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Path: senator-bedfellow.mit.edu!dreaderd!not-for-mail
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Expires: 29 Mar 2000 10:48:14 GMT
X-Last-Updated: 2000/02/14
From: jtfrog@usa.net (Jim Taylor)
Newsgroups: rec.video.dvd.advocacy,rec.video.dvd.misc,rec.video.dvd.tech,rec.answers,news.answers
Followup-To: rec.video.dvd.misc
Subject: rec.video.dvd Frequently Asked Questions (FAQ)
Keywords: DVD,FAQ
Summary: Frequently asked questions (with answers) about the DVD format, including DVD-ROM and DVD-Video.
Organization: DVD Demystified
Approved: news-answers-request@MIT.EDU
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Archive-name: rec-video/dvd-faq
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Last-modified: Oct 4, 1990
URL: http://www.dvddemystified.com/dvdfaq.html
Maintainer: Jim Taylor <jtfrog@usa.net>
DVD FAQ
DVD Frequently Asked Questions (and Answers)
This is the February 9, 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>.
------------------------------------------------------------------------
Contents
* [0] Where can I get the DVD FAQ?
* [0.1] Has the DVD FAQ been translated into other languages?
* [0.2] This FAQ is too long and technical. Is there a simpler
version?
* [0.3] Is this FAQ any good? How do I know it's accurate?
* [1] General DVD
* [1.1] What is DVD?
* [1.2] What are the features of DVD-Video?
* [1.3] What's the quality of DVD-Video?
* [1.4] What are the disadvantages of DVD?
* [1.5] What DVD players and drives are available?
* [1.5.1] Which player should I buy?
* [1.6] What DVD titles are available?
* [1.7] How much do players and drives cost?
* [1.8] How much do discs cost?
* [1.9] How quickly will DVD become established?
* [1.10] What are "regional codes," "country codes," or "zone
locks"?
* [1.11] What are the copy protection issues?
* [1.12] What about DVD-Audio or Music DVD?
* [1.13] Which studios are supporting DVD?
* [1.14] Can DVD record from VCR/TV/etc?
* [1.15] What happens if I scratch the disc? Aren't discs too
fragile to be rented?
* [1.16] VHS is good enough, why should I care about DVD?
* [1.17] Is the packaging different from CD?
* [1.18] What's a dual-layer disc? Will it work in all players?
* [1.19] Is DVD-Video a worldwide standard? Does it work with NTSC,
PAL and SECAM?
* [1.20] What about animation on DVD? Doesn't it compress poorly?
* [1.21] Why do some discs require side flipping? Can't DVDs hold
four hours per side?
* [1.22] Why is the picture squished, making things look too
skinny?
* [1.23] Do all videos use Dolby Digital (AC-3)? Do they all have
5.1 channels?
* [1.24] Can DVDs have laser rot?
* [1.25] Which titles are pan & scan only? Why?
* [1.26] How do I make the subtitles on my Pioneer player go away?
* [1.27] What is a layer change? Where is it on specific discs?
* [1.28] The disc says Dolby Digital. Why do I get 2-channel
surround audio?
* [1.29] Why doesn't the repeat A-B feature work on some discs?
* [1.30] What's the difference between first, second, and third
generation DVD?
* [1.31] What's a hybrid DVD?
* [1.32] What's the deal with DTS and DVD?
* [1.33] Why is the picture black and white?
* [1.34] Why are both sides fullscreen when one side is supposed to
be widescreen?
* [1.35] Why are the audio and video out of sync?
* [1.36] Why does the picture alternate between light and dark?
* [1.37] How do I find "Easter eggs" and other hidden features?
* [1.38] How do I get rid of the black bars at the top and bottom?
* [1.39] How should I clean and care for DVDs?
* [1.40] What's a progressive DVD player?
* [1.41] Why doesn't disc X work on player Y?
* [1.42] How do the parental control and multi-ratings features
work?
* [1.43] Which discs include multiple camera angles?
* [2] DVD's relationship to other products
* [2.1] Will DVD replace VCRs?
* [2.2] Will DVD replace CD-ROM?
* [2.3] Can CD-R writers create DVDs?
* [2.4] Is CD compatible with DVD?
* [2.4.1] Is CD audio (CD-DA) compatible with DVD?
* [2.4.2] Is CD-ROM compatible with DVD-ROM?
* [2.4.3] Is CD-R compatible with DVD-ROM?
* [2.4.4] Is CD-RW compatible with DVD?
* [2.4.5] Is Video CD compatible with DVD?
* [2.4.6] Is Super Video CD compatible with DVD?
* [2.4.7] Is Photo CD compatible with DVD?
* [2.4.8] Is CD-i compatible with DVD?
* [2.4.9] Is Enhanced CD compatible with DVD?
* [2.4.10] Is CD+G compatible with DVD?
* [2.4.11] Is CDV compatible with DVD?
* [2.4.12] Is MP3 compatible with DVD?
* [2.4.13] Is HDCD compatible with DVD?
* [2.5] Is laserdisc compatible with DVD?
* [2.6] Will DVD replace laserdisc?
* [2.7] How does DVD compare to laserdisc?
* [2.8] Can I modify or upgrade my laserdisc player to play DVD?
* [2.9] Does DVD support HDTV (DTV)? Will HDTV make DVD obsolete?
* [2.10] What was Divx?
* [2.11] How can I record from DVD to videotape?
* [2.12] Will high-definition DVD or 720p DVD make current players
and discs obsolete?
* [3] DVD technical details
* [3.1] What are the outputs of a DVD player?
* [3.2] How do I hook up a DVD player?
+ [3.2.1] Will I have problems connecting my VCR between my TV
and my DVD player?
* [3.3] What are the sizes and capacities of DVD?
+ [3.3.1] When will double-sided, dual-layer discs (DVD-18) be
available?
* [3.4] What are the video details?
* [3.5] What's widescreen? How do the aspect ratios work?
* [3.6] What are the audio details?
+ [3.6.1] DVD-Audio details
+ [3.6.2] Audio details of DVD-Video
* [3.7] How do the interactive features work?
* [3.8] What is the difference between interlaced and progressive
video?
* [3.9] What is edge enhancement?
* [3.10] Does DVD work with barcodes?
* [4] DVD and computers
* [4.1] Can I play DVD movies on my computer?
* [4.2] What are the features and speeds of DVD-ROM drives?
* [4.3] What about recordable DVD: DVD-R, DVD-RAM, DVD-RW, and
DVD+RW?
* [4.4] Why can't I take a screenshot of DVD video? Why do I get a
pink or black square?
* [4.5] Why can't I play movies copied to my hard drive?
* [4.6] Why do I have problems playing DVDs on my computer?
* [4.7] Can I stream DVD over a network or the Internet?
* [4.8] What is DeCSS?
* [4.9] How do I play DVD video in HTML, PowerPoint, Director, VB,
etc.?
* [4.10] What are .IFO, .VOB, and .AOB files? How can I play them?
* [5] DVD production
* [5.1] How much does it cost to produce a DVD? Isn't it more
expensive than videotape, laserdisc, and CD-ROM?
* [5.2] What DVD-ROM formatting tools are available?
* [5.3] What MPEG-2 encoding tools are available?
* [5.4] What DVD-Video production tools are available?
* [5.5] Who can produce a DVD for me?
* [5.6] What testing/verification services and tools are available?
* [5.7] Can I put DVD-Video content on a CD-R or CD-RW?
* [5.8] How do I copy my home videos to DVD?
* [5.9] How do I get a job making DVDs?
* [6] Miscellaneous
* [6.1] Who invented DVD and who owns it? Whom to contact for
specifications and licensing?
* [6.2] Who is making or supporting DVD products?
* [6.3] Where can I buy (or rent) DVDs and players?
* [6.4] Where can I get more information about DVD?
* [7] Leftovers
* [7.1] Unanswered questions
* [7.2] Notation and units
* [7.3] Acknowledgments
------------------------------------------------------------------------
Recent changes:
* 00-02-09: Removed flipper and layer-switch lists. Link to DVD Review's
Film Vault instead. (1.21, 1.27)
* 00-02-08: Note about Macrovision problems on TV/VCR combos. (3.2.1)
* 00-02-08: New question: [4.10] What are .IFO, .VOB, and .AOB files?
How can I play them?
* 00-02-07: DVD-R split into two versions, brining the number of DVD
recordable formats to five. (4.3)
* 00-02-07: Pioneer DVD-Audio players support SACD, which means there
may never be a "standards battle". (1.12)
* 00-02-01: New question: [1.43] Which discs include multiple camera
angles?
* 00-02-01: Link to Michael D's Guide to Region 4 DVDs. (6.4)
* 00-01-28: New question: [4.9] How do I play DVD video in HTML,
PowerPoint, Director, VB, etc.?
* 00-01-27: Rambling lists of PC decoders are now more-legible bulleted
lists. (4.1)
* 00-01-26: List of multi-rating and multi-version discs. (1.42)
* 00-01-26: Link to Dan Ramer's anamorphic article at DVD File. (3.5)
* 00-01-25: DVD hardware playback coming to Linux. (4.1)
* 00-01-25: Emphasis that letterbox and fullscreen images are usually
the same size. (1.38)
* 00-01-25: DeCSS stuff moved to its own new section: [4.8] What is
DeCSS?
* 00-01-25: Revised description of CSS. (1.11)
* 00-01-25: Note that region codes could be considered an illegal
restraint of trade. (1.10)
* 00-01-25: Pointer to excellent CD-i FAQ. (2.4.8)
* 00-01-25: Pointers to information on DVD mastering and replication.
(5.0)
* 00-01-25: New question: [3.10] Does DVD work with barcodes?
* 00-01-24: The DeCSS saga continues: Norwegian hacker raided.
