Mr. Gary Reber, Editor-In-Chief and Publisher of Widescreen Review magazine, in his presentation on "The Future Of Prerecorded HD Formats," will cover the origins and technical elements of the JVC D-VHS® D-Theater™ platform, the JVC-developed D-Theater copy protection encryption scheme, studio support, and the availability of D-Theater titles. Mr. Reber will also cover the development of competing HD-DVD optical disk technologies and the challenges ahead, related to copy protection encryption schemes and protected A/V interfaces necessary for prerecorded high-value, high profile content production.

Introduction

The first working device for producing electrical signals for television transmission was a mechanical scanning system built by Paul Nipko in 1884. Later Valdimer Zworykin immigrated to the United States from Russia to develop an all-electronic television system. It was only after a technical paper given by Zworykin in 1929 that another Russian immigrant and then Vice President of the Radio Corporation of America (RCA), David Sarnoff, was inspired enough to create a business. Sarnoff provided Zworykin with the laboratory resources to realize the dream and then in 1939 announced to the world at the New York World’s Fair that the beginning of a new era—an era where moving images and sound would be in every home—was at hand.

Sarnoff controlled both the manufacturing of television sets through RCA and the transmission signals via the National Broadcast Corporation (NBC). Sarnoff clearly understood that only with a combination in the marketplace of consumer TV sets and TV signals could the industry be born. This scenario of hardware supported with software has been the basis of numerous successes in consumer electronics. The most successful launch was the DVD platform.

In 1996, fifty-seven years after the New York World’s Fair, the Victor Company of Japan introduced a high-definition VCR platform that set the highest standard for consumer use recording and playback. The D-VHS® format was introduced a year before the DVD-Video format was launched. Kazuno Kohda is credited with the invention of Digital or Data-VHS.

The D-VHS format sets the highest standard thus far for HD picture quality, and as well, sound quality in a home video format. But HD-DVD is clearly on the horizon and will inevitably become the preference of consumers for prerecorded high-definition content. I will address the possible forms that HD-DVD will take and whether HD-DVD will equal or exceed the performance standard set by D-VHS.

In 1992, I founded Widescreen Review as a home theatre enthusiast magazine with the intent to educate and serve as a technical resource that explored "the best that it can be" in a home theatre movie experience. Widescreen Review is a magazine with no vested interest in any technology, nor egotistical interest in a particular product technology. Yet Widescreen Review has been criticized by some people, and others in the media, who think that we have posed D-VHS as a competitor to HD-DVD, or even the existing DVD format. This is absolutely not true. As an enthusiast publication, we are only interested in "the best that it can be," regardless of technology or manufacturer, or price, and appreciate any accomplishment that improves the picture and sound experience.

Experience has taught me that by supporting "the best that it can be" in the magazine, the bar for excellence raises across the board, and often results in better performance in products that are far less expensive down the road.

We brought the D-VHS HD platform to the attention of our enthusiast readers with our recent filled-to-capacity weekend D-Theater Movie Festivals™. We premiered to enthusiast and leading industry figures the extraordinary dimensionality and resolution that the D-VHS D-Theater™ platform delivers as an "HD-plus" home theatre experience, far exceeding the performance capabilities of the very best DVDs, and even ATSC-standard (American Television Standards Committee) HDTV over-the-air and satellite-delivered broadcasts.

On November 28, 2002, I delivered a presentation on D-VHS D-Theater to the International Digital Cinematography Conference on Production and Distribution held in Moscow. In that presentation, I covered the origins of the D-VHS format, the technical elements that constitute the format, the JVC-developed D-Theater copy protection encryption scheme, studio support, and the availability of D-Theater titles. For the benefit of this audience, I will cover those topics, as well as the development of various HD-DVD technologies competing to become the single-format optical disk standard.

D-VHS was developed in order to meet the recording requirements of digital broadcasts while ensuring that the existing VHS video images that have accumulated thus far will remain accessible and will not become obsolete.

