Hier finden Sie die aktuellen Infos zur DVD Technologie. Der
schwerpunkt liegt bei DVD-Video+Audio.
Eine deutsche Übersetzung ist in Vorbereitung.
www.home-cinema.de hier mehr über DVDPlayer speziell codefree und Macrovision off Player
www.home-cinema.com hier alles über progressive scan DVDPlayer (METROPOLIS MEDIA ONE)
www.dvd-info.com allgemeine Info Seite DVD AUDIO, VIDEO und Computeranwendung (DVD-ROM, DVD RAM)
This is the April 30, 1999 revision of the official Internet DVD FAQ for the
rec.video.dvd Usenet newsgroups. (See below for
what's new.)
Please send corrections, additions, and new questions to Jim Taylor <jtfrog@usa.net>.
DVD, which stands for Digital Video Disc, Digital Versatile Disc, or nothing, depending on whom you ask, is the next generation of optical disc storage technology. It's essentially a bigger, faster CD that can hold video as well as audio and computer data. DVD aims to encompass home entertainment, computers, and business information with a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and perhaps even video game cartridges. DVD has widespread support from all major electronics companies, all major computer hardware companies, and about half of the major movie and music studios, which is unprecedented and says much for its chances of success (or, pessimistically, the likelihood of it being forced down our throats).
It's important to understand the difference between DVD-Video and DVD-ROM. DVD-Video (often simply called DVD) holds video programs and is played in a DVD player hooked up to a TV. DVD-ROM holds computer data and is read by a DVD-ROM drive hooked up to a computer. The difference is similar to that between Audio CD and CD-ROM. DVD-ROM also includes recordable variations (DVD-R, DVD-RAM, DVD-RW, DVD+RW; see 4.3). Most people expect DVD-ROM to be initially much more successful than DVD-Video. Most new computers with DVD-ROM drives can also play DVD-Videos (see 6.1).
There's also the DVD-Audio format that was introduced in 1999 (see 1.23 and 3.6.1).
Note: Most discs do not contain all features (multiple audio/subtitle tracks, seamless branching, parental control, etc.), as each feature must be specially authored. Some discs may not allow searching or skipping.
Most players support a standard set of features:
* Must be supported by additional content on the disc.
Some players include additional features:
DVD has the capability to produce near-studio-quality video and better-than-CD-quality audio. DVD is vastly superior to videotape and generally better than laserdisc (see 2.8.). However, quality depends on many production factors. Until compression experience and technology improves we will occasionally see DVDs that are inferior to laserdiscs. Also, since large amounts of video have already been encoded for Video CD using MPEG-1, a few low-budget DVDs will use that format (which is no better than VHS) instead of higher-quality MPEG-2.
DVD video is compressed from digital studio master tapes to MPEG-2 format. This "lossy" compression 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 "artifacts" such as blockiness, fuzziness, and video noise depending on the processing quality and amount of compression. At average rates of 3.5 Mbps (million bits/second), compression artifacts may be occasionally noticeable. 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 was not originally present 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 or picture enhancement, poor film-to-video transfer, film grain, player faults, disc read errors, etc. 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 not an indication that DVD quality is bad, since other demos show no artifacts or other problems. Bad demos are simply an indication of how bad DVD can be if not properly processed and correctly reproduced. Many demo discs were rushed through the encoding process in order to be distributed as quickly as possible. Contrary to common opinion, and as stupid as it may seem, these demos are not carefully "tweaked" to show DVD at its best. 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 for a CD causes it to sound harsh. Many DVD players output video with a black-level setup of 0 IRE (Japanese standard) rather than 7.5 IRE (US standard). On TVs that are not properly adjusted this can cause some blotchiness in dark scenes. DVD video has exceptional color fidelity, so muddy or washed-out colors are almost always a problem in the display, not in the DVD player or disc.
DVD audio quality is excellent. One of DVD's audio formats is LPCM (linear pulse code modulation) 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 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.
The final assessment of DVD quality is in the hands of consumers. Most viewers consistently rate it better than laserdisc, but no one can guarantee the quality of DVD, just as no one should dismiss it based on demos or hearsay. In the end it's a matter of individual perception and the level of quality delivered by the playback system.
Some manufacturers originally announced that DVD players would be available as early as the middle of 1996. 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.
Available players:
Projected player releases:
Fujitsu supposedly released the first DVD-ROM-equipped computer on Nov. 6 in Japan.
Toshiba released a DVD-ROM-equipped computer and a DVD-ROM drive in Japan in early 1997
(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 January 1997, but none were to be available before May. Creative Labs' PC-DVD
upgrade kit (Matsushita drive and A/V decoder board; Warner DVD-V sampler) went on sale in
the U.S. in April 1997 for $500. Samsung drives (and PCs with drives) were available in
Korea in January. Hi-Val's $799 PC-DVD upgrade kit (Toshiba drive, Quadrant decoder; 6
DVD-ROMS including Silent Steel, Daedalus Encounter, and Xiphias Encyclopedia Electronica)
became available in May 1997, as did Diamond Multimedia's $599 kit. STB Systems DVD
Theater Upgrade Kit was be available in July for $699. DynaTek announced a $649 upgrade
kit with 6 titles. Toshiba's Infinia DVD-ROM-equipped PC become available Summer 1997.
Creative's new "Encore" 2x DVD-ROM kit is available for under $100. Hi-Val's
2nd-generation kit is $380. E4's CoolDVD upgrade kit for Macintoshes became available for
$499 in July 1998. Sigma Designs also makes playback cards.
For drive details see http://www.brouhaha.com/~eric/video/dvd/.
WebShopper has a good report
(dated Sep 16, 1998).
Note: If you buy a player or drive from outside your country (e.g., a Japanese player for use in the US) you may not be able to play region-locked discs on it. (See 1.10.)