Preliminary injunctions granted in NY and CA suits. (4.8)
* 00-01-24: A bunch of questions to help you pick a player. (1.5.1)
* 00-01-17: DeCSS source code available on a T-shirt. (4.8)
* 00-01-15: More on DVD video recorders. Rewritten DVD+RW section (pun
intended). (4.3)
* 00-01-15: More DeCSS lawsuits. (4.8)
* 00-01-15: More links to software players. (4.1)
* 00-01-15: More manufacturers and more Web site links. (6.2)
* 00-01-14: New question: [0.3] Is this FAQ any good? How do I know it's
accurate? (Moved section 1.1.1 to 0.2)
* 00-01-14: Link to DVD Utils Web site. (6.4)
* 00-01-13: New question: [2.12] Will high-definition DVD or 720p DVD
make current players and discs obsolete?. Related reworking of HDTV
section (2.9).
* 00-01-09: Minor revisions to video resolution info. Moved analog
signal figures from laserdisc section to video section. (3.4)
* 00-01-09: TVGuardian option for parental control. (1.42)
* 00-01-08: Many additions and URLs of DVD companies. (6.2)
* 00-01-05: New address for Russian translation. (0.1)
* 00-01-05: Difference between PAL and SECAM DVD players. (1.19)
* 99-12-29: DVD CCA restraining order denied. (4.8)
* 99-12-29: DVD CCA created to license CSS. (6.1)
* 99-12-27: More YUV-RGB converter sources. (3.1)
* 99-12-27: New question: [1.5.1] Which player should I buy?
* 99-12-19: More infrared remotes for DVD playback on PCs. (4.1)
* 99-12-19: Minor rewrites of video encoding section. (3.4)
* 99-12-19: More info on making MiniDVDs. (5.7)
* 99-12-18: A few more compatibility problems. (1.4.1)
* 99-12-18: Link to Home Theater Forum, an excellent DVD discussion
site, and DVD Infomatrix, a great source of info on DVD PCs. (6.4)
* 99-12-12: Some naughty discs and players don't use 4:3 letterbox flags
properly. (3.5)
* 99-12-12: Watch out for progressive-scan TVs that don't allow aspect
ratio changes. (1.40)
* 99-12-12: Updated info on DVD-Audio (delayed until mid 2000). (1.12)
* 99-12-12: Minor updates to DTS info. (1.32)
* 99-12-12: No need for regular alignment of laser in player. (1.39)
* 99-12-12: Not even Philips 170 can play DVD-V content from CD-R/RW.
(5.7)
* 99-12-11: Italian translation available at
http://digilander.iol.it/pierugo1/traduzione_faq_dvd.html.
* 99-12-11: New questions:
[1.42] How do the parental control and multi-ratings features work?
[3.9] What is edge enhancement?
[4.7] Can I stream DVD over a network or the Internet?
* 99-12-11: New troubleshooting step for PCs (overlay surface). (4.6)
* 99-12-11: Mentioned DVD-R replication for short runs. (5)
* 99-12-11: Layer change times for The Mummy, 12 Monkeys, Deer Hunter,
Apollo 13 (DTS), Legionnaire, A Simple Plan, Stargate SE, The Stand.
(1.27) Thanks Bob, Josh, Kristen, Shawn, Adam, Dream Master.
* 99-12-10: Numerous updates on writable DVD. (4.3)
* 99-11-19: First commercial DVD-18. (3.3.1) (A bit of gloating about my
accurate prediction.)
* 99-11-19: New question: [2.11] How can I record from DVD to videotape?
* 99-11-19: Software DVD player for Mac. (4.1)
* 99-11-19: Link to Aaron's rebuttal of Bernie's "Letterschlock FAQ."
(1.38)
* 99-11-15: New IEC prefixes for binary multiples. (7.2)
* 99-11-11: Visible Light authoring packages. (5.4)
* 99-11-09: New question: [6.3] Where can I buy (or rent) DVDs and
players?
* 99-11-08: CSS (copy protection) cracked. (4.8)
* 99-11-08: A few new DVD players can play MP3 CDs. (2.4.12)
* 99-11-03: New question: [1.1.1] This FAQ is too long and technical. Is
there a simpler version?
* 99-10-05: A few DVD players can read SVCD. Philips DVD170 is
upgradable. (2.4.6)
* 99-10-04: More about why so many DVDs are widescreen (is my bias
showing? :-), including links to sites with more info (1.38).
Additions to widescreen links at the end of 3.5.
------------------------------------------------------------------------
[0] Where can I get the DVD FAQ?
* The most current version is on the Web at
<http://www.dvddemystified.com/dvdfaq.html>.
* A text version is posted periodically as "rec.video.dvd Frequently
Asked Questions (FAQ)" to rec.video.dvd.tech, rec.video.dvd.misc,
rec.answers, news.answers, and other relevant newsgroups.
* Mirror copy locations include:
o U.S. (Digital Bits):
<http://www.thedigitalbits.com/officialfaq.html>
o U.S. (DVD Resource):
<http://www.dvdresource.com/dvdfaq/dvdfaq.shtml>
o DVD City <http://www.dvdcity.com/officialfaq.html> (optimized by
Adero for faster access in Australia France, Germany, Hong Kong,
Japan, Netherlands, Singapore, Spain)
o Ireland (DVDDirect): <http://www.dvddirect.ie/faq.html>
o Germany (Area DVD): <http://www.areadvd.de/dvdfaq.html>
o UK (DVD Guide): <http://216.71.152.46/DVDGuide/faq.htm>
o Sweden (DVD Registret):
<http://www.dvdregistret.com/dvdfaq/dvdfaq.html>
o Norway (DVDnett.no): <http://www.dvdnett.no/dvdfaq>
o South Africa (DVDSA):
<http://www.theshoppingmatrix.com/dvd/faq.asp>
o Netherlands (DVD-Info Point):
<http://www.dvdnews.nl/infofaq.html>
o Austria (dvd.at); <http://www.dvd.at/dvd/fact15a.htm>
o Australia (aus.dvd): <http://www.ozemail.com.au/~brierley/dvd>
* A text archive of the version last posted to newsgroups is at
<http://www.faqs.org/faqs/rec-video/dvd-faq> and other FAQ mirrors, as
well as <http://www.dvddemystified.com/dvdfaq.txt>. You can have a
text version of the FAQ emailed to you by sending email to
dvdfaq@dvdresource.com.
[0.1] Has the DVD FAQ been translated into other languages?
Various translations of the DVD FAQ are available:
* French <http://www.mygale.org/~abela/DVD/DVDfaq.html>. Merci beaucoup
to Zahir Abela.
* Italian <http://digilander.iol.it/pierugo1/traduzione_faq_dvd.html>.
Molti ringraziamenti to Pierugo Mazzaccheri.
* Japanese <http://www.dms.co.jp/dvd/dvdfaq_j.html>. Otsukaresama to
Yoshida Toshinori.
* Norwegian <http://www.dvdnett.no/dvdfaq/norsk/>. Tusen takk to Paul H.
Brekke and Lasse Hatletvedt.
* Russian <http://www.rusdvdportal.com/dvdfaq.htm>. Blagodara to
Alexander Lokshin.
* Spanish <http://club.idecnet.com/~modegar/video/dvdfaq.html>.
Muchisimas gracias to Modesto Garrido.
If you'd like to translate the DVD FAQ into another language (Klingon,
anyone?), please contact Jim.
[0.2] This FAQ is too long and technical. Is there a simpler version?
Try Earl's Famous DVD Technology Exposition Web Page Extravaganza Supreme
Deluxe (http://lonestar.texas.net/~bdub/earl/dvd.htm).
[0.3] Is this FAQ any good? How do I know it's accurate?
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.
------------------------------------------------------------------------
[1] General DVD
[1.1] What is DVD?
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 video as well as audio and computer data.
DVD aims to encompass home entertainment, computers, and business
information with a single digital format, eventually replacing audio CD,
videotape, laserdisc, CD-ROM, and perhaps even video game cartridges. DVD
has widespread support from all major electronics companies, all major
computer hardware companies, and 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 DVD-Video and DVD-ROM.
DVD-Video (often simply called DVD) holds video programs and is played in a
DVD player hooked up to a TV. DVD-ROM holds computer data and is read by a
DVD-ROM drive hooked up to a computer. The difference is similar to that
between Audio CD and CD-ROM. DVD-ROM also includes recordable variations
(DVD-R, DVD-RAM, DVD-RW, DVD+RW; see 4.3). Most people expect DVD-ROM to be
initially much more successful than DVD-Video. Most new computers with
DVD-ROM drives can also play DVD-Videos (see 4.1).
There's also the DVD-Audio format that was finalized in late 1999 but won't
be available outside of Japan until late 2000 at the earliest (see 1.23 and
3.6.1).
[1.2] What are the features of DVD-Video?
* 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.
* 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.
[1.3] What's the quality of DVD-Video?
DVD has the capability to produce near-studio-quality video and
better-than-CD-quality audio. DVD is vastly superior to videotape and
generally better than laserdisc (see 2.8.). However, quality depends on
many production factors. 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.
[1.4] What are the disadvantages of DVD?
* 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)
* Current players can't play in reverse at normal speed.
* Variations and options such as DVD-Audio, DTS audio tracks, and Divx
are not supported by all players.
[1.5] What DVD players and drives are available?
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:
* UK DVD FAQ and uk.media.dvd FAQ.
* aus.dvd (Australia/New Zealand/region 4 player info)
* WebShopper report on DVD-ROM drives (Sep 16, 1998)
[1.5.1] Which player should I buy?
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.
[1.6] What DVD titles are available?
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.
As of June 1999 there are about 3,500 titles available in the US and over
5,000 worldwide. Compared to other launches (CD, LD, etc.) this is a huge
number. Almost 19,000 discs were purchased in the first two weeks of the US
launch -- more than expected. InfoTech predicted over 600 titles by the end
of 1997 and more than 8,000 titles by 2000. By December 1997, over 1
million individual DVD discs were shipped. By June 1999, over 30 million
discs had shipped.
