This is the June 16, 2000 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>.
This FAQ is updated at least once a month. If you
are looking at a version more than a month old, it's an out-of-date copy. The
most current version is at DVD
Demystified.
Recent changes (last posted to newsgroups on Feb
9):
-
00-06-16: Note explaining how smart discs check regions. (1.10) Since some people don't believe it's possible.
-
00-06-14: A few new predictions and stats. (1.9)
-
00-06-14: Note about verification slowing write speed in
writable drives. (4.2)
-
00-06-13: New questions:
[0.4] How big is this
thing?
[3.4.1] What does
"lines of resolution" mean?
-
00-06-11: A few corrections and additions to Divx section, plus
a link to the Divx Owners Association. (2.10) Thanks RD.
-
00-06-10: New question: [1.45] What's the
difference between Closed Captions and subtitles?
-
00-06-10: Link to Anthony Haukap's FAQ: How To Adjust a TV. (3.2.2)
-
00-06-10: C3D announces 25GB FMDs that could be readable by new
DVD drives. (2.13)
-
00-06-09: Note about Divx the ripper being different from Divx
the defunct. (2.10 and 4.8)
-
00-06-09: Improved explanation of hooking DVD player to an old
TV with RF modulator. (3.2)
- 00-06-06: DVD-Audio buffer holds more than 16 images. (3.6.1) Thanks Jim.
-
00-05-31: New question: [5.10] Where can I get
DVD training?
-
00-05-22: New section: [5.3.4] Other
production services. (Also revised heading for 5.3 and 5.4.)
-
00-05-22: Links to services for transferring video to DVD. (5.8)
-
00-05-22: Link to multipathmovies.com. (1.42)
-
00-05-21: Link to David Lockwood's explanations of aspect
ratios. (3.5)
-
00-05-21: Official Netherlands FAQ mirror location has changed.
(0)
-
00-05-21: Chinese translation available at dvdfaq.126.com.
-
00-05-15: New questions:
[1.6.1] Where can I
read reviews of DVDs?
[1.6.2] How do I
find out when a movie will be available on DVD?
- 00-05-10: Solution for playing Stuart Little on Apex. (1.41) Thanks Steve.
- 00-05-09: Link to the FlikFX Digital Recomposition System. (1.38)
;-)
- 00-05-09: A bit more on stickers on discs. (1.44) Thanks to thread at rec.video.dvd.misc.
- 00-05-05: Software player for parental management no longer available. (1.42)
- 00-05-01: More about confusing measurements, especially data transfer
rates. (7.2)
- 00-04-20: Freeware MPEG-2 encoder: bbMPEG. (5.3)
- 00-04-20: Clarified issue of streaming CSS movies over a network. (4.7)
- 00-04-20: Super Video CD is an option for creating discs playable on DVD
players. (5.7 and
5.8)
- 00-04-20: Link to Jukka Aho's Super Video CD Overview and FAQ. (2.4.6)
- 00-04-20: 4% speedup of movies on PAL VCDs. (2.4.5)
- 00-04-11: New question: [3.2.2] Why is the
audio or video bad?
- 00-04-10: A little more info on DVD production costs. (5.1)
- 00-03-29: Explanation of various physical and application formats. (1.1)
- 00-03-22: Updated licensing info. (6.1)
- 00-03-19: More details on packaging. (1.17)
- 00-03-19: Major rewrite and simplification of player connection info. (3.1 and 3.2)
- 00-03-16: Cine-bit player for PCs can do parental management for any disc.
(1.42)
- 00-03-16: More coax/optical digital audio converters and VGA-YPrPb
converter. (3.1
and 3.2)
- 00-03-15: Going rate for video to DVD-R transfer: $700/hour. (5.8)
- 00-03-13: Link to 7thZone (replacement for DVDUtils)-- lots of DVD
resources. (6.4)
- 00-03-13: Note that Windows CD-ROM drivers work with DVD-ROM drives. (4.1)
- 00-03-13: Link to TenLab NTSC-PAL converters. (1.19)
- 00-03-13: Link to THX overview. (3.6.2)
- 00-03-08: Info about DVD logo trademark. (6.1)
- 00-03-08: Distortion in Saving Private Ryan is intentional. (1.41)
- 00-03-07: Link to Video CD info at CDPage. (2.4.5)
- 00-03-07: Turns out DeCSS wasn't blocked on recent discs. Info removed.
(4.8)
- 00-03-06: Link to The Digital Bits' Ultimate Guide to Anamorphic
Widescreen. (3.5)
- 00-03-01: Updated info on drive speeds. Table of DVD/CD spins and data
rates. (4.2)
Various translations of the DVD FAQ are available:
If you'd like to translate the DVD FAQ into another language (Klingon,
anyone?), please contact Jim.
Yup. Take a gander at Earl's Famous DVD Technology
Exposition Web Page Extravaganza Supreme Deluxe
<lonestar.texas.net/~bdub/earl/dvd.htm>.
Here are a few user
comments on the DVD FAQ. 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.
Pointers to other DVD sites are scattered throughout the FAQ and in section
6.4.
Since you asked, here are the stats as of June 13, 2000:
Size: 395 KB (405,404 bytes)
Number of words: 49,856
Number of links:
933
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.
DVD, which once stood for Digital Video Disc or Digital Versatile Disc, is
the next generation of optical disc storage technology. It's essentially a
bigger, faster CD that can hold cinema-like video, better-than-CD 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 all major movie and music studios. With this
unprecedented support, DVD has become the most successful consumer electronics
product of all time in less than three years of its introduction.
It's important to understand the difference between the physical
formats (such as DVD-ROM or DVD-R) and the application formats (such
as DVD-Video or DVD-Audio). DVD-ROM is the base format that holds data.
DVD-Video (often simply called DVD) defines how video programs are stored on
disc and played in a DVD-Video player or a DVD computer (see 4.1). The difference is
similar to that between CD-ROM and Audio CD. DVD-ROM includes recordable
variations DVD-R, DVD-RAM, DVD-RW, and DVD+RW (see 4.3). The application
formats include DVD-Video, DVD-Video Recording, DVD-Audio (see 1.23), DVD-Audio
Recording, DVD Stream Recording, and SACD). There are also special application
formats for game consoles such as Sony PlayStation II.
- Over 2 hours of high-quality digital video (over 8 on a double-sided,
dual-layer disc).
- Support for widescreen movies on standard or widescreen TVs (4:3 and 16:9
aspect ratios).
- Up to 8 tracks of digital audio (for multiple languages, DVS, etc.), each
with as many as 8 channels.
- Up to 32 subtitle/karaoke tracks.
- Automatic "seamless" branching of video (for multiple story lines or
ratings on one disc).
- Up to 9 camera angles (different viewpoints can be selected during
playback).
- Menus and simple interactive features (for games, quizzes, etc.).
- Multilingual identifying text for title name, album name, song name, cast,
crew, etc.
- Instant rewind and fast forward (no "be kind, rewind" stickers and threats
on rental discs)
- Instant search to title, chapter, music track, and timecode.
- Durable (no wear from playing, only from physical damage).
- Not susceptible to magnetic fields. Resistant to heat.
- Compact size (easy to handle, store, and ship; players can be portable;
replication is cheaper).
- Noncomedogenic.
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:
- Language choice (for automatic selection of video scenes, audio tracks,
subtitle tracks, and menus).*
- Special effects playback: freeze, step, slow, fast, and scan (no reverse
play or reverse step).
- Parental lock (for denying playback of discs or scenes with objectionable
material).*
- Programmability (playback of selected sections in a desired sequence).
- Random play and repeat play.
- Digital audio output (PCM stereo and Dolby Digital).
- Compatibility with audio CDs.
* Must be supported by additional content on the
disc.
Some players include additional features:
- Component (YUV or RGB) video output for higher-quality picture.
- Progressive-scan component (YUV or RGB) output for highest-quality analog
picture.
- Six-channel analog output from internal audio decoder.
- Recognition and output of DTS Digital Surround audio tracks.
- Compatibility with Video CDs.
- Compatibility with laserdiscs and CDVs.
- Ability to play Divx discs.
- Reverse single frame stepping.
- Reverse play (normal speed).
- RF output (for TVs with no direct video input).
- Multilingual on-screen display.
- Digital zoom (2x or 4x enlargement of a section of the picture). This is a
player feature, not a DVD disc feature.
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 2.8.). However, quality
depends on many production factors. As compression experience and technology
improves we will see increasing quality, but as production costs decrease we
will also see more shoddily produced discs. A few low-budget DVDs will even use
MPEG-1 encoding (which is no better than VHS) instead of higher-quality
MPEG-2.
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 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, improper
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 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 were 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 (or the original
source), not 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.
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.
- It will take years for movies, TV shows, other video programming, and
computer software to become widely available.
- Vagueness of spec and inadequate testing of players and discs has resulted
in incompatibilities. Some movie discs don't function fully (or don't play at
all) on some players.
- It can't record (yet). (See 1.14 and 4.3)
- It has built-in copy protection and regional lockout. (See 1.11 and 1.10)
- It uses digital compression. Poorly compressed audio or video may be
blocky, fuzzy, harsh, or vague. (See 1.3)
- The audio downmix process for stereo/Dolby Surround can reduce dynamic
range. (See 3.6)
- It doesn't fully support HDTV. (See 2.9)
- Some DVD players and drives may not be able to read CD-Rs. (See 2.4.3)
- Current DVD players and drives can't read DVD-RAM discs. (See 4.3)
- Only a few players can play in reverse at normal speed.
- Variations and options such as DVD-Audio, DTS audio tracks, and Divx are
not supported by all players.
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. The first
players appeared in Japan in November, 1996, followed by U.S. players in March,
1997. Players slowly trickled in to other regions. Now, over two years after the
initial launch, over a hundred models of DVD players are available from dozens
of electronics companies. Prices for the first players were $1000 and up. By the
middle of 1999, players were available for under $200 at discount retailers.
See section 6.2
for a list of companies that provide DVD players.
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. The first upgrade kits (combination DVD-ROM drive and
decoder hardware) became available from Creative Labs, Hi-Val, and Diamond
Multimedia in April and May of 1997.
Today, every major PC manufacturer has models that include DVD-ROM drives.
The price difference from the same system with a CD-ROM drive ranges from $30 to
$200 (laptops have more expensive drives). Upgrade kits for older computers are
available for $100 to $700 from Creative
Labs, DynaTek, E4 (Elecede), Hi-Val, Leadtek, Margi Systems (for laptops), Media Forte, Pacific Digital, Sigma Designs, Sony, STB
Systems, Toshiba, Utobia, and others. For more information
about DVDs on computers, including writable DVD drives, see section 4.
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.)
More information:
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 what player is best for
you. Unless you have a high-end home theater setup, a player that costs under
$400 should be completely adequate. Make a list of things that are important to
you (such as ability to play CD-Rs, ability to play Video CDs, 96 kHz/24-bit
audio decoding, DTS Digital Out, internal 6-channel Dolby Digital decoder) to
help you come up with a set of players. 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.
In certain cases, you might want to buy a DVD PC instead of a standard DVD
player, especially if you want progressive video. See 1.40 and 4.1.
Here are a few questions to ask yourself.
- Do I want selectable sound tracks and subtitles, multiangle viewing, aspect
ratio control, parental/multirating features, fast and slow playback, great
digital video, multichannel digital audio, compatibility with Dolby Pro Logic
receivers, on-screen menus, dual-layer playback, and ability to play audio CDs?
If so, this is the wrong question to ask yourself, since all DVD players have
all of these features.
- Do I appreciate special deals? If so, look for free
DVD coupons and free DVD rentals that are available with many players.
- Do I
want DTS audio? If so, look for a player with the "DTS Digital Out" logo. (See
3.6.2.)
-
Do I want to play Video CDs? If so, check the specs for Video CD compatibility.
(See 2.4.5.)
-
Do I need a headphone jack?
- Do I want player setup menus in languages other
than English? If so, look for multilanguage setup feature. (Note: the
multilanguage menus on certain discs are supported by all players.)
- Do I
want to play homemade CD-R audio discs? If so look for the "dual laser" feature.
(See 2.4.3.)
-
Do I want to replace my CD player? If so, you might want a changer that can hold
3, 5, or even hundreds of discs.
- Do I want to control all my entertainment
devices with one remote control? If so, look for a player with a programmable
universal remote, or make sure your existing universal remote is compatible with
the DVD player.
- Do I want to zoom in to check details of the picture? If
so, look for players with picture zoom.
- Do I want to play HDCDs? If so,
check for the HDCD logo. (See 2.4.13.)
- Does
my receiver have only optical or only coax digital audio inputs? If so, make
sure the player has outputs to match. (See 3.2.)
- Do I care
about black-level adjustment?
For more information, read hardware reviews at Web sites such as DVDFile, DVD Resource, and E-Town, or in magazines such as Widescreen
Review. You may also want to read about user experiences in online forums at Home Theater Forum and DVDFile.
See sections 3.1
and 3.2 for specific
information on what audio/video connections are needed to fit into your existing
setup.
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. 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. By
June 1999, over 30 million discs had shipped. As of February 2000 there are just
over 6,000 titles available in the US and over 9,000 worldwide. Compared to
other launches (CD, LD, etc.) this is a huge number in a very short time.
See 6.3 for a
list of Web sites where you can buy or rent DVDs.
Availability of DVD hardware and software in Europe runs about a year to 18
months behind the US. A number of launches were announced with little
follow-through, but DVD began to become established around the end of 1998.
For an extensive, searchable database of movie titles available in the US and
Canada see Doug MacLean's DVD List at <www.hometheaterinfo.com/dvdlist.htm>.
Perry Denton has a text list of region 1 titles at <www.surroundfreak.com/dvd/dvd1.htm>.
For titles in Japan and Europe see Niels van Eijkelenburg's list at <www.surroundfreak.com/dvd/dvd2.htm>
(now out of date). Also check out the Internet Movie Database's DVD Browser or the searchable and
downloadable database from the DVD Entertainment Group. There
are also good searchable databases at DVD
File and Express.com.
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 expected that over 13 percent of all
software would be available in DVD-ROM format by the end of 1998, but reality
didn't meet expectations. 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.
The following sites have reviews of at least 400 discs. Also see the list of
DVD review
sites at Yahoo.
First, check one of the lists and databases mentioned in 1.6 to make sure it's
not already available. Then check the upcoming release lists at DVD Review and Laser Scans. There's also the
LaserViews DVD
Calendar and release list at Image Entertainment. A good
source of info about unannounced titles is The Digital Bits Rumor Mill.
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 some early predictions, but faster than videotape, laserdisc,
and CD. Before it's third birthday in March 2000, DVD had become the most
successful consumer electronics product ever.
Here are some predictions:
- Toshiba (1996): 100,000 to 150,000 DVD-Video players will be sold in Japan
between Nov. 1 and Dec. 31, 1996, and 750,000-1 million by Nov. 1, 1997.
(Actual count of combined shipments by Matsushita, Pioneer, and Toshiba was
70,000 in Oct-Dec 1996.)
- Pioneer (1996): 400,000 DVD-Video players in 1996, 11 million by 2000.
100,000 DVD-Audio players in 1996, 4 million by 2000.
- InfoTech (1996): 820,000 DVD-Video players in first year, 80 million by
2005.
- CEMA (1997): 400,000 DVD-Video players in U.S. in 1997, 1 million in 1998.
- Time-Warner (1996): 10 million DVD players in the U.S. by 2002.
- Paul Kagan (1997): 800,000 DVD players in the U.S. in 1997, 10 million in
2000, and 40 million in 2006 (43% penetration). 5.6 million discs sold in
1997, 172 million discs in 2000, and 623 million in 2006.
- C-Cube (1996): 1 million players and drives in 1997.
- BASES: 3 million DVD-Video players sold in first year, 13 million sold in
6th year.
- Dataquest (1997): over 33 million shipments of DVD players and drives by
2000.
- Philips (1996): 25 million DVD-ROM drives worldwide by 2000 (10% of
projected 250 million optical drives).
- Pioneer (1996): 500,000 DVD-ROM drives sold in 1997, 54 million sold in
2000.
- Toshiba (1996): 120 million DVD-ROM drives in 2000 (80% penetration of 100
million PCs). Toshiba says they will no longer make CD-ROM drives in 2000.
- IDC (1997): 10 million DVD-ROM drives sold in 1997, 70 million sold in
2000 (surpassing CD-ROM), 118 million sold in 2001. Over 13% of all software
available on DVD-ROM in 1998. DVD recordable drives more than 90% of combined
CD/DVD recordable market in 2001.
- AMI (1997): installed base of 7 million DVD-ROM drives by 2000.
- Intel (1997): 70 million DVD-ROM drives by 1999 (sales will surpass CD-ROM
drives in 1998).
- SMD (1997): 100 million DVD-ROM/RAM drives shipped in 2000.
- Microsoft (Peter Biddle, 1997): 15 million DVD PCs sold in 1998, 50
million DVD PCs sold in 1999.
- Microsoft (Jim Taylor, 1998): installed base of 35 million DVD PCs in
1999.
- Forrester Research (1997): U.S. base of 53 million DVD-equipped PCs by
2002. 5.2% of U.S. households (5 million) will have a DVD-V player in 2002; 2%
will have a DVD-Audio player.
- Yankee Group (Jan 1998): 650,000 DVD-Video players by 1998, 3.6 million by
2001. 19 million DVD-PCs by 2001.
- InfoTech (Jan 1998): 20 million DVD-Video players worldwide in 2002, 58
million by 2005. 99 million DVD-ROM drives worldwide in 2005. No more than 500
DVD-ROM titles available by the end of 1998. About 80,000 DVD-ROM titles
available by 2005.
- Screen Digest (Dec 1998): 125,000 DVD-Video player in European homes in
1998, 485,000 in 1999, 1 million in 2000.
- IRMA (Apr 2000): 12 million players will ship worldwide in 2000.
- Baskerville (Apr 2000): Worldwide spending on DVD software will surpass
that of VHS by 2003. There will be a worldwide installed based of 625 million
DVD players by 2010 (55% of TV households).
- Jon Peddie (Jun 2000): Almost 20 million DVD players will be sold in the
U.S. in 2004.
Here's reality:
- 1997
- 349,000 DVD-Video players shipped in the U.S. (About 200,000 sold into
homes.)
- 900 DVD-Video titles available in the U.S. Over 5 million copies
shipped; about 2 million sold.
- Over 500,000 DVD-Video players shipped worldwide.
- Around 330,000 DVD-ROM drives shipped worldwide with about 1 million
bundled DVD-ROM titles.
- 60 DVD-ROM titles (mostly bundled).
- 1998
- 1,089,000 DVD-Video players shipped in the U.S. (Installed base of
1,438,000.)
- 400 DVD-Video titles in Europe (135 movie and music titles).
- 3,000 DVD-Video titles in the U.S. (2000 movie and music titles).
- 7.2 million DVD-Video discs purchased.
- 1999
- 4,019,000 DVD-Video players shipped in the U.S. (Installed base of
5,457,000.)
- Over 6,300 DVD-Video titles in the U.S.
- About 26 million DVD-ROM drives worldwide.
- About 75 DVD-ROM titles available in the U.S.
- 2000 (as of June)
- Over 2 million DVD-Video players shipped in the U.S. (Installed base of
7,470,000.)
- About 34 million DVD-ROM drives worldwide.
- Over 9,000 DVD-Video titles available in the U.S.
(For latest U.S. player sales statistics, see the CEA page at
The Digital Bits.)
For comparison, there were 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 were 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 270 million TVs in the U.S. and 1.3 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. Some people believe that region codes could be
considered an illegal restraint of trade, but there have been no legal cases to
establish this.
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 8 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: U.S., Canada,
U.S. Territories
2: 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 Union), Indian subcontinent,
Africa, North Korea, and Mongolia
6: China
7: Reserved
8: Special
international venues (airplanes, cruise ships, etc.)
(See the map at <www.unik.no/~robert/hifi/dvd/world.html>.)
There is no such thing as a region 0 disc. There is such thing as an
all-region disc. There are region 0 players (see next paragraph).
Some players can be modified to play discs regardless of their regional
codes. This usually voids the warranty, but is probably not illegal. (The only
thing that requires player manufacturers to make region-coded players is the CSS
license. See 1.11)
Some discs from Fox, Buena Vista/Touchstone/Miramax, MGM/Universal, and Polygram
contain program code that checks for the proper region. (There's Something
About Mary is a recent example.) These "smart discs" that do active region
checking won't play on code-free players that have their region set to 0,
but they can be played on manual code-switchable players that allow you
to change the region using the remote control. 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. A disc can have all its
region flags set so that the player doesn't know which one to switch to, then it
can query the player for the region setting and abort if it's the wrong one. A
default setting of region 1 will fool smart discs from region 1.) Information
about modifying players can be found on the Internet (at sites such as Code Free DVD, dvdkits.com, DVD Upgrades, Link Electronics, PlanetDVD, 7thZone, Techtronics, Upgrade Heaven, and <www.brouhaha.com/~eric/video/dvd/>)
and in the rec.video.dvd newsgroups (searchable at Deja.com).
Regional codes also apply to DVD-ROM systems, but used 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 changes) it
can't be changed again unless the vendor or manufacturer resets it. The Drive
Info utility can tell you if you have an RPC2 drive (it will say "This drive has
region protection"). Drive Info and information about circumventing DVD-ROM
region restrictions is available from Internet sites such as Visual Domain and DVD Infomatrix. After December 31, 1999,
only RPC Phase II drives will be manufactured.
Regional codes do 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 problems for many
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" 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 once 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 (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
<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 standard. Content Scrambling System
(CSS) is a data encryption and authentication scheme intended to prevent copying
video files directly from the disc. CSS was developed primarily by Matsushita
and Toshiba. Each CSS licensee is given a key from a master set of 400 keys that
are stored on every CSS-encrypted disc. This allows 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. On the computer side, 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.
Beginning in 2000, new DVD-ROM drives are required to support regional
management in conjunction with CSS (see 1.10 and 4.1). Makers of
equipment used to display DVD-Video (drives, decoder chips, decoder software,
display adapters, etc.) must license CSS. There is no charge for a CSS license,
but it's 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. 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
October 1999, the CSS algorithm was cracked and posted on the Internet,
triggering endless controversies and legal battles (see 4.8).
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. Sony released a
DTCP chip in mid 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 until 2000. Since the encryption is
done by the player, no changes are needed to the existing disc format.
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 Macrovision, although only a few work
with the new Colorstripe feature. These devices go under names such as Video
Clarifier, Image Stabilizer, Color Corrector, and CopyMaster.
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 1996) and the compliant U.S. Digital Millennium Copyright Act (DMCA), passed
into law in October 1998. Software intended specifically to circumvent copy
protection is now illegal in the U.S. and many other countries. 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." It's not at
all clear how this might be "permitted" by a player or by studios that set the
"don't copy" flag on 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
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. See 4.1
for more information on DVD-ROM drives.
The Watermarking Review Panel (WaRP) --the successor to 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. The second group has dubbed their technology "Millennium."
Watermarking, which is used for DVD-Audio and will be added to DVD-Video at some
point, permanently marks each digital audio or video frame with noise that is
supposedly undetectable by human ears or eyes. 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. 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 were reports that the early watermarking technique
used by Divx caused visible "raindrop" or "gunshot" patterns, but the problem
seemed to have been solved for later releases.
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 (minus copy protection) was approved in February 1999 and released
in March, but products were delayed in part by the slow process of selecting
copy protection features (encryption and watermarking), with complications
introduced by the Secure Digital Music Initiative (SDMI). The scheduled October
1999 release was further delayed until mid 2000, ostensibly because of concerns
caused by the CSS crack (see 4.8), but also because
the hardware wasn't quite ready, production tools aren't up to snuff, and there
is lackluster support from music labels. Pioneer released DVD-Audio players in
Japan in late 1999, but they won't play copy-protected discs.
Matsushita hopes to have Panasonic and Technics brand universal
DVD-Audio/DVD-Video players available in July 2000 for $700 to $1,200. Pioneer,
JVC, Yamaha, and others may also release DVD-Audio players at the same time.
However, there seem to be almost no DVD-Audio titles to play on the new
players.
In the meantime, the DVD-Video standard includes surround sound audio and
better-than-CD audio (see 3.6.2).
DVD-Audio is a separate format from DVD-Video. DVD-Audio discs can be
designed to work in DVD-Video players, but it's 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 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,
multichannel 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 only 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 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. Audiophiles claim this degrades the audio, but tests
performed by the 4C indicate that even golden-eared listeners can't detect the
watermarking noise. Proposals from Aris, Blue Spike, Cognicity, IBM, and Solana
were evaluated by major music companies in conjunction with the 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 1999. (In November 1999, Verance watermarking was also
selected for SDMI.)
Sony and Philips have developed a competing Super Audio CD format that uses
DVD discs. (See 3.6.1 for details.)
SACD is supposed to provide "legacy" discs that have two layers, one that plays
in existing CD players, plus a high-density layer for DVD-Audio players, but
technical difficulties have kept dual-format discs from being produced.
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 appeared in April (?) 1999. SACD technology is
available to existing Sony/Philips CD licensees at no additional
cost. Pioneer, which released the first DVD-Audio players in Japan at the
end of 1999, included SACD support in their DVD-Audio players. If other
manufacturers follow suit, the entire SACD vs. DVD-Audio standards debate will
be moot, since DVD-Audio players will play both types of discs.
Sony released an SACD player in Japan in May 1999 at the tear-inducing price
of $5,000. The player was released in limited quantities in the U.S. at the end
of 1999. New lower cost SACD players will be available by fall 2000. Initial
SACD releases are mixed in stereo, not multichannel. About 40 SACD titles were
available at the end of 1999, from studios such as DMP, Mobile Fidelity Labs,
Pioneer, Sony, and Telarc.
All major movie studios, most major music studios.
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 publishers. 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: Not yet, but soon. Most of the major DVD player manufactureres
have announced DVD home video recorders. (See 4.3.)
Long answer: Recording analog video to DVD is a very tricky process. 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. It's difficult in real time to encode the video
and audio, combine them with DVD-Video info, and write the whole thing to a
recordable DVD disc, especially in a form that's compatible with standard
DVD-Video players. This is still extremely expensive for a home recorder, even
though prices for DVD production systems have dropped over the space of three
years from millions of dollars to thousands of dollars to hundreds of dollars
for the simplest packages.
Other obstacles: Blank discs cost about $25 (although they will get cheaper
over time). Real-time compression requires higher bit rates for decent quality,
thus lowering capacity. 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 special prefilters, which increases the cost).
Don't be confused by DVD-R drives, DVD-RAM drives, or other recordable DVD
drives for computers (see 4.3). These existing
recorders can store 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.
In spite of all the difficulties, many of the major DVD manufacturers are
working on recordable DVD for the home. We will see various DVD video recorders
in the year 2000. Early units, especially those that can record from analog
video sources such as TV, will be expensive: probably $2,000 and up. There will
also be cheaper units that can record only from a source of already-compressed
digital audio and video, such as satellite, DTV, or digital cable. At some
point, DVD recorder/players will be built into satellite and cable
receivers.
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. Once the encoding
technology is fast and cheap enough, and blank discs are cheap enough,
recordable DVD will reach the mainstream.
Most scratches will cause minor channel data errors that are easily
corrected. That is, data is stored on DVDs using powerful error correction
techniques that can recover from scratches as big as 6 millimeters 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!) 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 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. Major scratches may cause uncorrectable errors that will
produce an I/O error on a computer or show up as a momentary glitch in DVD-Video
picture. 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.
See 1.39 for
information on care and cleaning of DVDs.
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 <home.earthlink.net/~tlfordham/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 that are as wide as a CD jewel box (about 5-5/8") and as tall as a
VHS cassette box (about 7-3/8"), as recommended by the Video Software Dealers
Association (VSDA). 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 inserts, 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, for over 4 hours of video (see 3.3 for more details).
Many discs use dual layers. Initially only a few replication plants 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), 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 is designed to provide continuous
video across both layers. 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 up to 4
seconds on other players. 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 long movies can
use higher data rates for better quality than with a single layer. See 1.27 for layer change
details.
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.
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 2.12 for note
on reading both sides simultaneously.)
DVD 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 encoded 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 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 for SECAM TVs.
Some players only play NTSC discs, some players only play PAL discs, and some
play both. All DVD players sold in PAL countries play both. These
multi-standard players partially convert NTSC to a 60Hz PAL (4.43 NTSC)
signal. The player uses the PAL 4.43 MHz color subcarrier encoding format but
keeps the 525/60 NTSC scanning rate. Most modern PAL TVs can handle this kind of
"pseudo-PAL" 60-Hz signal. A few multi-standard PAL players output true 3.58
NTSC from 525/60 NTSC discs, which requires an NTSC TV or a multi-standard TV.