As with hardware, rosy predictions of hundreds of movie titles for Christmas of 1996 failed to materialize. Only a handful of DVD titles, mostly music videos, were available in Japan for the November 1996 launch of DVD. Actual feature films began to appear in December. By April there were over 150 titles in Japan. Movies appeared in the US in March of 1997. Currently (Apr 1998) there are about 800 titles available in the US and over 1200 worldwide. Compared to other launches (CD, LD, etc.) this is a huge number. Almost 19,000 discs were purchased in the first two weeks of the US launch -- more than expected. InfoTech predicted over 600 titles by the end of 1997 and more than 8,000 titles by 2000. By December 1997, over 1 million individual DVD discs were shipped.
A concerted launch of DVD hardware and software in Europe is planned for the second quarter of 1998. Over 100 titles are expected to be available by March, with over 250 available by the end of 1998. Time Warner's official launch of DVD in Australia (region 4) is planned for Easter of 1998.
For an extensive, searchable list of titles available in the US and Canada see Jeff Phillips' list at <http://www.thedvdlist.com/>. For titles in Japan and Europe see Niels van Eijkelenburg's list at <http://www.surroundfreak.com/dvd/dvd2.htm> or Robert's list at <http://www.unik.no/~robert/hifi/dvd/film2.html>. Also check out the Internet Movie Database's DVD Browser <http://us.imdb.com/Sections/DVDs>. Christoph Steinecke's extensive list of region 1 titles is at <http://www.surroundfreak.com/dvd/dvd1.htm>. New release lists and announcements are available at <http://www.image-entertainment.com/laserv.html>. For a list of widescreen-specific DVD titles, visit http://www.widescreenreview.com/>.
Concorde Video released a PAL-format 12 Monkeys in Germany at the end of March 1997. They were threatened by Philips with a lawsuit for not including a multichannel MPEG track, but the issue is now resolved (see 3.6).
DVD-ROM software will slowly appear. Approximately 50% of CD-ROM producers have announced intentions to develop for DVD-ROM. See 6.2 for a list. Many initial DVD-ROM titles are only be available as part of a hardware or software bundle until the market grows larger. IDC expects that over 13 percent of all software will be available in DVD-ROM format by the end of 1998. In one sense, DVD-ROMs are simply larger faster CD-ROMs and will contain the same material. 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.
Mass-market DVD movie players currently list for $300 and up. (See 1.5 for models and prices.) Within a few years they may approach VCR prices. InfoTech predicts prices will be as low as $250 by the year 2000, and below $150 by 2005.
DVD-ROM drives and upgrade kits for computers sell for around $80 to $600. (OEM drive prices are under $70.) Prices are expected to drop quickly to current CD-ROM drive levels.
It varies, but most DVD movies list for $20 to $30 with street prices between $15 and $25, even those with supplemental material. Low-priced movies can be found for under $10. So far DVD has not followed the initial high rental price model of VHS.
DVD-ROMs will initially be slightly more expensive than CD-ROMs since there is more on them, they cost more to replicate, and the market is smaller. But once production costs drop and the installed base of drives grow, DVD-ROMs will cost about the same as CD-ROMs today.
Not as fast as generally predicted, but faster than videotape, laserdisc, and CD. By the end of 1997 over 500,000 DVD-Video players shipped worldwide. 349,482 of these were in the US (with about 200,000 actually sold into homes). About ?? DVD video titles were available worldwide, with ?? million copies shipped. About 600 DVD video titles were available in the US, with over 5 million copies shipped and about 2 million sold. Around 330,000 DVD-ROM drives were shipped worldwide with about 1 million bundled DVD-ROM titles. Only 60 DVD-ROM titles were available by the end of 1997, most of them bundled with PCs or drive upgrade kits.
Here are some predictions:
Here's reality:
For comparison, there are about 700 million audio CD players and 160 million CD-ROM drives worldwide in 1997. 1.2 billion CD-ROMs were shipped worldwide in 1997 from a base of about 46,000 different titles. There are about 80 million VCRs in the U.S. (89% of households) and about 400 million worldwide. 110,000 VCRs shipped in the first two years after release. Nearly 16 million VCRs were shipped in 1998. There are about 3 million laserdisc players in the U.S. There are about 250 million TVs in the U.S. and 1.2 billion worldwide.
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.S. when it's just hitting screens in Europe). Also, studios sell distribution rights to different foreign distributors and would like to guarantee an exclusive market. Therefore they have required that the DVD standard include codes that can be used 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 allowed in that region. This means that discs bought in one country may not play on players bought in another country.
Regional codes are entirely optional for the maker of a disc. Discs without codes 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 will have regional codes, but so far almost all releases play in only one region. Region codes are a permanent part of the disc, they won't "unlock" after a period of time.
There are 6 regions (also called "locales"). Players and discs are identified
by the 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.
1: Canada, U.S., U.S. Territories
2: Japan, Europe, South Africa, Middle East (including Egypt)
3: Southeast Asia, East Asia (including Hong Kong)
4: Australia, New Zealand, Pacific Islands, Central America, Mexico, South America,
Caribbean
5: Former Soviet Union, Indian Subcontinent, Africa (also North Korea, Mongolia)
6: China
(See the map at <http://www.unik.no/~robert/hifi/dvd/world.html>.)
Some players can be modified to play discs regardless of their regional codes. This usually voids the warranty. Some discs, such as those from Buena Vista/Touchstone/Miramax, MGM/Universal, and Polygram contain program code that checks for the proper region. These discs won't play on "code-free" players that have their region set to 0, but they can be played on "code-switchable" players that allow you to change the region using the remote control. Information about modifying players can be found on the Internet (including sites such as Code Free DVD and <http://www.brouhaha.com/~eric/video/dvd/>) and in the rec.video.dvd newsgroups (searchable at Deja News).