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 list of movie titles available in the US and
Canada see Jeff Phillips' list at <http://www.thedvdlist.com>. For titles
in Japan and Europe see Niels van Eijkelenburg's list at
<http://www.surroundfreak.com/dvd/dvd2.htm> or Robert's list at
<http://www.unik.no/~robert/hifi/dvd/film2.html>. Also check out the
Internet Movie Database's DVD Browser. Christoph Steinecke's extensive list
of region 1 titles is at <http://www.surroundfreak.com/dvd/dvd1.htm>. New
release lists and announcements are available at
<http://www.image-entertainment.com/laserv.html>. For a list of
widescreen-specific DVD titles, visit http://www.WidescreenReview.com>.
Concorde Video released a PAL-format 12 Monkeys in Germany at the end of
March 1997. They were threatened by Philips with a lawsuit for not
including a multichannel MPEG track, but the issue is now resolved (see
3.6).
DVD-ROM software will slowly appear. Approximately 50% of CD-ROM producers
have announced intentions to develop for DVD-ROM. See 6.2 for a list. Many
initial DVD-ROM titles are only be available as part of a hardware or
software bundle until the market grows larger. IDC 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.
[1.7] How much do players and drives cost?
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.
[1.8] How much do discs cost?
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.
[1.9] How quickly will DVD become established?
Not as fast as generally predicted, but faster than videotape, laserdisc,
and CD. By the end of 1997 over 500,000 DVD-Video players shipped
worldwide. 349,482 of these were in the US (with about 200,000 actually
sold into homes). About 600 DVD video titles were available in the US, with
over 5 million copies shipped and about 2 million sold. Around 330,000
DVD-ROM drives were shipped worldwide with about 1 million bundled DVD-ROM
titles. Only 60 DVD-ROM titles were available by the end of 1997, most of
them bundled with PCs or drive upgrade kits.
By the end of 1999, there were almost 5 million DVD-Video players in the
US, and about 30 million DVD PCs.
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.
Here's reality:
* 1997
o 347,000 DVD-Video players shipped in the U.S.
o 900 DVD-Video titles in the U.S.
* 1998
o 906,000 DVD-Video players shipped in the U.S. 1,253,000 total
player shipments since March 1997.
o 400 DVD-Video titles in Europe (135 movie and music titles).
o 3,000 DVD-Video titles in the U.S. (2000 movie and music titles).
o 7.2 million DVD-Video discs purchased.
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 are
about 80 million VCRs in the U.S. (89% of households) and about 400 million
worldwide. 110,000 VCRs shipped in the first two years after release.
Nearly 16 million VCRs were shipped in 1998. There are about 3 million
laserdisc players in the U.S. There are about 270 million TVs in the U.S.
and 1.3 billion worldwide.
[1.10] What are "regional codes," "country codes," or "zone locks"?
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, Middle East (including Egypt)
3: Southeast Asia, East Asia (including Hong Kong)
4: Australia, New Zealand, Pacific Islands, Central America, Mexico, South
America, Caribbean
5: Eastern Europe (Former Soviet Union), Indian Subcontinent, Africa (also
North Korea, Mongolia)
6: China
7: Reserved
8: Special international venues (airplanes, cruise ships, etc.)
(See the map at <http://www.unik.no/~robert/hifi/dvd/world.html>.)
Some players can be modified to play discs regardless of their regional
codes. This usually voids the warranty, but is probably not illegal. Some
discs, such as those from Buena Vista/Touchstone/Miramax, MGM/Universal,
and Polygram contain program code that checks for the proper region. These
"smart discs" won't play on code-free players that have their region set to
0, but they can be played on code-switchable players that allow you to
change the region using the remote control. They may also not work on
auto-switching players that recognize and match the disc region.
Information about modifying players can be found on the Internet (at sites
such as Code Free DVD, PlanetDVD, Techtronics, Upgrade Heaven, and
<http://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 are allowed for use only
with DVD-Video discs, not DVD-ROM discs containing computer software. (See
1.11 below for more details). Computer playback systems check for regional
codes before playing movies from a DVD-Video. Newer "RPC2" DVD-ROM drives
let you change the region code several times. Once a drive has reached the
limit (usually 5 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.
[1.11] What are the copy protection issues?
There are four forms of copy protection used by DVD:
1) Analog CPS (Macrovision)
Videotape (analog) copying is prevented with a Macrovision 7.0 or similar
circuit in every player. The general term is APS (Analog Protection
System). Computer video cards with composite or s-video (Y/C) output must
also use APS. Macrovision adds a rapidly modulated colorburst signal
("Colorstripe") along with pulses in the vertical blanking signal ("AGC")
to the composite video and s-video outputs. This confuses the
synchronization and automatic-recording-level circuitry in 95% of consumer
VCRs. Unfortunately, it can degrade the picture, especially with old or
nonstandard equipment. Macrovision may show up as stripes of color,
distortion, rolling, black & white picture, and dark/light cycling.
Macrovision creates severe problems for most line doublers. Macrovision is
not present on analog component video output of early players, but is
required on newer players (AGC only, since there is no burst in a component
signal). The discs contain "trigger bits" in the header of each sector
telling the player whether or not to enable Macrovision AGC, with the
optional addition of 2-line or 4-line Colorstripe. This allows fine control
over which sections are copy protected. The producer of the disc decides
what amount of copy protection to enable and then pays Macrovision
royalties accordingly (a few cents per disc). Just as with videotapes, some
DVDs are Macrovision-protected and some aren't. (For a few Macrovision
details see STMicroelectronics' NTSC/PAL video encoder datasheets at
<http://www.st.com/stonline/books/>.)
2) CGMS
Each disc also contains information specifying if the contents can be
copied. This is a "serial" copy generation management system (SCMS)
designed to prevent copies or copies of copies. The CGMS information is
embedded in the outgoing video signal. For CGMS to work, the equipment
making the copy must recognize and respect the CGMS. The analog standard
(CGMS/A) encodes the data on NTSC line 21 (in the XDS service). The digital
standard (CGMS/D) is not yet finalized, but will apply to digital
connections such as IEEE 1394/FireWire. See section 4, below.
3) Content Scrambling System (CSS)
Because of the potential for perfect digital copies, paranoid movie studios
forced a deeper copy protection requirement into the DVD 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, 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 Data-Hiding Sub-Group (DHSG) of the industry's Copy Protection
Technical Working Group (CPTWG) is evaluating watermarking proposals. The
original seven watermarking proposals that were merged into three: IBM/NEC,
Hitachi/Pioneer/Sony, and Macrovision/Digimarc/Philips. On February 17,
1999, the first two groups combined to form the "Galaxy Group" and merged
their technologies into a single proposal. Watermarking, which 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.
[1.12] What about DVD-Audio or Music DVD?
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. DVD-Audio products will show up in mid
2000. The delay is in part caused by the slow process of selecting copy
protection features (encryption and watermarking), with complications
introduced by the Secure Digital Music Initiative (SDMI). 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 technology was chosen in August (?) 1999. (In
November 1999, Verance watermarking was also selected for SDMI.) The
scheduled October release was delayed until mid 2000, ostensibly because of
concerns caused by the CSS crack (see 1.11), but also because the hardware
wasn't quite ready, production tools aren't up to snuff, and there is
lackluster support from music labels.
Matsushita's Panasonic and Technics universal DVD-Audio/DVD-Video players
will be available in mid 2000 and will cost $700 to $1,200. Yamaha may also
release DVD-Audio players at the same time.
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 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 required to use the full digital resolution of
DVD-Audio.
DVD audio is copyright protected by an embedding signalling 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
extensive test performed by the 4C indicate that even golden-eared
listeners can't detect the watermarking noise.
Sony and Philips have developed a competing Super Audio CD format. (See
3.6.1 for details.) SACD provides "legacy" discs that have two layers, one
that plays in existing CD players, plus a high-density layer for DVD-Audio
players. Ironically, initial price for these dual-layer discs will be
higher than for a standard CD plus a standard DVD. Sony released version
0.9 of the SACD spec in April 1998, the final version 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. Initial SACD releases are mixed in stereo, not
multichannel. A number of studios have announced that they will release
SACD titles by the end of 1999: Audioquest (2), DMP (5), Mobile Fidelity
Labs, Sony (40), Telarc (12), Water Lily Acoustics (2).
[1.13] Which studios are supporting DVD?
When DVD players became available in early 1997, Warner and Polygram were
the only major movie studios to release titles. Additional titles were
available from small developers. The other studios gradually joined the DVD
camp (see 6.2 for a full list, see 1.6 for movie info).
Dreamworks was the last significant studio to announce full DVD support.
Paramount, Fox, and Dreamworks initially supported only Divx, but in summer
1998 they each announced support for open DVD.
[1.14] Can DVD record from VCR/TV/etc?
Short Answer: Not yet, but soon. Pioneer and Philips 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: Price of blank discs initially will be $30 and up.
Real-time compression requires higher bit rates for decent quality,
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
variations of DVD (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.
[1.15] What happens if I scratch the disc? Aren't discs too fragile to be
rented?
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 section D.12 of
<http://icib.igd.fhg.de/icib/it/iso/cd_13818-2/read1.html>).
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
<http://home.earthlink.net/~tlfordham/rental.html>.
[1.16] VHS is good enough, why should I care about DVD?
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.
[1.17] Is the packaging different from CD?
Manufacturers are worried about customers assuming DVDs will play in their
CD player, so they would like the packaging to be different. There are a
number of DVD packages such as Amaray's "keep case" and Time Warner's
"Snapper" that are as wide as a CD jewel box and as tall as a VHS cassette
box. This meets the guidelines of 7-3/8" height x 5-5/8" width suggested by
the VSDA (Video Software Dealers association). However, no one is being
forced to use a larger package size and many companies will undoubtedly use
standard jewel cases. Divx discs came in jewel-case-sized paperboard and
plastic Q-Pack cases. It remains to be seen if any package becomes
standard, especially for DVD-ROM.