Some players have a switch to choose 60-Hz PAL or NTSC output when playing NTSC
discs. There are a few standards-converting PAL players (from Samsung and
others) that convert from a 525/60 NTSC disc to standard PAL output. Proper
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 60Hz PAL output with a compatible TV provides a better
picture. Most NTSC players can't play PAL discs. A very small number of NTSC
players (such as the Apex) can convert 625/50 PAL to NTSC. External converter
boxes are also available, such as the Emerson EVC1595 ($350). High-quality
converters are available at TenLab.
A producer can choose 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 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 from a single side, 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 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 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.
There is a list of "flipper" discs in the Film Vault at DVD
Review. Note: A flipper is not the same as a disc with a widescreen version on
one side and a pan & scan version or supplements on the other. Please send
additions to info@dvdreview.com. (The
list has gotten too long to keep in this FAQ.)
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 or other chemical change. This often
results from the use of insufficiently pure aluminum 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). Deterioration of the data layer can
be caused by chemical contaminants or gasses in the glue, or by moisture that
penetrates the acrylic substrates.
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.
It's too early to know for sure, but DVDs will probably have few laser rot
problems. There have been reports of a few discs going bad, possibly due to poor
adhesive, chemical reactions, or oxidation of the aluminum layer. See www.mindspring.com/~yerington/.
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 Film Vault at DVD
Review, or from Internet
Movie Database (which also includes discs with both widescreen and pan &
scan versions).
On the remote control, press Subtitle, then either Clear or 0 (zero). No need
to use the menus.
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. 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.
There is a list of layer switch points in the Film Vault at DVD
Review. Please send new times to info@dvdreview.com. (The list has gotten
too long to keep in this FAQ.)
Some discs (many from Columbia TriStar) have 2-channel Dolby Surround audio
(or plain stereo) on track one and 5.1-channel audio on track two. Since 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 5.1-channel track (with the audio button on
the remote or with the on-screen menu) the player will play the default
2-channel track. (Note: Some players such as the Sony 3000 have 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,"
and so on refer both to DVD-Video players and to DVD-ROM drives. 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 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 2.12) 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 or fourth
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.
Some people refer to RPC2 drives or 10x drives as fourth generation. See section
4.2 for more speed
info. See section 1.10 for RPC2
explanation.
Do you really want the answer to this one? Ok, you asked for it...
- A disc that works in both DVD-Video players and DVD-ROM PCs. (The most
common use of the term hybrid, but more accurately called an enhanced
DVD)
- A DVD-ROM disc that runs on Windows and Mac OS computers. (More accurately
called a cross-platform DVD.)
- A DVD-ROM or DVD-Video disc that also contains Web content for connecting
to the Internet. (More accurately called a WebDVD or
Web-connected DVD.)
- A disc that contains both DVD-Video and DVD-Audio content. (More
accurately called a universal DVD.)
- A disc with two layers, one that can be read in DVD players and one that
can be read in CD players. (More accurately called a legacy or
CD-compatible disc.) There are at least three variations of this hybrid
(none were commercially available as of 12/99):
- A 1.2mm CD substrate bonded to the back of a 0.6mm DVD substrate. One
side can be read by CD players, the other side by DVD players. The resulting
disc is 0.6mm thicker than a standard CD or DVD, which can cause problems in
players with tight tolerances, such as portables. Sonopress, the first
company to announce this type, calls it DVDPlus. It's colloquially known as
a "fat" disc.
- A 0.6mm CD substrate bonded to the front of a semitransparent 0.6mm DVD
substrate. Both layers are read from the same side, with the CD player being
required to read through the semitransparent DVD layer, causing problems
with some CD players.
- A 0.6mm CD substrate, with a special refractive coating that causes a
1.2mm focal depth, bonded to the back of a 0.6mm DVD substrate. One side can
be read by CD players, the other side by DVD players.
- A disc with two layers, one containing pressed (DVD-ROM) data and one
containing rewritable (DVD-RAM, etc.) media for recording and re-recording.
(More accurately called a mixed-media or rewritable sandwich
disc.)
- A disc with two layers on one side and one layer on the other. (More
accurately called a DVD-14.)
- A disc with an embedded memory chip for storing custom usage data and
access codes. (More accurately called a chipped DVD.)
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 meaningfully
perceptible difference. 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 1999 DTS encoders
are available for purchase. DTS titles are generally considered to be specialty
items intended for audio enthusiasts. It's expected that most DTS will also be
available in a Dolby Digital-only version.
DTS is an optional format on DVD. Contrary to what some people claim, the DVD
specification has included an ID code for DTS since 1996 (before the spec was
even finalized). Because DTS was slow in releasing encoders and test discs,
players made before mid 1998 (and many since) ignore DTS tracks. A few demo
discs were created in 1997 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 proper DTS audio stream ID 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 appear in November 1998. DTS-compatible players 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 of a full-length movie, essentially every disc with a DTS soundtrack
also carries 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 work on all DVD players, since the DTS
data is encapsulated into standard PCM tracks that are passed untouched to the
digital audio output.
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 on-screen
setting to select the output format for NTSC discs, choosing PAL (60-Hz) may
solve the problem. See section 1.19 for more
information.
Or you may have connected one of the component outputs (Y, R-Y, or B-Y) of
your DVD player to the composite input of your TV. See section 3.2 for hookup
details.
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.
There have been numerous reports of "lip sync" problems, where the audio lags
slightly behind the video, and even reports of the audio coming before the
video. Perception of a sync problem is highly subjective--some people are
bothered by it while others can't discern it at all. Problems have been reported
on a variety of players (notably the Pioneer 414 and 717 models, possibly all
Pioneer models, some Sony models including the 500 series, new Toshiba models
including the 3109, and 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).
The cause of the sync problem is a complex interaction of as many as four
factors
- Improper sync in audio/video encoding or DVD-Video formatting.
- Poor sync during film production or editing (especially post-dubbing or
looping).
- Loose sync tolerances in the player.
- Delay in the external decoder/receiver.
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. Pioneer has stated
that altering the audio-visual synchronization of their players "to compensate
for the software quality would dramatically compromise the picture
performance."
Unfortunately, there is no simple answer and no simple fix. More complaints
from customers will motivate manufacturers to take the problem more seriously
and hopefully correct it in future players or with firmware upgrades.
You are seeing the effects of Macrovision copy protection (see 1.11), probably
because you are running your DVD player through your VCR or VCR/TV combo (see 3.2.1).
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 3.5), and in many cases
you can't get rid of them. If you set the display option in your player to pan
& scan (sometimes called fullscreen or 4:3) instead of letterbox, it won't
do you much good since no DVD movies have been released with this feature
enabled.
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):
- Check the other side of the disc (if it's two-sided)
- Look for a fullscreen choice in the main menu
- Use the "aspect" button on the remote control
DVD was designed to make movies look as good as possible on TV. Since most
movies are wider than most TVs, letterboxing preserves the format of the
theatrical presentation. (Nobody complains that the top and bottom of the
picture are cut off in theaters.) DVD is ready for TVs of 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 1.85 ("flat") aspect
ratio or less. In this case, the actual size of the images on your TV are the
same for a letterbox version and a full-frame version, unless the pan & scan
technique is used to zoom in (which cuts off part of the picture). In other
words, the picture is the same size, with extra stuff visible at the 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 1.85,
in which case the letterboxed picture is smaller and has less detail than a pan
& scan version would.
For a detailed explanation of why most movie fans prefer letterboxing, see
the Widescreen
Cinema page and the Letterbox/Widescreen Advocacy Page. For an
explanation of anamorphic widescreen and links to more information on other Web
sites, see 3.5. For
an anti-letterboxing viewpoint, see the FAQ About Letterboxing
(Letterschlocking), after which you might want to read a rebuttal
page.
The best solution to this entire mess is the FlikFX Digital Recomposition
System, "the greatest advance in entertainment in 57 years."
Since DVDs are read by a laser, they are resistant—to a point—to
fingerprints, dust, smudges, and scratches (see 1.15 for more info).
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 there are
globs of nasty substances on it that might actually hit the lens. Still, it's
best to keep your discs clean, which will also keep the inside of your player
clean. Never attempt to play a cracked disc, as it could shatter and damage the
player. It probably doesn't hurt to leave the disc in the player (even if it's
paused and still spinning), but leaving it running unattended for long periods
of time is not advisable.
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 commonly use a lens
cleaning disc in your CD player, you may want to do the same with your DVD
player. I recommend only using a cleaning disc designed for DVD players, since
there are minor differences in lens positioning.
There is no need for periodic alignment of the pickup head. Sometimes the
laser can drift out of alignment, especially after rough handling of the player,
but this is not a regular maintenance item.
Care and feeding of DVDs
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. Do not 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.
Make certain the disc is properly seated in the player tray before you close
it.
Keep away from radiators/heaters, hot equipment surfaces, direct sunlight
(near a window or in a car during hot weather), pets, small children, and other
destructive forces. Magnetic fields have no effect on DVDs.
Coloring the outside edge of a DVD with a green marker makes no difference in
video or audio quality. Data is read based on pit interference at 1/4 of the
laser wavelength, a distance of less than 165 nanometers. A bit of dye that on
average is more than 3 million times farther away is not going to affect
anything.
Cleaning and repairing DVDs
If you notice problems when playing a disc, you may be able to correct them
with a simple cleaning.
- Do not use strong cleaners, abrasives, solvents, or acids.
- With a soft, lint-free cloth, wipe gently in only a radial direction (a
straight line between the hub and the rim). Since the data is arranged
circularly on the disc, the micro scratches you create when cleaning the disc
(or the nasty gouge you make with the dirt you didn't see on your cleaning
cloth) will cross more error correction blocks and be less likely to cause
unrecoverable errors).
- Don't use canned or compressed air, which can be very cold and may
thermally stress the disc.
- For stubborn dirt or gummy adhesive, use water, water with mild soap, or
isopropyl alcohol. As a last resort, try peanut oil. Let it sit for about a
minute before wiping it off.
- There are commercial products that clean discs and provide some protection
from dust, fingerprints, and scratches. Cleaning products labeled for use on
CDs work as well as those that say they are for DVDs.
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 ECC block. Examine the disc,
keeping in mind that the laser reads from the bottom. There are essentially two
methods of repairing scratches: 1) fill or coat the scratch with an optical
material; 2) polish down the scratch. There are many commercial products that do
one or both of these, or you may wish to buy polishing compounds or toothpaste
and do it yourself. The trick is to polish out the scratch without causing new
ones. A mess of small polishing scratches can 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 discs may
want to invest in a commercial polishing machine that can restore a 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 re-polished
about half as many times.
A progressive-scan DVD player converts the interlaced (480i) video from DVD
into progressive (480p) format for connection to a progressive display (31.5 kHz
or higher). (See 3.8
for an explanation of interlaced and progressive scanning.) Progressive players
work with all standard DVD titles, but look best with film source. The result is
a significant increase in perceivable vertical resolution, for a more detailed
and film-like picture.
Toshiba developed the first progressive-scan player (SD5109, $800) in mid
1998, but didn't release it until fall of 1999 because of copy protection
concerns. Panasonic also released a progressive-scan player (DVD-H1000, $3000)
at about the same time. At the January 2000 CES show, most DVD player
manufacturers talked about upcoming progressive players. It's also possible to
buy an external line multiplier, such as the DVDO, to convert the output of a standard DVD
player to progressive scanning. All DVD computers are progressive players, since
the video is displayed on a progressive monitor, but quality varies a lot. (See
4.1 and 2.12.)
Converting interlaced DVD video to progressive video involves much more than
putting film frames back together. There are essentially two ways to convert
from interlaced to progressive:
1- Re-interleaving (also called
weave). If the original video is from a progressive source, such as film,
the two fields can be recombined into a single frame.
2- Line doubling
(also called bob). If the original video is from an interlaced source,
simply combining two fields will cause motion artifacts (the effect is
reminiscent of a zipper), so 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.
(3- There's actually
a third way, called field-adaptive de-interlacing, which examines
individual pixels across three or more fields and selectively weaves or bobs
regions of the picture as appropriate. Most systems that do this well cost
$10,000 and up, so it will be a while before we see it in consumer DVD
players.)
(4- And there's also a fourth way, called motion-adaptive
de-interlacing, which examines MPEG-2 motion vectors or does massive image
processing to identify moving objects in order to selectively weave or bob
regions of the picture as appropriate. Most systems that do this well cost
$50,000 and up (aside from the cool but defunct Chromatic Mpact2 chip).
There are three common kinds of de-interlacing systems:
1-
Integrated. This is usually best, where the de-interlacer 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.
2- Internal. 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 are no longer available to help the de-interlacer determine
the original format and cadence. (Some internal chips use the repeat_first_field
and top_field_first flags passed from the decoder, but not the progressive_scan
flag.)
3- External. Analog video from the DVD player is passed to a
separate line doubler or to a display with a built-in line doubler. 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 bobs, weaves, and
interpolates to a variety of scanning rates) may achieve the best results.
(Note: from what I've been able to gather, the Panasonic DVD-H1000 and the
Toshiba models (SD5109, SD9100, SD6200, SD9200) all use an internal Genesis
gmVLX1A de-interlacing chip. The Princeton PVD-5000 uses a Sigma Designs decoder
with integrated de-interlacing. Toshiba's "Super Digital Progressive" players
and the Panasonic HD-1000 use 4:4:4 chroma oversampling, which provides a slight
quality boost from DVD's native 4:2:0 format.)
A progressive DVD player has to determine whether the video should be
line-doubled or re-interleaved. When re-interleaving film-source video, the
player also has to deal with the difference between film frame rate (24 Hz) and
TV frame rate (30 Hz). Since the 2-3 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 resolution more than
makes up for it. Advanced progressive players such as the Princeton PVD-5000 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, or when the video
is speed-shifted to match the audio track). Another problem is that many DVDs
are encoded with incorrect MPEG-2 flags, so the re-interleaver has to recognize
and deal with pathological cases. In some instances it's practically impossible
to determine if a sequence is 30-frame interlaced video or 30-frame progressive
video. For example, the documentary on Apollo 13 is interlaced video
encoded as if it were progressive. Other cases of improper encoding are
Fargo and More Tales of the City.
A growing problem is that many TVs with progressive input don't allow the
aspect ratio to be changed. When a non-anamorphic signal is sent to these TVs,
they stretch it out! Before you buy an HDTV, make sure that it allows aspect
ratio adjustment on progressive input.
Just as early DVD computers did a poor job of progressive-scan display of
DVDs, the first generation 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.
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 here and there. The DVD-Video standard has not changed
substantially since it was finalized in 1996, but 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. A few discs have problems or
wont play at all in certain players. In some cases, manufacturers can fix the
problem with an upgrade to the player (check with tech support). In other cases,
disc producers need to re-author the title to correct an authoring problem or to
work around a player defect.
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.
| Title |
Player |
Problem |
Solution |
| various Polygram titles |
early Toshiba and Magnavox models |
won't load or freezes |
upgrade available from Toshiba service centers |
| various Central Park Media (anime) titles |
similar problems as The Matrix |
| The Abyss, disc 2 |
early Toshiba models |
won't load or freezes |
upgrade available from Toshiba service centers |
| American Pie |
Philips 940 |
freezes at layer change (1:17:09) |
|
| Arlington Road |
see Cruel Intentions |
| Armageddon |
Panasonic A115-U and A120-U |
won't load |
unplug player with disc inserted, plug in, turn on |
| Avenger's TV series (A&E) |
Toshiba SD-3108 |
locks up player |
upgrade available from Toshiba service centers |
| Philips 930, 935 |
won't load |
check with Philips for firmware upgrade |
| Cruel Intentions |
some JVC and Yamaha |
error in first release messes up parental controls, causing other
discs to not play |
reset the
player or get the corrected version of the disc or set parental
country code to AD with password of 8888 |
| Deep Blue Sea |
similar problems as The Matrix |
| Dragon's Lair |
Toshiba SD-2109/3109 |
various |
upgrade available from Toshiba service centers |
| most Samsung, Aiwa |
various |
check with Samsung (800-726-7864) or Aiwa for firmware upgrade |
| Entrapment |
JVC |
freezes |
check with JVC for firmware
upgrade |
| Sigma Hollywood Plus |
see The World Is Not Enough |
| Space Ace |
see Dragon's Lair |
| The Last Broadcast |
GE 1105P |
won't load |
|
| The Last Of the Mohicans |
see The World Is Not Enough |
| Lost In Space |
Sharp |
freezes |
|
| Creative DXR3 |
freezes, audio out of sync |
check for updated
drivers |
| The Man With The Golden Gun |
a few first-generation players, many software player |
garbled video after layer change |
might be a disc authoring error |
| The Matrix |
various players |
various problems |
details at PCFriendly
tech support
(for GE 1105-P, serial number beginning
with 940 or lower, get upgrade from GE) |
| The Mummy |
Philips 930, 935 |
won't load |
|
| Idle Hands |
see Cruel Intentions |
| Saving Private Ryan |
all players |
distortion (smearing, flares) in beach scene at end of ch. 4 |
This is a deliberate camera effect in the film. Stop returning
discs. |
| The Sixth Sense |
Sigma Hollywood Plus |
MMSYSTEM275 error |
wait for a software update from Sigma |
| Space Ace |
Toshiba 2109, 3109 (before mid 1999) |
doesn't play correctly |
firmware update available from Toshiba |
| Stargate SE |
Magnavox 400AT |
freezes in director's commentary |
|
| Stargate SE |
Magnavox 400AT |
freezes in director's commentary |
|
| Stuart Little |
Apex AD-600A |
won't play past menu |
press Resume on remote control |
| The World is Not Enough |
Sigma Hollywood Plus |
MMSYSTEM275 error |
Wait for a software update from Sigma. Might be related to trying to
play in wrong region. |
| Tomorrow Never Dies |
Sharp 600U
Bush DVD2000 |
locks up player
won't load |
|
| Universal Soldier |
Wharfedale 750 |
picture breakup after ch. 30 |
might be a problem with the disc |
| Wild Wild West |
Samsung DVD 709; Philips 930, 935; GE 1105P |
won't load |
check with Samsung (800-726-7864), Philips, or GE for firmware
upgrade |
| You've Got Mail |
various players |
various problems |
details at PCFriendly
tech support |
For other DVD and home theater problems, try Ask Digital Man, Doc DVD, or DVD Digest's
Tech Support Zone. For
troubleshooting DVD on computers, see 4.6. The Dell Inspiron 7000 DVD Movie
List has Inspiron-specific problems.
DVD includes parental management features for blocking playback and for
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 File, and there's a
Studio and Manufacturer Feedback area at Home Theater Forum.
Multi-ratings discs include Kalifornia, Crash, Damage, Embrace
of the Vampire, Poison Ivy, Species II. 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 (2000 release). Also see http://www.multipathmovies.com/.
Another option is to use a software player on a computer that can
read a "play list" telling it where to skip scenes or mute the audio. Play lists
can be created for the thousands of DVD movies that have been produced without
parental control features. There was a shareware Cine-bit DVD Player that did this, but it has
apparently been withdrawn because of legal threats from Nissim, who seem determined to stifle the very
market they claim to support. A few other projects are under development.
Yet another option is TVGuardian or
Curse Free TV, a 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.)
There's actually a euphemism in the DVD industry, where "multi-angle titles"
--spoken with the right inflection-- means adult titles. However, apart from
hundreds of X-rated discs, not very many 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. 1 was one of the first to use camera angles, in the
animated "Big Story," which is also available on the DVD Demystified sample disc. Ultimate
DVD (Gold or Platinum) is another sample disc with examples of angles. King
Crimson: 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 video),
Ghostbusters 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 button locked out).
You can get an incomplete list of multi-angle discs by doing an extended search
at DVD File or a power search at
DVD Express. To weed out the adult titles at DVD Express, select all entries in
the category list (click top entry, Shift-click bottom entry) then deselect
Adult (Ctrl-click).
Libraries and DVD rental outlets often want to label discs or attach magnetic
strips for security. Rectangular labels and strips are a bad idea since they can
unbalance the disc and cause errors, or even damage a player, especially if they
peel off while the disc is spinning. It's best not to use stickers at all, but
if you must, use a ring-shaped label that goes around the center of the disc. As
long as the label doesn't interfere with the player clamping onto the hub, it
should be fine. If you have to use a non-circular label, place it as close to
the center as possible to minimize unbalancing. Placing a second label straight
across from the center will also help.
In most cases a better alternative is a security 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.
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 1993
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 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 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 3.4 for technical
details). 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 still 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.
See A Guide to DVD
Subtitles and Captioning and the Caption FAQ for more about
Closed Captions. Note that DVD does not support PAL Teletext, the much-improved
European equivalent of Closed Captions.
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, covered in the following
sections.
[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.) 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.)
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
formulation of dye used by different CD-R manufacturers also affects
readability. The common solution is to use two lasers at different wavelengths:
one for reading DVDs and the other for reading CDs and CD-Rs. Variations on the
theme include Sony's "dual discrete optical pickup" with switchable pickup
assemblies with separate optics, Sony's dual-wavelength laser (to be initially
deployed on Playstation 2), 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. The MultiRead logo guarantees compatibility with CD-R and CD-RW media, but
unfortunately, few manufacturers are using it.
Bottom line: If you want a DVD player that can read CD-R discs, look a "dual
laser" or "dual optics" feature.
An effort to develop CD-R "Type II" media compatible with both CD and DVD
wavelengths was abandoned.
DVD-ROM drives can't record on any media. There are a few combination
DVD-ROM/CD-RW drives. Current writable DVD drives (see 4.3) can't record on
CD-R or CD-RW, although future versions will.
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 will.
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. About two thirds of DVD players can play Video CDs. 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
scale all 288 lines to fit.
Because PAL VCDs are encoded for 25 fps playback of 24 fps film, there is
usually a 4% speedup. 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 1.19).
All DVD-ROM computers can play Video CDs (with the right software).
Standard VCD players can't play DVDs.
Note: Many Asian VCDs achieve 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 CDPage.
Not generally. 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 480x480 (NSTC) or 480x576 (PAL)
resolution) and 2-channel MPEG-2 Layer II audio. 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 DVD170 player can be upgraded (using a special disc) to play SVCD
discs. 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.
See Jukka Aho's Super
Video CD Overview and Super Video CD FAQ for more
info.
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. Current 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 has yet to appear. Some people expect 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 standard VCD format, will play on any
player that can play VCDs (see 2.4.5).
See Jorg Kennis' CD-i FAQ for more
information on CD-i.
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 is a problem with Microsoft and other
CD/DVD-ROM drivers skipping track zero.
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 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
system. Pioneer's combination DVD/laserdisc players are the only DVD players
that can play CDVs.
LD/CDV players can't play DVDs. (See 2.5 for more LD
info.)
Mostly no. MP3 is the MPEG-1 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. MP3 can be played on computers with a DVD-ROM drive. A few DVD
players (Apex/REC/VDDV, I-Jam, Lasonic, Nintaus, Raite [AV
Phile/Hoyo/KiSS/Monica/Monyka/Tokai/Yamakawa], Sampo, Shinco) can play MP3 CDs.
(See 6.2 for company
Web sites.)
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 produces combo players that play laserdiscs and DVDs (and
also CDVs and audio CDs). Denon and Samsung are rumored to have LD/DVD players
in the works also.
When this question was first entered in the FAQ, before DVD was even
available, people wondered if DVD would replace laserdisc (and some argued it
never would -- that DVD would fail and it's adherents would come groveling back
to laserdisc). After DVD was released, it became clear that it had doomed
laserdisc to quick obscurity. Pioneer Entertainment, the long-time champion of
laserdisc, abandoned it in June of 1999. This was sooner than even Pioneer
thought possible, (in September 1998, Pioneer's president Kaneo Ito said the
company expected laserdisc products to be in the market for another
one-and-a-half to two years).
Laserdisc still fills important niches in education and training, but is
fading very quickly as an entertainment format. Existing players and discs will
still be around for a very long time, and new discs are still being produced,
since laserdisc has become well established over 20 years 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 level, and even then there's no
reason for laserdisc player owners to stop buying or playing laserdiscs,
especially rare titles that may not appear on DVD for a long while if ever. One
bright point is that laserdiscs (especially used discs) can now be had at
bargain prices.
- Features: DVD has the same basic features as CLV LD (scan, pause, search)
and CAV LD (freeze, slow) and adds branching, multiple camera angles, parental
control, video menus, interactivity, etc., although some of these features are
not available on all discs.
- Capacity: Single-layer DVD holds over 2 hours, dual-layer holds over 4
hours. CLV LD holds one hour per side, CAV holds half an hour. A CAV laserdisc
can hold 104,000 still images. DVD can hold thousands of still pictures
accompanied by hundreds of hours of audio and text.
- Convenience: An entire movie fits on one side of a DVD, so there's no need
to flip the disc or wait for the player to do it. DVDs are smaller and easier
to handle. DVD players can be portable, similar to CD players. Discs can be
easily and cheaply sent through the mail. On the other hand, laserdiscs have
larger covers for better art and text.
- Noise: Most LD players make a whirring noise that can be heard during
quiet segments of a movie. Most DVD players are as quiet as CD players.
- Audio: LD can have better quality on Dolby Surround soundtracks stored in
uncompressed PCM format. DVD has better quality on Dolby Digital or music only
(PCM). LD has 2 audio tracks: analog and digital. DVD has up to 8 audio
tracks. LD uses PCM audio sampled with 16 bits at 44.1 kHz. DVD LPCM audio can
use 16, 20, or 24 bit samples at 48 or 96 kHz (although PCM is not used with
most movies). LD has surround audio in Dolby Surround, Dolby Digital (AC-3),
and DTS formats. 5.1-channel surround sound is available by using one channel
of the analog track for AC-3 or both channels of the digital track for DTS.
DVD uses the same Dolby Digital surround sound, usually at a higher data rate
of 448 kbps, and can optionally include DTS (at data rates up to 1536 kbps
compared to LD's 1411 kbps, but in practice DTS data rates are often 768
kbps). DVD players convert Dolby Digital to Dolby Surround. The downmixing,
combined with the effects of compression, often results in lower-quality sound
than from LD Dolby Surround tracks.
- Video: DVD usually has better video. LD suffers from degradation inherent
in analog storage and in the composite NTSC or PAL video signal. DVD uses
digital video, and even though it's heavily compressed, most professionals
agree that when properly and carefully encoded it's virtually
indistinguishable from studio masters. Nevertheless, this doesn't mean that
the video quality of DVD is always better than LD. Only that it can be better.
Also keep in mind that the average television is of insufficient quality to
show much difference between LD and DVD. Home theater systems or HDTVs are
needed to take full advantage of the improved quality. The arguments about DVD
quality vs. LD quality will rage for a long time. The only final answer is to
compare them side by side and form your own opinion.
- Resolution: In numerical terms DVD has 345,600 pixels (720x480), which is
1.3 times LD's approximately 272,160 pixels (567x480). Widescreen DVD has 1.7
times the pixels of letterboxed LD (or 1.3 times anamorphic LD). As for lines
of horizontal resolution, DVD has about 500 while LD has about 425 (more info
in 3.4.1). In
analog output signal terms, typical luma frequency response maintains full
amplitude to between 5.0 and 5.5 MHz. This is below the 6.75 MHz native
frequency of the MPEG-2 digital signal. Chroma frequency response is one-half
that of luma. Laserdisc frequency response usually begins to fall off at 3
MHz. (All figures are for NTSC, not PAL.)
- Legacy titles: There are thousands of movies on laserdisc that will
probably never appear on DVD.
- Availability: DVD players and discs are available for purchase and rental
in thousands of outlets and on the Internet. LD players and discs are becoming
hard to find.
- Price: Low-cost DVD players are cheaper than the cheapest LD player, and
the success of DVD-ROM will inevitably drive the price to the under-$100 level
of CD players. Most movies on DVD cost less than on LD.
- Restrictions: For those outside the US, regional coding (see 1.10) is a definite
drawback of DVD. For some people Macrovision copy protection (see 1.11) is an
annoyance. Laserdisc has no copy protection and does not have regional
differences other than PAL vs. NTSC.
For more laserdisc info, see Leopold's FAQ at <www.cs.tut.fi/~leopold/Ld/FAQ/index.html>,
and Bob Niland's FAQs and overview at <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. ATSC standard in specific. The ATSC standard includes both
standard-definition (SD) and high-definition (HD) digital formats. The notation
H/DTV is often used to specifically refer to high-definition digital TV.
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.
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 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 fields/sec [30 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. CEA
expects 10 percent of U.S. households to have HDTV in 2003, 20 percent by 2005,
and 30 percent by 2006.
HDTV 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
(YCbCr) 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 for under $3000. The quality of a good DVD PC connected
to a data-grade video projector beats $30,000 line-doubler systems. (See NetTV and Digital Connection for product
examples. Video projectors are available from Barco, Dwin,
Electrohome, Faroudja, InFocus, Projectavision, Runco, Sharp, Sony, Vidikron, and others.)
Eventually the DVD-Video format will be upgraded to an "HD-DVD" format. See
2.12.
Note: There is a computer-based "DVD ripper" that was named after the
original Divx in an annoying little joke that has caused untold confusion. See
4.8 for more
info.