Regional codes also apply to DVD-ROM systems, but are allowed for use only with DVD-Video discs, not DVD-ROM discs containing computer software. (See 1.11 below for more details). Computer playback systems check for regional codes before playing movies from a DVD-Video. Newer "RPC2" DVD-ROM drives let you change the region code several times. Once a drive has reached the limit (usually 5 to 9 changes) it can't be changed again unless the vendor or manufacturer resets it.
Regional codes will not apply to DVD-Audio.
There are four forms of copy protection used by DVD:
1) Analog CPS (Macrovision)
Videotape (analog) copying is prevented with a Macrovision 7.0 or similar circuit in every
player. The general term is APS (Analog Protection System). Computer video cards with
composite or s-video (Y/C) output must also use APS. Macrovision adds a rapidly modulated
colorburst signal ("Colorstripe") along with pulses in the vertical blanking
signal ("AGC") to the composite video and s-video outputs. This confuses the
synchronization and automatic-recording-level circuitry in 95% of consumer VCRs.
Unfortunately, it can degrade the picture, especially with old or nonstandard equipment.
Macrovision may show up as stripes of color, distortion, rolling, black & white
picture, and dark/light cycling. Macrovision creates severe problems for most line
doublers. Macrovision is not present on analog component video output of early players,
but is required on newer players (AGC only, since there is no burst in a component
signal). The discs contain "trigger bits" in the header of each sector telling
the player whether or not to enable Macrovision AGC, with the optional addition of 2-line
or 4-line Colorstripe. This allows fine control over which sections are copy protected.
The producer of the disc decides what amount of copy protection to enable and then pays
Macrovision royalties accordingly (a few cents per disc). Just as with videotapes, some
DVDs are Macrovision-protected and some aren't. (For a few Macrovision details see
STMicroelectronics' NTSC/PAL video encoder datasheets at <http://www.st.com/stonline/books/>.)
2) CGMS
Each disc also contains information specifying if the contents can be copied. This is a
"serial" copy generation management system (SCMS) designed to prevent copies or
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. The analog
standard (CGMS/A) encodes the data on NTSC line 21 (in the XDS service). The digital
standard (CGMS/D) is not yet finalized, but will apply to digital connections such as IEEE 1394/FireWire. See section 4, below.
3) Content Scrambling System (CSS)
Because of the potential for perfect digital copies, paranoid movie studios forced a
deeper copy protection requirement into the DVD-Video standard. Content Scrambling System
(CSS) is a form of data encryption to discourage reading media files directly from the
disc. Most players have a decryption circuit that decodes the data before displaying it.
No unscrambled digital output is allowed until work in progress for secure digital
connections is finished. On the computer side, DVD-ROM drives and video display/decoder
hardware or software exchange encryption keys so that the video is decrypted just before
being displayed by the encoder. This means that many DVD-ROM drives and video display
boards have extra hardware (and cost) for movie copy protection. In 1999, all DVD-ROM
drives will be required to support regional management in conjunction with CSS. Some
drives may allow the user to reset the region a limited number of times; other drives will
self-program after a certain number of movies have been played. Makers of equipment used
to display DVD-Video (drives, chips, display boards, etc.) must license CSS. There is no
charge for a CSS license, but it's currently a lengthy process, so it's recommended that
interested parties apply as soon as possible. Near the end of May 1997, CSS licenses were
finally granted for software decoding.
4) Digital Copy Protection System (DCPS)
In order to provide for digital connections between components without allowing perfect
digital copies, five digital copy protection systems have been proposed to CEMA. The frontrunner is DTCP (digital transmission content protection), which
focuses on IEEE 1394/FireWire but can be applied to other protocols. The draft proposal
(called 5C, for the five companies that developed it) was made by Intel, Sony, Hitachi,
Matsushita, and Toshiba in February 1998. In December 1998, Sony announced the development
of a DTCP chip planned for release in spring 1999. 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. The DVD player encrypts the
encoded audio/video signal as it sends it to the receiving device, which must decrypt it.
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 access), from Zenith and
Thomson, is similar to DTCP but can work with one-way digital interfaces (such as the
EIA-762 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." Digital CPS is designed for the next generation of digital TVs, digital
receivers, and digital video recorders. It will require new DVD players with digital
connectors (such as those on DV equipment). These new products won't appear before mid
1999. Since the encryption is done by the player, no changes are needed to the existing
disc format.
Movie studios and consumer electronics companies want to make it illegal to defeat DVD copy protection, and have promoted legislation in the U.S. and other countries. The result is the World Intellectual Property Organization (WIPO) Copyright Treaty and the WIPO Performances and Phonograms Treaty (December 1996) and the compliant U.S. Digital Millenium Copyright Act (DMCA), passed into law in October 1998. A co-chair of the legal group of the 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." It's not at all clear how this might be "permitted" by a player or by studios that set the "don't copy" flag all their discs.
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. Computers with IEEE 1394/FireWire connections must
support the final DCPS standard in order to work with other DCPS devices. Every DVD-ROM
drive must include CSS circuitry to establish a secure connection to the decoder hardware
or software in the compute, 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 first three forms of copy protection are optional for the producer of a disc. Movie decryption is also optional for hardware and software playback manufacturers: a player or computer without decryption capability will only be able to play unencrypted movies. DCPS is performed by the DVD player, not by the disc developer.
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." Even the people who developed the copy protection standards admit that they won't stop well-equipped pirates. There are inexpensive devices that defeat analog copy protection, although only a few work with the new Macrovision Colorstripe feature. These devices go under names such as Video Clarifier, Image Stabilizer, and CopyMaster.