[1.18] What's a dual-layer disc? Will it work in all players?
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.)
[1.19] Is DVD-Video a worldwide standard? Does it work with NTSC, PAL, and
SECAM?
DVD-V has the same NTSC vs. PAL problem as videotape and laserdisc. The
MPEG video on DVD is stored in digital format, but it's formatted for one
of two mutually incompatible television systems: 525/60 (NTSC) or 625/50
(PAL/SECAM). There are three differences between discs intended for
playback on different systems: picture size and pixel aspect ratio (720x480
vs. 720x576), display frame rate (29.97 vs. 25), and surround audio (Dolby
Digital vs. MPEG). (See 3.4 and 3.6 for details.) Video from film is
usually stored at 24 frames/sec but is preformatted for one of the two
display rates. Movies formatted for PAL display are usually sped up by 4%,
so the audio must be adjusted accordingly before being encoded. All PAL DVD
players can play Dolby Digital audio tracks, but no NTSC players can play
MPEG audio tracks. 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 will only play NTSC discs, some players will only play PAL
discs, and some will play both. All DVD players sold in PAL countries play
both. These multi-standard players partially convert NTSC to a 60Hz PAL
(4.43 NTSC) signal, which requires a PAL TV that can handle 60-Hz signals.
In this case the player uses the PAL 4.43 MHz color subcarrier encoding
format but keeps the 525/60 NTSC scanning rate. Most modern PAL TVs can
handle this kind of signal. A few multi-standard PAL players output true
3.58 NTSC from 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. In 1999, Samsung and others released
standards-converting players 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
pseudo-PAL output with a compatible TV provides a better picture. A very
small number of NTSC players can play PAL discs. External converter boxes
are available, such as the Emerson EVC1595 ($350).
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 tracks
along with the MPEG audio tracks on their PAL discs.
There are actually three types of DVD players if you count computers. Most
DVD PC software and hardware can play both NTSC and PAL video and both
Dolby Digital and MPEG audio. Some PCs can only display the converted video
on the computer monitor, but others can output it as a video signal for a
TV.
[1.20] What about animation on DVD? Doesn't it compress poorly?
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.
[1.21] Why do some discs require side flipping? Can't DVDs hold four hours
per side?
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.)
[1.22] Why is the picture squished, making things look too skinny?
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.
[1.23] Do all videos use Dolby Digital (AC-3)? Do they all have 5.1
channels?
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.
[1.24] Can DVDs have laser rot?
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
http://www.mindspring.com/~yerington/.
[1.25] Which titles are pan & scan only? Why?
Some titles are available only in pan & scan because there was no letterbox
or anamorphic transfer made from film. (See 3.5 for more info on pan & scan
and anamorphic formats.) Since transfers cost $50,000 to $100,000, studios
may not think a new transfer is justified. In some cases the original film
or rights to it are no longer available for a new transfer. In the case of
old movies, they were shot full frame in the 1.37 "academy" aspect ratio so
there can be no widescreen version. Video shot with TV cameras, such as
music concerts, is already in 4:3 format.
The list of pan & scan only titles has gotten too big to keep here. You can
get a list from the Internet Movie Database (which also includes discs with
both widescreen and pan & scan versions), and you can search by screen
format (which includes disc with video shot in fullscreen 4:3) at The DVD
List.
[1.26] How do I make the subtitles on my Pioneer player go away?
On the remote control, press Subtitle, then either Clear or 0 (zero). No
need to use the menus.
[1.27] What is a layer change? Where is it on specific discs?
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.)
[1.28] The disc says Dolby Digital. Why do I get 2-channel surround audio?
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.
[1.29] Why doesn't the repeat A-B feature work on some discs?
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.
[1.30] What's the difference between first, second, and third generation
DVD?
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.
[1.31] What's a hybrid DVD?
Do you really want the answer to this one? Ok, you asked for it...
1. 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)
2. A DVD-ROM disc that runs on Windows and Mac OS computers. (More
accurately called a cross-platform DVD.)
3. 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.)
4. A disc that contains both DVD-Video and DVD-Audio content.
5. 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 9/99):
1. 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.
2. 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.
3. 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.
6. 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.)
7. A disc with two layers on one side and one layer on the other. (More
accurately called a DVD-14.)
8. A disc with an embedded memory chip for storing custom usage data and
access codes.
Did I miss any?
[1.32] What's the deal with DTS and DVD?
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).
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.
[1.33] Why is the picture black and white?
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.
[1.34] Why are both sides fullscreen when one side is supposed to be
widescreen?
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.
[1.35] Why are the audio and video out of sync?
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
1. Improper sync in audio/video encoding or DVD-Video formatting.
2. Poor sync during film production or editing (especially post-dubbing
or looping).
3. Loose sync tolerances in the player.
4. 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.
[1.36] Why does the picture alternate between light and dark?
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).
[1.37] How do I find "Easter eggs" and other hidden features?
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.
[1.38] How do I get rid of the black bars at the top and bottom?
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):
1. Check the other side of the disc (if it's two-sided)
2. Look for a fullscreen choice in the main menu
3. 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.
Note: Most widescreen movies use 1.85 ("flat") aspect ratio. 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 processed is used
(which cuts out parts of the picture). In other words, the picture is
usually 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 (1.85 movies),
or it allows the entire widescreen picture to visible (2.35 movies).
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.
[1.39] How should I clean and care for DVDs?
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.
[1.40] What's a progressive DVD player?
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 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.
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 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 players did a poor job of progressive-scan display of
DVDs, the first generation of progressive consumer players may be 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.
[1.41] Why doesn't disc X work in player Y?
[Note: this is a new section with a small list of compatibility problems to
start with. Please report other confirmed problems. Thanks.]
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. 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 a problem.
Below are problems reported by readers of this FAQ. The FAQ author has not
verified these claims and takes no responsibility for their accuracy.
Title Player Problem Solution
various
Polygram Early Toshiba and won't load or upgrade available from
titles Magnavox players freezes Toshiba service centers
various
Central Park
Media (anime) similar problems as The Matrix
titles
American Pie Philips 940 freezes at layer
change (1:17:09)
Arlington Road see Cruel Intentions
unplug player with disc
Armageddon Panasonic A115-U won't load inserted, plug in, turn
and A120-U
on
Toshiba SD-3108 locks up player upgrade available from
Avenger's TV Toshiba service centers
series (A&E) check with Philips for
Philips 930, 935 won't load
firmware upgrade
messes up reset the player or get
parental the corrected version
Cruel some JVC and controls, of the disc or set
Intentions Yamaha causing other parental country code
discs to not to AD with password of
play 8888
Deep Blue Sea similar problems as The Matrix
Toshiba upgrade available from
SD-2109/3109 various Toshiba service centers
Dragon's Lair check with Samsung
most Samsung,
Aiwa various (800-726-7864) or Aiwa
for firmware upgrade
Entrapment JVC freezes check with JVC for
firmware upgrade
Space Ace see Dragon's Lair
Sharp freezes
Lost In Space freezes, audio check for updated
Creative DXR3
out of sync drivers
details at PCFriendly
tech support
The Matrix various players various problems (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 distortion at
Ryan Toshiba SD-9000 end of ch. 4
freezes in
Stargate SE Magnavox 400AT director's
commentary
Tomorrow Never Sharp 600U locks up player
Dies Bush DVD2000 won't load
Universal picture breakup might be a problem with
Soldier Wharfedale 750 after ch. 30 the disc
Samsung DVD 709; check with Samsung
Wild Wild West Philips 930, 935; won't load (800-726-7864),
GE 1105P Philips, or GE for
firmware upgrade
You've Got details at PCFriendly
Mail various players various problems tech support
For 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.
[1.42] How do the parental control and multi-rating features work?
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 parental level so that discs rated above
that level will not play. As an alternative to a single rating for the
entire disc (or ratings for different sections of the disc), a disc can 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.
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 (1999 release), The Abyss, Independence Day, Terminator
2 (2000 release).
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, This allows
play lists to be created for the thousands of DVD movies that were produced
without parental control features. A number of projects are underway to
develop this type of software, but nothing is available yet.
Yet another option is TVGuardian, 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.
[1.43] Which discs include multiple camera angles?
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. King Crimson: Deja Vroom has excellent angles, allowing you to
focus on any of the musicians. Some movies, such as Ghostbusters SE,
Terminator 2 SE, and Tomorrow Never Dies SE use multiple angles in
supplements.
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).
------------------------------------------------------------------------
[2] DVD's relationship to other products
[2.1] Will DVD replace VCRs?
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.
[2.2] Will DVD replace CD-ROM?
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.
[2.3] Can CD-R writers create DVDs?
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.
[2.4] Is CD compatible with DVD?
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).]
[2.4.1] Is CD audio (CD-DA) compatible with DVD?
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.)
[2.4.2] Is CD-ROM compatible with DVD-ROM?
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.
[2.4.3] Is CD-R compatible with DVD-ROM?
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.
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 may be able to.
[2.4.4] Is CD-RW compatible with DVD?
Usually. CD-Rewritable (Orange Book Part III) has a lower reflectivity
difference, requiring new automatic-gain-control (AGC) circuitry. CD-RW
discs can't be read by most existing CD-ROM drives and CD players. The new
"MultiRead" standard addresses this, and some DVD manufacturers have
suggested they will support it. The optical circuitry in even
first-generation DVD-ROM drives and DVD players is usually able to read
CD-RW discs, since CD-RW does not have the "invisibility" problem of CD-R
(see 2.4.3).
Current writable DVD drives (see 4.3) can't record on CD-RW, although
future versions may be able to.
[2.4.5] Is Video CD compatible with DVD?