Depending on whom you ask, Divx (once known as ZoomTV) was either an
insidious evil scheme for greedy studios to control what you see in your own
living room or an innovative approach to video rental with cheap discs you could
get almost anywhere and keep for later viewings. On June 16, 1999, less than a
year after initial product trials, Digital Video Express announced that it was
closing down. Divx did not confuse or delay development of the DVD market nearly
as much as many people predicted (including yours truly). In fact, it probably
helped by stimulating Internet rental companies to provide better services and
prices, by encouraging manufacturers to offer more free discs with player
purchases, and by motivating studios to develop rental programs.
The company offered $100 rebate coupons to all owners of Divx players. This
made the players a good deal, since they can play open DVDs just as well as
other low-end players that cost more. The Divx billing computer will continue to
operate normally until June 30th, 2001, after which all Divx discs will
presumably become unplayable. Divx discs can no longer be upgraded to unlimited
play.
Developed by Circuit City and a Hollywood law firm, Divx was supported by
Disney (Buena Vista), Twentieth Century Fox, Paramount, Universal, MGM, and
DreamWorks SKG, all of which also released discs in "open DVD" format, since the
Divx agreement was non-exclusive. Harman/Kardon, JVC, Kenwood, Matsushita
(Panasonic), Pioneer, Thomson (RCA/Proscan/GE), and Zenith announced Divx
players, though some never came to market. (Divx models are Panasonic X410,
Proscan PS8680Z, RCA RC5230Z and RC5231Z, and Zenith DVX2100.) The studios and
hardware makers supporting Divx were given incentives in the form of guaranteed
licensing payments totaling over $110 million. Divx discs were manufactured by
Nimbus, Panasonic, and Pioneer. Circuit City lost over $114 million (after tax
writeoffs) on Divx.
Divx was a pay-per-viewing-period variation of DVD. Divx discs sold for
$4.50. Once inserted into a Divx player the disc would play normally (allowing
the viewer to pause, rewind, even put in another disc before finishing the first
disc) for the next 48 hours, after which the "owner" had to pay $3.25 to unlock
it for another 48 hours. A Divx DVD player, which cost about $100 more than a
regular player, had to be hooked up to a phone line so it could call an 800
number for about 20 seconds during the night once each month to upload billing
information. Most Divx discs could be converted to DivxSilver status by paying
an additional fee (usually $20) to allow unlimited plays on a single account (as
of Dec 1998, 85% of Divx discs were convertible). Unlimited-playback DivxGold
discs were announced but never produced. Divx players can also play regular DVD
discs, but Divx discs do not play in standard DVD players. Divx discs are
serialized (with a barcode in the standard Burst Cutting Area) and in addition
to normal DVD copy protection (see 1.11) they employ
watermarking of the video, modified channel modulation, and triple DES
encryption (three 56-bit keys) of serial communications. Divx technology never
worked on PCs, which undoubtedly contributed to its demise. Because of the DES
encryption, Divx technology may not have been allowed outside the U.S.
Divx was originally announced for summer 1998 release. Limited trials began
June 8, 1998 in San Francisco, CA and Richmond, VA. The only available player
was from Zenith (which at the time was in Chapter 11 bankruptcy), and the
promised 150 movies had dwindled to 14. The limited nationwide rollout (with one
Zenith player model and 150 movies in 190 stores) began on September 25, 1998.
By the end of 1998 about 87,000 Divx players (from four models available) and
535,000 Divx discs were sold (from about 300 titles available). The company
apparently counted the five discs bundled with each player, which means only
100,000 additional discs were sold. By March 1999, 420 Divx titles were
available (compared to over 3,500 open DVD titles).
For more information see the Divx Owner's
Association.
Advantages of Divx:
- Viewing could be delayed, unlike rentals.
- Discs need not be returned. No late fees.
- You could watch the movie again for a small fee. Initial cost of "owning"
a disc was reduced.
- Discs could be unlocked for unlimited viewing (Divx Silver), an
inexpensive way to preview before deciding to purchase.
- The disc is new; no damage from previous renters.
- The "rental" market was opened up to other retailers, including mail
order.
- Studios got more control over the use of their content.
- You received special offers from studios in your Divx mailbox.
- Divx players (with better quality and features than comparable players)
were a steal after Divx went out of business.
Disadvantages of Divx :
- Higher player cost (about $100 more at first, about $50 later).
- Although discs did not have to be returned, the viewer still had to go to
the effort of purchasing the disc. Cable/satellite pay per view is more
convenient.
- Higher cost than for regular DVD rental ($3 to $7 vs. $2 to $4). There
were few obstacles to the company raising prices later, since it had a
monopoly.
- Casual quick viewing (looking for a name in the credits, playing a
favorite scene, watching supplements) required paying a fee.
- Most Divx titles were pan & scan (see 3.5) without extras
such as foreign language tracks, subtitles, biographies, trailers, and
commentaries.
- The player had to be hooked to your phone line, possibly requiring a new
jack in your living room or a phone extension cable strung across it. (Players
required a connection once a month or so, so you could periodically connect it
to a phone line.)
- Divx couldn't be used in mobile environments, such as a van or RV, unless
you took it out and connected it to a phone line about once a month.
- The Divx central computer collected information about your viewing habits,
as do cable/satellite pay-per-view services and large rental chains.
(According to Divx, the law did not allow them to use the information for
resale and marketing.)
- Divx players included a "mailbox" for companies to send you unsolicited
offers (i.e., spam).
- Those who didn't lock out their Divx player could receive unexpected bills
when their kids or visitors played Divx discs.
- Divx discs wouldn't play in regular DVD players or on PCs with DVD-ROM
drives. Some uninformed consumers bought Divx discs only to find they wouldn't
play in their non-Divx player.
- Unlocked Silver discs would only work in players on the same account.
Playback in a friend's Divx player would incur a charge. (Gold discs, which
were never released, would have played without charge in all Divx players.)
- There was no market for used Divx discs.
- Divx discs are unplayable after June 2001.
- Divx players were never available outside the U.S. and Canada.
Why in the world would you want to degrade DVD's beautiful digital picture by
copying it to analog tape? Especially since you lose the interactive menus and
other nice features.
If you really want to do this, hook the audio/video outputs of the TV player
to the audio/video inputs of your VCR, then record the disc to tape. You'll
discover that most of the time the resulting tape is garbled and unwatchable.
This is because of the Macrovision feature designed to prevent you from doing
this. See 1.11.
Not for a long time. HD-DVD "technology demonstrations" being made by various
companies do not mean that HD-DVD is around the corner (the demonstrations mean
only that companies are busy jockeying for technology and patent positions in
developing the future DVD format). Consider that U.S. HDTV was widely
anticipated to be available in 1989, yet was not finalized until 1996, and did
not appear until 1998. And has it made your current TV obsolete yet?
HD-DVD (HD stands for both high-density and high-definition) may be available
in 2003 at the very earliest, though 2006 is more likely. It will use blue or
violet lasers to read smaller pits, increasing data capacity to around 20 GB per
layer. MPEG-2 Progressive Profile--or perhaps another format such as H.263--will
probably be used to encode the video. All ATSC and DVB formats will be
supported, possibly with the addition of 1080p24. HD-DVD players will play
current DVD discs and will make them look even better (with progressive-scan
video and picture processing), but new HD-DVD discs won't be playable in older
DVD players (unless one side is HD and the other standard DVD).
Ironically, computers will support HDTV before settop players do, since 2x
DVD-ROM drives coupled with appropriate playback and display hardware meet the
19 Mbps data rate needed for HDTV. This has led to various "720p DVD" projects,
which use the existing DVD format to store video in 1280x720 resolution at 24
progressive frames per second. It's possible that 720p DVDs can be made
compatible with existing players (which would only play the 480-line line
data).
Note: The term HDVD has already been
taken for "high-density volumetric display."
Some have speculated that a "double-headed" player reading both sides of the
disc at the same time could double the data rate or provide an enhancement
stream for applications such as HDTV. This is currently impossible since the
track spirals go in opposite directions (unless all four layers are used). The
DVD spec would have to be changed to allow reverse spirals on layer 0. Even
then, keeping both sides in sync, especially with MPEG-2's variable bit rate,
would require independently tracking heads, precise track and pit spacing, and a
larger, more sophisticated track buffer. Another option would be to use two
heads to read both layers of one side simultaneously. This is technically
feasible but has no advantage over reading one layer twice as fast, which is
simpler and cheaper.
See 2.9 for more
information about HDTV and DVD.
Who knows? So far Constellation 3D's FMD
(fluorescent multilayer disc) isn't out of the lab. You can be sure only that
the reports of FMD causing the early death of DVD are wildly exaggerated and not
founded in reality.
Fluorescent multilayer technology, which can be used in cards or discs, aims
a laser at fluorescent recording material, causing it to emit light. Since it
doesn't depend on reflected laser light, it's possible to create many data
layers (C3D has prototyped 50 layers in its lab). It can use the same 650 nm
laser as DVD, so FMD drives could be made to read DVDs. In June 2000, C3D
announced a program to make FMDs with 25 GB per side that would be readable by
DVD drives with a "minor and inexpensive modification."
FMD is a new technology, with no track record, supported by one small
company. DVD is based on decades of optical storage technology development by
dozens of companies. It's possible that FMD could become established in few
years, but DVD is already so entrenched that FMD drives will have to read DVDs
in order to succeed. So there is little worry of DVD becoming obsolete any time
soon. Perhaps FMD will be the third generation of the DVD format, following the
high-density blue-laser version currently under development (see 2.12)
Video outputs
Most DVD players have the following video output connections, which can carry
an NTSC, PAL, or SECAM signal.
- Composite video (CVBS). Standard yellow RCA video plug, combines all three
video signals into one.
- S-video (Y/C). 4-pin round plug or as part of SCART connector, separates
brightness signal (Y) from two color signals (C).
Some players may have additional video connections:
- Component interlaced analog video. Keeps all three video signals
separate.
- Y'PbPr format: 3 RCA or BNC connectors.
- RGB format: SCART
connector or 3 RCA or BNC connectors.
- Component progressive analog video. Keeps all three video signals
separate.
- Y'PbPr format: 3 RCA connectors.
- RGB format: SCART
connector or 3 RCA or BNC connectors.
- RF video. For connecting the TV antenna input on channel 3 or 4.
-
Screw-on F-type connector. May require an adapter.
Most of the DVD players with component video outputs use YUV (Y'PbPr), which
is incompatible with RGB equipment. European players with SCART connectors have
RGB outputs. YUV to RGB transcoders are rumored to be available for $200-$300,
but seem hard to track down. A $700 converter is available from avscience, and $900 converter, the CVC 100,
is available from Extron. Converters are
also available from Altinex, Kramer, Monster Cable, and others. For
progressive scan you need a converter that can handle 31.5 kHz signals.
Converters from s-video are also an option (Markertek Video Supply,
800-522-2025).
Note: The correct term for analog color-difference output is Y'Pb'Pr',
not Y'Cb'Cr' (which is digital, not analog). To simplify things, this FAQ uses
the term YUV in the generic sense to refer to analog color difference
signals.
No DVD players have yet been announced with digital video outputs, but
digital output will soon be available using FireWire (IEEE 1394) connectors.
Audio outputs
Most DVD players have the following audio output connections.
- Analog stereo audio. May have Dolby Surround encoding, depending on the
disc.
- Two RCA connectors, red and white.
- Digital audio. 1 to 5.1 channels. Raw digital audio in PCM, MLP, Dolby
Digital (AC-3), DTS, or MPEG-2 format. Requires an amplifier/receiver with a
built-in decoder (or a separate external decoder).
- S/P DIF coax format:
RCA connector. (IEC-958 Type II)
- Toslink format: square optical
connector. (EIAJ CP-340 and EIAJ CP-1201)
Some players may have additional audio connections:
- Multichannel analog audio. Requires a multichannel-ready or "Dolby Digital
ready" amplifier/receiver with 6 inputs.
- Six RCA connectors or one DB-25
connectors.
- AC-3 RF audio. Only on combination LD/DVD players. Only carries audio from
AC-3 laserdiscs.
- One RCA connector.
Some players and receivers support only S/P DIF or only Toslink. If your
player and receiver don't match, you'll need a converter such as the Audio Authority 977 Midiman C02, COP 1, or POF.
Some players can output 96/24 PCM audio using a non-standard variation of
IEC-958 running at 6.2 MHz (6.144 Mbps) instead of the normal limit of 3.1 MHz.
Note: The CSS license does not allow digital PCM
output of CSS-protected material at 96 kHz. The player must downsample to 48
kHz.
It depends on your audio/video system and your DVD player. Most DVD players
have 2 or 3 video hookup options and 3 audio hookup options. Choose the option
with the best quality (indicated below) that is supported by your video and
audio systems. See 3.1 for output
connector details.
Video hookup
- Progressive video (very best): A few players have progressive-scan
YUV (Y'Pb'Pr') or RGB (European players only) component video output. Hook
decent-quality cables from the three video outputs of the player to the three
video inputs of a progressive-scan line multiplier or a progressive-scan TV.
Toshiba's version is called ColorStream PRO. Progressive video preserves
the progressive nature of most movies, providing a film-like, flicker-free
image with improved vertical resolution and smoother motion. DVD computers can
also produce progressive video from DVD. In this case, use a 15-pin computer
video cable to connect the VGA output of the PC to the VGA input of a monitor
or projector. If the projector only has RGB or YPbPr inputs, you'll need a
converter such as the Audio Authority
9A60.
See 1.40, 2.12, and 4.1 for more
information on progressive video.
- Component video (best): Some U.S. and Japanese players have
interlaced component YUV (Y'Pb'Pr') video output. Connectors may be labeled
YUV, color difference, YPbPr, or Y/B-Y/R-Y, and may be colored green/blue/red.
(Some players incorrectly label the output as YCbCr.) Some players have RGB
component video output via a 21-pin SCART connector or 3 RCA or BNC connectors
labeled R/G/B. Hook cables from the three video outputs of the player to the
three video inputs of the display, or hook a SCART cable from the player to
the display.
Note: There is no standardization on the output interface
format (voltage and setup). Players apparently use SMPTE 253M (286 mV sync, 0% luma setup with 700 mV peak, +/-300 mV color
excursion), Betacam (286 mV sync, 7.5% luma setup
with 714 mV peak, +/-350 mV color excursion), M-II (300 mV sync, 7.5% luma setup with 700 mV peak, +/-324.5 mV
color excursion), or non-standard variations. Note that outputs with
zero IRE setup can provide a wider range of luma values for a slightly better
picture. For equipment with RGB input, a YUV converter is usually needed. See
section 3.1.
- S-video (very good): Almost all players have s-video output.
S-video looks much better than composite video, and only slightly inferior to
component video. Hook an s-video cable from the player to the display (or to
an A/V receiver that can switch s-video). The round, 4-pin connector may be
labeled Y/C, s-video, or S-VHS.
- Composite video (ok): All DVD players have standard RCA (Cinch)
baseband video connectors. Hook a standard video cable from the player to the
display (or to an A/V receiver ). The connectors are usually yellow and may be
labeled video, CVBS, composite, or baseband.
- RF video (worst): You should use this connection only if you have
an old TV that has only a screw-on antenna input. Most DVD players don't have
RF output, so you will probably need to buy an RF modulator (~$30 at Radio
Shack). (See warning below about using a VCR as an RF modulator.) If the
player has built-in RF output it will include audio, although it may only be
mono. Connect a coax cable from the yellow video output of the player to the
input of the modulator. If you are not hooking the player up to a separate
stereo system, then connect a coax cable from the left audio output of the
player to the input of the modulator. (If you have a stereo modulator, connect
another cable for the right channel.) Connect a coax antenna cable from the
modulator to the TV. You may need a 300 ohm to 75 ohm adapter. Tune the TV to
channel 3 or 4 and set the switch on the modulator or the back of the player
to match.
Warning: If you connect your DVD player to a VCR and then to your TV, you may
have problems with discs that enable the player's Macrovision circuit. See 3.2.1.
Warning: Some video projectors don't recognize the 4.43 NTSC signal from NTSC
discs in PAL players (see 1.19). They see the
60Hz scanning frequency and switch to NSTC even though the color subcarrier is
in PAL format.
Note: Most DVD players support widescreen signaling, which tells a widescreen
display what the aspect ratio is so that it can automatically adjust. One
standard (ITU-R BT.1119, used mostly in Europe) includes information in a video
scanline. Another standard, for Y/C connectors, adds a 5V DC signal to the
chroma line to designate a widescreen signal. Unfortunately, some switchers and
amps throw away the DC component instead of passing it on to the TV.
For more information on conversions between formats, see the amazing Notes on Video Conversion
from the Sci.Electronics.Repair FAQ.
Audio hookup
Note: All DVD players have either a built-in Dolby Digital (AC-3) or MPEG
audio decoder, or both. The decoder translates multi-channel audio into PCM
audio. This is fed to the digital output and also converted to analog for
standard audio output. Most players have only a 2-channel-output decoder, but
some provide 6-channel output (details below).
- Digital audio (best): Almost all DVD players have digital audio
outputs. The same output can carry Dolby Digital (AC-3), PCM audio (including
PCM from CDs), MLP audio (from DVD-Audio discs), DTS, and MPEG-2 audio
(PAL/SECAM players only). For PCM, a digital receiver or an outboard DAC is
required. For all other formats, the appropriate decoder is required in the
receiver/amplifier or as a separate audio processor. DTS discs require a
player with the "DTS Digital Out" mark (older players won't recognize DTS
tracks), however, all DVD players can play DTS CDs if a DTS decoder is
connected to the digital output (PCM signal). Some DVD players have coax
connectors (SP/DIF), some have fiber-optic connectors (Toslink), and many have
both. There are endless arguments over which of these is better. Coax seems to
have more advocates, since it's inherently simpler. Optical cable is not
affected by electromagnetic interference, but it's more fragile and can't
curve tightly. Suffice it to say that since the signal is digital, a quality
cable of either type will provide similar results. Hook a 75-ohm coax cable or
a fiber-optic cable between the player and the receiver/processor. (You might
need a converter, see 3.1.) Some players
provide separate connectors for DD/MPEG and PCM. On others, you may need to
select the desired output format with the player setup menu or a switch on the
back of the player.
Note: Make sure you use a quality cable; a cheap
RCA patch cable may cause the audio to sound poor or not work at
all.
Note: Connecting to the AC-3/RF (laserdisc) input will not work
unless your receiver/decoder can autoswitch, since DVD digital audio is not in
RF format (see below).
- Component analog audio (good): Some players provide 6-channel
analog output from the internal Dolby Digital decoder. The digital-to-analog
conversion quality may be better or worse than an external decoder. A
receiver/amplifier with 6 inputs (or more than one amplifier) is required;
this type of unit is often called "Dolby Digital ready" or "AC-3 ready."
Unfortunately, in most cases you will be unable to adjust the volume of
individual channels. Hook 6 audio cables to the RCA connectors on the player
and to the matching connectors on the receiver/amplifier. Some receivers
require an adapter cable with a DB-25 connector on one end and RCA connectors
on the other.
Note: Until there is a digital connection standard,
the only way to get 6-channel PCM output from DVD-Audio players will be with
analog connections. If you plan to get a DVD-Audio player, you'll need a
receiver with multichannel inputs.
- Stereo/surround analog audio (ok): All DVD players include two RCA
connectors for stereo output. Any disc with Dolby Digital or MPEG-2 audio will
automatically be decoded and downmixed to Dolby Surround output for connection
to a regular stereo system or a Dolby Surround/Pro Logic system. Connect two
audio cables between the player and a receiver, amplifier, or TV. Connectors
may be labeled audio or left/right; left is usually white, right is usually
red.
- RF digital audio (LD only): Combination LD/DVD players include AC-3
RF output for digital audio from laserdiscs. Hook a coax cable to the AC-3 RF
input of the receiver/processor. Note: digital audio from DVDs does not come
out of the RF output, it comes out of the optical/coax outputs. Analog audio
from LDs will come out the stereo connectors, so three separate audio hookups
are required to cover all variations.
It's not a good idea to route the video from your DVD player through your
VCR. Most movies use Macrovision protection (see 1.11), which causes
problems such as a repeated darkening and lightening of the picture. If your TV
doesn't have a direct video input, you may need a separate RF converter (see 3.2). Or better yet,
get a new TV with s-video inputs.
You may also have problems with a TV/VCR combo, since many of them
route the video input through the VCR circuitry. The only solution is to get a
box to strip Macrovision (see 1.11).
The number one cause of bad video is a poorly adjusted TV. The high fidelity
of DVD video demands much more from the display. Turn the sharpness and
brightness down. See 1.3 for more
information. For technical details of TV calibration, see Anthony Haukap's FAQ: How To Adjust a
TV.
If you get audio hum or noisy video, it's probably caused by interference or
a ground loop. Try a shorter cable. Make sure the cable is adequately shielded.
Try turning off all equipment except the pieces you are testing. Try moving
things farther apart. Try plugging into a different circuit. Wrap your entire
house in tinfoil. Make sure all equipment is plugged into the same outlet. For
more on ground loops, see http://www.hut.fi/Misc/Electronics/docs/groundloop/.
There are many variations on the DVD theme. There are two physical sizes: 12
cm (4.7 inches) and 8 cm (3.1 inches), both 1.2 mm thick, made of two 0.6mm
substrates glued together. These are the same form factors as CD. A DVD disc can
be single-sided or double-sided. Each side can have one or two layers of data.
The amount of video a disc can hold depends on how much audio accompanies it and
how heavily the video and audio are compressed. The oft-quoted figure of 133
minutes is apocryphal: a DVD with only one audio track easily holds over 160
minutes, and a single layer can actually hold up to 9 hours of video and audio
if it's compressed to VHS quality.
At a rough average rate of 4.7 Mbps (3.5 Mbps for video, 1.2 Mbps for three
5.1-channel soundtracks), a single-layer DVD can hold a little over two hours. A
two-hour movie with three soundtracks can average 5.2 Mbps. A dual-layer disc
can hold a two-hour movie at an average of 9.5 Mbps (very close to the 10.08
Mbps limit).
A DVD-Video disc containing mostly audio can play for 13 hours (24 hours with
dual layers) using 48/16 PCM (slightly better than CD quality). It can play 160
hours of audio (or a whopping 295 hours with dual layers) using Dolby Digital 64
kbps compression of monophonic audio, which is perfect for audio books.
Capacities of DVD:
For reference, a CD-ROM holds about 650 megabytes, which is 0.64 gigabytes or
0.68 billion bytes. In the list below, SS/DS means single-/double-sided,
SL/DL/ML means single-/dual-/mixed-layer (mixed means single layer on one side,
double layer on the other side), gig means gigabytes (2^30), BB means billions
of bytes (10^9). See note about giga vs. billion in section 7.2.
| DVD-5 (12 cm, SS/SL) |
4.38 gig (4.70 BB) of data, over 2 hours of video |
| DVD-9 (12 cm, SS/DL) |
7.95 gig (8.54 BB), about 4 hours |
| DVD-10 (12 cm, DS/SL) |
8.75 gig (9.40 BB), about 4.5 hours |
| DVD-14 (12 cm, DS/ML) |
12.33 gig (13.24 BB), about 6.5 hours |
| DVD-18 (12 cm, DS/DL) |
15.90 gig (17.08 BB), over 8 hours |
| DVD-1 (8 cm, SS/SL) |
1.36 gig (1.46 BB), about half an hour |
| DVD-2 (8 cm, SS/DL) |
2.48 gig (2.66 BB), about 1.3 hours |
| DVD-3 (8 cm, DS/SL) |
2.72 gig (2.92 BB), about 1.4 hours |
| DVD-4 (8 cm, DS/DL) |
4.95 gig (5.32 BB), about 2.5 hours |
| DVD-R 1.0 (12 cm, SS/SL) |
3.68 gig (3.95 BB) |
| DVD-R 2.0 (12 cm, SS/SL) |
4.38 gig (4.70 BB); 8.75 gig for rare DS discs |
| DVD-RW 2.0 (12 cm, SS/SL) |
4.38 gig (4.70 BB); 8.75 gig for rare DS discs |
| DVD-RAM 1.0 (12 cm, SS/SL) |
2.40 gig (2.58 BB) |
| DVD-RAM 1.0 (12 cm, DS/SL) |
4.80 gig (5.16 BB) |
| DVD-RAM 2.0 (12 cm, SS/SL) |
4.38 gig (4.70 BB) |
| DVD-RAM 2.0 (12 cm, DS/SL) |
8.75 gig (9.40 BB) |
| DVD-RAM 2.0 (8 cm, DS/SL) |
1.36 gig (1.46 BB) |
| CD-ROM (12 cm, SS/SL) |
0.635 gig (0.650 BB) |
| CD-ROM (8 cm, SS/SL) |
0.180 gig (0.194 BB) |
Tip: It takes about two gigabytes to store one hour of average video.
The increase in capacity from CD-ROM is due to: 1) smaller pit length
(~2.08x), 2) tighter tracks (~2.16x), 3) slightly larger data area (~1.02x), 4)
more efficient channel bit modulation (~1.06x), 5) more efficient error
correction (~1.32x), 6) less sector overhead (~1.06x). Total increase for a
single layer is about 7 times a standard CD-ROM. There's a slightly different
explanation at <www.mpeg.org/MPEG/DVD/General/Gain.html>.
The capacity of a dual-layer disc is slightly less than double that of a
single-layer disc. The laser has to read "through" the outer layer to the inner
layer (a distance of 20 to 70 microns). To reduce inter-layer crosstalk, the
minimum pit length of both layers is increased from 0.4 um to 0.44 um. To
compensate, the reference scanning velocity is slightly faster -- 3.84 m/s, as
opposed to 3.49 m/s for single layer discs. Longer pits, spaced farther apart,
are easier to read correctly and are less susceptible to jitter. The increased
length means fewer pits per revolution, which results in reduced capacity per
layer.
See 4.3 for
details of writable DVD. More info on disc specifications and manufacturing can
be found at Disctronics, Cinram. Panasonic, Technicolor,
and other disc replicator sites.
The first commercial DVD-18 title, The Stand, was released in October
1999. It will still take a while for these super-size discs to become common. A
DVD-18 requires a completely different way of creating two layers. A
single-sided, dual-layer disc (DVD-9) is produced by putting one data layer on
each substrate and gluing the halves together with transparent adhesive so that
the pickup laser can read both layers from one side. But in order to get four
layers, each substrate needs to hold two. This requires stamping a second data
layer on top of the first, a much more complicated prospect. Even after new
equipment is developed and installed in production lines, the yield (number of
usable discs compared to bad discs) will be quite low until the process is fine
tuned.
WAMO and others continue to announce progress with DVD-18 processes, but
given how long it took for production of dual-layer, single-sided discs to
become practical, it will take even longer before the yields of DS/DL discs can
meet the replication demands of mainstream movie distribution, especially since
low yields mean higher replication costs. In the interim we'll see DVD-14s (two
layers on one side, one layer on the other side), since they're a little easier
to produce.
(My prediction in this FAQ, as of December 1998, was that we wouldn't see
commercial DVD-18 discs until fall 1999, in spite of many rumors that they would
appear sooner.)
DVD-Video is an application of DVD-ROM. DVD-Video is also an application of
MPEG-2. This means the DVD format defines subsets of these standards to be
applied in practice as DVD-Video. DVD-ROM can contain any desired digital
information, but DVD-Video is limited to certain data types designed for
television reproduction.
A disc has one track (stream) of MPEG-2 constant bit rate (CBR) or variable
bit rate (VBR) compressed digital video. A restricted version of MPEG-2 Main
Profile at Main Level (MP@ML) is used. SP@ML is also supported. MPEG-1 CBR and
VBR video is also allowed. 525/60 (NTSC, 29.97 interlaced frames/sec) and 625/50
(PAL, 25 interlaced frames/sec) video display systems are expressly supported.
Coded frame rates of 24 fps progressive from film, 25 fps interlaced from PAL
video, and 29.97 fps interlaced from NTSC video are typical. MPEG-2
progressive_sequence is not allowed, but interlaced sequences can contain
progressive pictures and progressive macroblocks. In the case of 24 fps source,
the encoder embeds MPEG-2 repeat_first_field flags into the video stream to make
the decoder either perform 2-3 pulldown for 60Hz (59.94) displays or 2-2
pulldown (with resulting 4% speedup) for 50Hz displays. In other words, the
player doesn't really "know" what the encoded rate is, it simply follows the
MPEG-2 encoder's instructions to produce the predetermined display rate of 25
fps or 29.97 fps. (Very few players convert from PAL to NTSC or NTSC to PAL. See
1.19.)