In the 21st century, not only will TV broadcasts and cinema exhibition go digital, but also a wide variety of information will be transmitted as digital signals (bit stream data), and a household appliance that can record and store information will become necessary.
While tape media has served as an excellent delivery medium, since the advent of optical data storage, commercially successful in the form of Compact Discs (CDs) for audio and software distribution and Digital Versatile Discs (DVDs) for video distribution, tape has become less desirable as the preferred consumer storage medium. Companies involved in future optical data technologies are focused on the next generation of optical data storage, which promises HD digital home theatre recording and HDTV distribution. In terms of specific optical disk technologies, however, there are distinguishing differences, which determine the volume of data to be recorded, and thus, impact the quality of video and audio.

What follows is a description of several technical aspects associated with D-VHS and optical disk technologies.

Table I displays a comparison of D-VHS and optical disk technologies in terms of several parameters. Three next-generation optical disk technologies are listed. They are the HD-DVD-9 (a Warner Bros. technology now being developed in the DVD Forum, the standards body for the DVD platform), the Advanced Optical Disk (developed by Toshiba and NEC), and the Blu-ray Disk (now called BD, as developed by a consortium of nine consumer electronics companies—Hitachi, LG, Matsushita, Pioneer, Philips, Samsung, Sharp, Sony, and Thomson), which exhibits parameters similar to the abandoned Digital Video Recorder (DVR). All three next-generation optical disk technologies have the potential to become commercially successful in terms of distributing HDTV. The Advanced Optical Disk and Blu-ray Disk also have the potential for recording HDTV.

D-VHS

Among the various types of storage media, D-VHS tape media has the advantage of removable high-storage capacity (50 GB). Even next-generation optical disks can only store 15 to 27 GB (gigabytes) of data on a single side, which is only about half that of D-VHS.

As previously stated, the D-VHS format was launched by JVC, the developer of VHS, in 1996. The format features full HD record and playback capability, and can decode D-VHS video recorded in the 18 ATSC digital video formats. D-VHS shares the same form factor tapes as standard VHS. The format is backward record and playback compatible with Super-VHS and VHS.

D-VHS delivers an incredible 28.2 megabits per second (Mbps) bit rate. This is a substantially higher data rate than the 19.3 Mbps ATSC HDTV standard bit rate for over-the-air broadcast HDTV in the United States, and far exceeds the 4.5 Mbps DVD-Video average data transfer rate for a two-hour movie. As with the ATSC and DVD-Video systems, the format uses MPEG-2 compression. Because of D-VHS’s 28.2 data rate, HD ASTC broadcasts can be recorded with no additional compression, thus capturing 100 percent of the broadcast signal quality.

D-VHS’s information density is 1920 x 1080 versus DVD-Video standard-definition (SD) 720 x 480. The format supports up to 50 GB of storage capacity. Such capacity supports up to four (4) hours of HD recording at 28.2 Mbps and 16 hours of SD (DVD-Video quality) recording at 6 Mbps, or eight (8) hours at 14.1 Mbps.

The D-VHS format adopts IEEE 1394 as the digital input/output interface (also referred to as FireWire® or iLink®) incorporating DTCP or Digital Transmission Content Protection (also known as 5-C) copy protection technology.

JVC’s first generation D-VHS D-Theater VCR, the HM-DH30000U, will output MPEG digital video from its IEEE 1394 interface (four-pin terminal), but only when that video is not copy-protected. Digital video from DVDs that are not copy protected can be recorded via the DVD analog video and audio outputs using the HM-DH30000U on-board A/D converter and MPEG encoder, but most DVDs are copy-protected.

The JVC HM-DH30000U features, in addition to IEEE 1394, an analog HDTV video output compatible with the YPbPr input included on most high-definition displays and will output YPbPr analog component video signals in the 1080i (interlaced), 720p (progressive), 480p, or 480i formats. The format and the JVC VCR are also capable of outputting 1080p. The platform’s supporting studios and JVC are working on the 1080p-mastering interface. It is the intent of the studios and JVC to eventually release D-Theater-encrypted movies in 1080p.

The D-VHS D-Theater platform is Dolby® Digital 5.1-capable in playback of prerecorded D-VHS and D-Theater content up to the full 640 kilobits per second (kbps) data rate. When recording through the IEEE 1394 interface, the data rate of the source Dolby Digital bit stream will be recorded.