Sometimes. It's not required by the DVD spec, but it's trivial to support
the Video CD (White Book) standard since any MPEG-2 decoder can also decode
MPEG-1 from a Video CD. Panasonic, RCA, Samsung, and Sony models play Video
CDs. Japanese Pioneer models play Video CDs but American models older than
the DVL-909 don't. Toshiba players older than models 2100, 3107, and 3108
don't play Video CDs.
VCD resolution is 352x288 for PAL and 352x240 for NTSC. The way most DVD
players and Video CD players deal with the difference is to chop off the
extra lines or add blank lines. When playing PAL VCDs, the Panasonic and
RCA NTSC players apparently cut 48 lines (17%) off the bottom. The Sony
NTSC players apparently scale all 288 lines to fit.
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.
[2.4.6] Is Super Video CD compatible with DVD?
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 480x567
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.
[2.4.7] Is Photo CD compatible with DVD?
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.
[2.4.8] Is CD-i compatible with DVD?
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.
[2.4.9] Is Enhanced CD compatible with DVD?
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.
[2.4.10] Is CD+G compatible with DVD?
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.
[2.4.11] Is CDV compatible with DVD?
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.)
[2.4.12] Is MP3 compatible with DVD?
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 (KiSS, Monyka, Lasonic, Raite, Sampo, Shinco) can play MP3 CDs.
(See 6.2 for company Web sites.)
[2.4.13] Is HDCD compatible with DVD?
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.
[2.5] Is laserdisc compatible with DVD?
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.
[2.6] Will DVD replace laserdisc?
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.
[2.7] How does DVD compare to laserdisc?
* 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. Unlike CAV LD,
DVD can't play backwards (it's technically possible, but no current
players can do it).
* 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 has better quality on Dolby Surround soundtracks, which are
stored in uncompressed PCM format. DVD has better quality on Dolby
Digital or music only. 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
kHz. DVD LPCM audio can use 16, 20, or 24 bit samples at 48 or 96 kHz
(although PCM won't be 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 the same data rate (384
kbps) but can go up to 448 kbps for better quality, and can optionally
include DTS (at data rates up to 1536 kbps compared to LD's 1411 kbps,
but in practice DTS data rates will probably be lower on DVD than on
LD). DVD players convert Dolby Digital to Dolby Surround. This
conversion (downmix) process can reduce dynamic range. Combined with
the effects of compression, this usually 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,
especially at first, WILL be 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 ~= 500, LD
~= 425, and VHS ~= 240. 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
<http://www.cs.tut.fi/~leopold/Ld/FAQ/index.html>, and Bob Niland's FAQs
and overview at <http://www.frii.com/~rjn/laser/> (overview reprinted from
Widescreen Review magazine).
[2.8] Can I modify or upgrade my laserdisc player to play DVD?
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.
[2.9] Does DVD support HDTV (DTV)? Will HDTV make DVD obsolete?
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.
[2.10] What was Divx?
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 is offering $100 rebate coupons to all owners of Divx players.
This actually makes 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. 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).
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.
Disadvantages of Divx :
* Higher player cost (about $100 more).
* 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 ($4 to $7 vs. $2 to $3). 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.
* All 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.
* If your phone line were down for a long period of time, you might not
be able to watch Divx discs.
* 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.)
* Divx couldn't be used in mobile environments, such as a van or RV.
* 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.
For more information, see the Anti Divx page at
<http://www.dvdresource.com/divx>.
[2.11] How can I record from DVD to videotape?
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.
[2.12] Will high-definition DVD or 720p DVD make current players and discs
obsolete?
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 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.
See 2.9 for more information about HDTV and DVD.
------------------------------------------------------------------------
[3] DVD technical details
[3.1] What are the outputs of a DVD player?
Most DVD players have the following output connections:
Video:
- Composite video (CVBS) RCA (NTSC or PAL)
- Y/C (s-video) (NTSC or PAL)
Audio:
- Dual RCA stereo analog audio (with Dolby Surround encoding)
- Digital audio (IEC-958 Type II , EIAJ CP-340, EIAJ CP-1201) via RCA coax
(S/P DIF) or optical (Toslink). Raw digital audio (AC-3, PCM, MPEG-2, or
optional DTS or SDDS) requires an external decoder or an amplifier/receiver
with built-in decoder. (Note: The digital AC-3 audio output is not the same
as the RF AC-3 output on laserdisc players.)
Some players may have additional connections:
- Component interlaced analog video, NTSC or PAL (Y'PbPr: 3 RCA connectors,
RGB: SCART connector or 3 RCA).
- Component progressive analog video, NTSC or PAL (Y'PbPr, 3 connectors).
(Toshiba SD7108)
- RF video output for connecting via channel 3 or 4 to TV without direct
input. (Panasonic DVD-A300, RCA 5500P)
- 6 RCA jacks for analog surround sound output. (Panasonic DVD-A300, RCA
5500P, Samsung DVD905)
- AC-3 RF output on combo LD/DVD players. LD AC-3 on RF output only, DVD
AC-3 on coax/optical outputs only. (Pioneer DVL-90, DVL-700)
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
Midiman C02.
Some players can output 96/24 PCM audio using a non-standard variation of
IEC-958 running at 6.2 MHz (6.144 mpbs) instead of the normal limit of 3.1
MHz. Note: The DVD license restricts digital PCM output of CSS-protected
material to 48kHz/24-bit signals.
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 it's
expected that at some point digital output will be available using FireWire
(IEEE 1394) connectors.
[3.2] How do I hook up a DVD player?
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.
Video
* Progressive video (very best): A few players have progressive-scan YUV
(Y'Pb'Pr') or RGB (European players only) component video output in
the form of 3 BNC or RCA connectors. 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. This format preserves the
progressive nature of most 24-frame movie discs, providing a
film-like, flicker-free image with higher vertical resolution and
smoother motion. DVD computers also can provide progressive video from
DVD. 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 in the form of 3 RCA or BNC
connectors. 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 YCbCr.) Some players have RGB component
video output via a 20-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 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 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 (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
connectors may be labelled 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): A few players have RF video output for televisions
with only an antenna connection. Connect a coax cable from the player
to the TV. A 300 ohm to 75 ohm adapter may be needed. Tune the TV to
channel 3 or 4 and set the switch on the back of the player to match.
Audio is supplied with the RF signal, but it's only mono, even on
stereo TVs. If you have a player without RF output, you can buy an RF
modulator (~$30 at Radio Shack) to hook up to an old TV that only has
RF input. (See warning below about using a VCR as an RF modulator.)
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 signalling, 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.
Audio
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), DTS, and MPEG-2 audio. For Dolby Digital,
DTS, or MPEG-2, the appropriate decoder is required in the receiver or
as a separate audio processor. For PCM, a digital receiver or an
outboard DAC is required. 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 (PCM) output. 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 be bent much. 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.
[3.2.1] Will I have problems connecting my VCR between my TV and my DVD
player?
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.
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).
[3.3] What are the sizes and capacities of DVD?
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. 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), G means
billions of bytes (10^9). See note about giga vs. billion in section 7.2.
* DVD-5 (12cm, SS/SL): 4.38 gig (4.7 G) of data, over 2 hours of video
* DVD-9 (12cm, SS/DL): 7.95 gig (8.5 G), about 4 hours
* DVD-10 (12cm, DS/SL): 8.75 gig (9.4 G), about 4.5 hours
* DVD-14 (12cm, DS/ML): 12.33 gig (13.24 G), about 6.5 hours
* DVD-18 (12cm, DS/DL): 15.90 gig (17 G), over 8 hours
* DVD-1 (8cm, SS/SL): 1.36 gig (1.4 G), about half an hour
* DVD-2 (8cm, SS/DL): 2.48 gig (2.7 G), about 1.3 hours
* DVD-3 (8cm, DS/SL): 2.72 gig (2.9 G), about 1.4 hours
* DVD-4 (8cm, DS/DL): 4.95 gig (5.3 G), about 2.5 hours
* DVD-R (12cm, SS/SL): 3.68 gig (3.95 G)
* DVD-R (12cm, DS/SL): 7.38 gig (7.9 G)
* DVD-R (8cm, SS/SL): 1.15 gig (1.23 G)
* DVD-R (8cm, DS/SL): 2.29 gig (2.46 G)
* DVD-RAM (12cm, SS/SL): 2.40 gig (2.58 G)
* DVD-RAM (12cm, DS/SL): 4.80 gig (5.16 G)
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
<http://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 .4 um to
.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 recordable DVD (DVD-R and DVD-RAM).
[3.3.1] When will double-sided, dual-layer discs (DVD-18) be available?
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.)
[3.4] What are the video details?
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). Using the traditional (and rather
subjective) television measurement of "lines of horizontal resolution" DVD
can theoretically produce 540 lines on a standard TV (720/1.33) and 405 on
a widescreen TV (720/1.78). In practice, most DVD players provide about 500
lines because of filtering in the players and in the optics of telecine
equipment. VHS has about 230 (172 widescreen) lines and laserdisc has about
425 (318 widescreen). Note that lines of horizontal resolution (visually
resolvable vertical lines per picture height) are not the same as total
horizontal pixels (720) or horizontal scan lines (480). 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 (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 bitrate is 9.8 Mbps. The "average" bitrate is 3.5 but depends
entirely on the length, quality, amount of audio, etc. This is a 36:1
reduction from uncompressed 124 Mbps (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 limited to four pixel types. 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 the Closed Caption FAQ for
more about Closed Captions.
[3.5] What's widescreen? How do the aspect ratios work?
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
<http://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)
can be 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 European 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 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 will 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 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 The Big Squeeze: The ABCs of Anamorphic DVD article,
and Dan Ramer's What the Heck Is Anamorphic? article. There are excellent
animated illustrations at DVD Web (requires Flash). More information can be
found at the Anamorphic Widescreen Support Page.
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
[3.6] What are the audio details?
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.
[3.6.1] DVD-Audio details
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 up to 16 still graphics per track, 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.
