DVD-Video is a consumer video format used to store digital video on . DVD-Video was the dominant consumer home video format in Asia, North America, Europe, and Australia in the 2000s until it was supplanted by the high-definition Blu-ray Disc, before eventually both were replaced by streaming services such as Netflix and Disney+. Discs using the DVD-Video specification require a DVD drive and an MPEG-2 decoder (e.g., a DVD player, or a computer DVD drive with a software DVD player). Commercial DVD movies are encoded using a combination of MPEG-2 compressed video and audio of varying formats (often multi-channel formats as described below). Typically, the data rate for DVD movies ranges from 3 to 9.5 Mbit/s, and the bit rate is usually adaptive. DVD-Video was first available in Japan on November 1, 1996 (with major releases beginning December 20, 1996), followed by a release on March 26, 1997, in the United States—to line up with the 69th Academy Awards that same day.
The DVD-Video specification was created by DVD Forum and can be obtained from DVD Format/Logo Licensing Corporation for a fee of $5,000.DVD FLLC (2009) "DVD Format Book". Retrieved 2009-08-14.DVD FLLC (2009) "How to Obtain DVD Format/Logo License (2005–2009)". Retrieved 2009-08-14. The specification is not publicly available and every subscriber must sign a non-disclosure agreement. Certain information in the DVD Book is proprietary and confidential.
The following formats are allowed for H.262/MPEG-2 Part 2 video:
The following formats are allowed for MPEG-1 video:
The MPEG-1 Part 2 format does not support interlaced video. The H.262/MPEG-2 Part 2 format supports both interlaced and progressive-scan content, and can handle different frame rates from the ones mentioned above by using pulldown. This is most commonly used to encode 23.976 frame/s content for playback at 29.97 frame/s. Pulldown can be implemented directly while the disc is mastered, by actually encoding the data on the disc at 29.97 frames/s; however, this practice is uncommon for most commercial film releases, which provide content optimized for display on progressive-scan television sets.
Alternatively, the content can be encoded on the disc itself at one of several alternative frame rates, and use flags that identify scanning type, field order and field repeating pattern. Such flags can be added in video stream by the H.262/MPEG-2 Part 2 encoder. A DVD player uses these flags to convert progressive content into interlaced video in real time during playback, producing a signal suitable for interlaced TV sets. These flags also allow reproducing progressive content at their original, non-interlaced format when used with compatible DVD players and progressive-scan television sets. "DVD Benchmark – Part 5 – Progressive Scan DVD". "Home Theater High Fidelity: A Beautiful Mind, Review".
DVDs can contain more than one channel of audio to go together with the video content, supporting a maximum of eight simultaneous audio tracks per video. This is most commonly used for different audio formats—DTS 5.1, AC-3 2.0 etc.—as well as for commentary and audio tracks in different languages.
"some dvd players cannot sustain high max bitrate" though note also they still encode video at 8 Mbps and to help prevent in the case of dirty or scratched discs.
In October 2001, aiming to improve picture quality over standard editions, Columbia TriStar Home Entertainment offered "Superbit"—a premium line of DVD-Video titles having average bitrates closer to 6 Mbit/s. Audio quality was also improved by the mandatory inclusion of both Dolby Digital and DTS 5.1 surround audio tracks. Multiple languages, angles, and extra audio tracks were eliminated to free up more space for the main title and thereby to ensure the highest data rate possible. In January 2007 the Superbit line was discontinued.
Some hardware players will also play DVD-ROMs or containing "raw" MPEG video files; these are "unauthored" and lack the Computer file and header structure that defines DVD-Video. Standard DVD-Video files contain extra information (such as the number of video tracks, chapters and links to extra features) that DVD players use to navigate the disc.
The maximum chapters allowed per title is 99 and the maximum titles allowed per DVD is 99.
VOB files store control and playback information – e. g. information about chapters, subtitles and audio tracks. They do not store any video or audio data or subtitles.