It's interesting to note that even interlaced source video is often encoded
as progressive-structured MPEG pictures, with interlaced field-encoded
macroblocks used only when needed for motion. A computer can mostly ignore the
repeat_first_field flags and re-interleave (weave) the video fields back
into full-resolution progressive frames, which works especially well at 72 Hz
refresh rate (3x24). Computers can improve the quality of interlaced source by
doubling the lines in fields (bobbing) and displaying them as progressive
frames at twice the normal rate. Most film source is encoded progressive (the
inverse telecine process in the encoder removes duplicate 2-3 pulldown fields
from videotape source); most video sources are encoded interlaced. These may be
mixed on the same disc, such as an interlaced logo followed by a progressive
movie.
See 3.8 for an
explanation of progressive and interlaced scanning. See 1.40 for
progressive-scan players. See the MPEG page <http://www.mpeg.org/> for more information on
MPEG-2 video.
Picture dimensions are max 720x480 (for 525/60 NTSC display) or 720x576 (for
625/50 PAL/SECAM display). Pictures are subsampled from 4:2:2 ITU-R BT.601 down
to 4:2:0, allocating an average of 12 bits/pixel in Y'CbCr format. (Color depth
is 24 bits, since color samples are shared across 4 pixels.) The uncompressed
source is 124.416 Mbps for video source (720x480x12x30 or 720x576x12x25), or
either 99.533 or 119.439 Mbps for film source (720x480x12x24 or 720x576x12x24).
In analog output terms, lines of horizontal resolution is usually around 500,
but can go up to 540 (see 3.4.1). Typical luma
frequency response maintains full amplitude to between 5.0 and 5.5 MHz. This is
below the 6.75 MHz native frequency of the MPEG-2 digital signal (in other
words, most players fall short of reproducing the full quality of DVD). Chroma
frequency response is half that of luma.
Different players use different numbers of bits for the video
digital-to-analog converter. Current best-quality players use 10 bits. This has
nothing to do with the MPEG decoding process, since each original component
signal is limited to 8 bits per sample. More bits in the player provide more
"headroom" and more signal levels during digital-to-analog conversion, which can
help produce a better picture.
Maximum video bit rate is 9.8 Mbps. The "average" video bit rate is 3.5 but
depends entirely on the length, quality, amount of audio, etc. This is a 36:1
reduction from uncompressed 124 Mbps video source (or a 28:1 reduction from 100
Mbps film source). Raw channel data is read off the disc at a constant 26.16
Mbps. After 8/16 demodulation it's down to 13.08 Mbps. After error correction
the user data stream goes into the track buffer at a constant 11.08 Mbps. The
track buffer feeds system stream data out at a variable rate of up to 10.08
Mbps. After system overhead, the maximum rate of combined elementary streams
(audio + video + subpicture) is 10.08. MPEG-1 video rate is limited to 1.856
Mbps with a typical rate of 1.15 Mbps.
Still frames (encoded as MPEG-2 I-frames) are supported and can be displayed
for a specific amount of time or indefinitely. These are generally used for
menus. Still frames can be accompanied by audio.
A disc also can have up to 32 subpicture streams that overlay the video for
subtitles, captions for the hard of hearing, captions for children, karaoke,
menus, simple animation, etc. These are full-screen, run-length-encoded bitmaps
with two bits per pixel, giving four color values and four transparency values.
For each group of subpictures, four colors are selected from a palette of 16
(from the YCbCr gamut), and four contrast values are selected out of 16 levels
from transparent to opaque. Subpicture display command sequences can be used to
create effects such as scroll, move, color/highlight, and fade. The maximum
subpicture data rate is 3.36 Mbps, with a maximum size per frame of 53220
bytes.
In addition to subtitles in subpicture streams, DVD also supports NTSC Closed
Captions. Closed Caption text is stored in the video stream as MPEG-2 user data
(in packet headers) and is regenerated by the player as a line-21 analog
waveform in the video signal, which then must be decoded by a Closed Caption
decoder in the television. Although the DVD-Video spec mentions NTSC only, there
is no technical reason PAL/SECAM DVD players could not be made to output the
Closed Caption text in World System Teletext (WST) format; the only trick is to
deal with frame rate differences. Unfortunate note: DVD Closed Caption MPEG-2
storage format is slightly different than the ATSC format. See 1.45 for more about
Closed Captions.
Everyone gets confused by the term "lines of horizontal resolution," also
known as LoHR or TVL. It's a carryover from analog video, it's poorly
understood, it's inconsistently measured and reported by manufacturers, but
we're stuck with it until all video is digital and we can just report resolution
in pixels.
Technically, lines of horizontal resolution refers to visually resolvable
vertical lines per picture height. In other words, it's measured by counting
the number of vertical black and white lines that can be distinguished an area
that is as wide as the picture is high. The idea is to make the measurement
independent of the aspect ratio. Lines of horizontal resolution applies both to
television displays and to signal formats such as that produced by a DVD player.
Most TVs have ludicrously high numbers listed for their horizontal
resolution.
Since DVD has 720 horizontal pixels (on both NTSC and PAL discs), the
horizontal resolution can be calculated by dividing 720 by 1.33 (for a 4:3
aspect ratio) to get 540 lines. On a 1.78 (16:9) display, you get 405 lines. In
practice, most DVD players provide about 500 lines instead of 540 because of
filtering and low-quality digital-to-analog converters. VHS has about 230 (172
widescreen) lines, broadcast TV has about 330 (248 widescreen), and laserdisc
has about 425 (318 widescreen).
Don't confuse lines of horizontal resolution (resolution along the x axis)
with scan lines (resolution along the y axis). DVD produces 480 scan lines of
active picture for NTSC and 576 for PAL. The NTSC standard has 525 total scan
lines, but only 480 to 483 or so are visible. (The extra lines are black. They
contain sync pulses and other information, such as the Closed Captions that are
encoded into line # 21). PAL has 625 total scan lines, but only about 576 to 580
are visible. Since all video formats (VHS, LD, broadcast, etc.) have the same
number of scan lines, it's the horizontal resolution that makes the big
difference in picture quality.
For more information, see Allan Jayne's TV and Video Resolution
Explained.
Video can be stored on a DVD in 4:3 format (standard TV shape) or 16:9
(widescreen). The width-to-height ratio of standard televisions is 4 to 3; in
other words, 1.33 times wider than high. New widescreen televisions,
specifically those designed for HDTV, have a ratio of 16 to 9; that is, 1.78
times wider than high.
DVD is specially designed to support widescreen displays. Widescreen 16:9
video, such as from a 16:9 video camera, can be stored on the disc in
anamorphic form, meaning the picture is squeezed horizontally to fit the
standard 4:3 rectangle, then unsqueezed during playback.
Things get more complicated when film is transferred to video, since most
movies today have an aspect ratio of 1.66, 1.85 ("flat"), or 2.40 ("scope").
Since these don't match 1.33 or 1.78 TV shapes, two processes are employed to
make various movie pegs fit TV holes:
Letterbox (often abbreviated to LBX) means the video is presented in
its theatrical aspect ratio, which is wider than standard or widescreen TV.
Black bars, called mattes, are used to cover the gaps at the top and
bottom. A 1.85 movie that has been letterboxed for 1.33 display has thinner
mattes than a 2.4 movie letterboxed to 1.33 (28% of display height vs. 44%),
although the former are about the same thickness as those of a 2.4 movie
letterboxed to 1.78 (26% of display height). The mattes used to letterbox a 1.85
movie for 1.78 display are so thin (2%) that they're hidden by the overscan of
most widescreen TVs. Some movies, especially animated features and European
films, have an aspect ratio of 1.66, which can be letterboxed for 1.33 display
or sideboxed for 1.78 display.
Pan & scan means the thinner TV "window" is panned and zoomed
across the wider movie picture, chopping off the sides. However, most movies
today are shot soft matte, which means a full 1.33 aspect film frame is
used. (The cinematographer has two sets of frame marks in her viewfinder, one
for 1.33 and one for 1.85, so she can allow for both formats.) The top and
bottom are masked off in the theater, but when the film is transferred to video
the full 1.33 frame can be used in the pan & scan process. Pan & scan is
primarily used for 1.33 formatting, not for 1.78 formatting, since widescreen
fans prefer that letterboxing be used to preserve the theatrical effect.
For more details and nice visual aids see Leopold's How Film Is Transferred to
Video page. A list of movie aspect ratios is at <cheezmo.com/wsmc>.
Once the video is formatted to full-frame or widescreen form, it's encoded
and stored on DVD discs. DVD players have four playback modes, one for 4:3 video
and three for 16:9 video:
- full frame (4:3 video for 4:3 display)
- auto letterbox (16:9 video for 4:3 display)
- auto pan & scan (16:9 video for 4:3 display)
- widescreen (16:9 video for 16:9 display)
Video stored in 4:3 format is not changed by the player. It will appear
normally on a standard 4:3 display. Widescreen systems will either enlarge it or
add black bars to the sides. 4:3 video may have been formatted with letterboxing
or pan & scan before being transferred to DVD. All formatting done to the
video prior to it being stored on the disc is transparent to the player. It
merely reproduces it as a standard 4:3 TV picture. Video that is letterboxed
before being encoded can be flagged so that the player will tell a widescreen TV
to automatically expand the picture. Unfortunately, some discs (such as Fargo)
do not flag the video properly. And worse, some players ignore the flags.
The beauty of anamorphosis is that less of the picture is wasted on letterbox
mattes. DVD has a frame size designed for 1.33 display, so the video still has
to be made to fit, but because it's only squeezed horizontally, 33% more pixels
(25% of the total pixels in a video frame) are used to store active picture
instead of black. Anamorphic video is best displayed on widescreen equipment,
which stretches the video back out to its original width. Alternatively, many
new 4:3 TV's can reduce the vertical scan area to restore the proper aspect
ratio without losing resolution (an automatic trigger signal is sent to European
TVs on SCART pin 8). Even though almost all computers have 4:3 monitors, they
have higher resolution than TVs so they can display the full widescreen picture
in a window (854x480 pixels or bigger for NTSC; 1024x576 or bigger for PAL).
Anamorphic video can be converted by the player for display on standard 4:3
TVs in letterbox or pan & scan form. If anamorphic video is shown unchanged
on a standard 4:3 display, people will look tall and skinny as if they have been
on a crash diet. The setup options of DVD players allow the viewer to indicate
whether they have a 16:9 or 4:3 TV. In the case of a 4:3 TV, a second option
lets the viewer indicate a preference for how the player will reformat
anamorphic video. The two options are detailed below.
For automatic letterbox mode, the player generates black bars at the top and
the bottom of the picture (60 lines each for NTSC, 72 for PAL). This leaves 3/4
of the height remaining, creating a shorter but wider rectangle (1.78:1). In
order to fit this shorter rectangle, the anamorphic picture is squeezed
vertically using a letterbox filter that combines every 4 lines into 3,
reducing the vertical resolution from 480 scan lines to 360. (If the video was
already letterboxed to fit the 1.78 aspect, then the mattes generated by the
player will extend the mattes in the video.) The vertical squeezing exactly
compensates for the original horizontal squeezing so that the movie is shown in
its full width. Some players have better letterbox filters than others, using
weighted averaging to combine lines (scaling 4 lines into 3 or merging the
boundary lines) rather than simply dropping one out of every four lines.
Widescreen video can be letterboxed to 4:3 on expensive studio equipment before
it's stored on the disc, or it can be stored in anamorphic form and letterboxed
to 4:3 in the player. If you compare the two, the letterbox mattes will be
identical but the picture quality of the studio version may be slightly
better.
For automatic pan & scan mode, the anamorphic video is unsqueezed to 16:9
and the sides are cropped off so that a portion of the image is shown at full
height on a 4:3 screen by following a center of interest offset that's
encoded in the video stream according to the preferences of the people who
transferred the film to video. The pan & scan "window" is 75% of the full
width, which reduces the horizontal pixels from 720 to 540. The pan & scan
window can only travel laterally. This does not duplicate a true pan & scan
process in which the window can also travel up and down and zoom in and out.
Auto pan & scan has three strikes against it: 1) it doesn't provide the same
artistic control as studio pan & scan, 2) there is a loss of detail when the
picture is scaled up, and 3) equipment for recording picture shift information
is not widely available. Therefore, no anamorphic movies have been released with
auto pan & scan enabled, although a few discs use the pan & scan feature
in menus so that the same menu video can be used in both widescreen and 4:3
mode. In order to present a quality full-screen picture to the vast majority of
TV viewers, yet still provide the best experience for widescreen owners, some
DVD producers choose to put two versions on a single disc: 4:3 studio pan &
scan and 16:9 anamorphic.
Playback of widescreen material can be restricted by the producer of the
disc. Programs can be marked for the following display modes:
- 4:3 full
frame
- 4:3 LB (for sending letterbox expand signal to widescreen TV)
-
16:9 LB only (player not allowed to pan & scan on 4:3 TV)
- 16:9 PS only
(player not allowed to letterbox on 4:3 TV)
- 16:9 LB or PS (viewer can
select pan & scan or letterbox on 4:3 TV)
You can usually tell if a disc contains anamorphic video if the packaging
says "enhanced for 16:9 widescreen" or something similar. If all it says is
"widescreen," it may be letterboxed to 4:3, not 16:9. The Laserviews Web site has a list of
anamorphic DVD titles.
Additional explanations of how anamorphic video works can be found at Greg
Lovern's What's an
Anamorphic DVD? page, Bill Hunt's Ultimate Guide to
Anamorphic Widescreen DVD, David Lockwood's What
Shape Image?, and Dan Ramer's What
the Heck Is Anamorphic?. There are excellent animated illustrations at DVD Web (requires Flash). More
information can be found at the Anamorphic
Widescreen Support Page. See 1.38 for further
discussion of letterboxing.
Anamorphosis causes no problems with line doublers and other video scalers,
which simply duplicate the scan lines before they are stretched out by the
widescreen display.
For anamorphic video, the pixels are fatter. Different pixel aspect ratios
(none of them square) are used for each aspect ratio and resolution. 720-pixel
and 704-pixel sizes have the same aspect ratio because the first includes
overscan. Note that "conventional" values of 1.0950 and 0.9157 are for
height/width (and are tweaked to match scanning rates). The table below uses
less-confusing width/height values (y/x * h/w).
720x480 720x576
704x480 704x576 352x480 352x576
4:3 0.909 1.091 1.818 2.182
16:9 1.212 1.455 2.424 2.909
There are two home-entertainment flavors of DVD: DVD-Video and DVD-Audio.
Each supports high-definition multichannel audio. DVD-Audio includes
higher-quality PCM audio.
LPCM is mandatory, with up to 6 channels at sample rates of 48/96/192 kHz
(also 44.1/88.2/176.4 kHz) and sample sizes of 16/20/24 bits. This allows
theoretical frequency response of up to 96 kHz and dynamic range of up to 144
dB. Multichannel PCM is downmixable by the player, although at 192 and 176.4 kHz
only two channels are available. Sampling rates and sizes can vary for different
channels by using a predefined set of groups. The maximum data rate is 9.6
Mbps.
The WG4 decided to include lossless compression (it's about time!), and on
August 5, 1998 approved Meridian's MLP (Meridian Lossless
Packing) scheme, already licensed by Dolby. MLP removes redundancy from the
signal to achieve a compression ratio of about 2:1 while allowing the PCM signal
to be completely recreated by the MLP decoder (required in all DVD-Audio
players). MLP allows playing times of about 74 to 135 minutes of 6-channel
96kHz/24-bit audio on a single layer (compared to 45 minutes without packing).
Two-channel 192kHz/24-bit playing times are about 120 to 140 minutes (compared
to 67 minutes without packing).
Other audio formats of DVD-Video (Dolby Digital, MPEG audio, and DTS,
described below) are optional on DVD-Audio discs, although Dolby Digital is
required for audio content that has associated video. A subset of DVD-Video
features (no angles, no seamless branching, etc.) is allowed. It's expected that
shortly after DVD-Audio players appear, new universal DVD players will also
support all DVD-Audio features.
DVD-Audio includes specialized downmixing features for PCM channels. Unlike
DVD-Video, where the decoder controls mixing from 6 channels down to 2,
DVD-Audio includes coefficent tables to control mixdown and avoid volume buildup
from channel aggregation. Up to 16 tables can be defined by each Audio Title Set
(album), and each track can be identified with a table. Coefficients range from
0dB to 60dB. This feature goes by the horribly contrived name of SMART
(system-managed audio resource technique). (Dolby Digital, supported in both
DVD-Audio and DVD-Video, also includes downmixing information that can be set at
encode time.)
DVD-Audio allows at least 16 still graphics per track (more will fit in the
2MB buffer if they are heavily compressed), with a set of limited transitions.
On-screen displays can be used for synchronized lyrics and navigation menus. A
special simplified navigation mode can be used on players without a video
display.
Sony and Philips are promoting SACD, a competing DVD-based format using
Direct Stream Digital (DSD) encoding with sampling rates of up to 100 kHz. DSD
is based on the pulse-density modulation (PDM) technique that uses single bits
to represent the incremental rise or fall of the audio waveform. This supposedly
improves quality by removing the brick wall filters required for PCM encoding.
It also makes downsampling more accurate and efficient. DSD provides frequency
response from DC to over 100 kHz with a dynamic range of over 120 dB. DSD
includes a lossless encoding technique that produces approximately 2:1 data
reduction by predicting each sample and then run-length encoding the error
signal. Maximum data rate is 2.8 Mbps.
SACD includes a physical watermarking feature. Pit signal processing (PSP)
modulates the width of pits on the disc to store a digital watermark (data is
stored in the pit length). The optical pickup must contain additional circuitry
to read the PSP watermark, which is then compared to information on the disc to
make sure it's legitimate. Because of the requirement for new watermarking
circuitry, SACD discs are not playable in existing DVD-ROM drives.
SACD includes text and still graphics, but no video. Sony says the format is
aimed at audiophiles and is not intended to replace the audio CD format. A
special dual-layer format that would allow SACDs to play in existing compact
disc players was originally planned, but was dropped in 1999 because of
technical problems. It may be revived when yields are high enough that it no
longer costs more to make a hybrid SACD disc than to press both an SACD DVD and
a CD. See 1.12 for
player info.
See E-Town's two-part DVD-Audio vs.
SACD article for more on DVD-Audio and SACD.
The following details are for audio tracks on DVD-Video. Some DVD
manufacturers such as Pioneer are developing audio-only players using the
DVD-Video format. Some DVD-Video discs contain mostly audio with only video
still frames.
A DVD-Video disc can have up to 8 audio tracks (streams). Each track can be
in one of three formats:
- Dolby Digital (formerly AC-3): 1 to 5.1 channels
- MPEG-2 audio: 1 to 5.1 or 7.1 channels
- PCM: 1 to 8 channels.
Two additional optional formats are provided: DTS and SDDS. Both require
external decoders and are not supported by all players.
The ".1" refers to a low-frequency effects (LFE) channel that connects to a
subwoofer. This channel carries an emphasized bass audio signal.
Linear PCM is uncompressed (lossless) digital audio, the
same format used on CDs and most studio masters. It can be sampled at 48 or 96
kHz with 16, 20, or 24 bits/sample. (Audio CD is limited to 44.1 kHz at 16
bits.) There can be from 1 to 8 channels. The maximum bit rate is 6.144 Mbps,
which limits sample rates and bit sizes when there are 5 or more channels. It's
generally felt that the 96 dB dynamic range of 16 bits or even the 120 dB range
of 20 bits combined with a frequency response of up to 22,000 Hz from 48 kHz
sampling is adequate for high-fidelity sound reproduction. However, additional
bits and higher sampling rates are useful in studio work, noise shaping,
advanced digital processing, and three-dimensional sound field reproduction. DVD
players are required to support all the variations of LPCM, but some of them may
subsample 96 kHz down to 48 kHz, and some may not use all 20 or 24 bits. The
signal provided on the digital output for external digital-to-analog converters
may be limited to less than 96 kHz and less than 24 bits.
Dolby Digital is multi-channel digital audio, using lossy
AC-3 coding technology from original PCM with a sample rate of 48 kHz at up to
24 bits. The bitrate is 64 kbps to 448 kbps, with 384 or 448 being the normal
rate for 5.1 channels and 192 being the typical rate for stereo (with or without
surround encoding). (Most Dolby Digital decoders support up to 640 kbps.) The
channel combinations are (front/surround): 1/0, 1+1/0 (dual mono), 2/0, 3/0,
2/1, 3/1, 2/2, and 3/2. The LFE channel is optional with all 8 combinations. For
details see ATSC document A/52 <http://www.atsc.org/>. Dolby Digital is the
format used for audio tracks on almost all DVDs.
MPEG audio is multi-channel digital audio, using lossy
compression from original PCM format with sample rate of 48 kHz at 16 or 20
bits. Both MPEG-1 and MPEG-2 formats are supported. The variable bit rate is 32
kbps to 912 kbps, with 384 being the normal average rate. MPEG-1 is limited to
384 kbps. Channel combinations are (front/surround): 1/0, 2/0, 2/1, 2/2, 3/0,
3/1, 3/2, and 5/2. The LFE channel is optional with all combinations. The 7.1
channel format adds left-center and right-center channels, but will probably be
rare for home use. MPEG-2 surround channels are in an extension stream matrixed
onto the MPEG-1 stereo channels, which makes MPEG-2 audio backwards compatible
with MPEG-1 hardware (an MPEG-1 system will only see the two stereo channels.)
MPEG Layer III (MP3) and MPEG-2 AAC (aka NBC or unmatrix) are not supported by
the DVD-Video standard.
DTS (Digital Theater Systems) Digital Surround is an
optional multi-channel (5.1) digital audio format, using lossy compression from
PCM at 48 kHz at up to 24 bits. The data rate is from 64 kbps to 1536 kbps, with
typical rates of 768 and 1536 for 5.1 channels and 384 or 768 for 2 channels.
(The DTS Coherent Acoustics format supports up to 4096 kbps variable data rate
for lossless compression, but this isn't supported by DVD. DVD also does not
allow sampling rates other than 48 kHz.). Channel combinations are
(front/surround): 1/0, 2/0, 3/0, 2/1, 2/2, 3/2. The LFE channel is optional with
all combinations. DTS ES support 6.1 channels in two ways: 1) a Dolby Surround
EX compatible matrixed rear center channel, 2) a discrete 7th channel. DTS also
has a 7.1-channel mode (8 discrete channels), but no DVDs have used it yet. The
7-channel and 8-channel modes require a new decoder. The DVD standard includes
an audio stream format reserved for DTS, but many older players ignore it. The
DTS format used on DVDs is different from the one used in theaters (Audio Processing Technology's apt-X, an ADPCM
coder, not a psychoacoustic coder). All DVD players can play DTS audio CDs,
since the standard PCM stream holds the DTS code. See 1.32 for general DTS
information. For more info visit <http://www.dtstech.com/> and read Adam
Barratt's article for
Movie Sound Page.
SDDS (Sony Dynamic Digital Sound) is an optional
multi-channel (5.1 or 7.1) digital audio format, compressed from PCM at 48 kHz.
The data rate can go up to 1280 kbps. SDDS is a theatrical film soundtrack
format based on the ATRAC compression format that is also used by Minidisc. Sony
has not announced any plans to support SDDS on DVD.
THX (Tomlinson Holman Experiment) is not an audio format.
It's a certification and quality control program that applies to sound systems
and acoustics in theaters, home equipment, and digital mastering processes. The
LucasFilm THX Digital Mastering program uses a patented process to track video
quality through the multiple video generations needed to make a final format
disc or tape, setup of video monitors to ensure that the filmmaker is seeing a
precise rendition of what is on tape before approval of the master, and other
steps along the way. THX-certified "4.0" amplifiers enhance Dolby Pro Logic:
crossover sends bass from front channels to subwoofer; re-equalization on front
channels (compensates for high-frequency boost in theater mix designed for
speakers behind the screen); timbre matching on rear channels; decorrelation of
rear channels; bass curve that emphasizes low frequencies. THX-certified "5.1"
amplifiers enhance Dolby Digital and improve on 4.0: rear speakers are now full
range, so crossover sends bass from both front and rear to subwoofer;
decorrelation is turned on automatically when rear channels have the same audio,
but not during split-surround effects, which don't need to be decorrelated. More
info at Home
THX Program Overview.
Discs containing 525/60 video (NTSC) must use PCM or Dolby Digital on at
least one track. Discs containing 625/50 video (PAL/SECAM) must use PCM or MPEG
audio or Dolby Digital on at least one track. Additional tracks may be in any
format. A few first-generation players, such as those made by Matsushita, can't
output MPEG-2 audio to external decoders.
The original spec required either MPEG audio or PCM on 625/50 discs. There
was a brief scuffle led by Philips when early discs came out with only
two-channel MPEG and multichannel Dolby Digital, but the DVD Forum clarified in
May 1997 that only stereo MPEG audio was mandatory for 625/50 discs. In December
1997 the lack of MPEG-2 encoders (and decoders) was a big enough problem that
the spec was revised to allow Dolby Digital as the only audio track on 625/50
discs.
Because of the 4% speedup from 24 fps film to 25 fps PAL display, the audio
must be adjusted to match. Unless the audio is digitally processed to shift the
pitch back to normal it will be slightly high (about one half of a
semitone).
For stereo output (analog or digital), all players have a built-in 2-channel
Dolby Digital decoder that downmixes from 5.1 channels (if present on the disc)
to Dolby Surround stereo (i.e., 5 channels are phase matrixed into 2 channels to
be decoded to 4 by an external Dolby Pro Logic processor). PAL players also have
an MPEG or MPEG-2 decoder. Both Dolby Digital and MPEG-2 support 2-channel Dolby
Surround as the source in cases where the disc producer can't or doesn't want to
remix the original onto discrete channels. This means that a DVD labeled as
having Dolby Digital sound may only use the L/R channels for surround or "plain"
stereo. Even movies with old monophonic soundtracks may use Dolby Digital -- but
only 1 or 2 channels. Sony players can optionally downmix to non-surround
stereo. If surround audio is important to you, you will hear significantly
better results from multichannel discs if you have a Dolby Digital system.
The new Dolby Digital Surround EX (DD-SEX?) format, which adds a rear center
channel, is compatible with DVD discs and players, and with existing Dolby
Digital decoders. The new DTS Digital Surround ES (DTS-ES) format, which
likewise adds a rear center channel, works fine with existing DTS decoders and
with DTS-compatible DVD players. However, for full use of both new formats you
need a new decoder to extract the rear center channel, which is phase matrixed
into the two standard rear channels in the same way Dolby Surround is matrixed
into standard stereo channels. Without a new decoder, you'll get the same
5.1-channel audio you get now. Because the additional rear channel isn't a
full-bandwidth discrete channel, it's appropriate to call the new formats
"5.2-channel" digital surround.
The Dolby Digital downmix process does not usually include the LFE channel
and may compress the dynamic range in order to improve dialog audibility and
keep the sound from becoming "muddy" on average home audio systems. This can
result in reduced sound quality on high-end audio systems. The dynamic range
compression (DRC) feature, often called midnight mode, reduces the
difference between loud and soft sounds so that you can turn the volume down to
avoid disturbing others yet still hear the detail of quiet passages. Some
players have the option to turn off DRC. The downmix is auditioned when the disc
is prepared, and if the result is not acceptable the audio may be tweaked or a
separate L/R Dolby Surround track may be added. Experience has shown that minor
tweaking is sometimes required to make the dialog more audible within the
limited dynamic range of a home stereo system, but that a separate track is not
usually necessary.
Dolby Digital also includes a feature called dialog normalization,
which could more accurately be called volume standardization. DN is designed to
keep the sound level the same when switching between different sources. This
will become more important as additional Dolby Digital sources (digital
satellite, DTV, etc) become common. Each Dolby Digital track contains loudness
information so that the receiver can automatically adjust the volume, turning it
down, for example, on a loud commercial. (Of course the commercial makers can
cheat and set an artificially low DN level, causing your receiver to turn up the
volume during the commercial!) Turning DN on or off on your receiver has no
effect on dynamic range or sound quality, its effect is no different than
turning the volume control up or down.
All five DVD-Video audio formats support karaoke mode, which has two channels
for stereo (L and R) plus an optional guide melody channel (M) and two optional
vocal channels (V1 and V2).
A DVD-5 with only one surround stereo audio stream (at 192 kbps) can hold
over 55 hours of audio. A DVD-18 can hold over 200 hours.
Many people complain that the audio level from DVD players is too low. In
truth the audio level is too high on everything else. Movie soundtracks are
extremely dynamic, ranging from near silence to intense explosions. In order to
support an increased dynamic range and hit peaks (near the 2V RMS limit) without
distortion, the average sound volume must be lower. This is why the line level
from DVD players is lower than from almost all other sources. So far, unlike on
CDs and LDs, the level is much more consistent between discs. If the change in
volume when switching between DVD and other audio sources is annoying, you can
adjust the output signal level on some players, or the input signal level on
some receivers, but other than that, there's not much you can do.
For more information about multichannel surround sound, see Bobby Owsinski's
FAQ at <www.surroundassociates.com/safaq.html>.