The Data-Hiding Sub-Group (DHSG) of the industry's Copy Protection Technical Working Group (CPTWG) is evaluating watermarking proposals. The original seven watermarking proposals that were merged into three: IBM/NEC, Hitachi/Pioneer/Sony, and Macrovision/Digimarc/Philips. On February 17, 1999, the first two groups combined to form the "Galaxy Group" and merged their technologies into a single proposal. Watermarking, which will be added to DVD at some point, permanently marks each digital video frame with noise that is supposedly visually undetectable. Watermark signatures can be recognized by video playback and recording equipment to prevent copying, even when the video is transmitted via digital or analog connections or is subjected to video processing. New players and other equipment will be required to support watermarking, but the DVD Forum intends to make watermarked discs compatible with existing players. There are reports that the watermarking technique used by Divx causes visible "raindrop" or "gunshot" patterns. The problem seems to have been solved with newer discs.
When DVD was released in 1996 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 January 1998, and version 0.9 was released in July. The final DVD-Audio 1.0 specification was approved in February 1999 and released in March. DVD-Audio products will show up in late 1999 at the earliest. The delay is being caused by the slow process of selecting copy protection features (encryption and watermarking). It's possible that the RIAA's Secure Digital Music Initiative (SDMI) could push the introduction of DVD-Audio into 2000.
DVD-Audio is a separate format from DVD-Video. DVD-Audio discs can be designed to work in DVD-Video players, but its possible to make a DVD-Audio disc that won't play at all in a DVD-Video player, since the DVD-Audio specification includes new formats and features, with content stored in a separate "DVD-Audio zone" on the disc (the AUDIO_TS directory) that DVD-Video players never look at. New DVD-Audio players are needed, or new "universal players" that can play both DVD-Video and DVD-Audio discs.
Plea to producers: Universal players won't be
available for some time, but you can make "universal discs" today. 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.
Plea to DVD-Audio authoring system developers: Make
your software do this by default or have it strongly recommend this option during
authoring.
DVD-Audio (and universal) players will 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 the high-definition PCM audio (see 3.6.1 for details), and even if they could it can't be carried on standard digital audio connections. DVD-Audio players with high-end digital-to-analog converters (DACs) can be hooked up to receivers with two-channel or 6-channel analog inputs, but some quality will be lost if the receiver converts back to digital for processing. Future receivers with improved digital connections such as IEEE 1394 (FireWire) will be required to use the full digital resolution of DVD-Audio.
The music industry has requested an "embedding signalling" or "digital watermark" copy protection 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. Audiophiles claim this degrades the audio.
In the meantime, the DVD-Video standard includes surround sound audio and better-than-CD audio (see 3.6.2).
Sony and Philips have developed a competing Super Audio CD format. (See 3.6.1 for details.) SACD provides "legacy" discs that have two layers, one that plays in existing CD players, plus a high-density layer for DVD-Audio players. Ironically, initial price for these dual-layer discs will be higher than for a standard CD plus a standard DVD. Sony released version 0.9 of the SACD spec in April 1998, the final version is expected in April 1999. SACD technology will be available to existing Sony/Philips CD licensees at no additional cost.
When DVD players became available in early 1997, Warner and Polygram were the only major movie studios to release titles. Additional titles were available from small developers. The other studios gradually joined the DVD camp (see 6.2 for a full list, see 1.6 for movie info).
Dreamworks was the last significant studio to announce full DVD support. Paramount, Fox, and Dreamworks initially supported only Divx, but in summer 1998 they each announced support for open DVD.
Short Answer: No. (Not in this century.)
Long answer: The minimum requirement for reproducing audio and video on DVD is an MPEG video stream and a PCM audio track. (Other streams such as Dolby Digital audio, MPEG audio, and subpicture are not necessary for the simplest case.) Basic DVD control codes are also needed. At the moment it's difficult in real time to encode the video and audio, combine them with DVD-V info, and write the whole thing to DVD. Even if you could do all this in a home recorder, it would be extremely expensive. Prices for DVD production systems are dropping from millions of dollars to thousands of dollars, but they won't be in the <$500 range for home use for several years yet. In June 1997, Hitachi demonstrated a home DVD video recorder containing a DVD-RAM drive, a hard disk drive (as a buffer), two MPEG-1 encoders, and an MPEG-2 decoder. No production date was mentioned. It's possible the first home DVD recorders will require a digital source of already-compressed audio and video, such as DBS.
Other obstacles: Price of blank discs initially will be $30 and up. The first generation of recordable media will hold less than 3/4 as much as prerecorded discs. Realtime compression requires higher bit rates for decent quality, lowering capacity even more. MPEG-2 compression works much better with high-quality source, so recording from VHS or broadcast/cable may not give very good results (unless the DVD recorder has prefilters, which raises the cost).
Don't be confused by DVD-R, which came out in Sep 1997 for $17,000; or DVD-RAM, which came out in June for around $500; or other recordable variations of DVD (see 4.3). These can record data, but to create full-featured DVD-Videos requires additional hardware and software to do video encoding (MPEG), audio encoding (Dolby Digital, MPEG, or PCM), subpicture encoding (run-length-compressed bitmaps), still frame encoding (MPEG), navigation and control data generation, and multiplexing. And since this can't yet be done in real time, you'd also need a 5 to 9 GB hard drive to premaster the data to.
Some people believe that recordable DVD-Video will never be practical for consumers to record TV shows or home videos, since digital tape is more cost effective. On the other hand, digital tape lacks many of the advantages of DVD such as seamless branching, instant rewind/fast forward, instant search, and durability, not to mention the coolness of small shiny discs. So once the encoding technology is fast and cheap enough, and the blank discs are cheap enough, recordable DVD may be a reality. It will be an interesting contest between DVD and digital video tape formats. DV (aka DVC) is out already, but decks cost $4,000. D-VHS and other Digital VCR technologies are just becoming available.
Most scratches will cause minor channel data errors that are easily corrected. 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!) is physically four times that of CD-ROM, so it's true that a scratch will affect more data. But DVD error correction is at least ten times better 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. Major scratches may cause uncorrectable errors that will cause an I/O error on a computer or show up as a momentary glitch in DVD-Video picture. There are many schemes for concealing errors in MPEG video, which may be used in future players (see section D.12 of <http://icib.igd.fhg.de/icib/it/iso/cd_13818-2/read1.html>).