VOB files are only backups of the IFO files.
can use DVD-VR or DVD+VR format instead of DVD-Video. DVD-VR format store multiplexed audiovisual content in VRO containers.DVD Demystified (July 13, 2009) "What Are .IFO, .VOB, .AOB, and .VRO files? How Can I Play Them?" . Retrieved 2009-07-28.Doom9’s forum (2002–2005) DVD-RAM *.VRO File Conversion, Retrieved 2009-07-28. VRO file is an equivalent to a collection of DVD-Video VOB files. "DVD-VR Application Format Notes. Retrieved 2009-07-28. Fragmented VRO files are not widely supported by hardware or software players and video editing software. DVD+VR standard defines a logical format for DVD-Video compliant recording on optical discs and is commonly used on DVD+R/RW media.
DVD-Video may also contain closed captioning material which can only be viewed on a television set with a decoder.
Extra features often provide entertainment or add depth and understanding to the film. Games, , and galleries provide entertainment. Deleted scenes and alternative endings allow the audience to view additional content which was not included in a theatrical release. Directors cuts allow the audience to see how the director envisioned the main title without the constraints which are placed on a theatrical release.
Other extras that can be included on DVDs are motion menus, still pictures, up to 32 selectable subtitles, seamless branching for multiple storylines, up to 9 camera angles, and DVD-ROM / data files that can be accessed on a computer.
Extra features require additional storage space, which often means encoding the main title with lower than possible data rate to fit both the main title and the extras on one disc. Lower data rate may decrease visual and sound quality, which manifests itself in various compression artifacts. To maintain quality the main title and the extras may be released on several discs, or the extras may be omitted completely like in the "Superbit" line of DVDs.
CSS does not make it difficult (any more) to copy the digital content now that a decoder (DeCSS) has been released, nor is it possible to distinguish between legal and illegal copies of a work, but CSS does restrict the playback software that may be used.
CSS has caused major problems for the inclusion of DVD players in any open source operating systems, since open source player implementations are not officially given access to the decryption keys or license to the involved in CSS. Proprietary software players were also difficult to find on some platforms. However, a successful effort has been made to write a decoder by reverse engineering, resulting in DeCSS. This has led to long-running legal battles and the arrest of some of those involved in creating or distributing the DeCSS code, through the use of the controversial U.S. Digital Millennium Copyright Act (DMCA), on the grounds that such software could also be used to facilitate unauthorized copying of the data on the discs. The Videolan team, however, went on to make the libdvdcss library. Unlike DeCSS, libdvdcss can access a CSS-encrypted DVD without the need of a cracked key, thus enabling playback of such discs on opensource players without legal restraints (although DVD rippers using this library may still be subject to restrictions).
The DMCA currently affects only the United States, however many other countries are signatories to the similar WIPO Treaty. In some countries it is not illegal to use de-scrambling software to bypass the DVD restrictions. A number of software programs have since appeared on the Web to view DVDs on a number of different platforms.
Other measures such as anti-ripping, as well as U.S. and non-U.S. copyright law, may be used to prevent making unauthorized copies of DVDs. CSS decrypting software, or ripping software, such as DVD Decrypter, AnyDVD, MacTheRipper, and DVD Shrink allows a disc to be copied to hard disk unscrambled. Some DeCSS applications also remove Macrovision, regional lockout, and disabled user operations (UOPs).
In practice, many DVD players allow playback of any disc, or can be modified to do so. Entirely independent of encryption, region coding pertains to regional lockout, which originated in the video game industry.
From a worldwide perspective regional coding may be seen as a failure. A huge percentage of players outside of North America can be easily modified (and are even sold pre-modified by e-commerce websites) to ignore the regional codes on a disc. This, coupled with the fact that almost all televisions in Europe and Australasia are capable of displaying NTSC video (at the very least, in black and white), means that consumers in these regions have a huge choice of discs. Contrary to popular belief, this practice is not illegal and in some countries that strongly support free trade it is encouraged.
A normal DVD player can only play region-coded discs designated for the player's own particular region. However, a code-free or region-free DVD player is capable of playing DVDs from any of the six regions around the world.