[3.6.2] Audio details of DVD-Video
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 being the normal rate for 5.1
channels and 192 being the normal 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/document.html>. 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 bits. Both MPEG-1 and
MPEG-2 formats are supported. The variable bitrate 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 20 bits. The data rate is from 64 kbps to 1536 kbps, with typical
rates of 768 and 1536. (The DTS Coherent Acoustics format supports up to
4096 kbps variable data rate for lossless compression, but this isn't
supported by DVD.). Channel combinations are (front/surround): 1/0, 2/0,
3/0, 2/1, 2/2, 3/2. The LFE channel is optional with all 6 combinations.
The DVD standard includes an audio stream format reserved for DTS, but many
players ignore it. According to DTS, existing DTS decoders work with DTS
DVDs. 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
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.
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.
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. And so far, unlike on CDs and LDs, the level is much more
consistent between discs.
For more information about multichannel surround sound, see Bobby
Owsinski's FAQ at <http://www.surroundassociates.com/safaq.html>.
[3.7] How do the interactive features work?
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.
[3.8] What is the difference between interlaced and progressive video?
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 must be
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.
[3.9] What is edge enhancement?
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" filter 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.
[3.10] Does DVD work with barcodes?
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.
------------------------------------------------------------------------
[4] DVD and computers
[4.1] Can I play DVD movies on my computer?
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. 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 <http://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 ATI graphics cards
* ASUS: ASUSDVD
* 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)
* 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; PC-DVD
Encore Dxr2, C-Cube chip
* Digital Connection: 3DFusion, Mpact2 chip
* E4 (Elecede): Cool DVD, C-Cube chip (E4 has gone out of business)
* IBM: ThinkPad laptops, IBM chip
* LeadTek: WinFast 3D S800, Mpact2 chip
* Luxsonor: decoders in Dell PCs, C-Cube chip
* Margi: DVD-to-Go, ZV PC card for laptops
* QI: Hardware Cinemaster, C-Cube chip
* Philips Electronics: PCDV632, PCVD104, (K series come with Sigma
Hollywood card, R series come with software decoder)
* Sigma Designs: Hollywood series, Sigma EM8300 chip
* Samsung: Revolution, Samsung SD 606 6x, Sigma Hollywood Plus card
* STB: DVD Theater, Mpact2 chip
* Toshiba: Tecra laptops, C-Cube chip
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 http://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.
For remote control of DVD playback on your PC, check out Animax Anir
Multimedia Magic, 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.
[4.2] What are the features and speeds of DVD-ROM drives?
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. Most
1x DVD-ROM drives have a seek time of 90-200 ms and access time of 100-250
ms. 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 spin rate is about 3 times faster than CD (that is, 1x
DVD ~ 3x CD), but almost all DVD-ROM drives increase motor speed when
reading CD-ROMs, achieving 12x or faster performance. 2x DVD-ROM drives are
available (providing a transfer rate of 22.2 Mbps or 2.6 MB/s from DVDs,
equivalent to an 18x CD-ROM rate). Most 2x DVD-ROM drives read CD-ROMs at
20x (max) speeds and higher. 4x, 4.8x, 5x, 6x, 8x, and 10x drives are also
available, although they usually don't achieve a sustained transfer rate at
their full rating. A 5x drive can theoretically transfer data at 55.4 Mbps
or 6.4 MB/s, equivalent to a 45x CD-ROM data rate. Most 4x and faster
DVD-ROM drives read CD-ROMs at 32x (max).
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.
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.
[4.3] What about recordable DVD: DVD-R, DVD-RAM, DVD-RW, and DVD+RW?
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
<http://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 almost all DVD drives and players (the Sony DVP-S7000 and DVP-S3000
being notable exceptions). 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
will be 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
<http://www.ee.washington.edu/conselec/CE/kuhn/otherformats/95x9.htm> and
<http://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.
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 and is not
compatible with current drives (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 124.6mm x 135.5mm x 8.0mm.
DVD-RAM can be rewritten about 100,000 times, and the discs are expected to
last 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. 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 September (?) 1999. The first drives will appear in early 2000
at about the same price as current DVD-RAMime. 1.0 drives. 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 8cm 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: 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.
[4.4] Why can't I take a screenshot of DVD video? Why do I get a pink or
black square?
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.
[4.5] Why can't I play movies copied to my hard drive?
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".
[4.6] Why do I have problems playing DVDs on my computer?
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.
* 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.
More information on specific graphics cards and driver updates:
* Nvidia DVD Zone
* More to come...
[4.7] Can I stream DVD over a network or the Internet?
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.
The big problem is that CSS-encrypted movies (see 1.11) can't be remotely
sourced, since CSS requires that authentication and decryption be handled
locally, not over an accessible bus or network.
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 until after 2005. 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.]
[4.8] What is DeCSS?
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
http://www.emediapro.net/news99/news111.html), although other "ripping"
methods were available before that (see www.dvdutils.com, go.to/dvdsoft,
and 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 (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. 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
being 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 (possible only with specially modified drives), 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 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.
[4.9] How do I play DVD video in HTML, PowerPoint, Director, VB, etc.?
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.
[4.10] What are .IFO, .VOB, and .AOB files? How can I play them?
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.
------------------------------------------------------------------------
[5] DVD production
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.
[5.1] How much does it cost to produce a DVD? Isn't it more expensive than
videotape, laserdisc, and CD-ROM?
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 $120/min for video, $20/min for audio, $6/min for
subtitles, plus formatting and testing at about $30/min. A ballpark
estimate for producing a two-hour DVD movie is about $20,000. A simple
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. These 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
July 1998, DVDs cost about $2000 to master and about $1.70 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.
Pre-mastering costs are mostly for authoring systems and encoding systems
which cost tens of thousands of dollars, but these too will get much
cheaper in the next few years.
Double-sided or dual-layer discs cost only a little 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 not yet commercially available. (See
3.3.1.)
[5.2] What DVD-ROM formatting tools are available?
* 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.
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.
[5.3] What video and audio encoding tools are available?
Video encoding tools
* Astarte
o M.Pack. MPEG-2 video encoding software for Mac OS. (PixelTools
encoding engine.) $400.
* AuthoringWare
o DVD WISE. Low-end DVD-Video authoring software for Windows.
$1,000.
* Canopus
o 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
o Cinemacraft. MPEG-2 real-time NTSC video encoding software for
Windows NT.
* Darim
o MPEGator 2. MPEG-2 real-time encoding hardware for Windows and
Windows NT. $1,800.
* Digital Ventures
o DVDComposer. MPEG-2 video encoding system for SGI. VBR and CBR.
(C-Cube chip). $50,000.
* Digital Vision
o BitPack. MPEG-2 video encoding workstation. Extendable to HDTV.
o DVNR system for video pre-processing.
* Digigami
o 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)
o MPEGRich. Professional MPEG-2 real-time encoding hardware. CBR
and VBR. Windows NT.
* DV Studio
o Apollo Expert. MPEG-2 video encoding (and decoding) hardware for
Windows NT. $2,000.
* FAST Multimedia
o 601 [six-o-one]. MPEG-2 non-linear editing system with "print to
DVD" option to output MPEG-2 ES or PS.
* Heuris
o 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.
o Cyclone. MPEG-1 and MPEG-2 encoding software designed for OEMs.
Mac OS and Windows NT.
* Ligos
o LSX-MPEG Encoder. MPEG-2 video encoding software. CBR and VBR.
Windows. $150.
* Microcosmos/Nanocosmos
o MPEG SoftEngine. MPEG-2 video encoding software for Windows,
Solaris, and Linux. $250 to $3500.
* Minerva
o Compressionist 110, 200, and 250. Professional MPEG-2 real-time
encoding hardware. CBR and VBR. Mac OS host computer. $70,000.
[No longer available.]
o Publisher 300. Professional MPEG-2 video and MPEG Layer 2 audio
real-time encoding hardware. CBR and VBR. Mac OS. [No longer
available.]
* Optibase
o 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
o DVS3110. Professional MPEG-2 video encoder for PAL and NTSC. CBR
and VBR.
* PixelTools
o Expert-DVD. MPEG-2 video encoding software. CBR and VBR. Windows.
$2,000.
o Simple-DVD. AVI-to-DVD conversion utility for Windows. $1,5000.
* Sonic Solutions
o Sonic DVD Studio. Professional MPEG-2 video encoding hardware.
CBR and VBR. Segment-based reencoding. Mac OS.
o 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
o DVA-V1100. High-end MPEG-2 video encoding hardware. CBR and VBR.
Windows NT.
* Spruce Technologies
o MPEGXpress 3000. Professional MPEG-2 real-time encoding hardware.
CBR and VBR. Windows NT.
o MPEGXpress 2000 (formerly from CagEnt). Professional MPEG-2
real-time encoding hardware. CBR and VBR. Windows NT.
* Tele-Cine
o Film to video (telecine) transfer services.
* VisionTech
o MVCast. Low-end real-time MPEG-2 video/audio encoding hardware
for Windows NT and Solaris. AVI-to-MPEG-2 conversion. $2000.
* Vitech
o MPEG Toolbox-2. AVI to MPEG-2 VBR/CBR. MPEG-2 video editing.
Windows 95/98/NT. $250.
* Wired
o MediaPress. MPEG-2 encoding hardware (PCI). CBR and VBR. Mac OS
and Windows 95/98/NT. $2,500.
* Zapex
o 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.
o 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.
Audio encoding tools
* Astarte
o A.Pack. Multichannel Dolby Digital audio encoding software for
Mac OS. $800.
* Digital Vision
o BitPack. Multichannel audio encoding workstation for Dolby
Digital, MPEG-2, and PCM.
* Dolby
o DP569. Multichannel Dolby Digital audio encoding hardware.
* Microcosmos
o MPEG SoftEngine/Audio. MPEG audio encoding software for
Windows/Solaris. $95/$350.