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. So far most reports of rental disc performance are positive. A nice list of DVD rental outlets is at <http://www.dvdpost.com/rental.html>.
The primary advantages of DVD are quality and extra features (see 1.2). 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 "collectability" factor present with CDs vs. cassette tapes.
If none of this matters to you, then VHS probably is good enough.
Manufacturers are worried about customers assuming DVDs will play in their CD player, so they would like the packaging to be different. There are a number of DVD packages such as the "keep case" and Time Warner's "Snapper" that are about as wide as a CD jewel box and about as tall as a VHS cassette box. However, no one is being forced to use a larger package size and many companies will undoubtedly use standard jewel cases. It remains to be seen if any package becomes standard, especially for DVD-ROM.
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 readable from the same side, a dual-layer disc can hold almost twice as much as a single-layer disc, for over 4 hours of video (see 3.3 for more details). Many dual-layer discs are currently available (such as Contact, Goldeneye, Species, Raging Bull, and Rain Man). Initially only a few replication plants could make dual-layer discs, but most plants now have the capability. The second layer can either have a "PTP" track that runs in parallel to the first track (for independent data or special switching effects), or an "OTP" tracks that runs opposite to the first track; that is the pickup head reads out from the center on the first track then in from the outside on the second track. This is designed to provide continuous video across both layers. There's no guarantee that the switch between layers will be seamless. Non-seamless switches cause the video to freeze for less than half a second on most players but up to 4 seconds on some. The "seamlessness" depends as much on the way the disc is prepared as on the design of the player. OTP is also called RSDL (Reverse-Spiral Dual Layer). The advantage of OTP (RSDL) is that longer movies can use higher data rates for better quality than with a single layer. See 1.26 for layer change details.
All DVD players and drives can read dual-layer discs -- it's required by the spec. 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. The added cost is probably not justifiable 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 should no longer be a problem.) Pioneer LD/DVD players can play both sides of an LD, but not a DVD. (See 2.9 for note on reading both sides simultaneously.)
There are various ways to recognize dual-layer discs: 1) the gold color, 2) a menu on the disc for selecting the widescreen or letterbox version, 3) two serial numbers on one side.
DVD-V has the same NTSC vs. PAL problem as videotape and laserdisc. The MPEG video on DVD is stored in digital format, but it's formatted for one of two mutually incompatible television systems: 525/60 (NTSC) or 625/50 (PAL/SECAM). There are three differences between discs intended for playback on different systems: picture size and pixel aspect ratio (720x480 vs. 720x576), display frame rate (29.97 vs 25), and surround audio (Dolby Digital vs. MPEG). (See 3.4 and 3.6 for details.) Video from film is usually stored at 24 frames/sec but is preformatted for one of the two display rates. Movies formatted for PAL display are usually sped up by 4%, so the audio must be adjusted accordingly before being encoded. All PAL DVD players can play Dolby Digital audio tracks, but no NTSC players can play MPEG audio tracks.
Some players will only play NTSC discs, some players will only play PAL discs, and some will play both. All DVD players sold in PAL countries play both. These multi-standard players partially convert NTSC to a 60-Hz PAL (4.43 NTSC) signal, which requires a PAL TV that can handle 60-Hz signals. In this case the player uses the PAL 4.43 color encoding format but keeps the 525/60 NTSC scanning rate. Most modern PAL TVs can handle this kind of signal. A few multi-standard PAL players output true 3.58 NTSC from a 525/60 NTSC discs, which requires an NTSC TV or a multi-standard TV. Some players have a switch to choose between 60-Hz PAL and NTSC output when playing NTSC discs. It's also possible to make a standards-converting player that will output standard NTSC from a 625/50 disc or standard PAL from a 525/60 disc. A few players that convert 525/60 NTSC to 625/50 PAL have been announced.
A producer can choose to include additional video and audio --at the expense of playing time-- so that all formats are covered. It's unclear if players will be able to automatically recognize and play the correct video track. Of course it's always possible to put 525/60 video on one side of the disc and 625/50 on the other. Most studios so far are including Dolby Digital tracks along with the MPEG audio tracks on their PAL discs.
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.
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. Neither is true.
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 occur.
Even though DVD's dual-layer technology (see 3.3) allows over four hours of continuous playback, some movies are split over two sides of a disc, requiring that the disc be flipped partway through. 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 lame 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 1997 very few DVD plants could make dual-layer discs, but this is no longer the case. No 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 following discs are "flippers." (Note: This is not the same as a disc with a widescreen version on one side and a pan & scan version or supplements on the other.)
Answer: RTFM. You are watching an anamorphic picture intended for display only on a widescreen TV. (See 3.5 for technical details). You need to go into the player's setup menu and tell it you have a standard 4:3 TV, not a widescreen 16:9 TV. 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.
See Steve Tannehill's Why Does The Picture Look Squished? article for further explanation and pictures.
Most DVD-Video discs contain Dolby Digital soundtracks. However, it's not required. Some discs, especially those containing only audio, have PCM tracks. It's also possible for a 625/50 (PAL) disc to contain only MPEG audio, but so far MPEG audio is not widely used.
Don't assume that the "Dolby Digital" label is a guarantee of 5.1 channels. A Dolby Digital soundtrack can be mono, dual mono, stereo, Dolby Surround stereo, etc. For example, Blazing Saddles and Caddyshack are mono movies, so the 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: a 5.1-channel track and a track specially remixed for stereo Dolby Surround. It's perfectly normal for your DVD player to indicate playback of a Dolby Digital audio track while your receiver indicates Dolby Surround: it means that the disc contains a two-channel Dolby Surround signal encoded in Dolby Digital format.
