographic dual-focus lens.

The MultiRead logo guarantees compatibility with CD-R and CD-RW media, but unfortunately, few manufacturers are using it.

If you want a DVD player that can read CD-R discs, look for a "dual laser," "twin laser," or "dual optics" feature. An effort to develop CD-R "Type II" media compatible with both CD and DVD wavelengths was abandoned. Most newer recordable DVD drives see 4. CD-R burners can't read or write DVD discs of any kind. There are no "upgrades" to convert CD-R drives to DVD-R, since this would cost more than purchasing a new DVD-R drive.

CD-Rewritable Orange Book Part III discs have a smaller reflectivity difference, requiring new automatic-gain-control AGC circuitry in CD-ROM drives and CD players. Most existing CD-ROM drives and CD players can't read CD-RW discs. The OSTA MultiRead standard addresses this, and some DVD manufacturers have suggested they will support it. The optical circuitry in even first-generation DVD-ROM drives and DVD players is usually able to read CD-RW discs, since CD-RW does not have the "invisibility" problem of CD-R see 2.

It's not required by the DVD spec, but it's trivial to support the Video CD White Book standard since any MPEG-2 decoder can also decode MPEG-1 from a Video CD. About two thirds of DVD players can play Video CDs. Most Panasonic, RCA, Samsung, and Sony models play Video CDs.

Japanese Pioneer models play Video CDs but American models older than the DVL don't. Toshiba players older than models, and don't play Video CDs. VCD resolution is x for PAL and x for NTSC.

The way most DVD players and Video CD players deal with the difference is to chop off the extra lines or add blank lines. Sony NTSC players scale all lines to fit. Playing time is shorter, and the audio is shifted up in pitch unless it was digitally processed before encoding to shift the pitch back to normal.

This also happens with PAL DVDs see 1. Many Asian VCDs carry two soundtracks by putting one language on the left channel and another on the right.

The two channels are mixed together into babel on a stereo system unless you adjust the balance or disconnect one input to get only one channel. For more on Video CD, see Glenn Sanderse's Video CD FAQ at CDPageor Russil Wvong's Video CD FAQ. Super Video CD SVCD is an enhancement to Video CD that was developed by a Chinese government-backed committee of manufacturers and researchers, partly to sidestep DVD technology royalties and partly to create pressure for lower DVD player and disc prices in China.

The final SVCD spec was announced in Septemberwinning out over C-Cube's China Video CD CVD and HQ-VCD from the developers of the original Video CD. In terms of video and audio quality, SVCD is in between Video CD and DVD, using a 2x CD drive to support 2. As with DVD, it can overlay graphics for subtitles. It's technically easy to make a DVD-Video player compatible with SVCD, but it's being done mostly on Asian DVD player models. The Philip's DVD player can be upgraded using a special disc to play SVCD discs.

See Jukka Aho's Super Video CD Overview and Super Video CD FAQ for more info. Because Picture CDs and Photo CDs are usually on CD-R media, they suffer from the CD-R problem see 2. That aside, some DVD players can play Picture CDs. Only a few can play Photo CDs.

Most DVD-ROM drives will read Picture CDs or Photo CDs if they read CD-Rs since it's trivial to support the XA and Orange Book multisession standards. Picture CDs are designed to work with Windows. Photo CDs require specific support from an application or an OS.

Photos can be put on recordable DVDs using the DVD-Video slideshow feature, which works on all DVD players. DVD players do not play CD-i Green Book discs. Philips once announced that it would make a DVD player that supported CD-i, but it never appeared.

Some people expected Philips to create a "DVD-i" format in an attempt to breathe a little more life into CD-i and recover a bit more of the billion or so dollars they invested in it. A DVD-ROM PC with a CD-i card should be able to play CD-i discs. There are also "CD-i movies" that use the CD-i Digital Video format that was the precursor to Video CD. Early CD-i DV discs won't play on DVD players or VCD players, but newer CD-i movies, which use the standard VCD format, will play on any player that can play VCDs see 2.

DVD players will play music from enhanced music CDs Blue Book, CD Plus, CD Extraand DVD-ROM drives will play music and read data from enhanced CDs. Most DVD players don't support this mostly obsolete format.

CDV, sometimes called Video Single, is actually a weird combination of CD and laserdisc. Part of the disc contains 20 minutes of digital audio playable on any CD or DVD player. The other part contains 5 minutes of analog video and digital audio in laserdisc format, playable only on a CDV-compatible laserdisc player. MP3 is the MPEG Layer 3 audio compression format. MP3 is not MPEG-3, which doesn't exist.

The DVD-Video spec allows only Layer 2 for MPEG audio MP2. However, MP3 files can be played from DVD on any computer with a DVD-ROM drive, and many DVD players particularly those manufactured in Asia can play MP3 CDs.