DVD-Video players (and software DVD-Video navigators) support a command set
that provides rudimentary interactivity. The main feature is menus, which are
present on almost all discs to allow content selection and feature control. Each
menu has a still-frame graphic and up to 36 highlightable, rectangular "buttons"
(only 12 if widescreen, letterbox, and pan & scan modes are used). Remote
control units have four arrow keys for selecting onscreen buttons, plus numeric
keys, select key, menu key, and return key. Additional remote functions may
include freeze, step, slow, fast, scan, next, previous, audio select, subtitle
select, camera angle select, play mode select, search to program, search to part
of title (chapter), search to time, and search to camera angle. Any of these
features can be disabled by the producer of the disc.
Additional features of the command set include simple math (add, subtract,
multiply, divide, modulo, random), bitwise and, bitwise or, bitwise xor, plus
comparisons (equal, greater than, etc.), and register loading, moving, and
swapping. There are 24 system registers for information such as language code,
audio and subpicture settings, and parental level. There are 16 general
registers for command use. A countdown timer is also provided. Commands can
branch or jump to other commands. Commands can also control player settings,
jump to different parts of the disc, and control presentation of audio, video,
subpicture, camera angles, etc.
DVD-V content is broken into "titles" (movies or albums), and "parts of
titles" (chapters or songs). Titles are made up of "cells" linked together by
one or more "program chains" (PGC). A PGC can be on of three types: sequential
play, random play (may repeat), or shuffle play (random order but no repeats).
Individual cells may be used by more than one PGC, which is how parental
management and seamless branching are accomplished: different PGCs define
different sequences through mostly the same material.
Additional material for camera angles and seamless branching is interleaved
together in small chunks. The player jumps from chunk to chunk, skipping over
unused angles or branches, to stitch together the seamless video. Since angles
are stored separately, they have no direct effect on the bitrate but they do
affect the playing time. Adding 1 camera angle for a program roughly doubles the
amount of space needed (and cuts the playing time in half). Examples of
branching (seamless and non-seamless) include Kalifornia, Dark Star, and
Stargate SE.
There are basically two ways to display video: interlaced scan or
progressive scan. Progressive scan, used in computer monitors and digital
television, displays all the horizontal lines of a picture at one time, as a
single frame. Interlaced scan, used in standard television formats NTSC,
PAL, and SECAM, displays only half of the horizontal lines at a time (the first
field, containing the odd-numbered lines, is displayed, followed by the
second field, containing the even-numbered lines). Interlacing relies on the
persistence of vision characteristic of our eyes (which may only be
psychological, not physical), as well as the phosphor persistence of the TV tube
to blur the fields together into a seemingly single picture. The advantage of
interlaced video is that a high refresh rate (50 or 60 Hz) can be achieved with
only half the amount of data. The disadvantage is that the horizontal resolution
is essentially cut in half because the video is often filtered to avoid flicker
and other artifacts.
It may help to understand the difference by considering how the source images
are captured. A film camera shoots 24 frames per second, while a video camera
alternately scans fields of odd and even lines in 1/60 of a second intervals.
(Unlike projected film, which shows the entire frame in an instant, most
progressive-scan displays trace a series of lines from top to bottom, but the
end result is about the same.)
DVD is specifically designed to be displayed on interlaced-scan displays,
which covers 99.9% of the 1 billion TVs worldwide. However, most DVD content
comes from film, which is inherently progressive. To make film content work in
interlaced form, the video from each film frame is split into two video fields
—240 lines in one field, and 240 lines in the other— and encoded as separate
fields in the MPEG-2 stream. Another complication is that film runs at 24
frames/second, while TV runs at 30 frames (60 fields) per second for NTSC or 25
frames (50 fields) per second for PAL and SECAM. For PAL/SECAM display, the
simple solution is to show the film frames at 25/second, which is a 4% speedup,
and speed up the audio to match. For NTSC display, the solution is to spread 24
frames across 60 fields by alternating the display of the first film frame for 2
video fields and the next film frame for 3 video fields. This is called 2-3
pulldown. The sequence works as shown below, where A-D represent film frames;
A1, A2, B1, etc. represent the separation of each film frame into two video
fields; and 1-5 represent the final video frames.
Film frames: | A | B | C | D |
Video fields: |A1 A2|B1 B2|B1 C2|C1 D2|D1 D2|
Video frames: | 1 | 2 | 3 | 4 | 5 |
For MPEG-2 encoding, repeated fields (B1 and D2) are not actually stored
twice. Instead, a flag is set to tell the decoder to repeat the field. (The
apparently inverted order of C2-C1 and D2-D1 are because of the
requirement that top and bottom fields alternate.) MPEG-2 also has a flag to
indicate when a frame is progressive (that the two fields come from the same
instant in time). For film content, the progressive_frame flag should be true
for every frame. See 3.4 for more MPEG-2
details.
As you can see, there are a couple of problems: 1) some film frames are shown
for a longer period of time than others, causing judder, or jerkiness,
that shows up especially in smooth pans; and 2) if you freeze the video on the
third or fourth video frame when there is motion in the picture you
will see two separate images combined in a flickering mess. Most DVD
players avoid the second problem, although some allow you to freeze on
flicker-frames. (This is what the frame/field still option in the player's setup
menu refers to.)
Most DVD players are hooked up to interlaced TVs, so there's not much that
can be done about artifacts from film conversion. However, see 1.40 for information
about progressive DVD players.
When films are transferred to video in preparation for DVD encoding, they are
commonly run through digital processes that attempt to clean up the picture.
These processes include noise reduction (DVNR) and image enhancement.
Enhancement increases contrast (similar to the effect of the "sharpen" or
"unsharp mask" filters in PhotoShop), but can tend to overdo areas of transition
between light and dark or different colors, causing a "chiseled" look or a
ringing effect like the haloes you see around streetlights when driving
in the rain.
Video noise reduction is a good thing, when done well, since it can remove
scratches, spots, and other defects from the original film. Enhancement, which
is rarely done well, is a bad thing. The video may look sharper and clearer to
the casual observer, but fine tonal details of the original picture are altered
and lost.
If your humble FAQ author and other long-time developers of laserdisc had
prevailed, all DVD players would support barcodes. This would have made for
really cool printed supplements and educational discs. But the rejection of our
recommendations after an all-star meeting in August 1995 is another story for
another day.
So the answer is "mostly no." A few industrial players, the Pioneer LD-V7200,
Pioneer LD-V7400, and
Philips ProDVD-170 support
barcodes, including compatibility with the LaserBarCode standard. The DVD must
be authored with one_sequential_PGC titles in order for timecode search to work.
More info can be found in the Pioneer technical
manuals.
Yes, if your computer has the right stuff. The computer operating system or
playback software must support regional codes and be licensed to descramble
copy-protected movies. If the computer has TV video out, it must support
Macrovision in order to play copy-protected movies. You may also need software
that can read the MicroUDF file system format used by DVDs. You don't need
special drivers for Windows, since the existing CD-ROM drivers work fine with
DVD-ROM drives. In addition to a DVD-ROM drive you must have extra hardware to
decode MPEG-2 video and Dolby Digital or MPEG-2 audio, or your computer must be
fast enough to handle software decoding. Good-quality software-only playback
requires a 350-MHz Pentium II or a Mac G4. Less than 10% of new computers with
DVD-ROM drives include decoder hardware, since software decoding is now possible
on even the cheapest new models. Hardware upgrade kits can be purchased for
existing computers (usually minimum 133 MHz Pentium or G3), starting at $150.
See <www.brouhaha.com/~eric/video/dvd>
for a list of drives and upgrade kits.
If you're having problems playing movies on your PC, see section 4.6.
Certain MPEG decoding tasks such as motion compensation and IDCT (inverse
discrete cosine transform) can be performed by additional circuitry on a video
graphics card, improving the performance of software decoders. This is called
hardware decode acceleration or hardware motion comp. All modern graphics cards
also provide hardware colorspace conversion (YCbCr to RGB) and videoport
overlay.
Microsoft Windows 98 and Windows 2000 includes DirectShow, which
provides standardized support for DVD-Video and MPEG-2 playback. DirectShow can
also be installed in Windows 95 (it's available for download). DirectShow
creates a framework for DVD applications, but a third-party hardware or
software decoder is required (see below). Windows NT 4.0 supports DVD-ROM drives
for data, but has very little support for playing DVD-Video discs. Margi
DVD-To-Go, Sigma Designs Hollywood Plus, and the related Creative Labs Dxr3 are
among the few hardware decoders that work in NT 4.0. InterVideo WinDVD software
works in NT 4.0 (Mediamatics DVD Express and MGI SoftDVD Max also work in NT
4.0, but they aren't available retail.) Windows 2000 uses essentially the same
WDM drivers and DirectShow software as Windows 98, so it fully supports movie
playback and DVD applications, including WebDVD. Internet Explorer 5.0 includes
version 6.1 of Windows
Media Player that enables scriptable DVD playback in an HTML page. Windows
98 and newer can read UDF discs. Adaptec
provides a free filesystem driver, UDF Reader, for Windows 95/98/NT. Software Architects sells Read DVD
for Windows 95.
Apple QuickTime 4 is partially
ready for DVD-Video and MPEG-2 but does not yet have full decoding or DVD-Video
playback support in place. Mac OS 8.1 or newer can read UDF discs. Adaptec provides a free utility, UDF
Volume Access, that enables Mac OS 7.6 and newer to read UDF discs. Software Architects sells UDF reading
software for Mac OS called DVD-RAM TuneUp.
Note: The QuickTime MPEG Extension for Mac
OS is for MPEG-1 only and does not play MPEG-2 DVD-Video.
Some DVD-ROMs and a few DVD-Videos use video encoded using MPEG-1 instead of
MPEG-2. Most recent computers have MPEG-1 hardware built in or are able to
decode MPEG-1 with software.
DVD player applications (using either software or hardware decoding) are
virtual DVD players. They support most DVD-Video features (menus, subpictures,
etc.) and emulate the functionality of a DVD-Video player remote control. Many
player applications include additional features such as bookmarks, chapter
lists, and subtitle language lists.
Software decoders and DVD player applications for Microsoft Windows PCs:
- ATI: special version of CineMaster
software for certain ATI graphics cards
- ASUS: ASUSDVD (InterVideo WinDVD
software)
- Creative Technology:
SoftPC-DVD
- CyberLink: PowerDVD
(DirectShow; NT 4.0 and Win2000; available for purchase)
- ELSA: ELSAMovie, German only
- InterVideo: WinDVD
(DirectShow; NT 4.0 and Win2000; available for purchase)
- Matrox: special version of CineMaster
software for certain Matrox graphics cards
- Mediamatics: DVD Express
(DirectShow; OEM only)
- MGI: SoftDVD MAX (DirectShow;
available for purchase) (formerly from
Zoran)
- NEC (NEC PCs only)
- Odyssey: Odyssey DVD Player
(available for purchase)
- Ravisent (formerly Quadrant
International): Software CineMaster (DirectShow; Win 2000; OEM only)
- Varo Vision: VaroDVD
- Xing DVDPlayer is no longer available since the company was
purchased by Real Networks
Software decoders need at least a 350 MHz Pentium II and a DVD-ROM drive with
bus mastering DMA to play without dropped frames. Anything slower than a 400 MHz
Pentium III will benefit quite a bit from hardware decode acceleration in the
graphics card. An AGP graphics card (rather than PCI) also improves the
performance of software decoders.
Hardware decoder cards and DVD-ROM upgrade kits for Microsoft Windows
PCs:
- Creative
Technology:
PC-DVD Encore Dxr3, Sigma EM8300 chip (no DirectShow
yet)
PC-DVD Encore Dxr2, C-Cube chip (DirectShow, Win2000)
- Digital Connection:
3DFusion, Mpact2 chip (DirectShow)
- Digital Voodoo: D1
Desktop 64, Digital Voodoo chip (professional, QuickTime)
- E4 (Elecede): Cool DVD, C-Cube
chip (E4 has gone out of business)
- IBM: ThinkPad
laptops, IBM chip (DirectShow)
- LeadTek: WinFast 3D S800,
Mpact2 chip (DirectShow)
- Luxsonor: decoders in Dell PCs, C-Cube chip (DirectShow)
- Margi: DVD-to-Go, ZV PC card
for laptops (DirectShow, Win2000)
- Ravisent: Hardware
Cinemaster, C-Cube chip (DirectShow)
- Philips Electronics: PCDV632,
PCVD104 (K series come with Sigma Hollywood card, R
series come with software decoder) (DirectShow)
- Samsung:
Revolution, Samsung SD 606 6x, Sigma Hollywood Plus card
(DirectShow)
- Sigma Designs: Hollywood
series, Sigma EM8300 chip (no DirectShow yet)
- STB: DVD Theater, Mpact2 chip
((DirectShow)
- Stradis: Stradis Professional
MPEG-2 Decoder, IBM chip (professional, no DirectShow)
- Toshiba: Tecra laptops,
C-Cube chip (DirectShow)
- Vela Research: CineView Pro
(professional, no DirectShow)
All but the Sigma Designs decoder (including Creative Dxr3) have WDM drivers
for DirectShow. The Sigma Designs decoder card is used in hardware upgrade kits
from Hitachi, HiVal, Panasonic, Phillips,
Sony, Toshiba, and VideoLogic. The advantage of hardware decoders is that they
don't eat up CPU processing power, and they often produce better quality video
than software decoders. The Chromatic Mpact2 chip does 3-field analysis to
produce exceptional progressive-scan video from DVDs (unfortunately, Chromatic
was bought by ATI and the chip is no longer supported — but see Tony Lai's
Mpact2 FAQ at pegasus.ign.com.au/.)
Hardware decoders use video overlay to insert the video into the computer
display. Some use analog overlay, which takes the analog VGA signal output from
the graphics card and keys in the video, while others use video port extension
(VPE), a direct digital connection to the graphics adapter via a cable inside
the computer. Analog overlay may degrade the quality of the VGA signal. See 4.4 for more overlay
info.
Macintosh G4's and some iMacs come standard with DVD-ROM or DVD-RAM drives.
They use the Velocity Engine (AltiVec) portion of the PowerPC chip for video and
audio decoding. Unfortunately, there are numerous problems with Apple's software
decoding. Apple released five software updates in the first four months. Check
MacFixit and MacInTouch for the latest info. A few
models of the iMac, PowerBook, and G3 lines can be ordered with DVD-ROM drives
and hardware decoders. DVD-ROM upgrade kits and decoder cards for Macintoshes
are made by E4 (Elecede) (Cool DVD,
C-Cube chip) [E4 has gone out of business], EZQuest (BOA Mac DVD), Fantom Drives (DVD Home Theater
kit: DVD-ROM or DVD-RAM drive with Wired MPEG-2 card), and Wired (Wired 4DVD, Sigma EM8300 chip
[same card as Hollywood plus]; MasonX [can't play encrypted movies];
DVD-To-Go [out of production]; Wired has been acquired by Media100). There's a beta version of a
shareware DVD software
player that can play unencrypted movies.
The Sigma Designs NetStream
2000 DVD decoder card will support Linux DVD playback.
Computers have the potential to produce better video than settop DVD-Video
players by using progressive display and higher scan rates, but many current
systems don't look as good as a home player hooked up to a quality TV
If you want to hook a DVD computer to a TV, the decoder card or the VGA card
must have a TV output (composite video or s-video). Video quality is much better
with s-video. Alternatively, you can connect a scan converter to the VGA output.
The quality of the video will depend on the decoder, the TV encoder chip, and
other factors, but will usually be a little inferior to a good consumer DVD
player. The RGB output of the VGA card in computers is at a different frequency
than standard component RGB video, so it can't be directly connected to most RGB
video monitors. If the decoder card or the sound card has Dolby Digital or DTS
output, you can connect to your A/V receiver to get multichannel audio.
A DVD PC connected to a progressive-scan monitor or video projector, instead
of a standard TV, usually looks much better than a consumer player. See 2.9. Also see the Home Theater Computers
forum at AVS.
For remote control of DVD playback on your PC, check out Animax Anir Multimedia Magic, Evation IRMan, InterAct WebRemote, Multimedia Studio Miro
MediaRemote, Packard Bell
RemoteMedia, RealMagic Remote
Control, and X10 MouseRemote. Many
remotes are supported by Visual
Domain's Remote Selector software.
Unlike CD-ROM drives, which took years to move up to 2x, 3x, and faster spin
rates, faster DVD-ROM drives began appearing in the first year. 1x DVD-ROM
drives provide a data transfer rate of 1.321 MB/s (11.08*10^6/8/2^20) with burst
transfer rates of up to 12 MB/s or higher. The data transfer rate from a DVD-ROM
disc at 1x speed is roughly equivalent to a 9x CD-ROM drive (1x CD-ROM data
transfer rate is 150 KB/s, or 0.146 MB/s). DVD physical spin rate is about 3
times faster than CD (that is, 1x DVD spin ~ 3x CD spin), but most DVD-ROM
drives increase motor speed when reading CD-ROMs, achieving 12x or faster
performance. A drive listed as "16x/40x" spins a DVD at 16 times normal,
or a CD at 40 times normal. DVD-ROM drives are available in 2x, 4x, 4.8x, 5x,
6x, 8x, 10x, and 16x speeds, although they usually don't achieve sustained
transfer at their full rating. The "max" in DVD and CD speed ratings means that
the listed speed only applies when reading data at the outer edge of the disc,
which moves faster. The average data rate is lower than the max rate. Most 1x
DVD-ROM drives have a seek time of 85-200 ms and access time of 90-250 ms.
| DVD drive speed |
Data rate |
Equivalent CD rate |
Actual CD speed |
| 1x |
11.08 Mbps (1.32 MB/s) |
9x |
8x-18x |
| 2x |
22.16 Mbps (2.64 MB/s) |
18x |
20x-24x |
| 4x |
44.32 Mbps (5.28 MB/s) |
36x |
24x-32x |
| 5x |
55.40 Mbps (6.60 MB/s) |
45x |
24x-32x |
| 6x |
66.48 Mbps (7.93 MB/s) |
54x |
24x-32x |
| 8x |
88.64 Mbps (10.57 MB/s) |
72x |
32x-40x |
| 10x |
110.80 Mbps (13.21 MB/s) |
90x |
32x-40x |
| 16x |
177.28 Mbps (21.13 MB/s) |
144x |
32x-40x |
The bigger the cache (memory buffer) in a DVD-ROM drive, the faster it can
supply data to the computer. This is useful primarily for data, not video. It
may reduce or eliminate the pause during layer changes, but has no effect on
video quality.
Rewritable DVD drives (see 4.3) write at about
half their advertised speed when the data verification feature is turned on,
which reads each block of data after it is written. Verification is usually on
by default. Turning it off will speed up writing. Whether this endangers your
data is a subject of debate.
In order to maintain constant linear density, typical CD-ROM and DVD-ROM
drives spin the disc more slowly when reading near the outside where there is
more physical surface in each track. (This is CLV, constant linear velocity.)
Some faster drives keep the rotational speed constant and use a buffer to deal
with the differences in data readout speed. (This is CAV, constant angular
velocity.) In CAV drives, the data is read fastest at the outside of the disc,
which is why specifications often list "max speed."
Note: When playing movies, a fast DVD-ROM drive gains you nothing more than
possibly smoother scanning and faster searching. Speeds above 1x do not improve
video quality from DVD-Video discs. Higher speeds only make a difference when
reading computer data, such as when playing a multimedia game or when using a
database.
Connectivity is similar to that of CD-ROM drives: EIDE (ATAPI), SCSI-2, etc.
All DVD-ROM drives have audio connections for playing audio CDs. No DVD-ROM
drives have been announced with DVD audio or video outputs (which would require
internal audio/video decoding hardware). In order to hook a DVD-ROM PC to a
television and a stereo receiver, the decoder card or the video card must have a
TV video output and an audio output. Some cards have SP/DIF outputs to connect
to digital audio receivers. If there's no video output, a TV scan converter can
be connected to the VGA output.
Almost all DVD-Video and DVD-ROM discs use the UDF Bridge format, which is a
combination of the DVD MicroUDF and ISO 9660 file systems. The OSTA UDF file system will eventually replace the
ISO 9660 system originally designed for CD-ROMs, but the bridge format provides
backwards compatibility until more operating systems support UDF.
There are five recordable versions of DVD-ROM: DVD-R/authoring,
DVD-R/general, DVD-RAM, DVD-RW, and DVD+RW. All can read DVD-ROM and DVD-Video
discs, but each uses a different type of disc for recording. DVD-R can record
data once (sequentially only), while DVD-RAM, DVD-RW, and DVD+RW can be
rewritten thousands of times. Final versions of the DVD-R and DVD-RAM version
1.0 specifications were published in August 1997 (see 6.1). DVD-RW 1.0 and
DVD-R 2.0 are being finalized in early 2000. DVD+RW will be available in early
2001. Most recordable media are not currently usable for home video recording
(see 1.14), though
home DVD recorders became available in Japan at the beginning of 2000. The three
erasable formats (DVD-RAM, DVD-RW, and DVD+RW) are essentially in competition
with each other. The market will determine which of them succeed. DVD-RAM has a
head start of more than a year.
Toshiba, Panasonic, and others released combination DVD-ROM/CD-RW drives near
the end of 1999.
Each writable DVD format is covered briefly below. For more on writable DVD,
see Dana Parker's article at <www.emediapro.net/EM1999/parker1.html>.
If you're interested in writable DVD for data storage, visit Steve Rothman's DVD-DATA page
for FAQ and mailing list info.
DVD-R and DVD-RW
DVD-R uses organic dye polymer technology, like CD-R, and is compatible with
most DVD drives and players. First-generation capacity was 3.95 billion bytes,
but was later extended to 4.7 billion bytes. Matching the 4.7G capacity of
DVD-ROM was crucial for desktop DVD-ROM and DVD-Video production. In early 2000,
the format was split into an "authoring" version and a "general" version. The
general version will use a 650nm laser (instead of 635nm) for future ability to
write DVD-RAM.
DVD-RW (formerly DVD-R/W and also briefly known as DVD-ER) is a phase-change
erasable format that became available at the end of 1999. Developed by Pioneer
based on DVD-R, using the similar track pitch, mark length, and rotation
control, DVD-RW will be playable in most DVD drives and players. (Some drives
and players are confused by DVD-RW media's lower reflectivity into thinking it's
a dual-layer disc. Simple firmware upgrades are required to solve the problem.)
DVD-RW uses groove recording with address info on land areas for synchronization
at write time (land data is unnecessary during reading). Capacity is 4.7 billion
bytes. DVD-RW can be rewritten about 1,000 times. DVD-R discs are expected to
last anywhere from 50 to 250 years, about as long as CD-R discs. DVD-RW discs
won't last quite as long. See <www.ee.washington.edu/conselec/CE/kuhn/otherformats/95x9.htm>
and <www.cd-info.com/CDIC/Technology/CD-R/Media/Kodak.html>
for more info. For comparison, magnetic media (tapes and disks) lasts 10 to 30
years, high-quality acid neutral paper can last a hundred years or longer, and
archival-quality microfilm is projected to last 300 years or more. Note that
optical media can become technically obsolete within 20 to 30 years, long before
it physically deteriorates.
Pioneer released 3.95G DVD-R 1.0 drives in October 1997 (about 6 months late)
for $17,000. New 4.7G DVD-R 1.9 drives appeared in limited quantities in May
1999 (about 6 months late) for $5,400. A future version of the drive will
support DVD-R 2.0 media and DVD-RW media. Price for blank DVD-Rs is about $40.
Initial DVD-RW prices will be about the same. Blank media is being made by
Eastman Kodak, Hitachi Maxell, Mitsubishi, Mitsui, Pioneer, Ricoh, Ritek, TDK,
Verbatim, and Victor. Ricoh, Yamaha, Sony, and others will join Pioneer in
making 4.7G DVD-R/RW drives.
In December 1999, Pioneer released DVD-RW home video recorders in Japan. The
unit costs 250,000 yen (about $2,500) and blank discs cost 3,000 yen (about
$30). Since the recorder uses the new DVD-VR (video recording) format, the discs
won't play in existing players (the discs are physically compatible, but
not logically compatible). Recording time varies from 1 hour to 6 hours,
depending on quality. The player is expected to be released in the U.S. and
elsewhere around the middle of 2000. Sharp announced a $2,200 DVD-RW recorder,
and Zenith (LG) announced a $2,000 DVD-RW recorder, both expected near the end
of 2000. DVD video recorders will not copy protected DVD movie discs.
The advantages of DVD-R and DVD-RW drives, which are used primarily for DVD
production, are higher capacity and compatibility with most DVD players and
drives.
The DVD-R 1.0 format is standardized in ECMA-279.
DVD-RAM
DVD-RAM, with an initial storage capacity of 2.58 billion bytes, uses
phase-change (PD) technology with some MO features mixed in. It is not
compatible with most drives and players (because of defect management,
reflectivity differences, and minor format differences). A wobbled groove is
used to provide clocking data, with marks written in both the groove and the
land between grooves. The grooves and pre-embossed sector headers are molded
into the disc during manufacturing. Single-sided DVD-RAM discs come with or
without cartridges. There are two types of cartridges: type 1 is sealed, type 2
allows the disc to be removed. Discs can only be written while in the cartridge.
Double-sided DVD-RAM discs are available in sealed cartridges only. Cartridge
dimensions are 124.6 mm x 135.5 mm x 8.0 mm. DVD-RAM can be rewritten about
100,000 times, and the discs are expected to last at least at least 30
years.
DVD-RAM drives appeared in June 1998 (about 6 months late) for $500 to $800,
with blank discs at about $30 for single-sided and $45 for double-sided. Disc
prices were under $20 by August 1998, and retail drive prices were under $250 by
November 1999. The first DVD-ROM drive to read DVD-RAM discs was released by
Panasonic in 1999 (SR-8583, 5x DVD-ROM, 32x CD). Hitachi's GD-5000 drive,
released in late 1999, also reads DVD-RAM discs. Blank DVD-RAM media is
manufactured by Hitachi Maxell, Eastman Kodak, Mitsubishi, Mitsui, Ritek, and
TDK.
DVD-RAM version 2.0, with a capacity of 4.7 billion bytes per side, was
published in October 1999. The first drives will appear in mid 2000 at about the
same price as current DVD-RAM 1.0 drives. DVD-RAM 2.0 also specifies 8cm discs
and cartridges for portable uses such as digital camcorders. Future DVD-RAM
discs may use a contrast enhancement layer and a thermal buffer layer to achieve
higher density.
Samsung and C-Cube made a technology demonstration (not a product
announcement) in October 1999 of a DVD-RAM video recorder using the new DVD-VR
format (see DVD-R/RW section above for DVD-VR details). Panasonic demonstrated a
$3,000 DVD-RAM video recorder at CES in January 2000, with expected availability
in late 2000. Samsung said its $2,000 DVD-RAM-based recorder would be out around
the same time. Hitachi showed a camcorder that uses the smaller DVD-RAM discs,
to be available for $3,000 in late 2000.
The DVD-RAM 1.0 format is standardized in ECMA-272 and ECMA-273.
DVD+RW
Phase-Change Rewritable DVD is an erasable format announced by Philips, Sony,
Hewlett-Packard and others based on CD-RW technology. It will become available
in early 2001. DVD+RW is not supported by the DVD Forum (even though the DVD+RW
companies are members), but the Forum has no power to set standards. DVD+RW
drives will read DVD-ROMs and CDs, and probably DVD-Rs and DVD-RWs, but will not
read or write DVD-RAM discs. The drives are expected to write CD-Rs and CD-RWs.
DVD+RW discs, which hold 4.7 billion bytes (4.4 gigabytes) per side, should be
readable in about 70% of the existing DVD-Video players and DVD-ROM drives.
DVD+RW backers claimed in 1997 that it would be used only for computer data,
not home video, but this was apparently a smokescreen intended to placate the
DVD Forum and competitors. The original 1.0 format, which held 3 billion bytes
(2.8 gigabytes) per side and was incompatible with all existing players and
drives, was abandoned in late 1999.
The DVD+RW format uses phase-change technology with a high-frequency wobbled
groove that allows it to eliminate linking sectors. This, plus the option of no
defect management, allows DVD+RW discs to be written in a way that should be
compatible with many existing DVD readers. DVD+RW discs can be recorded in
either CLV format for sequential video access (read at CAV speeds by drive) or
CAV format for random access. DVD+RW media can be rewritten about 1,000 times
(down from 100,000 times in the original version), and the discs are expected to
last at least 30 years.
Media will be produced by MCC/Verbatim. Ricoh and Yamaha have also announced
support for the DVD+RW format.
Philips announced a DVD+RW home video recorder, to be available "after mid
2000." [Jim's prediction (Jan 2000): we won't see it until early 2001.] Unlike
the Pioneer DVD-RW recorder, the Philips recorder will use the DVD-Video format,
so discs will play in many existing players.
More DVD+RW information is at <http://www.dvdrw.org/>. The obsolete DVD+RW
1.0 format is standardized in ECMA-274.