See 3.6 for more audio details.
Laserdiscs are subject to what's commonly called laser rot: the deterioration of the aluminum layer due to oxidation. The large size of laserdiscs makes them flexible, so that movement along the bond between sides can break the seal. Like laserdiscs, DVDs are made of two platters glued together, but DVDs are more rigid and use newer adhesives. Also, DVDs are molded from polycarbonate, which absorbs about ten times less moisture than the PMMA used for laserdiscs. It's too early to know for sure, but DVD's will probably have few or no laser rot problems.
Some titles are available only in pan & scan because there was no letterbox or anamorphic transfer made from film. (See 3.5 for more info on pan & scan and anamorphic formats.) Since transfers cost $50,000 to $100,000, studios may not think a new transfer is justified. 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 1.37 "academy" aspect ratio so there can be no widescreen version. Video shot with TV cameras, such as music concerts, is already in 4:3 format.
The list of pan & scan only titles has gotten too big to keep here. You can get a list from the Internet Movie Database (which also includes discs with both widescreen and pan & scan versions), and you can search by screen format (which includes disc with video shot in fullscreen 4:3) at The DVD List.
On the remote control, press Subtitle, then either Clear or 0 (zero). No need to use the menus.
Some movies over 2 hours long may be spread across two layers on a disc. When the player changes to the second layer, the video and audio may freeze for a moment. The length of the pause depends on the player and on the layout of the disc. The pause is not a defect in the player or the disc. See 1.18 for details.
Layer switch points on RSDL discs:
Some discs (many from Columbia TriStar) put 2-channel Dolby Surround audio on track one and 5.1-channel audio on track two. Unless you intervene, the player will play the default 2-channel track. Use the audio button on the remote or select the 5.1 track from the menu. (Note: The Sony 3000 has a feature to automatically select the first 5.1 track.)
Dolby Digital doesn't necessarily mean 5.1 channels. See 3.6.
Almost all features of DVD such as search, pause, and scan can be disabled by the disc, which can prevent the operation the player needs to back up and repeat a segment. If the player uses time search to repeat a segment, then a disc with fancy non-sequential title organization may also block the repeat feature. In many cases the authors don't even realize they have prevented the use of this feature.
There is no good answer to this question, since you'll get a different response from everyone you ask. The terms "2nd generation" and "3rd generation" are used refer both to DVD-Video players and to DVD-ROM drives. In general, they simply mean newer versions of basic DVD playback systems. The terms haven't been used (yet) to refer to DVD systems that can record, play video games, or so on.
According to some people, second-generation DVD players came out in the fall of 1997 and third-generation players are those that came out in the beginning of 1998. According to others, the second generation of DVD will be "high-definition" players (see 2.9) that won't come out until 2003 or so. There are many confusing variations between these extremes, including the viewpoint that DTS-compatible players or Divx players or progressive-scan players constitute the third generation.
Things are a 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 4.8x or 6x) DVD-ROM drives, a few of which can read DVD-RAMs, and some of which are RPC2 format. See section 4.2 for more speed info. See section 1.10 for RPC2 explanation.
Hah, hah, hah! Do you really want the answer to this one? Ok, you asked for it...
Did I miss any?
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. See 3.6.2 for technical details. Some people claim that because of its lower compression level DTS sounds better than Dolby Digital. Others claim there is no meaningful difference. DTS discs are produced only by DTS, under license from movie studios, and are generally considered to be specialty items intended for audio enthusiasts. It's expected that discs produced by DTS will also be available in standard DVD format.
DTS is an optional format on DVD. The original DVD specification developed in 1996 provides an ID code for DTS, but players made before mid 1998 (and many since) ignore DTS tracks. A few demo discs were created by embedding DTS data into a PCM track (the same technique used with CDs and laserdiscs), and these are the only DTS DVD discs that work on all players. New DTS-compatible players arrived in mid 1998, but theatrical DTS discs using the DTS audio stream ID specified by the DVD-Video standard did not appear until January 7, 1999 (they were originally scheduled to arrive in time for Christmas 1997). Mulan, a direct-to-video animation (not the Disney movie) with DTS soundtrack did apear in November 1998. DTS-compatible players will carry an official "DTS Digital Out" logo. A few manufacturers may provide upgrades to make existing players compatible with DTS discs.
Dolby Digital or PCM audio are required on 525/60 (NTSC) discs, and since both PCM and DTS together don't usually leave enough room for quality video encoding, essentially every disc with a DTS soundtrack will also carry a Dolby Digital soundtrack. 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 will work on all DVD players, since the DTS data is encapsulated as standard PCM tracks that are passed untouched to the digital audio output(s).
You are probably trying to play an NTSC disc in a PAL player, but your PAL TV is not able to handle the signal. If your player has a switch or onscreen setting to select the output format for NTSC discs, choosing PAL (60-Hz) may solve the problem. See section 1.19 for more information.
Many DVD's are labeled as having widescreen (16:9) format video on one side and standard (4:3) on the other. If you think both sides are the same, you're probably seeing uncompressed 16:9 on the widescreen side. It seems to be 4:3 pan & scan, but if you look carefully you'll discover that the picture is horizontally compressed. The problem is that your player has been set for a widescreen TV. See 1.22 for details.
Not any time soon. Recordable DVD is for computer data only, not television video (see 1.14). It will take a while before the size of the market drives costs down to VCR levels. However, DVD has many advantages over VCRs, including fundamentally lower technology cost for hardware and disc production (which is appealing to manufacturers), so if DVD is a commercial success it might replace many VCRs in fifteen to twenty years.
Yes. Some CD-ROM drive manufacturers plan to cease CD-ROM drive production after a few years in favor of DVD-ROM drives. Because DVD-ROM drives can read CD-ROMs, there is a compatible forward migration path.