* Minerva
o Audio Compressionist. Professional Dolby Digital real-time,
5.1-channel encoder. Windows NT.
* Philips
o DVD3310. Professional MPEG-2 multichannel audio encoder.
* PixelTools
o Expert-Audio. MPEG Layer 2 audio encoding software. Windows.
* Sonic Solutions
o Sonic DVD Studio. Professional real-time Dolby Digital 5.1,
MPEG-2, and PCM audio encoding hardware. Mac OS.
* Sonic Foundry
o Soft Encode. Dolby Digital 2-channel or 5.1-channel audio
encoding software. Windows 95/98/NT. $500 and $900.
* Sony
o DVA-A1100. High-end, real-time Dolby Digital 5.1, MPEG-2, and PCM
audio encoding hardware. Windows NT.
* Spruce Technologies
o ACXpress 2000 (formerly from CagEnt). Professional Dolby Digital
real-time, 2-channel encoder. Windows NT.
o ACXpress 5100 (formerly from CagEnt). Professional Dolby Digital
real-time, 5.1-channel encoder. Windows NT.
* Zapex
o ZP-100. Real-time PCI encoder for 2- or 5.1-channel Dolby Digital
and MPEG Layer 2. Windows NT.
Other production tools
* Computer Prompting & Captioning Co.
o CPC-DVD. Closed Caption production system. DOS. $6,000.
[5.4] What DVD-Video authoring systems are available?
* Astarte
o 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.
o DVDelight. Simple, drag-and-drop DVD-Video authoring for Mac OS.
$1,000.
o DVDExport. Software to convert Macromedia Director presentations
to DVD-Video format. Mac OS. $900.
* Authoringware
o DVD Quickbuilder.
* Avid
o Xpress DV. Turnkey workstation based on IBM Intellistation
hardware running Avid Xpress software and Sonic Solutions DVDit.
$9,000.
* Blossom Technologies
o 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
o Amber for DVD. Amber MPEG-2 encoding hardware with Spruce
DVDVirtuoso authoring software. $3,300.
* Compact Data
o SimpleDVD. AVI-to-DVD converter for Windows. $1,500.
* Daikin (Daikin US Comtec Laboratories)
o Scenarist SGI. DVD-Video authoring for SGI. The original.
$35,000.
o Scenarist NT. DVD-Video authoring on Windows NT. Comes in three
versions: Basic, $9,000; Advanced, $19,000; Professional,
$29,000.
o DVDwiz. Low-end authoring for NT.
* DreamCom (formerly Gunzameory)
o DVDRich. DVD-Video authoring/encoding on Windows NT. Uses
MPEGRich encoder and Daikin Scenarist or Intec DVDAuthorQuick.
$30,000.
* DV Studio
o Apollo Expert Author. DVD-Video authoring software for Windows
NT, using Intec DVDAuthorQuick authoring software and DV Studio
Apollo Expert MPEG-2 encoding hardware. $4,000.
o Apollo Expert Archiver. MPEG-2 encoding system for archiving
video to DVD-RAM. $2,500 (DVD-RAM drive included).
* Futuretel
o Crescendo.
* Innovacom
o DVDImpact. DVD-Video authoring aimed at multimedia studios and
corporations. Uses Daikin Scenarist NT or Intec DVDAuthorQuick
software. $29,000.
* Intec America
o DVDAuthorQuick Pro. DVD-Video authoring software for Windows NT.
$8,000.
o DVDAuthorQuick Desktop. Entry-level DVD-Video authoring software
for Windows NT. Appropriate for simple corporate DVD and personal
DVD projects. $2,5000.
* Matrox
o 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
o DVD AuthorSuite. DVD-Video authoring/encoding for Windows NT.
Uses Intec DVDAuthorQuick software, Zapex encoders, and Sigma
Designs decoder. $25,000.
* Minerva
o DVD-Professional SL and DVD-Professional XL. DVD-Video
authoring/encoding systems for Windows NT. Includes Publisher 300
and Minerva Studio. $100,000.
o Impression. DVD-Video authoring/encoding system for Windows.
$10,000.
* MTC (Multimedia Technology Center)
o StreamWeaver Express and StreamWeaver Pro. DVD-Video authoring,
and $900 premastering on Windows. $900 and $3,000.
o DVMotion Express and DVMotion Pro. Authoring systems for Windows,
oriented toward multimedia DVD-ROM production. $1,500 and $5,000.
* NEC
o DV Editor. IEEE-1394 card and and software, plus Sonic's DVDit
LE. Windows 98. Available in Japan only.
* Optibase
o 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
o LQ-VD2000S. Turnkey DVD-Video authoring system, including Windows
NT 4.0 workstation. Uses Panasonic MPEG-2 encoder and LQ-VD3000
emulator. $120,000.
o LQ-VDS120. Additional workstation software for networking with
LQ-VD2000S. $22,550
o LQ-VD3000. DVD Emulator. $15,000
* Pinnacle
o DVD1000. MPEG-2 video editing and DVD-Video authoring system for
Windows. Pinnacle DVD1000 hardware with Adobe Premiere and
Minerva Impression. $8,000.
* Philips
o DVD-Video Disc Designer and DVD-Video Authoring Toolset. Windows
NT.
* Pioneer
o 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
o EasyDVD.
* Sonic Solutions
o 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.
o DVD Creator 2. Mac OS. $12,000.
o 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.
o DVDit for Premiere. Adobe Premiere plug-in for DVD-Video output.
Windows. $400.
* Sony
o DVA-1100. High-end authoring/encoding system with one to eight
stations. Price range starts at $175,000.
* Spruce Technologies
o 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.
o DVDVirtuoso. Low-end authoring/encoding system for Windows NT.
Only available bundled with other products.
o DVDStationCX. Turnkey system using DVDConductor. $25,000.
o DVDStationNLE. Turnkey system using DVDConductor and Heuris MPEG
Power Professional encoding software. $10,000.
* Visible Light
o 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
o DVD Toolbox. AVI to DVD-Video. Write to CD-R, DVD-R, DVD-RAM,
etc. Windows 95/98/NT. $400.
[5.5] Who can produce a DVD for me?
[A] = authoring (including encoding, DVD-R copies, and premastering).
[R] = replication (mastering and check discs).
* [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.
* [R] Americ Disc (Salida, CA, 888-545-7350; Miami, FL, 800-364-0759;
Drummondville, Quebec, Canada, 800 263-0419).
* [A] Atelier Digital (Birmingham, AL), 205-263-7678.
* [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), 415-509-6129.
* [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.
* [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.
* [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 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 Mastering (Sydney, Australia).
* [R] Digital Video Technology 3000 (DVT) (El Segundo, CA).
* [R] Disc Manufacturing Inc. (now part of Cinram).
* [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] 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] GTN (Oak Park, MI), 248-548-2500.
* [A] Hecker & Schneider GmbH (Dortmund, Germany).
* [A] Henninger Interactive Media (Arlington, VA), 703-243-3444.
* [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 Mⁿnchen (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] 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] 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] 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 (Gⁿtersloh, Germany, +49-5241-80 5200; Weaverville, NC,
USA, 828-658-2000)
* [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] StΘ 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] 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] 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's professional services directory.
[5.6] What testing/verification services and tools are available?
* 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, $1,500. 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.
[5.7] Can I put DVD-Video content on a CD-R or CD-RW?
[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 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 playback fails, at
which point the players are no longer looking for DVD-Video content
2) it's much simpler 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.
An alternative is to put Video CD content on CD-R or CD-RW media for
playback in a DVD player. Settop players that are Video CD capable and can
read recordable media will be able to play such discs (see 2.4.5). The
limitations of Video CD 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 Video CD discs. See 5.8 for more on creating Video CDs.
[5.8] How do I copy my home videos/movies/slides to DVD?
If you're rich enough, put together a system with the following components
* a video digitizer ($300-$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)
* 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 ($40)
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. 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, MPEG Maker-2 from VITEC, NTI CD-Maker from NTI, or WinOnCD from
Cequadrat). Quality won't be as good, and playing time won't be quite 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).
[5.9] How do I get a job making DVDs?
Read this FAQ through a few times. For extra credit, read my book, DVD
Demystified, and visit some of the DVD information sources list in section
6.4. Then attend a conference such as DVD Pro, DVD Summit (Europe) or DVD
Production to learn more and to make contacts in the DVD industry. Consider
joining the DVDA. If you can, volunteer to be an intern at a DVD production
house (see section 5.4).
Once you have a little experience, you'll be in great demand! Register at
DVDJobsUSA.com.
------------------------------------------------------------------------
[6] Miscellaneous
[6.1] Who invented DVD and who owns it? Whom to contact for specifications
and licensing?
DVD is the work of many companies and many people. There were originally
two next-generation standards for DVD. The MMCD format was backed by Sony,
Philips, and others. The competing 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 Consortium was replaced by the DVD Forum, which is open to all
companies (more info at <http://www.dvdforum.com>). See section 6.2 or
visit Robert's DVD Info page <http://www.unik.no/~robert/hifi/dvd/> for
links to Web sites of companies working with DVD.
The official DVD specification books are available from Toshiba after
signing a nondisclosure agreement and paying a $5,000 fee. One book is
included in the initial fee; additional books are $500 each. Contact
Licensing Operations Group, Toshiba Corporation +81-3-3457-2643, fax
+81-3-5444-9430. 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 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.
Implementation of DVD products and use of the DVD logo for non-promotional
purposes requires additional $10,000 format and logo licenses. Contact
Toshiba DVD Business Promotion and Support: +81-3-5444-9580, fax
+81-3-5444-9430.
The specification for the UDF file system used by DVD is available from
www.osta.org.
Any company making DVD products must license the patented technology from a
Philips/Pioneer/Sony pool, a Hitachi/Matsushita/Mitsubishi/Time
Warner/Toshiba/Victor pool, and from Thomson. Total royalties are about 6%
(minimum $6) for a DVD-Video player, 6% (minimum $6) for a DVD-ROM drive,
5% (minimum $2) for a DVD decoder, and 10 cents for a DVD disc.