Others
Other upcoming potential competitors to recordable DVD include AS-MO
(formerly MO7), which holds 5 to 6 billion bytes, and NEC's Multimedia Video
Disc (MVDisc, formerly MMVF, Multimedia Video File), which holds 5.2 billion
bytes and is targeted at home recording. ASMO are expected to read DVD-ROM but
not DVD-RAM or first-generation DVD+RW. MVDisc is similar to DVD-RW and DVD+RW,
using two bonded 0.6mm phase-change substrates, land and groove recording, and a
640nm laser, but contrary to initial reports, the drives won't be able to read
DVD-ROM or compatible discs.
Most DVD PCs, even those with software decoders, use video overlay hardware
to insert the video directly into the VGA signal. This an efficient way to
handle the very high bandwidth of full-motion video. Some decoder cards, such as
the Creative Labs Encore Dxr series and the Sigma Designs Hollywood series, use
a pass-through cable that overlays the video into the analog VGA signal after it
comes out of the video display card. Video overlay uses a technique called
colorkey to selectively replace a specified pixel color (often magenta or
near-black) with video content. Anywhere a colorkey pixel appears in the
computer graphics video, it's replaced by video from the DVD decoder. This
process occurs "downstream" from the computer's video memory, so if you try to
take a screenshot (which grabs pixels from video RAM), all you get is a solid
square of the colorkey color.
Some decoders write to normal video memory. In this case, utilities such as
Creative Softworx, HyperSnap, and SD Capture can grab still
pictures. Some player applications can also take screenshots.
Almost all movies are encrypted with CSS copy protection (see 1.11). Decryption keys
are stored in the normally inaccessible lead-in area of the disc. If you copy
the contents of an encrypted DVD to a hard drive, the keys will not be copied.
If you try to play the VOB files, the decoder will request the keys from the
DVD-ROM drive and will fail. You may get the message "Cannot play copy-protected
files".
There are thousands of answers to this question, but here are some basic
troubleshooting steps to help you track down problems such as jerky playback,
pauses, error messages, and so on.
- Get updated drivers. Driver bugs are the biggest cause of playback
problems, ranging from freezes to bogus error messages about regions. Go to
the support section on the Web sites of your equipment manufacturers and make
sure you have the latest decoder drivers as well as the latest drivers for
your graphics adapter and DVD-ROM drive.
Apple has released numerous
updates for audio drivers and the DVD player application. Make sure you have
the latest versions. Go to the downloads page and search for DVD.
- Make sure DMA is turned on. For Windows, go into the System Properties
Device Manager, choose CD-ROM, open the CD/DVD driver properties, choose the
Settings tab, and make sure the DMA box is checked. Caution: You may run into problems with an AMD K6 CPU.
Check for a BIOS upgrade and a CD/DVD-ROM driver upgrade from your system
manufacturer before turning DMA on.
- If you get an error about unavailable overlay surface, reduce the display
resolution or number of colors (right-click desktop, choose Settings tab).
- Try turning off programs that are running in the background. (Close or
exit applets in the Windows system tray.)
- If you are using a SCSI DVD-ROM drive, make sure that the it's the first
or last device in the SCSI chain. If it's the last device, make sure it's
terminated.
- Bad video when connecting to a TV could be from too long a cable or from
interference or a ground loop. See 3.2.2.
More information on specific graphics cards and driver updates:
Short answer: usually not.
With a fast enough network (100 Mbps or better, with good performance and low
traffic) and a high-performance server, it's possible to stream DVD-Video from a
server to client stations. If the source on the server is a DVD-ROM drive (or
jukebox), then more than one user simultaneously accessing the same disc will
cause breaks in the video unless the server has a fast DVD-ROM drive and a very
good caching system designed for streaming video.
A big problem is that CSS-encrypted movies (see 1.11) are difficult to
remotely source because of security issues. The CSS license does not allow
decrypted video to be sent over an accessible bus or network, so the decoder has
to be on the remote PC. If the decoder has a secure channel to perform
authentication with the drive on the server, then it's possible to stream
encrypted video over a network to be decrypted and decoded remotely.
An alternative is to decode the video at the server and send it to
individual stations via separate cables (usually RF). The advantage is that
performance is very good, but the disadvantage is that that DVD interactivity is
usually limited, and every viewer connected to a single drive/decoder must watch
the same thing at the same time.
Many companies provide support for streaming MPEG-1 and MPEG-2
video over LANs, but only from files or realtime encoders, not from DVD-Video
discs.
The Internet is a different matter. It takes over a week to
download the contents of a single-layer DVD using a 56k modem. It takes about 7
hours on a T1 line. Cable modems theoretically cut the time down to a few hours,
but if other users in the same neighborhood have cable modems, bandwidth could
drop significantly. [Jim's prediction: the average DVD viewing household won't
have sufficiently fast Internet connections before 2007 at the earliest. Around
that time there will be a new high-definition version of DVD with double the
data rate, which will once again exceed the capacity of the typical Internet
connection.]
CSS (Content Scrambling System) is an encryption and authentication scheme
intended to prevent DVD movies from being digitally copied. See 1.11 for details.
DeCSS refers to the general process of defeating CSS, as well as to DeCSS source
code and programs.
Computer software to decrypt CSS was released to the Internet in October 1999
(see Dana Parker's article at www.emediapro.net/news99/news111.html),
although other "ripping" methods were available before that (see http://www.7thzone.com/, go.to/dvdsoft, and http://www.neophile.net/). The difference
between circumventing CSS encryption with DeCSS and intercepting decrypted,
decompressed video with a DVD ripper is that DeCSS can be considered illegal
under the DMCA and the WIPO treaties. The DeCSS information can be used
to "guess" at master keys, such that a standard PC can generate the entire list
of 400 keys, rendering the key secrecy process useless.
In any case, there's not much appeal to being able to copy a set of movie
files (often without menus and other DVD special features) that would take over
a week to download on a 56K modem and would fill up a 6G hard disk or a dozen
CD-Rs. In March 2000, a DVD redistribution technology called DivX appeared. (Its
creators should be drawn and quartered for the stupid joke name, which has
confused thousands.) DivX is a simple hack of Microsoft's MPEG-4 video codec and
MP3 audio, allowing DeCSSed video to be downloaded and played in Windows Media Player.
In spite of lower data rates (and therefore much lower quality), the time and
effort it takes to find and download the files is not worth the bother for most
movie viewers. The reality is that people ripping and downloading DVDs are doing
it for the challenge, not to avoid buying discs.
The supporters of DeCSS point out that it was only developed to allow DVD
movies to be played on the Linux operating system, which had been excluded from
CSS licensing because of its open-source nature. This is specifically allowed by
DMCA and WIPO laws. What most DeCSS proponents fail to acknowledge (or perhaps
fail to realize) is that the DeCSS.exe program posted on the Internet is a
Windows application that is clearly intended for copying movies. This lack of
differentiation between the DeCSS process in Linux and the DeCSS.exe Windows
application is hurting the cause of DeCSS backers. See OpenDVD.org for more information on
DeCSS.
Worthy of note is that DVD piracy was around long before DeCSS. Serious DVD
pirates can copy the disc bit for bit, including the normally unreadable lead in
(this can be done with a specially modified drive), or copy the video output
from a standard DVD player, or get a copy of the video from another source such
as laserdisc, VHS, or a camcorder smuggled into a theater. It's certainly true
that DVD piracy is a problem, but DeCSS has little to do with it.
Shortly after the appearance of DeCSS, the DVD CCA filed a lawsuit and requested a
temporary injunction in an attempt to prevent Web sites from posting (or even
linking to!) DeCSS information. The request was denied by a California court on
December 29, 1999. On January 14, 2000, the seven top U.S. movie studios
(Disney, MGM, Paramount, Sony [Columbia/TriStar], Time Warner, Twentieth Century
Fox, and Universal), backed by the MPAA,
filed lawsuits in Connecticut and New York in a further attempt to stop the
distribution of DeCSS on Web sites in those states. On January 21, the judge for
the New York suit granted a preliminary
injunction, and on January 24, the judge for the CCA suit in California
reversed his earlier decision and likewise granted a preliminary
injunction. In both cases, the judges ruled that the injunction applied only
to sites with DeCSS information, not to linking sites. (Good thing, since this
FAQ links to DeCSS sites!) The CCA suit is based on misappropriation of trade
secrets (somewhat shaky ground), while the MPAA suits are based on copyright
circumvention. On January 24, 16-year old Jon Johansen, the Norwegian programmer
who first distributed DeCSS, was questioned by local police who raided his house
and confiscated his computer equipment and cell phone. Johansen says the actual
cracking work was done by two anonymous programmers, one German and one Dutch,
who call themselves Masters of Reverse Engineering (MoRE).
This all seems to be a losing battle, since the DeCSS source code
is available on a T-shirt
and was made publicly available by the DVD CCA itself in court records--oops! See Fire, Work
With Me for a facetious look at the broad issue.
A variety of multimedia development/authoring programs can be
extended to play video from a DVD, either as titles and chapters from a
DVD-Video volume, or as MPEG-2 files. In Windows, this is usually done with
ActiveX controls. On the Mac, until DVD-Video support is added to QuickTime, the
options are limited.
DVD-Video and MPEG-2 video can be played back in an HTML page in
Microsoft Internet Explorer using Windows Media Player
(docs on DVD scripting are in the Windows
Media SDK), InterActual PC
Friendly, or SpinWare PortaLink.
Netscape Navigator doesn't work, since it doesn't support ActiveX objects.
MPEG-2 video can be played in PowerPoint, Visual Basic, or other
ActiveX hosts using Windows Media Player. Because of an annoying reliance on IE,
WMP must be embedded into an HTML page, then controlled with the Browser ActiveX
control in order to play DVD-Video. Zuma Digital's ActiveDVD (using the PC Friendly engine),
Daikin's Enhanced DVD
Kit (also using the PC Friendly engine), and Visible Lights' OnStage DVD ActiveX provide ActiveX-based
DVD playback.
A number of Xtras are (or will soon be) available for DVD playback
in Director. Tabuleiro's DirectMediaXtra plays MPEG-2 files (the
older MpegXtra uses MCI, which doesn't work well for MPEG-2 and DVD). LBO's Xtra DVD and Visible Light's OnStage DVD Xtra plays DVD-Video
volumes.
Of course, if you simply treat DVD-ROM as a bigger, faster CD-ROM,
you can create projects using traditional tools (Director, Flash, Toolbook,
HyperCard, VB, HTML, etc.) and traditional media types (CinePak, Sorenson,
Indeo, etc. in QuickTime or AVI format) and they'll work just fine from DVD. You
can even raise the data rate for bigger or better quality video. But it still
won't look as good as MPEG-2.
The DVD-Video and DVD-Audio specifications define how audio and
video data are stored in specialized files. The .IFO (and backup .BUP) files
contain menus and other information about the video and audio. The .VOB files
(for DVD-Video) and .AOB files (for DVD-Audio) are MPEG-2 program streams with
additional packets containing navigation and search information.
Since a .VOB file is just a specialized MPEG-2 file, most MPEG-2
decoders and players can play them. However, any special features such as angles
or branching will cause strange effects. The best way to play a .VOB file is to
use a DVD player application to play the entire volume (or to open the
VIDEO_TS.IFO file), since this will make sure all the DVD-Video features are
used properly.
The DVD Video Recording format will introduce .SOB files
<snigger>.
Most .VOB files won't play when copied to your hard drive. See 4.5.
DVD production has two basic phases: development and
replication. Development is different for DVD-ROM and DVD-Video,
replication is essentially the same for both.
DVD-ROMs can be developed with traditional software development tools such as
Macromedia Director, Asymetrix Toolbook, HyperCard, Quark mTropolis, and C++.
Discs, including DVD-R check discs, can be created with UDF formatting software
(see 5.3). DVD-ROMs
that take advantage of DVD-Video's MPEG-2 video and multichannel Dolby Digital
or MPEG-2 audio require video and audio encoding (see 5.3).
DVD-Video development has three basic parts: encoding,
authoring (design, layout, and testing), and premastering
(formatting a disc image). The entire development process is sometimes referred
to as authoring. Development facilities are provided by many service bureaus
(see 5.5). If you
intend to produce numerous DVD-Video titles (or you want to set up a service
bureau), you may want to invest in encoding and authoring systems (see 5.3 and 5.4).
Replication (including mastering) is usually a separate job done by large
plants that also replicate CDs (see 5.5). DVD replication
equipment typically costs millions of dollars. A variety of machines are used to
create a glass master, create metal stamping masters, stamp substrates in
hydraulic molds, apply reflective layers, bond substrates together, print
labels, and insert discs in packages. Most replication plants provide "one-off"
or "check disc" services, where one to a hundred discs are made for testing
before mass duplication. Unlike DVD-ROM mastering, DVD-Video mastering may
include an additional step for CSS encryption, Macrovision, and regionalization.
There is more information on mastering and replication at Panasonic Disc Services and
Technicolor.
For projects requiring less than 50 copies, it can be cheaper use DVD-R.
Automated machines can feed DVD-R blanks into a recorder, and even print labels
on each disc. This is called duplication, as distinguished from
replication.
Videotape, laserdisc, and CD-ROM can't be compared to DVD in a
straightforward manner. There are basically three stages of costs: production,
pre-mastering (authoring, encoding, and formatting), and
mastering/replication.
DVD video production costs are not much higher than for VHS and similar video
formats unless the extra features of such as multiple sound tracks, camera
angles, seamless branching, etc. are employed.
Authoring and pre-mastering costs are proportionately the most expensive part
of DVD. Video and audio must be encoded, menus and control information have to
be authored and encoded, it all has to be multiplexed into a single data stream,
and finally encoded in low level format. Typical charges for compression are
$60/min for video, $20/min for audio, $6/min for subtitles, plus formatting and
testing at about $30/min. A ballpark cost for producing a Hollywood-quality
two-hour DVD movie with motion menus, multiple audio tracks, subtitles,
trailers, and a few info screens is about $20,000. Alternatively, many
facilities charge for time, at rates of around $400/hour. A simple two-hour
DVD-Video title with menus and various video clips can cost as low as $3,000. If
you want to do it yourself, authoring and encoding systems can be purchased at
prices from $400 to over $2 million. Prices for software and hardware will drop
very rapidly in the next few years to where DVDs can be produced on a desktop
computer system that costs less than $20,000.
Videotapes don't really have a mastering cost, and they run about $2.40 for
replication. CDs cost about $1,000 to master and $0.50 to replicate. Laserdiscs
cost about $3,000 to master and about $8 to replicate. As of the beginning of
2000, DVDs cost about $1000 to master and about $1.60 to replicate. Since DVD
production is based mostly on the same equipment used for CD production,
mastering and replication costs will drop to CD levels. Double-sided or
dual-layer discs cost about $1 more to replicate, since all that's required is
stamping data on the second substrate (and using transparent glue for dual
layers). Double-sided, dual-layer discs (DVD-18s) are more difficult and more
expensive. (See 3.3.1.)
- Adaptec
Toast DVD. DVD
formatting software for Mac OS. Writes to DVD-R and tape. Can create DVD-Video
discs from VOB and IFO files. $200
- GEAR
GEAR Pro DVD. DVD
formatting software for Windows 95/98/NT4. Writes to DVD-R, DVD-RAM,
jukeboxes, and tape, along with general UDF formatting and CD-R/RW burning
features. $700.
- JVC Professional Computer
Products
DVD RomMaker. DVD formatting systems with RAID hardware.
$60,000 to $100,000.
- MTC (Multimedia Technology Center)
ForDVD. DVD formatting software
for Windows. Writes to DVD-R and tape. Can create DVD-Video discs from VOB and
IFO files.
- Philips
DVD-ROM
Disc Builder. DVD formatting software for Windows NT. Writes to tape.
- Prassi
DVD Rep. DVD
formatting software for Windows. Writes to DVD-R, DVD-RAM, and tape.
- Smart Storage
SmartDVD
Maker. DVD formatting software for Windows NT. Writes to DVD-R and tape.
Can create DVD-Video discs from VOB and IFO files. $2500.
- Software
Architects
WriteDVD and WriteUDF. DVD formatting software
for Mac OS and Windows. Writes to DVD-R and DVD-RAM.
- Young Minds
DVD Studio and
MakeDisc for DVD. DVD formatting software for Windows NT and Unix.
Writes to DVD-R.
Features to look for in DVD formatters:
- Support for UDF file system, including MicroUDF for DVD-Video and
DVD-Audio zones.
- Support for UDF bridge format, which stores both UDF and ISO-9660 file
systems on the disc.
- Ability to recognize VIDEO_TS and AUDIO_TS directories (containing IFO,
VOB, and AOB files) and place them contiguously at the physical beginning of
the disc for compatibility with DVD-Video players. Placement of directory
entries in first UDF file descriptor is also needed for compatibility with
certain deficient consumer players.
- Support for long filenames in Windows (Joliet format recommended).
- Full equivalence between UDF and Joliet (ISO-9660) filenames.
(Windows NT 4.0 and Windows 98 read Joliet filenames; Mac OS 8.1+,
Windows 98, and Windows 2000 read UDF filenames. MS-DOS and Windows 95 and
earlier read ISO-9660 filenames. Mac OS 8.0 and earlier read HFS or ISO-9660
filenames.)
- Proper truncation and translation of ISO-9660 filenames to 8.3 format for
discs intended for use with MS-DOS and certain other OSes.
- Support for Mac OS file information within the UDF file system (for use
with Mac OS 8.1 and later).
- Support for Mac OS HFS file system if icons and other file information is
needed for Mac OS versions earlier than 8.1.
- Ability to create a bootable disc using the El Torito specification in the
ISO-9660 sectors.
- Astarte
- M.Pack. MPEG-2 video encoding software for Mac OS. (PixelTools
encoding engine.) $400.
- Brent Beyeler
- bbMPEG. Basic MPEG-2 encoder for Windows. Free.
- Canopus
- Amber MPEG-2 Archiving and Mastering Kit. MPEG-2 hardware
designed for encoding and archiving video onto DVD-RAM discs. VBR and
CBR. In spite of its name, it doesn't actually do any mastering.
(Panasonic MN85560 encoder chip). Windows NT. $2,500.
- Custom Technology
- Cinemacraft. MPEG-2 real-time NTSC video encoding software for
Windows NT.
- Darim
- MPEGator 2. MPEG-2 real-time encoding hardware for Windows and Windows
NT. $1,800.
- Digital Ventures
- DVDComposer. MPEG-2 video encoding system for SGI. VBR and CBR.
(C-Cube chip). $50,000.
- Digital Vision
- BitPack. MPEG-2 video encoding workstation. Extendable to HDTV.
- DVNR system for video pre-processing.
- Digigami
- MegaPeg. MPEG-2 video encoding software for Windows. VBR and CBR.
$500. Also available as Adobe Premiere plug-in for Windows or PowerMac.
$400.
- DreamCom (formerly Gunzameory)
- MPEGRich. Professional MPEG-2 real-time encoding hardware. CBR
and VBR. Windows NT.
- DV Studio
- Apollo Expert. MPEG-2 video encoding (and decoding) hardware for
Windows NT. $2,000.
-
FAST Multimedia
- 601 [six-o-one]. MPEG-2 non-linear editing system with "print to
DVD" option to output MPEG-2 ES or PS.
- Heuris
- MPEG Power Professional and MPEG Power Professional DVD.
MPEG-2 video encoding software for Mac OS and Windows. DVD version includes
VBR encoding. $1,500 and $2,500.
- Cyclone. MPEG-1 and MPEG-2 encoding software designed for OEMs.
Mac OS and Windows NT.
- InnovaCom
- DV5100. MPEG-2 real-time hardware encoding station for Windows
NT.
Ligos
- LSX-MPEG Encoder. MPEG-2 video encoding software. CBR and VBR.
Windows. $150.
- LSX-MPEG Suite. Adobe Premiere plug-in for producing MPEG-1 or
MPEG-2 output. Includes standalone LSX-MPEG player. Windows 9x/NT. $400.
- Media100
- iFinish RealTime MPEG Option. Editing software with MPEG-2 video
encoding add-on. Windows NT. $6,000 to $18,000.
- Microcosmos/Nanocosmos
- MPEG SoftEngine. MPEG-2 video encoding software for Windows,
Solaris, and Linux. $250 to $3500.
- Minerva
- Compressionist 110, 200, and 250. Professional MPEG-2
real-time encoding hardware. CBR and VBR. Mac OS host computer. $70,000. [No
longer available.]
- Publisher 300. Professional MPEG-2 video and MPEG Layer 2 audio
real-time encoding hardware. CBR and VBR. Mac OS. [No longer available.]
- Optibase
- MPEG MovieMaker 200. Professional MPEG-2 video and Dolby Digital audio
real-time encoding hardware for Windows and Windows NT. CBR and VBR. $7,000
to $22,000.
- Philips
- DVS3110. Professional MPEG-2 video encoder for PAL and NTSC. CBR
and VBR.
- PixelTools
- Expert-DVD. MPEG-2 video encoding software. CBR and VBR. Windows.
$2,000.
- Simple-DVD. AVI-to-DVD conversion utility for Windows. $1,5000.
- Snell & Wilcox
- Prefix CPP100, Prefix CPP200, NRS500, Kudos NRS50, and Kudos
NRS30.. Video preprocessors (noise reduction and image enhancement).
- Sonic Solutions
- Sonic DVD Studio. Professional MPEG-2 video encoding hardware.
CBR and VBR. Segment-based reencoding. Mac OS.
- DVD Fusion. Encoding/authoring plug-in for Media 100 and
QuickTime video editing systems. Hardware-accelerated version (velocity
engine) encodes VBR and CBR in real time. Mac OS. $8,000 and $12,000.
- Sony
- DVA-V1100. High-end MPEG-2 video encoding hardware. CBR and VBR.
Windows NT.
- Spruce Technologies
- MPEGXpress 3000. Professional MPEG-2 real-time encoding hardware.
CBR and VBR. Windows NT.
- MPEGXpress 2000 (formerly from CagEnt). Professional MPEG-2
real-time encoding hardware. CBR and VBR. Windows NT.
- Tele-Cine
- Film to video (telecine) transfer services.
- VisionTech
- MVCast. Low-end real-time MPEG-2 video/audio encoding hardware
for Windows NT and Solaris. AVI-to-MPEG-2 conversion. $2000.
- Vitech
- MPEG Toolbox-2. AVI to MPEG-2 VBR/CBR. MPEG-2 video editing.
Windows 95/98/NT. $250.
- Wired
- MediaPress. MPEG-2 encoding hardware (PCI). CBR and VBR. Mac OS
and Windows 95/98/NT. $2,500.
- Zapex
- ZP-200. Real-time PCI encoder for MPEG-2 video and PCM Audio.
Non-real-time encoding and VOB multiplexing from Adobe Premiere. Windows NT.
- ZP-300. Real-time PCI Encoder for CBR/VBR MPEG-2 video, 2-channel
Dolby Digital, and PCM Audio. Non-real-time encoding and VOB multiplexing
from Adobe Premiere. Windows NT.
- Astarte
- A.Pack. Multichannel Dolby Digital audio encoding software for
Mac OS. $800.
- Digital Vision
- BitPack. Multichannel audio encoding workstation for Dolby
Digital, MPEG-2, and PCM.
- Dolby
- DP569. Multichannel Dolby Digital audio encoding hardware.
- Kind of Loud Technologies
- SmartCode Pro/Dolby Digital. 5.1-channel encoding software plugin
for Digidesign Pro Tools. $1000.
- SmartCode Pro/DTS. 5.1-channel encoding software plugin for
Digidesign Pro Tools. $2000.
- Microcosmos
- MPEG SoftEngine/Audio. MPEG audio encoding software for
Windows/Solaris. $95/$350.
- Minerva
- Audio Compressionist. Professional Dolby Digital real-time,
5.1-channel encoder. Windows NT.
- Philips
- DVD3310. Professional MPEG-2 multichannel audio encoder.
- PixelTools
- Expert-Audio. MPEG Layer 2 audio encoding software. Windows.
- Sonic Solutions
- Sonic DVD Studio. Professional real-time Dolby Digital 5.1,
MPEG-2, and PCM audio encoding hardware. Mac OS.
- Sonic Foundry
- Soft Encode. Dolby Digital 2-channel or 5.1-channel audio
encoding software. Windows 95/98/NT. $500 and $900.
- Sony
- DVA-A1100. High-end, real-time Dolby Digital 5.1, MPEG-2, and PCM
audio encoding hardware. Windows NT.
- Spruce Technologies
- ACXpress 2000 (formerly from CagEnt). Professional Dolby Digital
real-time, 2-channel encoder. Windows NT.
- ACXpress 5100 (formerly from CagEnt). Professional Dolby Digital
real-time, 5.1-channel encoder. Windows NT.
- Zapex
- ZP-100. Real-time PCI encoder for 2- or 5.1-channel Dolby Digital
and MPEG Layer 2. Windows NT.
- Captions, Inc. (Burbank, CA),
818-729-9501. Captioning and subtitle services.
- European Captioning Institute (ECI) (London, UK). +44-171-323-4657.
Captioning and subtitle services.
- National Caption Institute (NCI) (LA
818-238-4201; NY 212-557-7011; VA 703-917-7619). Captioning and subtitle
services.
- Vitac (Canonsburg, PA) 888-528-4822.
Captioning services.
- Astarte
- DVDirector and DVDirector Pro. Low-end and high-end
DVD-Video authoring tools for Mac OS. Pro version includes MediaPress
hardware MPEG-2 encoder from Wired.
Millennium Bundle turnkey workstation includes DVDirector Pro,
Mac G4, and more. $5,400, $10,00, $15,000.
- DVDelight. Simple, drag-and-drop DVD-Video authoring for Mac OS.
$1,000.
- DVDExport. Software to convert Macromedia Director presentations
to DVD-Video format. Mac OS. $900.
- Authoringware
- DVD WISE. Authoring system for Windows 95/98/NT. $950.
- DVD Quickbuilder. Multiplexing software.
- Avid
- Xpress DV. Turnkey workstation based on IBM Intellistation
hardware running Avid Xpress software and Sonic Solutions
DVDit. $9,000.
- Blossom Technologies
- DaViD 2000, 4000, 6000, and 10000. Turnkey Windows NT 4.0 systems
using Daikin Scenarist authoring software and Optibase encoding
hardware or Sonic Foundry audio encoding software. $20,000 to $100,000.
- Canopus
- Amber for DVD. Amber MPEG-2 encoding hardware with Spruce
DVDVirtuoso authoring software. $3,300.
- Compact Data
- SimpleDVD. AVI-to-DVD converter for Windows. $1,500.
- Daikin (Daikin US Comtec
Laboratories)
- Scenarist SGI. DVD-Video authoring for SGI. The original. $35,000.
- Scenarist NT. DVD-Video authoring on Windows NT. Comes in three
versions: Basic, $9,000; Advanced, $19,000;
Professional, $29,000.
- DVDwiz. Low-end authoring for NT.
- DreamCom (formerly Gunzameory)
- DVDRich. DVD-Video authoring/encoding on Windows NT. Uses
MPEGRich encoder and Daikin Scenarist or Intec DVDAuthorQuick. $30,000.
- DV Studio
- Apollo Expert Author and Apollo Expert DVDer. DVD-Video
authoring system for Windows NT, using DV Studio Apollo Expert MPEG-2
encoding hardware and Intec DVDAuthorQuick authoring software
(Author package, $4,000) or Sonic DVDit (DVDer package,
$2,500).
- Apollo Expert Archiver. MPEG-2 encoding system for archiving
video to DVD-RAM. $2,500 (DVD-RAM drive included).
- Futuretel
- InnovaCom
- DVDimpact. DVD-Video authoring aimed at multimedia studios and
corporations. Uses InnovaCom DV5100 hardware encoding station and
Daikin Scenarist NT or Intec DVDAuthorQuick software. $47,500
and $29,000.
- Intec America
- DVDAuthorQuick Pro. DVD-Video authoring software for Windows NT.
$8,000.
- DVDAuthorQuick Desktop. Entry-level DVD-Video authoring software
for Windows NT. Appropriate for simple corporate DVD and personal DVD
projects. $2,500.
- Matrox
- Matrox RT2000 and DigiSuite DTV. Video capture and editing
in DV and MPEG-2 formats. Includes Sonic Solution's DVDit LE for
simple DVD authoring. Windows 98. $1,300.
- Microboards
- DVD AuthorSuite. DVD-Video authoring/encoding for Windows NT.
Uses Intec DVDAuthorQuick software, Zapex encoders, and Sigma Designs
decoder. $25,000.
- Minerva
- DVD-Professional SL and DVD-Professional XL. DVD-Video
authoring/encoding systems for Windows NT. Includes Publisher 300 and
Minerva Studio. $100,000.
- Impression. DVD-Video authoring/encoding system for Windows.
$10,000.
- MTC (Multimedia Technology Center)
- StreamWeaver Express and StreamWeaver Pro. DVD-Video
authoring, and $900 premastering on Windows. $900 and $3,000.