No. DVD uses a smaller wavelength of laser to allow smaller pits in tracks that are closer together. The DVD laser must also focus more tightly and at a different level. In fact, a disc made on a current CD-R writer may not be readable by a DVD-ROM drive (see 2.4.3). It's unlikely there will be "upgrades" to convert CD-R drives to DVD-R, since this would probably cost more than purchasing a new DVD-R drive.
This is actually many questions with many answers:
[Note the differentiation between DVD (general case) and DVD-ROM
(computer data).]
Yes. 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 stated that their DVD hardware will 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.)
Yes. All DVD-ROM drives will read CD-ROMs (Yellow Book). Software on a CD-ROM will run fine in a DVD-ROM system. However, DVD-ROMs are not readable by CD-ROM drives.
Sometimes. The problem is that CD-Rs (Orange Book Part II) are "invisible" to DVD laser wavelength because the dye used in CD-Rs doesn't reflect the beam. Some first-generation DVD-ROM drives and many DVD players can't read CD-Rs. The common solution is to use two lasers at different wavelengths: one for reading DVDs and the other for reading CDs and CD-Rs. Variatons on the theme include Sony's "dual discrete optical pickup" with switchable pickup assemblies with separate optics, Samsung'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 650-nm light, Hitachi's switchable objective lens assembly, and Matsushita's holographic dual-focus lens. Look for drives with the MultiRead label, which guarantees compatibility with CD-R and CD-RW media.
An effort to develop CD-R "Type II" media compatible with both CD and DVD wavelengths has been abandoned.
DVD-ROM drives can't record on any media. Current writable DVD drives (see 4.3) can't record on CD-R, although future versions may be able to.
Usually. CD-Rewritable (Orange Book Part III) has a lower reflectivity difference, requiring new automatic-gain-control (AGC) circuitry. CD-RW discs can't be read by most existing CD-ROM drives and CD players. The new "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 2.4.3).
Current writable DVD drives (see 4.3) can't record on CD-RW, although future versions may be able to.
Sometimes. 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. Panasonic, RCA, Samsung, and Sony models play Video CDs. Japanese Pioneer models play Video CDs but American models older than the DVL-909 don't. Toshiba players older than models 2100, 3107, and 3108 don't play Video CDs.
VCD resolution is 352x288 for PAL and 352x240 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. When playing PAL VCDs, the Panasonic and RCA NTSC players apparently cut 48 lines (17%) off the bottom. The Sony NTSC players apparently scale all 288 lines to fit.
Most DVD-ROM computers can play Video CDs (with the right software), since its already possible with current-model CD-ROM computers.
Note: Many Asian VCDs achieve "two" soundtracks by putting one language on the left channel and another on the right. They will be mixed together into babel on a stereo system unless you adjust the balance to get only one channel.
Not currently. 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 September 1998, winning 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 2.2 Mbps VBR MPEG-2 video (at 480x567 resolution) and 2-channel MPEG-2 Layer II audio. As with DVD, it can overlay graphics for subtitles. Since it's technically easy to make a DVD-Video player compatible with SVCD, it will probably happen soon, but perhaps only on Asian DVD player models. It's not likely that SVCD will be released outside of China and nearby countries.
SVCD players can't play DVDs, since the players are based on CD drives.
Not yet. Since Photo CDs are usually on CD-R media, they may suffer from the CD-R problem (see 2.4.3). That aside, DVD players could support Photo CD with a few extra chips and a license from Kodak. No one has announced such a player. Most DVD-ROM drives will read Photo CDs (if they read CD-Rs) since it's trivial to support the XA and Orange Book multisession standards. The more important question is, "Does the OS or application support Photo CD?" but that's beyond the scope of this FAQ.
In general, no. Most DVD players will not play CD-i (Green Book) discs. However, Philips has announced that it will make a DVD player that supports CD-i. Some people expect Philips to create a "DVD-i" format in attempt to breathe a little more life into CD-i (and recover a bit more of the billion or so dollars they've invested in it).
Yes. DVD players will play music from Enhanced Music CDs (Blue Book, CD Plus, CD Extra), and DVD-ROM drives will play music and read data from Enhanced CDs. Older ECD formats such as mixed mode and track zero (pregap, hidden track) should also be compatible, but there may be a problem with DVD-ROM drivers skipping track zero (as has been the case with some new CD-ROM drivers).
Only the Pioneer DVL-9 player and Pioneer karaoke DVD models DV-K800 and DVK-1000 are known to support CD+G. Most other DVD-V players probably won't support this mostly obsolete format. All DVD-ROM drives support CD+G, but special software is required to make use of it.
Sort of. CDV, sometimes called Video Single, is actually a weird combination of CD and laserdisc. Part 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 system. However, Pioneer and others have announced combination players that will play DVDs, laserdiscs, and CDVs.
No. MP3 is MPEG-1 Layer 3 audio compression. (MP3 is not MPEG-3.) The DVD-Video spec allows Layer 2 only. MP3 can be played on a computer with a DVD-ROM drive, but not in a DVD-Video player.
Yes. Pacific Microsonics' HDCD (high-definition compatible digital) is an encoding process that enhances audio CDs so that they play normally in standard CD and DVD players (and allegedly sound better than normal CDs) yet produce an extra 4 bits of precision (20 bits instead of 16) when played on CD and DVD players equipped with HDCD decoders.
No. Standard DVD players will not play laserdiscs, and you can't play a DVD disc on any standard laserdisc player. (Laserdisc uses analog video, DVD uses digital video; they are very different formats.)
However, Pioneer and Samsung have announced combo players that will play laserdiscs and DVDs (and also CDVs and audio CDs). Denon is rumored to have an LD/DVD player in the works also.