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. 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 free of charge to
hardware makers, but charges a per-copy royalty to content publishers (2 to
4 cents 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.
Dolby licenses Dolby Digital decoders for $0.26 per channel.
[6.2] Who is making or supporting DVD products?
Consumer electronics:
* Aiwa: DVD-Audio and DVD-Video players
* Akai: DVD-Video players
* Alpine: DVD car navigation/entertainment
* Altec Lansing: DVD audio technology
* Ariston: DVD-Video players
* Audiovox: Car DVD players
* BUSH: DVD-Video players
* California Audio Labs: DVD-Video players
* Casio: DVD-Video playres
* 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
* Harman Kardon: DVD-Video players
* Hitachi: DVD-Video players
* Hyundai: DVD-Video players
* Innovacom: PC/TV with DVD support
* 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
* Mossimo: DVD-Video players (China)
* NAD: DVD-Video players
* Nakamichi: DVD-Video players
* NEC: DVD-RAM video camera
* Noriko: DVD-Video players
* Onkyo: DVD-Video players
* Oritron: 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)
* Rotel: DVD-video players
* Runco: DVD-video players and changers
* 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
* Toshiba: DVD-Video and DVD-Audio players and changers
* Unity Motion: DVD-Video players
* Victor (JVC): DVD-Video players
* 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
Studios, video publishers, and distributors:
* A2O Entertainment (wholesale distributor)
* A.D. Vision (anime)
* 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)
* 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
* 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)
* 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 Video Distribution (distributor, UK)
* Disney (Buena Vista Home Video, Dimension Films, Hollywood Pictures,
Miramax, Touchstone)
* DreamWorks SKG
* DVD International (distributor)
* Eaton Entertainment
* Elite Entertainment
* Fantoma
* Essex Entertainment
* 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)
* Ice Storm Entertainment (distributor, Germany)
* Image Entertainment (distributor)
* Impressive (adult)
* IndieDVD (publisher; alliance of independent filmmakers)
* Ingram (distributor)
* King's Road (distributed by Trimark)
* Kino International
* Laserdisc Entertainment (adult)
* Leo Films
* Living Arts (health)
* LucasFilm (distributed by Twentieth Century Fox or Paramount)
* Lumivision (distributed by SlingShot)
* 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)
* N2K Music
* Navarre (distributor)
* New Vision
* New Line (Warner)
* New Horizons Home Video
* NuTech Digital (adult)
* October Films (Universal)
* 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)
* Paramount Home Video (owned by Viacom)
* Parasol
* Passport
* Phantom
* Picture This
* Pioneer Entertainment (distributor)
* Playboy Home Video
* PM Entertainment
* Polygram (Philips partner)
* Pony Canyon (Japan)
* PPI
* Private Media Group (adult)
* Pro7 Home Entertainment (Germany)
* Program Power
* Real Entertainment
* Republic Pictures (defunct, distributed by Artisan)
* Rhino Home Video
* Roadshow Entertainment (Australia)
* Roan Group
* Rykodisc
* Samsung Entertainment Group
* Shanachie
* 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)
* Sterling Home Entertainment
* 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)
* Valley Media (distributor)
* VCA Interactive (VCA Pictures, VCA Labs; adult)
* VCI Home Video
* Ventura
* Victor Entertainment (JVC)
* Victory
* Video Watchdog
* Vidmark
* Vivid Video (adult)
* Walt Disney Pictures
* Warner Bros. Records/Warner Music (Toshiba partner)
* Warner Home Video (Toshiba partner)
* Waterbearer Films
* WIT Entertainment (distributor)
* Wolfe
* World Video
* Xenon
* York
DVD File maintains a list of studio addresses, as well as DVD producer and
distributor information.
Hardware and computer components:
* Acer Laboratories: DVD decoder/controller chips
* Apex: DVD-Video player
* 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)
* ATI Technologies: display adapters with hardware acceleration for DVD
playback
* Avid Electronics: DVD decoder/controller chips
* Axis Communications: DVD-ROM 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 jukebox
* 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
* DVDO: video deinterlacing chips
* DynaTek: DVD upgrade kit
* E4 (Elecede): DVD playback hardware
* Elektroson: DVD-recordable software (top.GEAR)
* 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
* 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
* JVC: DVD-ROM drives, DVD-RAM jukebox
* Kasan: decoder hardware
* KOM: DVD-RAM changer
* 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
* 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
Computer software titles on DVD-ROM:
* 2 Way Media: Launch
* Access Software: Overseer, Tex Murphy
* Acclaim Entertainment: Reah
* Accolade: Jack Nicklaus 4, Family Spectacular
* Activision (Quicksilver): Muppet Treasure Island, Spycraft: The Great
Game, Zork: The Grand Inquisitor
* Aftermath Media: Tender Loving Care
* ALLDATA: automotive information databases
* 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
* Discovery Channel: Leopard Son/Animal Planet, Connections
* Dorling Kindersley
* Electronic Arts: Wing Commander IV
* genX Software: Dead Moon Junction
* Graphix Zone
* Grolier: Multimedia Encyclopedia
* GT Entertainment: Forrest Gump, Reah
* IBM Interactive Media: The Pistol: The Birth of a Legend
* Interactual Technologies: Star Trek VideoSaver
* Interplay
* 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: DΘcouvertes (Junior Discovery)
* Magnum Design
* Mechadeus: The Daedalus Encounter
* MediaGalleries: Multimedia Bach
* MediaOne: VersaDisc
* Microsoft: Encarta, MSDN/TechNet
* Mill Reef: Earthlight
* Mindscape
* Mitchell Repair Information Company: ON-DEMAND
* Monolith: Claw
* Montparnasse Multimedia: Microcomsos
* 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
* Pro CD: Select Phone
* Project Two Interactive: Reah (distributed by GT in U.S., Acclaim in
UK and Ireland)
* Psygnosis
* 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)
* Tsunami: Crazy 8's, Silent Steel, Silent Steel II
* Warner Advanced Media
* Westwood Studios: Command & Conquer
* Xiphias: Encyclopedia Electronica
* Zombie VR Studios: Liberty
[6.3] Where can I buy (or rent) DVDs and players?
* 800.com
* A&B Sound (Canada)
* AccessDVD.com
* Ace VCD DVD (Hong Kong/anime)
* All DVD Movies
* Amazon.com
* AnimeNation
* Anime Depot
* Asian Xpress (Hong Kong films)
* Best Buy
* Best Buy Movie (Germany)
* Beyond Music
* BigStar
* Blockbuster (rental and sales)
* Brainplay.com
* Buy.com
* C&L Internet Club (Canada)
* CDNOW
* Checkout.com
* Digibuster Media (online rental)
* Digital Entertainment (Indian films)
* Digital Eyes
* Direct Video
* DVDCity
* DV Depot
* DVD Domain
* DVD Empire
* DVD EXPRESS
* DVD North (Canada)
* DVDONE
* DVD Overnight (online rental)
* DVDPlus (Europe)
* DVDstreet (region 2)
* DVD Wave
* DVD Zone 2 (region 2)
* Elvic (Netherlands)
* Evolution Audio & Video
* Just Watch It (regions 1 and 2)
* Laserdisc DVD Outlet
* Laser's Edge
* Hifi.com (players)
* Hollywood Video (rental)
* Ken Crane's
* Media Play
* MegaDVD
* Musicland
* NetFlix (online rental)
* On Cue
* OneCall (players)
* OZDVD Warehouse (region 4)
* Reel.com
* Rent A DVD (online rental, Switzerland)
* Ro-Disc (Netherlands, regions 1 and 2)
* Sam Goody
* Second Chance DVD (used)
* Shopping.com
* Shopping Matrix (South Africa, region 2)
* Swinging Planet (UK, Cult TV; region 2)
* Trans World Entertainment (TWEC)
* 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.
[6.4] Where can I get more information about DVD?
Here are a few of the top DVD info sites.
* Robert's DVD Info: <http://www.unik.no/~robert/hifi/dvd/> (tons of
links to news articles and other pages)
* UK DVD FAQ: <http://movieuk.com/dvdfaq.htm>
* Ask Digital Man DVD tech support: <www.askdigitalman.com>
* Home Theater Forum: <http://www.hometheaterforum.com>
* DVD Infomatrix: <http://www.inmatrix.com> (a wealth of information
about DVD PCs)
* DVD Utils: <http://www.dvdutils.com> (PC utilities, software player
reviews, region-free info, more)
* Michael D's Guide to Region 4 DVDs (review and other info on region 4
discs)
* Kilroy's DVD FAQs:
<http://www.CD-info.com/CDIC/Technology/DVD/dvd-faq.html> (technical)
and <http://www.icdia.org/dvdfaq02.html> (oriented toward CD-i) (both
are a little out of date)
* Chad Fogg's technical notes: <http://www.mpeg.org/~tristan/MPEG/DVD/>
* DVD-Video Production Guidebook:
<http://www.nbdig.com/html/dvdmain.htm> (very technical and poorly
translated from Japanese)
* Quantel Digital Fact Book (digital video info and glossary):
<http://www.quantel.com/dfb>
* DVD for not-so-Dummies, from Nimbus <http://www.nimbuscd.com/dvd.htm>
* DVD Primer, from Sonic Solutions
<http://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 <http://dvddemystified.com>.
------------------------------------------------------------------------
[7] Leftovers
[7.1] Unanswered questions
(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.?)
[7.2] Notation and units
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 "kilo," "mega," and "giga" generally 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, and "gigabytes" for 1,073,741,824 bytes.
In 1999, the IEC produced new prefixes for binary multiples: kibibytes
(KiB), mebibytes (MiB), gibibytes (GiB), and so on. 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.
[7.3] Acknowledgments
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.
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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]