The CSS license prohibits manufacturing of DVD players that are not set to a single region by default. While the same license prohibits manufacturers from including prominent interfaces to change the region setting it does not clearly prevent them from including "hidden" menus that enable the player's region to be changed; as such, many high-end models in the U.S. include password-protected or otherwise hidden methods to enable multi-region playback. Conversely in the UK and Ireland many cheap DVD players are multi-region while more expensive systems, including the majority of home cinema systems, are preset to play only region 2 discs.
In China, DVDs for television series are usually released in MPEG-1 video, with MP2 audio. By forgoing Dolby standards, manufacturers cut costs considerably; encoding in lower bit-rates also allows a TV series to be squeezed onto fewer discs. There is no region coding in such cases.
There are also two additional region codes, region 7, which is reserved, and region 8, which is used exclusively for passenger transport such as airlines and cruise ships.
DVD drives for computers usually come with one of two kinds of Regional Playback Control (RPC), either RPC-1 or RPC-2. This is used to enforce the publisher's restrictions on what regions of the world the DVD can be played. (See Regional lockout and DVD region codes.) While open-source software DVD players allow everything, commercial ones (both standalone models and software players) come further encumbered with restrictions forbidding the viewer from skipping (or in some cases fast-forwarding) certain content such as copyright warnings or advertisements. (See User operation prohibition.)
When DVD drives first became commercially available in 1997, they often came with special encoder/decoder cards, which were designed to pass through either the integrated video on the computer motherboard or the video card. The cards were necessary since most computers did not have sufficient processing power to handle the decoding on the discs. As CPU speeds and video card memory drastically increased in the late 1990s, in addition to software alternatives such as PowerDVD becoming readily available, the decoder cards quickly became obsolete; however, before the introduction of GPU video encoding technology (such as Intel Quick Sync Video), a proprietary MPEG2 / MPEG4 encoder card may be used.
Video game systems with DVD-Video playback functionality include: Panasonic Q (a variation of the GameCube sold exclusively in Japan), PlayStation 2, PlayStation 3, PlayStation 4, PlayStation 5, Wii (with an unsupported hack), Xbox (additional remote required), Xbox 360, Xbox One, and Xbox Series X.
On November 18, 2003, the Chinese news agency Xinhua reported the final standard of the Chinese government-sponsored Enhanced Versatile Disc (EVD) which is another extension of standard DVD. Shortly thereafter the development of the format was halted by a licensing dispute between Chinese companies and On2 Technologies, but on December 6, 2006, 20 Chinese electronic firms unveiled 54 prototype EVD players and announced their intention for the format to completely replace DVDs in China by 2008. However, due to a lack of sales, support for EVD was dropped by the Xinhua Bookstore in Wuhan, which was a major supporter of the format.
With HD DVD launched in March 2006 and Blu-ray launched in June of the same year, a format war started. Industry analysts likened the situation to the VHS/Betamax format war of the 1980s. At the time of their launch, consumer awareness of either high-definition format was severely limited, with the result that most consumers avoided both formats, already content with DVD. In February 2008, Toshiba capitulated, citing low demand for HD DVD and the faster growth of Blu-ray, and the inclusion of the format in the video game system PlayStation 3 (PS3), among other reasons. Toshiba ended production of their HD DVD players and discontinued promotion of the format, while the HD DVD movie release schedule concluded by June 2008.
After HD DVD was discontinued, Blu-ray became the de facto high-definition optical disc format. However, sales figures suggest that DVD is in no immediate danger of disappearing. All standard DVDs will play on existing Blu-ray players, making the switch to Blu-ray much easier than the switch from VHS to DVD. Moreover, some labels are cutting back on Blu-ray Disc releases in favor of DVD-Video, claiming that low sales do not justify the more expensive Blu-ray Disc format. In addition, a growing number of hardware vendors are enhancing their Blu-ray players with Internet connectivity for subscription-based video downloads.
Ultra HD Blu-ray is the latest version available, supporting 4K resolution content.
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