In a way, DVD has already replaced laserdisc, since it's the clear choice for new buyers interested in high-quality video. But laserdisc will still be around for a very long time, since it's well established as a videophile format. There are over 9,000 laserdisc titles in the US and a total of over 35,000 titles worldwide that can be played on over 7 million laserdisc players. It will take DVD several years to reach this point. Until then laserdisc has the superiority of tenure. Pioneer and other laserdisc companies have committed to supporting it (on Sep. 7, 1998, Pioneer's president Kaneo Ito said the company expects laserdisc products to be in the market for another one-and-a-half to two years). There's no reason for laserdisc player owners to stop buying laserdiscs, especially rare titles that may not appear on DVD for a long while if ever. Even laserdisc collectors who buy DVD will not immediately replace their collection. Laserdisc and DVD will co-exist for a long while.
In December of 1996 the FCC approved the U.S. DTV standard. HDTVs became available in late 1998, but they are very expensive and won't become widespread for many years. DVD will look better on HDTVs but it won't provide the highest resolutions. See 2.9 for more information on DVD and HDTV.
The final answer to this question depends on you. If you need to be the first on your block with the latest gadget, you may want to get a DVD player or a combination LD/DVD player now. If you prefer to wait until DVD prices drop and bugs get worked out, you can probably jump in around the end of 1999. If you think DVD isn't a big enough improvement and decide to hold out for HTDV, you'll be in for an even longer wait. In the meantime you could be enjoying the large selection of laserdisc titles. Or you could start saving now for DVD (which isn't too expensive) or HDTV (which is). If you buy a laserdisc player, a surround sound system, and speakers, they will be still be useful even after DVD and HDTV come out. HDTV will require a new TV set, but it will be compatible with the rest of your gear.
Unfortunately, laserdisc was hurt by anticipation of DVD before it even came out. In 1996 laserdisc player sales were down 37% even though sales of VCRs and hi-fi/surround systems were up. The silver lining in this cloud is that disc prices came down. (Laserdisc movie sales were only down 2.5% in 1996.)
Again, it will take years for DVD to reach the number of titles, installed base, and even quality of production that laserdisc has. DVD and laserdisc will coexist for at least another decade. But the potential of DVD can't be ignored -- it's the most likely long-term successor to laserdisc.
For more laserdisc info, see Leopold's FAQ at <http://www.cs.tut.fi/~leopold/Ld/FAQ/index.html>, and Bob Niland's FAQs and overview at <http://www.frii.com/~rjn/laser/> (overview reprinted from Widescreen Review magazine).
It's not likely. DVD circuitry is completely different, the pickup laser is a different wavelength, the tracking control is more precise, etc. No hardware upgrades have been announced, and in any case they would probably be more expensive than buying a DVD player to put next to the laserdisc player.
Short answers: Partially. No.
First, some quick definitions: HDTV (high-definition TV) encompasses both analog and digital televisions that have a 16:9 aspect ratio and approximately 5 times the resolution of standard TV (double vertical, double horizontal, wider aspect). DTV (digital TV) applies to digital broadcasts in general and to the U.S. ASTC standard in specific. The ATSC standard includes both standard-definition (SD) and high-definition (HD) digital formats.
DVD-Video does not directly support HDTV. No digital HDTV standards were finalized when DVD was developed. In order to be compatible with existing televisions, DVD's MPEG-2 video resolutions and frame rates are closely tied to NTSC and PAL/SECAM video formats (see 1.19). DVD does use the same 16:9 aspect ratio of HDTV and the Dolby Digital audio format of U.S. DTV.
HDTV in the US is part of the new ATSC DTV format. The resolution and frame rates of DTV in the US generally correspond to the ATSC recommendations for SD (640x480 and 704x480 at 24p, 30p, 60p, 60i) and HD (1280x720 at 24p, 20p, and 60p; 1920x1080 at 24p, 30p and 60i). (24p means 24 progressive frames/sec, 60i means 60 interlaced frames/sec.) The current DVD-Video spec covers all of SD except 60p. It's expected that future DVD players will output digital video signals from existing discs in SDTV formats. The HD formats are 2.7 and 6 times the resolution of DVD, and the 60p version is twice the frame rate. The ITU-R is working on BT.709 HDTV standards of 1125/60 (1920x1035/30) (same as SMPTE 240M, similar to Japan's analog MUSE HDTV) and 1250/50 (1920x1152/25) which may be used in Europe. The latter is 5.3 times the resolution of DVD's 720x576/25 format. HD maximum data rate is usually 19.4 Mbps, almost twice the maximum DVD-Video data rate. In other words, DVD-Video does not currently support HDTV video content.
HDTV will not make DVD obsolete. Those who postpone purchasing a DVD player because of HDTV are in for a long wait. HDTV became available in late 1998 at very high prices (about $5000 and up). It will take many years before even a small percentage of homes have HDTV sets. CEMA expects 10 percent of U.S. households to have HDTV in 2003, 20 percent by 2005, and 30 percent by 2006.
HTDV sets include analog video connectors (composite, s-video, and component) that will work with all DVD players and other existing video equipment such as VCRs. Existing DVD players and discs will work perfectly with HDTV sets, and will provide a much better picture than any other prerecorded consumer video format, especially once new progressive-scan players become available. Since the cheapest route to HDTV reception will be HDTV converters for existing TV sets, HDTV for many viewers will look no better than DVD.
At some point, HDTV displays will support component digital video connections (YCrCb) and digital data connections (FireWire/IEEE 1394). The digital connections will provide the best possible reproduction of DVD-Video, especially in widescreen mode. Once DVD players have digital outputs, they may be usable as "transports" which output any kind of A/V data (even formats developed after the player was built) to any sort of external display or converter.
The interesting thing many people don't realize is that DTV is happening soonest, fastest, and cheapest on PCs. A year before any consumer DTV sets came out you could buy a DVD PC with a 34" VGA monitor and get gorgeous progressive-scan movies. All for under $3000. The quality of a good DVD PC connected to a data-grade video projector beat