- DVMotion Express and DVMotion Pro. Authoring systems for
Windows, oriented toward multimedia DVD-ROM production. $1,500 and $5,000.
- DVDMotion CE. Entry-level authoring system for Windows 98/NT4.
$75.
- NEC
- DV Editor. IEEE-1394 card and and software, plus Sonic's DVDit
LE. Windows 98. Available in Japan only.
- Optibase
- DVD-Fab XPress and DVD-Fab. Turnkey DVD-Video
authoring/encoding systems for Windows NT. Includes Optibase MPEG
Fusion MPEG-2 encoder and Daikin Scenarist authoring software.
$35,000.
- Panasonic
- LQ-VD2000S. Turnkey DVD-Video authoring system, including Windows
NT 4.0 workstation. Uses Panasonic MPEG-2 encoder and LQ-VD3000
emulator. $120,000.
- LQ-VDS120. Additional workstation software for networking with
LQ-VD2000S. $22,550
- LQ-VD3000. DVD Emulator. $15,000
- Pinnacle
- DVD1000. MPEG-2 video editing and DVD-Video authoring system for
Windows. Pinnacle DVD1000 hardware with Adobe Premiere and Minerva
Impression. $8,000.
- Philips
- DVD-Video Disc Designer and DVD-Video Authoring Toolset.
Windows NT.
- Pioneer
- DVDDesigner. An off-line design tool for DVD-Video planning and
layout. Can feed an "authoring decision list" into other authoring systems.
Available free to qualified developers. Windows and Mac OS.
- Q-Comm
- Sonic Solutions
- DVD Creator. DVD-Video authoring/encoding systems for corporate
and industrial applications. Can also author DVD-Audio discs. Mac OS. Four
configurations: Authoring Workstation, $20,000; Creator
Workstation, $40,000; Creator All-in-One Workstation, $80,000;
Creator AV Workstation, $100,000.
- DVD Creator 2. Mac OS. $12,000.
- DVD Fusion. Add-on for Avid and Media 100 digital editing
systems. Software-only or hardware-accelerated. Mac OS.
- DVDit LE (limited), SE (standard), and PE
(professional). Simple, drag-and-drop DVD-Video authoring for Windows.
$500 (SE), $3,000 (PE). LE version is designed to be bundled with
other hardware and software products.
- DVDit for Premiere. Adobe Premiere plug-in for DVD-Video output.
Windows. $400.
- Sony
- DVA-1100. High-end authoring/encoding system with one to eight
stations. Price range starts at $175,000.
- Spruce Technologies
- DVDConductor and DVDMaestro. Authoring/encoding systems
for Windows NT. Also allow DVD content to be recorded and played from CD-R.
$10,000 and $25,000.
- DVDVirtuoso. Low-end authoring/encoding system for Windows NT.
Only available bundled with other products.
- DVDStationCX. Turnkey system using DVDConductor. $25,000.
- DVDStationNLE. Turnkey system using DVDConductor and Heuris
MPEG Power Professional encoding software. $10,000.
- Visible Light
- Macarena and Macarena Pro. DVD-Video authoring for Power
Mac G4. Software encoding or hardware encoding (Pro version). Uses Astarte
DVDirector software. $10,000 and $15,000.
- Vitech
- DVD Toolbox. AVI to DVD-Video. Write to CD-R, DVD-R, DVD-RAM,
etc. Windows 95/98/NT. $400.
- DVD Cut Machine. Hardware audio/video encoder bundled with DVD
Toolbox software. $800.
[A] = authoring (including encoding, DVD-R copies, and
premastering).
[R] = replication (mastering and check discs).
- [A] 12CM Multimedia (Mountain View, CA,
650-564-9000; Santa Clara, CA 408-350-9000).
- [A] 4MC (London, UK), +44 171 878 7884.
[Acquired Post Box, Stream, and TVP.]
- [A] Abbey Road Interactive
(London, UK), +44 171 266 7000.
- [A] Accudigital Media Services
(Castro Valley, CA), 510-247-9940.
- [A] Alchemey Digital Video
(Portland, OR), 503-274-4345.
- [A] All Post (CA), 818-556-5756.
- [A] Aludra (Ontario, Canada),
888-552-5837.
- [R] Americ Disc, see MPO/Americ.
- [A] asv multimedia (Mengen, Germany),
07572/78361.
- [A] Atelier Digital
(Birmingham, AL), 205-263-7678.
- [A] Audio Plus Video International
(Northvale, NJ, 201-767-3800; Burbank, CA, 818-841-7100).
- [A] AVCA (Austin, TX), 512 472-4995.
- [A] AVM Dialog AB (Goteborg,
Sweden).
- [A] B1 Media (Sherman Oaks, CA),
818-905-9902.
- [A] BCD Associates (Oklahoma City,
OK), 405-843-4574.
- [A] Blue City Digital (North Kansas City,
MO), 816-300-0441.
- [A] C&C interactive AB (Boras,
Sweden), +46 33 290700.
- [A] California DVD (San Francisco,
CA), 1-800-864-1957.
- [A] CBO Interactive (Los Angeles,
CA), 323-468-9580.
- [A] Chicago Recording Company (Chicago, IL), 312-822-9333.
- [A] Cine-Magnetics (Armonk,
NY, 914-273-7500; Studio City, CA, 818-623-2560), 800-431-1102.
- [A] Cinram POP DVD Center (Santa Monica, CA).
- [R] Cinram (Huntsville, Alabama,
256-859-9042; Anaheim, CA, 714-630-6700; Richmond, IN, 800-865-2200;
Scarborough, Ontario, Canada, 416-298-8190), 800-433-DISC.
- [A] CKS|Pictures (CA & NY),
408-342-5009.
- [A] Complete Post (Hollywood,
CA), 323-860-7622.
- [R] Concord Disc Manufacturing
(Brea, CA), 714-579-6600.
- [A] CREATIVVIDEO & DIALOGOS
(Moedling, Austria), +43(0)2236-48311.
- [A] CRUSH Digital Video (NY),
212-989-6500.
- [A] CruSh Interactive,
(Houston, TX), 713-972-1133.
- [A] Cut & Copy (Vienna,
Austria), +43 1 523 98 24.
- [A] CVC (Los Angeles, CA),
818-972-0200. (Time Warner California Video Center)
- [A] D2 Productions (CA),
818-576-8113.
- [A] Dallas Digital
Transfer (Dallas, TX), 214-336-6292.
- [R] Deluxe
Video Services (Carson City, CA), 310-518-0710. (Formerly Pioneer Video
Manufacturing)
- [A] Designlab Systems, (London,
UK), +44 (0) 207 437 5621.
- [A] Digidisc (Atlanta, GA)
770-925-1839.
- [A] Digital Farm (Seattle, WA),
206-634-2677.
- [A] Digital Group (London, UK)
- [A] digital images (Halle, Germany),
+49 (0)345/2175-101.
- [A] Digital Media Group (Amsterdam, The
Netherlands), +31-20-422-6317.
- [A] Digital Metropolis
(Denver, CO), 303-292-4692.
- [A] Digital Outpost (CA), 800-464-6434.
- [A] Digital Video Compression
Corporation (CA), 818-777-5185.
- [A] Digital Video Dynamix (Seaford, NY), 516-826-6414.
- [A] Digital Video Mastering (Sydney, Australia).
- [R] Digital Video Technology 3000
(DVT) (El Segundo, CA).
- [A] Digiverse (London, UK), +44
(0) 20 7287 3141.
- [R] Disc Manufacturing Inc. (now part of Cinram).
- [R] Disk Press International
(Erembodegem, Belgium), +32 53 78 48 14.
- [A] DGP (London, UK), +44 0 207
734 4501.
- [R] DOCdata (Tilburg, The
Netherlands, +31 13 544 6444; Berlin, Germany, +49 30 467 0840; Sanford, ME,
USA, 207-324-1124; Canoga Park, CA, USA 818-341-1124).
- [A] DVD Labs (Princeton, NJ),
888-DVD-LABS.
- [A] DVD Master (Fountain Valley,
CA), 714-962-4098.
- [A] DVD Recording Center
(Acton, MA), 800-321-8141.
- [A] DVD Technologies (Sydney,
Australia), 1-300-FOR-DVD.
- [A] DVD Scandinavia
(Copenhagen, Denmark), +45 3581-7585.
- [A] DVData (Carson, CA)
310-513-0757.
- [A] Dynamic Media (Ellicott
City, MD), 410-203-2553.
- [AR] DV Line (Seoul, Korea),
82-2-3462-0331.
- [A] EagleVision (Stamford,
CT), 800-EAGLE73.
- [A] EDS Digital Studios (CA), 213-850-1165.
- [A] Electric Switch (London),
+44-0-131-555-6055.
- [A] E-M-S (Dortmund, Germany), 0231
442411-0.
- [A] eVideo (Burbank, CA)
818-559-4268.
- [A] FATdisc (Seattle, WA),
425-837-1791.
- [A] Film- und Videotechnik B. Gurtler (Munchen, Germany).
- [A] Firefly (Ireland).
- [A] Fitz.com (Santa Monica, CA)
310-315-9160.
- [A] Forest Post Productions
(Farmington Hills, MI), 248-855-4333.
- [A] Full Circle Studios
(Buffalo, NY), 716-875-7740.
- [A] FULLSTREAM DVD (Dallas,
TX), 214-969-1820.
- [R] Future Media Productions (Valencia,
CA), 661-294-5575.
- [A] Future Disc Systems
(West Hollywood, CA), 323-876-873.
- [A] G9 Interactive (Monrovia, CA), 626-358-0859.
- [A] Gateway Mastering Studios (Portland, OR).
- [A] GTN (Oak Park, MI), 248-548-2500.
- [A] Hecker & Schneider GmbH (Dortmund, Germany).
- [A] Henninger Interactive Media
(Arlington, VA), 703-243-3444.
- [A] Hoek & Sonépouse (Diemen, The
Netherlands), +31 020 - 69 09 141.
- [AR] Home Run Software Services
(Huntington Beach, CA), 714-375-5454.
- [A] Ibis Multimedia
(Suffolk, UK), +44 1449 678910.
- [A] IBM InteractiveMedia
(GA), 770-835-7193.
- [A] IBT Media (Merriam, KS),
913-677-6655.
- [R] Imation (formerly 3M) (WI), 612-704-4898.
- [R] Infodisc (Taipei, Taiwan).
- [A] International Digital Centre
(IDC) (New York, NY), 212-581-3940.
- [A] IPA Intermedia (IL),
773-871-6033.
- [R] IPC Communication Services
(Foothill Ranch, CA), 949-588-7765.
- [R] JVC Disc America (Sacramento,
CA), 310-274-2221.
- [AR] KAO Infosystems (Fremont, CA),
800-525-6575.
- [AR] Kao (Ontario, Canada), 800-871-MPEG.
- [A] k-kontor[Hamburg] kommunikations
(Hamburg, Germany), +49-40-850-9021.
- [AR] LaserPacific (CA),
213-462-6266.
- [A] Marin Digital (San Rafael,
CA), 415-507-0470.
- [A] Main Point Interactive (Oley,
PA), 610-987-9320.
- [AR] Marcorp (Pittsburgh, PA),
800-284-6277.
- [A] Mastering Studio München
(Munich, Germany), +49-89-286692-0.
- [R] Maxell Multimedia (Santa Clara,
CA), 800-325-7717.
- [AR] Media Group (Fremont, CA), 815-356-9484.
- [AR] Memory-Tech Corporation (Tokyo, Japan).
- [A] MEP Medienhaus (Frankfurt,
Germany), +49 (0)69 78960202.
- [AR] Mercury Entertainment
(Selangor Darul Ehsan, Malaysia).
- [R] Metatec (OH), 614-761-2000.
- [A] Metcom Video (London, UK),
+44 (0)207 836 2772.
- [A] Microsoft Studios Digital Video
Services (Redmond, WA).
- [A] Mills/James Productions
(Columbus, OH), 614-777-9933.
- [A] Mirage Video Productions
(Boulder, CO), 303-786-7800.
- [A] MPEG Production (Stockholm,
Sweden) +46-8-324030.
- [R] MPO/Americ (Salida, CA,
888-545-7350; Miami, FL, 800-364-0759; Drummondville, Quebec, Canada, 800
263-0419; Ireland; Spain, Thailand).
- [R] MRT Technology (Ritek partner)
(City of Industry, CA), 626-839-5555.
- [R] Nimbus CD International (see
Technicolor).
- [A] NOB Interactive (Netherlands), +31
(0)35-677-5413.
- [A] NordArt Video & Multimedia
(Sundbyberg, Sweden), +46 8764 66 90.
- [A] Oasis Post (Kent Town,
South Australia), +61 8 8362 2888.
- [R] Optical Disc Corporation,
310-946-3050. (LaserWave DirectCut DVD recorder for creating single copies.)
- [R] Optical Disc Media (CA).
- [A] Option Facilities (Mechelen,
Belgium), +32/15/28 73 00.
- [A] Pacific Coast Sound Works (CA), 213-655-4771.
- [R] Pacific Mirror Image (Melbourne, Australia).
- [A] Pacific Ocean Post (CA), 310-458-9192.
- [A] Pacific Video Resources (CA),
415-864-5679.
- [AR] Panasonic Disc Services
Corp (Torrance, CA), 310-783-4800.
- [A] Paris Media System (Paris, France).
- [A] The Pavement (London, UK),
+44 (0) 207 426 5190.
- [A] PIMC (Professional Interactive Media
Centre) (Diepenbeek, Belgium), +32 11 303690.
- [A] Pioneer France (Nanterre, France), 33 1 47 60 79 30.
- [R] Pioneer Video (Kofu, Japan).
- [AR] PolyGram Manufacturing & Distribution Center (Langenhagen,
Germany), +49 511 972 1486.
- [A] Positive Charge Ltd.
(Warszawa, Poland), +48 22 632 97 32.
- [A] PRC Digital Media (Jacksonville,
FL), 904-354-5353.
- [A] Provac Disc Media
(Toronto, Ontario), 800-876-9013.
- [A] Rage DVD & Multimedia
(Dallas , TX), 214-358-2588.
- [A] Rainmaker New
Media (Burbank, CA), 818-526-1500.
- [A] Riccelli Creative (Fort
Worth, TX), 817-332-7777.
- [A] RISE Int'l. Inc. (Fort Worth,
TX), 800-990-2348.
- [AR] Ritek (HsinChu, Taiwan, ROC),
+886-2-29979111.
- [A] Sharpline Arts (Glendale,
CA), 818-500-3958.
- [AR] Sonopress (Gütersloh,
Germany, +49-5241-80 5200; Weaverville, NC, USA, 828-658-2000)
- [R] Sony DADC (Niederalm, Austria),
+43 624 688 0555.
- [R] Sony Disc Manufacturing (Terre
Haute, Indiana), 541-988-8000.
- [A] Sound Chamber Mastering
(North Hollywood, CA), 818-752-7581.
- [A] Star Video Duplicating
(Phoenix, AZ), 602-437-0646.
- [A] Stay Tuned (Brussels, Belgium),
+32 2 7611100.
- [A] Stimulus (Calgary, Alberta).
- [A] Sté EXILOG (Vendoeuvres
FRANCE), 33 02 54 38 30 95.
- [A] Stonehenge Filmworks (Toronto
and Ontario, Canada), 416-867-1189.
- [A] Sunset Post (CA),
818-956-7912.
- [A] Supersonic Media
Productions (Vancouver, BC), 604-683-0250.
- [A] Sync Sound (NY), 212-246-5580 (5.1 audio).
- [A] Syrinx music & media GmbH
(Hamburg, Germany), +49-40-63709230.
- [R] Technicolor (Camarillo, CA,
805-445-1122; Charlottesville, VA, 804-985-1100; Cwmbran, Wales, UK,
44-1163-465-000), 800-732-4555.
- [A] Tele-Cine (London, UK), +44
(0) 171 208 2200.
- [R] TIB.
- [A] Valkieser Solutions (Hilversum,
Netherlands), +31-35-6714-300.
- [A] VDI Multimedia (Chicago,
Dallas, Los Angeles, New York, San Francisco), 323-957-7990.
- [A] Video Movie Magic
(Laguna Hills, CA), 949-582-8596.
- [A] Video Transfer (Boston, MA),
617-247-0100.
- [A]
Visible Light Digital (Orlando, FL),
407-327-7804.
- [A]
The Vision Factory (St. Louis, MO),
314-963-7887.
- [A]
Vision Wise (Irving, TX),
888-979-9473.
- [AR] Warner Advanced Media Operations, 717-383-3291.
- [AR] Zomax, (Plymouth, MN,
612-577-3515; Fremont, CA, 510-492-5191; Indianapolis, IN, 510-492-5191;
Dublin, Ireland, 353-1-405-6222; Langen, Germany, 49-6103-9702-23).
Also see DVD Insider professional services
directory and Medialine Weblinks.
- Audio Development AB (Sweden, USA,
Hong Kong), +46 40 690 49 00.
- CD Associates (CA). Testing
equipment and software. (714) 733-8580.
- ContentWise (Rehovot, Israel),
+972-8-940-8773. Second Sight software for checking compatibility of
DVD titles on multiple players.
- Hitachi (Japan). Testing services and test discs. Official DVD Forum
verification lab.
- Intellikey Labs (CA), (562)
426-5338 [Long Beach Office], (818) 953-9116 [Burbank Office].
- Interra Digital Video
Technologies: Surveyor software, $6,000. DProbe, $10,000.
- ITRI (HsinChu, Taiwan). Testing
services and test discs. Official DVD Verification Lab. 886-3-591-5066, fax
886-3-591-7531.
- Matsushita (Japan). Testing services, test discs, and test equipment.
Official DVD Verification Lab. +81-6-6900-9241, fax +81-6-6907-2013.
- Philips
(Europe), DVD-Video Verifier software, $500. Official DVD Verification
Center.
- Pioneer (Japan). Testing services and test discs. Official DVD
Verification Lab. +81-3-3495-5474, fax +81-3-3495-4301.
- PMTC (Professional Multimedia Test
Centre) (Diepenbeek, Belgium), +32 11 303636.
- Sony (Japan). Testing services and test discs. Official DVD Format Lab.
+81-3-5448-2200, fax +81-3-5448-3061.
- Toshiba (Japan). Testing services and test discs. Official DVD
Verification Lab. +81-3-3457-2105, fax +81-3-5444-9202.
- Victor (Japan). Testing services and test discs. Official DVD Verification
Lab. +81-3-3289-2813, fax +81-45-450-1639.
- WAMO (USA). Testing services and
test discs. Official DVD Forum verification lab. 1-570-383-3568, fax
1-570-383-7487.
[Note: This section refers to creating original DVD-Video
content, not copying from DVD to CD. The latter is impractical, since it takes 7
to 14 CDs to hold one side of a DVD. Also, most DVD movies are encrypted so that
the files can't be copied without special software.]
There are many advantages to creating a DVD-Video volume using inexpensive
recordable CD rather than expensive recordable DVD. The resulting "MiniDVD" is
perfect for testing and for short video programs. Unfortunately, you can put
DVD-Video files on CD-R or CD-RW media, or even on pressed CD-ROM media, but as
yet there is no settop player that can play the disc. There are a number of
reasons DVD-Video players can't play DVD-Video content from CD media:
1)
checking for CD media is a fallback case after DVD focus fails, at which point
the players are no longer looking for DVD-Video content
2) it's simpler and
cheaper for players to spin CDs at 1x speed rather than the 9x speed required
for DVD-Video content
3) many players can't read CD-R discs (see 2.4.3).
Computers are more forgiving. DVD-Video files from any source with fast
enough data rates, including CD-R or CD-RW, with or without UDF formatting, will
play back on any DVD-ROM PC as long as the drive can read the media (all but
early model DVD-ROM drives can read CD-Rs). Author the DVD-Video content as
usual (see 5.4) then
burn the VIDEO_TS directory to the root drive of a CD-R or CD-RW. To be
compatible with future settop players that might read MiniDVDs, turn on the UDF
filesystem option of the CD burning software. To achieve longer playing times,
encode the video in MPEG-2 half-D1 format (352x480 or 352x576) or in MPEG-1
format. There are various DVD authoring packages that can put DVD content on
CD-R/RW, even for use in computers that have only a CD-ROM drive, such as Daikin ReelDVD, Sonic DVDit, and Spruce DVDonCD.
An alternative is to put Video CD or Super Video CD content on CD-R or CD-RW
media for playback in a DVD player. Settop players that are VCD or SVCD capable
and can read recordable media will be able to play such discs (see 2.4.5). The
limitations of VCD apply (MPEG-1 video and audio, 1.152 Mbps, 74 minutes of
playing time). All DVD-ROM PCs able to read recordable CD media can play
recorded VCD discs. An MPEG-2 decoder (see 4.1) is need to play
SVCDs. See 5.8 for
more on creating Video CDs.
If you're rich enough, put together a system with the following
components
- a video digitizer ($200-$10,000)
- an MPEG-2 video encoder ($150-$35,000)
- a Dolby Digital audio encoder ($800-$5,000)
- a DVD-Video authoring application ($500-$70,000)
- a DVD-R recorder ($5,000)
Then take the following steps
- digitize the audio and video from VHS, Hi8, DV, or whatever (for slides,
use a scanner; for film, get it transferred to tape or digital video at a
camera shop or video company)
- encode the video into MPEG-2 (make sure the display frame rate is set to
29.97 for NTSC or 25 for PAL)
- encode the audio into Dolby Digital (or, if your video is short enough
that you have room on the disc, format the audio as 48kHz PCM)
- bring the video and audio clips into the DVD-Video authoring program
- create a menu or two if you're ambitious, and link the menu buttons to
your video clips
- if you're converting slides, use the slideshow feature or turn them into
menus (most authoring systems will read TIFF, JPEG, or PhotoShop files)
- create some chapter points if you're really ambitious (if your authoring
program supports this)
- write your finished gem out to a DVD-R ($30)
Otherwise, if you're like most of us and you make less money in
year than Bill Gates does in a day, then wait until sometime in 2001 when all
the above functionality is available for only a few thousand dollars. Or, in the
meantime, find someone who has the above system and will transfer your video for
a reasonable fee. Here are a few choices.
Or, if MPEG-1 video quality is sufficient for your needs, get
MPEG-1 encoding software and a CD-R/RW formatting application that supports
Video CD (such as Easy CD Creator or Toast from Adaptec, InternetDiscWriter from Query, MPEG Maker-2 from VITEC, Nero Burning ROM from Ahead, NTI CD-Maker from NTI, or WinOnCD from Cequadrat). Quality won't be as good, and
playing time won't be as long, but software, hardware, and blank discs will be
much cheaper. Just make sure that any players you intend to play the disc on can
read CD-Rs (see 2.4.3) and can play
Video CDs (see 2.4.5). A variation
on this strategy is to make Super Video CDs (see 2.4.6), which have
better quality but shorter playing time. SVCD support is being added to a few of
the authoring/formatting tools listed above.
Read this FAQ through a few times. For extra credit read my book, DVD Demystified, and visit some of the DVD
information sources listed in section 6.4. Then attend a
conference (see 5.10) to learn more
and to make contacts in the DVD industry. Take a few training courses (see 5.10). Consider
joining the DVDA. If you can, volunteer to be
an intern at a DVD production house (see 5.4).
Once you have a little experience, you'll be in great demand! Register at DVDJobsUSA.com and check the listings at
DVDArtist.
A variety of workshops and seminars on various DVD topics are presented at
conferences such as DVD Pro, DVD Summit (Europe) or DVD Production.
Training companies offer DVD courses and "boot camps":
The major DVD authoring software companies offer training courses, sometimes
for free:
DVD is the work of many companies and many people. There were originally two
competing proposals. The MMCD format was backed by Sony, Philips, and others.
The SD format was backed by Toshiba, Matsushita, Time Warner, and others. A
group of computer companies led by IBM insisted that the factions agree on a
single standard. The combined DVD format was announced in September of 1995,
avoiding a confusing and costly repeat of the VHS vs. Betamax videotape battle
or the quadraphonic sound battle of the 1970s.
No single company "owns" DVD. The official specification was developed by a
consortium of ten companies: Hitachi, JVC, Matsushita, Mitsubishi, Philips,
Pioneer, Sony, Thomson, Time Warner, and Toshiba. Representatives from many
other companies also contributed in various working groups. In May 1997, the DVD
Consortium was replaced by the DVD Forum,
which is open to all companies, and as of February 2000 had over 220 members.
Time Warner originally trademarked
the DVD logo, and has since assigned it to the DVD Format/Logo Licensing
Corporation. The term "DVD" is too common to be trademarked or owned. See
section 6.2 and
visit Robert's DVD Info page
for links to Web sites of companies working with DVD.
The official DVD specification books are available after signing a
nondisclosure agreement and paying a $5,000 fee. One book is included in the
initial fee; additional books are $500 each. Manufacture of DVD products and use
of the DVD logo for non-promotional purposes requires additional format and logo
licenses, at $10,000 per format. (E.g., a DVD-Video player manufacturer must
license DVD-ROM and DVD-Video for $20,000.) Contact DVD Format/Logo Licensing
Corporation (DVD FLLC), Shiba Shimizu Building 5F, Shiba-daimon 2-3-11,
Minato-ku, Tokyo 105-0012, tel: +81-3-5777-2881, fax: +81-3-5777-2882. Before
April 14, 2000, logo/format licensing was administered by Toshiba.
ECMA has developed international standards for DVD-ROM (part 1, the smallest
part of the DVD spec), available for free download as ECMA-267 and ECMA-268 from http://www.ecma.ch/. ECMA has also standardized
DVD-R in ECMA-279,
DVD-RAM in ECMA-272
and ECMA-273, and
DVD+RW as ECMA-274
(see 4.3).
Unfortunately, ECMA has the annoying habit of spelling "disc" wrong. Also
confusing, if you're not from Europe, is ECMA's use of a comma instead of a
period for the decimal point.
The specification for the UDF file system used by DVD is available from http://www.osta.org/.
Any company making DVD products must license essential technology patents
from a Philips/Pioneer/Sony pool (3.5% per player, minimum $5; additional $2.50
for Video CD compatibility; 5 cents per disc), a
Hitachi/Matsushita/Mitsubishi/Time Warner/Toshiba/Victor pool (4% per player or
drive, minimum $4; 4% per DVD decoder, minimum $1; 7.5 cents per disc) and from
Thomson. Patent royalties may also be owed to Discovision Associates, which owns about
1300 optical disc patents (usually paid by the replicator).
The licensor of CSS encryption technology is DVD CCA (Copy Control Association), a
non-profit trade association with offices at 225 B Cochrane Circle, Morgan Hill,
CA. There is a $10,000 initial licensing fee, but no per-product royalties. Send
license requests to css-license@lmicp.com, technical info
requests to css-info@lmicp.com. Before
December 15, 1999, CSS licensing was administered on an interim basis by
Matsushita.
Macrovision licenses its analog anti-recording technology to hardware makers.
There is a $30,000 initial charge, with a $15,000 yearly renewal fee. The fees
support certification of players to ensure widest compatibility with
televisions. There are no royalty charges for player manufacturers. Macrovision
charges a royalty to content publishers (approximately 3 to 6 cents per
disc).
Dolby licenses Dolby Digital decoders for
$0.26 per channel. Philips, on behalf of CCETT and IRT, also charges $0.20 per
channel (maximum of $0.60 per player) for Dolby Digital patents, along with
$0.003 per disc.
An MPEG-2 patent license may also be required, from MPEG LA (MPEG Licensing Adminstrator). Cost is
about $4 for a DVD player or decoder card and 4 cents for each DVD disc,
although there seems to be disagreement on whether content producers owe
royalties for discs.
Nissim claims 25 cents per player for
parental management patents, but there is disagreement on whether the patents
apply to DVD and if they are valid.
Various licensing fees add up to over $30 in royalties for a $300 DVD player,
and about $0.20 per disc. Disc royalties are paid by the replicator.
- Aiwa: DVD-Audio and DVD-Video players
- Akai: DVD-Video players
- Apex Digital: DVD-Video players (made by VDDV; info at http://www.nerd-out.com/apex and http://aenow.com/apex/)
- Alpine: DVD car
navigation/entertainment
- Altec Lansing: DVD audio
technology
- Ariston: DVD-Video players
- Audiovox: Car DVD players
- AV Phile (Raite): DVD-Video Players
- BUSH: DVD-Video players
- California Audio Labs: DVD-Video
players
- Casio: DVD-Video players
- Clarion: DVD car
navigation/entertainment
- Comjet: DVD-Video players with Web
connection
- Compro: DVD-Video players
- Denon: DVD-Audio and DVD-Video players
- Daewoo Electronics: DVD-Video
players
- DVDO: video deinterlacing processors
- Emerson: DVD-Video players
- Enzer: DVD-Video players
- Esonic: DVD-Video players
- Faroudja: DVD-Video players
- Fisher (Sanyo): DVD-Video players
- Funai: DVD-Video players
- GPX/Yorx: DVD-Video players
- Great Wall: DVD-Video players
(Hong Kong)
- Grundig: DVD-Video players
- Guangdong Jinzheng Digital:
DVD-Video players
- Harman Kardon: DVD-Video
players
- Hitachi: DVD-Video players
- Hoyo (Raite): DVD-Video Players
- Hyundai: DVD-Video players
- Innovacom: PC/TV with DVD
support
- I-Jam: DVD-Video players
- JVC (Victor): DVD-Video players
and changers
- Kenwood: DVD-Video players
- KISS (Raite): DVD-Video players
- Konka: DVD-Video players
- Lasonic: DVD-Video players
- Lector: DVD-Video players
- LG Electronics (GoldStar): DVD-Video
players
- Madrigal (Mark Levinson): DVD-Audio
and DVD-Video players
- Magnavox (Philips): DVD-Video players
- Marantz (Philips): DVD-Audio,
SACD, and DVD-Video players
- Matsushita
(Panasonic/National/Technics/Quasar): DVD-Video and DVD-Audio players, DVD car
navigation/entertainment
- Matsui: DVD-Video players
- Medion: DVD-Video players
- Meridian: DVD-Video players
- Micromega: DVD-Video players
- Mitsubishi: DVD-Video players
- Monica/Monyka (Raite): DVD-Video players
- Mossimo: DVD-Video players (China)
- NAD: DVD-Video players
- Nakamichi: DVD-Audio and
DVD-Video players
- Nintaus (Guangdong Jinzheng):
DVD-Video players
- NEC: DVD-RAM video
camera
- Noriko: DVD-Video players
- Olidata: DVD-Video players (Italy)
- Onkyo: DVD-Video players
- Optics-Storage: DVD-RW
video recorders (supplier)
- Oritron: DVD-Video players
- Palsonic (Australia): DVD-Video players
- Panasonic (Matsushita): DVD-Video
and DVD-Audio players and changers
- Philips (Magnavox/Marantz/Norelco):
DVD-Video players
- Pioneer: DVD-Video and
DVD-Audio players and changers, DVD car navigation/entertainment
- Proscan (Thomson):
DVD-Video players
- Proton: DVD-Video players
- RCA (Thomson): DVD-video players
- Raite: DVD-video players (Taiwan)
- RCR: DVD-Video players (China)
- REC: DVD-Video players (UK, made by VDDV, same as APEX)
- Roadstar: DVD-Video players
- Rotel: DVD-video players
- Runco: DVD-video players and changers
- Sampo: DVD-Video players
- Samsung: DVD-Video
players
- Sanyo:
DVD-Video players
- Sensory Science: DVD-Video
players (formerly Go-Video)
- Sharp: DVD-Video players
- Shinco: DVD-Video players (Hong
Kong)
- SMC: DVD-Video players
- Sony: DVD-Video players and
changers
- Spatializer Audio Laboratories:
3D audio processing
- Teac: DVD-Video players
- Technics
(Matsushita): DVD-Video and DVD-Audio players
- Teknema (Ravisent): Web-connected
DVD-Video players
- Thakral: DVD-Video players
(China, Hong Kong)
- Theta: DVD-Video players
- Thomson
(RCA/GE/Proscan/Ferguson/Nordmende/Telefunken/Saba/Brandt): DVD-Video players
- Tokai (Raite): DVD-Video Players
- Toshiba: DVD-Video and
DVD-Audio players and changers
- Unity Motion: DVD-Video players
- Victor (JVC): DVD-Video players
- Visual Disc and Digital Video:
DVD-Video players (China)
- Wharfedale: DVD-Video players
- Yamaha: DVD-Audio and DVD-Video
players
- Yamakawa (Raite): DVD-Video players
- Zenith (becoming a subsidiary of LG): DVD-Video players
- A2O Entertainment
(wholesale distributor)
- A.D. Vision (anime)
- Acorn Media
- Aftermath Media (Tender
Loving Care, interactive movie)
- All Day Entertainment
- Alphaville Pictures (distributed by Universal)
- Amazing Fantasy
- Amblin Entertainment (distributed by Universal)
- American Gramaphone
- American Software
- Anchor Bay Entertainment
- Animeigo
- A-Pix Entertainment
- Artisan Home
Entertainment (formerly LIVE Entertainment)
- Arts & Entertainment DVD
- Atomic Video (adult)
- Avalanche
- Baby Einstein (infant
development)
- Baker & Taylor (distributor)
- Beyond Music (distributor)
- Black Chair Productions
(independent films)
- Black Entertainment Television (BET)
- BMG (Sonopress)
- Brentwood
- Brilliant Digital Entertainment (multipath movies)
- BroadcastDVD
- Buena Vista Home Video (Disney)
- CAV Distributing (distributor)
- Cecchi Gori
- Celebrity
- Central Park Media
- Cerebellum (educational)
- Chesky
- Classic Records
- Columbia TriStar (Sony)
- Compact Media (distributor)
- Concert @ Home (Platinum Entertainment)
- Concorde Video (12 Monkeys, German)
- Corinth Films (Wade Williams Collection)
- Creative Design Art
- Criterion Collection
- DaViD Entertainment
- Delos International (mostly audio)
- Delta Entertainment
- DG Distributors (distributor)
- Diamond
Entertainment (distributor)
- Digital Disc Entertainment
- Digital Leisure (formerly
ReadySoft) (Dragon's Lair, Space Ace)
- Digital Multimedia
- Digital Versatile Disc
- Dimension Films (Miramax)
- Direct Source
- Direct Video Distribution (distributor, UK)
- Disney (Buena Vista Home Video,
Dimension Films, Hollywood Pictures, Miramax, Touchstone)
- Dream Theater
- DreamWorks SKG
- DVD International
(distributor)
- D-Vision
- Eaton Entertainment
- Elite
Entertainment
- EMI Records
- E Real Biz
- Essex Entertainment
- Fantoma
- FOCUSFilm Entertainment
- Fox Lorber
- Front Row
- Full Moon Pictures
- Gainax (anime)
- General Media Communications (Penthouse) (adult)
- Goldhil Home Media
- Goodtimes Entertainment
- Gramercy Pictures (distributed by Universal)
- Hallmark Home Entertainment (Artisan)
- HBO Home Video (Warner)
- Hollywood Pictures (Disney, folded
into Touchstone)
- Hot Body International (adult)
- Ice Storm Entertainment (distributor, Germany)
- Ideal Entertainment
- Image Entertainment
(distributor)
- Impressive (adult)
- IndieDVD (publisher; alliance of
independent filmmakers)
- Ingram (distributor)
- Key East
- King's Road (distributed by Trimark)
- Kino International
- Laserdisc Entertainment (adult)
- Laserlight
- Lee & Lee Films
- Leo Films
- Living Arts (health)
- LucasFilm (distributed by Twentieth Century Fox or Paramount)
- Lucerne Media (educational)
- Lumivision (distributed by SlingShot)
- Lyric
- MacDaddy
- Madacy
- Magic Lantern
- Marin Digital (Your Yoga
Practice)
- Master Tone
- MCA (Universal)
- MCA Music
- Media Galleries
- Media Group (distributor)
- Metro Global Media (adult)
- Metromedia
- MGM/UA (Warner)
- Mill Reef (Earthlight)
- Miramax Films (Disney)
- Monarch Home Video
- Monterey
- MPI Home Video
- MTI
- Multimedia 2000 (aka M-2K)
- Music Video Distributors (distributor)
- N2K Music
- Navarre (distributor)
- Nettwerk Productions
- New Horizons Home Video
- New Line (Warner)
- New Video Group
- New Vision
- New York Entertainment
- NuTech Digital (adult)
- October Films (Universal)
- Opera World
- Orion Pictures (MGM, some older DVD titles distributed by Image and
Criterion)
- Overseas Filmgroup (distributor, partner
with Image)
- Pacific Digital
- Palm Pictures
- Panasonic Interactive Media (defunct)
- Panorama
- Paramount Home Video
(owned by Viacom)
- Parasol
- Passport Video
- Phantom Video
- Picture This Home Video
- Pioneer Entertainment
(distributor)
- Platinum
- Playboy Home
Video
- PM Entertainment
- Polygram (Philips partner)
- Pony Canyon (Japan)
- PPI Entertainment
- Private Media Group (adult)
- Pro7 Home Entertainment (Germany)
- Program Power
- Real Entertainment
- Red Distribution (distributor)
- Renegade
- Republic Pictures (defunct, distributed by Artisan)
- Rhino Home Video
- Roadshow Entertainment (Australia)
- Roan Group
- Rykodisc
- Samsung Entertainment Group
- Shanachie
- Showtime
- Simitar Entertainment
- Sierra Vista Entertainment (Innovacom)
- Silver Screen
- SlingShot (acquired Lumivision
titles)
- Sony Music Entertainment
- Sony Pictures (Columbia, Epic, Sony Music, Sony Wonder, TriStar)
- Sony Wonder (kids)
- Steeplechase
- Sterling Home Entertainment
- Super Digital Media
- SyCoNet.com (distributor,
anime)
- Synapse Films
- Tai Seng
- Tempe Entertainment
- Thakral (distributor; Hong Kong,
China)
- Toho (Japan)
- Tone Home Video
- Toshiba EMI
- Touchstone (Disney)
- Trimark Pictures
- Troma Entertainment
- Turner Home Entertainment
- Twentieth Century Fox Home
Entertainment
- Unapix Entertainment
- United American
- United Artists (MGM)
- Universal Studios Home
Video (owned by Seagram)
- USA
- U.S. Laser
- Valley Media (distributor)
- VCA Interactive (VCA Pictures, VCA
Labs; adult)
- VCI Home Video
- Ventura
- Victor Entertainment (JVC)
- Victory
- Video Watchdog
- Vidmark
- Vista Street
- Vivid Video (adult)
- Walt Disney Pictures
- Warner Bros. Records/Warner Music (Toshiba partner)
- Warner Home Video (Toshiba partner)
- Waterbearer Films
- WIT Entertainment (distributor)
- WGBH
- WWF Home Video
- Wolfe
- World Video
- Xenon
- Xoom
- York
DVD File maintains a list of studio addresses, as
well as DVD
producer and distributor information.
- Acer Laboratories: DVD decoder/controller chips
- Advent: DVD-ROM-equipped computers
- Alliance Semiconductor: display adapters with hardware acceleration for
DVD playback
- Allion: DVD mirroring servers
- AMLogic: DVD player chipset
- Analog Devices: 192-kHz/24-bit audio DAC
- Apple: DVD-ROM drives, DVD-ROM-equipped computers, software drivers,
playback hardware and software (QuickTime)
- ASACA: DVD-RAM towers
- AST: DVD-ROM-equipped computers (with MMX-based playback software)
- ASM: DVD jukeboxes
- ATI Technologies: display adapters with
hardware acceleration for DVD playback
- Avid Electronics: DVD decoder/controller chips
- Axis Communications: DVD-ROM storage
servers
- Bridge Technology: optical pickup
assemblies
- C-Cube: DVD encoder and decoder chips
- Canopus: DVD-RAM video archiving.
- CD Associates: Software and
hardware for production and testing.
- CEI: DVD playback hardware and software
- Cirrus Logic: display adapters with hardware acceleration for DVD playback
- Compaq: DVD-ROM-equipped computers
- Creative Technology: DVD-ROM and DVD-RAM upgrade kits, DVD decoder
software
- Cygnet: DVD-RAM jukeboxes
- DIC (Dainippon Ink and Chemicals): ink,
organic pigments, thermosetting resin
- Dave Jones Design: controllers for
industrial DVD players
- Diamond Multimedia: DVD upgrade kit (Toshiba drive)
- Digimarc: watermarking
technology
- Digital: DVD software playback (for Alpha workstations), DVD encoder chips
- Digital Stream: optical
pickup assemblie
- Digital Video Systems: DVD-ROM drives
- Disc, Inc.: DVD-RAM jukeboxes.
- DSM: DVD jukeboxes
- DVDO: video deinterlacing chips
- DynaTek: DVD upgrade kit
- EPO Technology: DVD-ROM drives
- Escient: DVD-ROM changer
- ESS Technology: playback chipset, player reference design
- Fantom Drives: DVD-RAM and
DVD-ROM kits
- Fujitsu: DVD-ROM-equipped computers
- Gateway: DVD-ROM-equipped computers
- Genesis Microchip: video
chips (progressive-scan, scaling)
- Granite Microsystems:
IEEE-1394 DVD-ROM drives
- Harman Int.: DVD jukebox
- Hitachi: DVD-ROM drives, decoder chips
- Hi-Val: DVD playback hardware (upgrade kit)
- Hyundai: DVD decoder chips
- IBM: DVD-ROM-equipped computers, decoder chips
- I-Jam: DVD-ROM drives
- Imation: DVD-RAM media.
- Inaka: DVD jukebox software
- Infineon: DVD reader circuitry
- Innovacom: DVD encoder and decoder systems
- Intel: DVD playback hardware (MMX) and software
- Interactive Seating: Battle
Chair
- I/OMagic: IEEE-1394 DVD-ROM drives
- JVC: DVD-ROM drives, DVD-RAM jukebox
- Kasan: decoder hardware
- KOM: DVD-RAM changer
- LaCie: DVD-RAM drives
- Leitch: DVD-RAM video recording
- LG Electronics: DVD-ROM drives
- LSI: DVD decoder chips and playback cards
- Luminex: Unix software for DVD-based
archiving and duplication
- LuxSonor: DVD playback chips
- Margi: DVD decoder card for notebook PCs
- Matrox: display adapters with hardware acceleration for DVD playback
- Matsushita (Panasonic): DVD-ROM drives, upgrade kits, DVD/Web integration,
DVD-RAM still-image recorder
- Media100: DVD authoring tools, DVD
playback hardware and software
- Mediamatics: DVD playback software and hardware
- Medianix: Dolby Digital decoder hardware with Spatializer 3D audio
- Memorex: DVD-ROM drives
- Microboards: DVD drive (VAR)
- Microsoft: DVD drivers and playback software (DirectShow)
- Microtest: DVD-ROM jukeboxes
- Mitsubishi: DVD-ROM drives
- Motorola: DVD decoder chips
- National Semiconductor: DVD playback and reference designs
- Number 9: display adapters with hardware acceleration for DVD playback
- NEC: DVD-ROM drives
- Net TV: DVD-ROM PC for home
entertainment
- NSM: DVD-ROM jukebox, DVD-RAM jukebox
- Oak Technology: DVD playback hardware and software
- OTG Software: DVD jukebox software
- Packard Bell: DVD-ROM-equipped computers
- Philips: DVD-ROM drives, decoder chips
- Pioneer: DVD-ROM drives
- Plasmon Data: DVD-RAM jukebox
- Procom: DVD-ROM jukebox
- Ravisent (formerly Quadrant
International): DVD-Video decoding hardware and software
- Ricoh: DVD-ROM/CD-RW drives
- RITEK: DVD-R, DVD-RAM
- S3: display adapters with hardware acceleration for DVD playback
- Samsung: DVD-ROM drives and DVD-ROM-equipped computers
- Spectradisc: limit-play
technology
- STMicroelectronics (formerly
SGS-Thomson): DVD decoder chips
- SICAN: DVD decoder chips
- Sigma Designs: DVD playback hardware
- Software Architects: DVD-recordable software (w/Elektroson)
- Sony: DVD-ROM drives and DVD-ROM-equipped computers
- STB Systems: DVD playback hardware (upgrade kit)
- Stream Machine: MPEG-2
encoder/decoder chips
- TDK: blank DVD-RAM discs
- Toshiba: DVD-ROM drives and DVD-ROM-equipped computers
- Tracer Technologies: DVD jukebox
software and DVD recording software (Unix)
- TribeWorks: custom player
software
- Trident Microsystems: DVD decoder chips, DVD-accelerated video controller
chips
- Truevision: DVD playback software (Microsoft Active Movie 2.0)
- Verbatim Australia (ActiveMedia): DVD playback hardware (upgrade kit)
- VisionTech: MPEG-2
encoder/mulitplexer
- VM Labs: DVD playback reference
platform (Nuon)
- Wired: DVD playback hardware and
software (acquired by Media 100)
- X-10.com: (wireless DVD transmitter)
- Xing: DVD playback software
- Yamaha: AC-3 decoder chips
- Zen: multi-beam DVD reading technology
- Zoran/CompCore: DVD software and hardware playback, DVD decoder chips
- 2 Way Media: Launch
- Access Software: Overseer,
Tex Murphy
- Acclaim Entertainment: Reah
- Accolade: Jack Nicklaus 4, Family Spectacular
- Action Zone: games
- Activision (Quicksilver): Muppet Treasure Island, Spycraft: The Great
Game, Zork: The Grand Inquisitor
- Aftermath Media: Tender
Loving Care
- ALLDATA: automotive information databases
- Aludra: Beat 2000 DVD, Language Tutor
DVD, Virtual Makeover DVD
- Apple Computer: Mac OS Anthology
(available to developers only)
- BBC Interactive
- Black Isle Studios (Interplay):
Baldur's Gate
- Broderbund: Riven
- Byron Preiss/Simon &
Schuster: The Timetables of Technology
- ComChoice: Marketing, sales, and
training
- Creative Multimedia:
Billboard Music Guide, Blockbuster Entertainment Guide to Movies and Video
- Creative Wonders (The
Learning Company): Schoolhouse Rock, Sesame Street, Wide World of Animals
- DeLorme: AAA Map'n'Go DVD Deluxe
- Data Becker: Clipart Collection, Sound Collection
- Digital Directory Assistance:
PhoneDisc PowerFinder USA One
- Digital Versatile Disc:
Shaodan
- Digital Leisure: Dragon's
Lair, Hologram Time Traveler, Space Ace
- Discovery Channel: Leopard
Son/Animal Planet, Connections
- Dorling Kindersley
- Electronic Arts: Wing Commander IV
- Firebrand: Lost in Crazy Town
- genX Software: Dead Moon
Junction
- Global Star Software: 100
Great Action Arcade Games, Excessive Speed, Gubble, 303 Professional Legal
Forms
- Graphix Zone
- Grolier: Multimedia Encyclopedia
- GT Entertainment: Forrest Gump, Reah
- Hachette Multimedia:
Hachette Encyclopedia
- IBM Interactive Media: The Pistol: The Birth of a Legend
- Index+: Dracula Resurrection,
Dracula the Last Sanctuary, Louvre the Final Curse
- Interactual Technologies: Star
Trek VideoSaver
- Interplay: Baldur's Gate,
Starfleet Academy
- Into Networks: PlayNow (unlockable
games)
- IVS: The Union Catalogue of Belgian Research Libraries
- Japan Travel Bureau: DVD-Web product
- The Learning Company (SoftKey): Battles of the World, Clickart, Digital
Library, The Genius of Edison, National Geographic, Printmaster 7.
- Liris (Havas) Interactive: Découvertes (Junior Discovery)
- Magnum Design
- Mechadeus: The Daedalus Encounter
- MediaGalleries: Multimedia
Bach
- MediaOne: VersaDisc
- Microsoft: Encarta, MSDN/TechNet,
Works Suite
- Mill Reef: Earthlight, Coral Sea
Dreaming
- Mindscape
- Mitchell Repair Information
Company: ON-DEMAND
- Monolith: Claw
- Montparnasse Multimedia:
Microcomsos, Voyage to the land of the Pharaohs
- Multimedia 2000 (aka M-2K, formerly
Multicom): Birds of the World; Bubblegum Crisis; HomeDepot's Home Improvement
1-2-3; Warren Miller's Ski World '97; Exploring National Parks; Great Chefs,
Great Cities; Better Homes and Gardens Cool Crafts
- Natif
- NB Digital/Mill Reef: Earthlight
- Not A Number: Blender
- Oeil Pour Oeil: Death Dealer
- Organa: The Book of Lulu
- Pro CD: Select Phone
- Project Two Interactive: Reah
(distributed by GT in U.S., Acclaim in UK and Ireland)
- Psygnosis
- Red Orb Entertainment:
- Sega: 4 game/instruction titles to be
released in early 1997
- Sierra Online
- Sumeria: Vanishing Wonders of the
Sea, Wild Africa
- SuperZero: adult DVD-Video
- SuSE: SuSE Linux 6.3
- TerraGlyph Interactive Studios:
Buster and the Beanstalk (Tiny Toons)
- Torus Games
- Tsunami: Crazy 8's, Silent Steel, Silent Steel II
- VR Sports (Interplay): Virtual Pool
- Warner Advanced Media
- Westwood Studios: Command & Conquer
- Xiphias: Encyclopedia Electronica
- Zombie VR Studios: Liberty
- 800.com
- A&B Sound (Canada)
- abcDVD (UK, region
1)
- AccessDVD.com
- Ace VCD DVD (Hong Kong/anime)
- Airplay (Japan, region
2)
- All DVD Movies
- Amazon.com
- Amazon.co.uk
(UK)
- AnimeNation
- Anime Depot
- Asian Xpress (Hong Kong films)
- Best Buy
- Best Buy Movie (Germany)
- Beyond Music
- Big Emma (used discs)
- BigStar
- Blockbuster (rental and sales)
- Brainplay.com
- Buy.com
- C&L Internet Club (Canada)
- Canyon Street (France, region 1
and 2)
- CD JAPAN (Japan, region 2)
- CDNOW
- CDRealm (Switzerland)
- Checkout.com
- Columbia House (DVD mailorder
club)
- Digibuster Media (online rental)
- Digital Entertainment (Indian
films)
- Digital Eyes
- Digital Playtime (Australia, region
4)
- The Digital Shop (Greece)
- Direct Video
- Disc and Picture Company
(Australia)
- discShop.com (UK,
region 1 and 2)
- DVDCity
- DV Depot
- DVD Domain
- DVD Empire
- DVD
EXPRESS
- DVDIt Italia (Italy)
- DVD North (Canada)
- DVDONE
- DVD Overnight (online rental)
- DVD Palace (formerly Liquidata)
- DVDPlus (Europe)
- DVD Rent (Australia, sales and
online rental)
- DVDstreet (region 2)
- DVD Wave
- DVD World (UK, region 2)
- DVD World (New Zealand, regions 1
and 4)
- DVD Zone 2 (region 2)
- Elvic (Netherlands)
- Evolution Audio & Video
- Fantastic Movies
(Switzerland)
- Fotosound (UK)
- German Music Express (Germany)
- Just Watch It (regions 1 and 2)
- Karaoke - Show (Switzerland)
- LADA Universal
(regions 1 and 2, new and used)
- Laser Corner (Greece)
- Laserdisc DVD Outlet
- Laser Discovery (online
rental, Hong Kong movies)
- The LaserDisc Division
- Laserdisc House (UK,
regions 1 and 2)
- Laser's Edge
- Laservisions Direct
- GoDVD (UK, regions 1 and 2)
- Hifi.com
(players)
- InsideDVD (free disc subscription)
- Hollywood Video (rental)
- Ken Crane's
- Kotiteatteri (Finland)
- Media Play
- MegaDVD
- Musicland
- NetFlix (online rental)
- On Cue
- OneCall (players)
- OZDVD Warehouse (region 4)
- Reel.com
- Reg2.net (Spain)
- Rent A DVD (online rental,
Switzerland)
- Ro-Disc (Netherlands, regions 1 and 2)
- RPM Records (rare discs)
- Sam Goody
- Second Chance DVD (used)
- Shopping.com
- Shopping Matrix (South Africa,
region 2)
- Stardust DVD (Puerto Rico)
- Starship Industries
- SublimeDigital.com (players
and drives)
- SVS (UK, region
2)
- Swinging Planet (UK, cult
video; region 2)
- Trans World Entertainment (TWEC)
- Universe of Entertainment (Switzerland)
- VideoCave
- VideoLtd.com
- Virgin Megastore
- Xchangecity (trade DVDs with
other members)
For local DVD rental outlets, see the list at DVD Post.
You can search for lowest prices and online discount coupons at DVD Price Search and DiVerse DVD.
Here are a few of the top DVD info sites.
- Robert's DVD Info: <www.unik.no/~robert/hifi/dvd/>
(tons of links to news articles and other pages)
- UK DVD FAQ: <movieuk.com/dvdfaq.htm>
(UK-specific DVD info)
- Ask Digital Man: <http://www.askdigitalman.com/>
(DVD tech support)
- Home Theater Forum: <http://www.hometheaterforum.com/>
(general DVD discussions)
- DVD Infomatrix: <http://www.inmatrix.com/> (a wealth of
information about DVD PCs)
- 7thZone: <http://www.7thzone.com/> (PC utilities,
software player reviews, region-free info, tech support, more)
- Michael D's Guide to Region 4
DVDs (review and other info on region 4 discs)
- Chad Fogg's technical notes: <www.mpeg.org/~tristan/MPEG/DVD/>
- Quantel Digital Fact Book (digital video info and glossary): <www.quantel.com/dfb>
- DVD for not-so-Dummies, from Technicolor <www.technicolor.com/services/DVD2000v1.pdf>
- DVD Primer, from Sonic Solutions <www.dvdcreator.com/pdf/dvd_primer.pdf>
- Tristan's MPEG Pointers and Resources <http://www.mpeg.org/>
- DVD discussion list. Send "subscribe DVD-L <your name>" to listserv@listserv.temple.edu
- For details on YUV, RGB, YCbCr, etc., read Charles Poynton's Color FAQ (or buy
his book).
You might also want to take a look at the book DVD Demystified, by the
author of this FAQ. More info at <dvddemystified.com>.
(If you know the answer to any of these, please speak up!)
- Are there official designations for 8 cm discs (DVD-1, DVD-2, etc.?)
- What do the D1, D2, etc. markings on some discs mean?
There's an unfortunate confusion of units of measurement in the DVD world.
For example, a single-layer DVD holds 4.7 billion bytes (G bytes), not 4.7
gigabytes (GB). It only holds 4.38 gigabytes. Likewise, a double-sided,
dual-layer DVD holds only 15.90 gigabytes, which is 17 billion bytes.
The problem is that the SI
prefixes "kilo," "mega," and "giga" normally represent multiples of 1000 (10^3,
10^6, and 10^9), but when used in the computer world to measure bytes they
generally represent multiples of 1024 (2^10, 2^20, and 2^30). Both Windows and
Mac OS list volume capacities in "true" megabytes and gigabytes, not millions
and billions of bytes
Most DVD figures are based on multiples of 1000, in spite of using notation
such as GB and KB/s that traditionally have been based on 1024. The "G bytes"
notation does seem to consistently refer to 10^9. The closest I have been able
to get to an unambiguous notation is to use "kbps" for thousands of bits/sec,
"Mbps" for millions of bits/sec, "kilobytes" for 1024 bytes, "megabytes" for
1,048,576 bytes, "gigabytes" for 1,073,741,824 bytes, and "BB" for 1,000,000,000
bytes.
This may seem like a meaningless distinction, but it's not trivial to someone
who prepares 4.7 gigabytes of data (according to the OS) and then wastes a DVD-R
or two learning that the discs really hold only 4.4 gigabytes!
To make things worse, data transfer rates when measured in bits per second
are almost always multiples of 1000, but when measured in bytes per second are
sometimes multiples of 1024. For example, a 1x DVD drive transfers data at 11.08
million bits per second (Mbps), which is 1.385 million bytes per second, but
only 1.321 megabytes per second. The 150 KB/s 1x data rate commonly listed for
CD-ROM drives is "true" kilobytes per second, since the data rate is actually
153.6 thousand bytes per second.
In December 1998, the IEC produced new
prefixes for binary multiples: kibibytes (KiB), mebibytes (MiB), gibibytes
(GiB), tebibytes (TiB), and so on. (More details at NIST.) These prefixes
may never catch on, or they may cause even more confusion, but they are a
valiant effort to solve the problem. The big strike against them is that they
sound a bit silly.
This FAQ is written and maintained by Jim Taylor. The following people have
contributed to the FAQ (either directly, by posting to alt.video.dvd, or by me
borrowing from their writing :-). Their contributions are deeply appreciated.
Information has also been taken from material distributed at the April 1996 DVD
Forum, May 1997 DVD-R/DVD-RAM Conference, and October 1998 DVD Forum
Conference.
Robert Lundemo Aas
Adam Barratt
David Boulet
Espen Braathen
Wayne
Bundrick
Roger Dressler
Chad Fogg
Dwayne Fujima
Robert "Obi"
George
Henrik "Leopold" Herranen
Irek Defee
Kilroy Hughes
Ralph
LaBarge
Martin Leese
Dana Parker
Eric Smith
Steve
Tannehill
Geoffrey Tully
Thanks to Videodiscovery for
hosting this FAQ for the first two and a half years.
----
Copyright 1996-2000 by Jim Taylor. This document may be redistributed only in
its entirety with version date, authorship notice, and acknowledgements intact.
No part of it may be sold for profit or incorporated in a commercial document
without the permission of the copyright holder. Permission will be granted for
complete electronic copies to be made available as an archive or mirror service
on the condition that the author be notified and that the copy be kept up to
date. This document is provided as is without any express or implied
warranty.
[End]