With respect to DTS®, there is a caveat—JVC is completing work on their DTS Digital Surround™ encoder so that future D-Theater titles can be encoded in the full data-rate DTS bit stream. The supporting studios intend to release D-Theater titles with a DTS bit stream.

At the 2003 International Consumer Electronics Show (CES) held in early January in Las Vegas, Nevada, JVC showed a prototype HM-DH40000U D-VHS D-Theater HD VCR, which will likely be introduced in the fourth quarter of 2003, perhaps at the Custom Electronic Design & Installation Association (CEDIA) Expo in September. This unit should incorporate DTS, but no specific information was provided by JVC to confirm such or to provide information on other features, including A/V interfaces.

At the CES, Marantz showed a D-VHS D-Theater HD VCR, Model MV8300, which is scheduled for release in March 2003. This VCR is based on the JVC HM-DH3000U’s features and does not incorporate DTS.

In order to secure the support of Hollywood studios to release their movies on the format, JVC developed D-Theater-encrypted copy protection. This extremely robust encryption algorithm was introduced in 2001. Following extensive testing by the studios, the home entertainment divisions of four studios—Artisan Entertainment, DreamWorks Home Entertainment, 20th Century Fox Home Entertainment, and Universal Studios Home Video—joined with JVC to support the new D-VHS D-Theater software platform for high-definition copyrighted prerecorded content. The studios are satisfied that the D-Theater encryption scheme provides a secure level of protection to prevent the unauthorized duplication of their movies and other high-value prerecorded content. The support of these major content providers marks the next phase in the acceptance of high-definition as the new standard for home entertainment and television.

As of February 25, there are 49 prerecorded titles now available—34 studio titles D-Theater encrypted and 24 HDNet D-VHS titles without D-Theater encryption. HDNet is a HD channel carried by the DirecTV satellite network.

All of the D-Theater HD tapes are mastered in the 28.2 Mbps mode, a substantially higher data rate than the ATSC standard 19.3 Mbps for HDTV, so D-Theater movies can deliver even higher quality images than HDTV broadcasts. In fact, some terrestrial and satellite broadcasts do not even use the full ASTC bit rate.

The first day-and-date D-Theater title to be released simultaneously with the DVD-Video and VHS release was 20th Century Fox Home Entertainment’s Ice Age. The release date was November 26. Not only was this the first day-and-date D-Theater title, but Fox’s $180 million smash hit also features the first "Special Edition" on this new HD format, boasting an all-new, exclusively produced five-minute CGI animated short, Scrat’s Missing Adventure.

Continuing their support of new high-definition technology, Artisan Home Entertainment and Universal Studios Home Video have announced plans to roll out nine new titles in the D-VHS D-Theater format in the first two quarters of 2003. During this time we can expect more D-Theater day-and-date titles with DVD.

When the provision for D-Theater was introduced in 2001, JVC made D-Theater a part of D-VHS licensing. Still, there is at present only two D-VHS VCRs marketed in North America with the D-Theater feature—JVC’s HM-DH30000U and Marantz’s MV8300, which was introduced at the 2003 CES. Mitsubishi, which markets another D-VHS VCR in North America, chose not to license D-Theater, even though without the D-Theater feature prerecorded movies released by studios will not play back. The D-Theater feature is licensed for use only in North America at the present time.

The D-Theater feature adds chapter search, audio selection, running audio commentary, alternate foreign languages, and closed-captioning to the standard D-VHS feature set. While these features are impressive for a VCR, other interactive features found on DVD are not possible on the D-VHS D-Theater platform.

Why Support D-VHS?

The compelling reason to support the D-VHS D-Theater platform is the attraction of prerecorded HD movies. The other compelling reasons to support the platform are the capability to record HD, archival of content long-term, and compatibility with legacy VHS software.

Prerecorded movies are available now! I made the decision to support Widescreen Review’s readership, which I knew would embrace this platform, with a shopping service so they could purchase D-VHS and D-Theater titles directly from www.WidescreenReview.com and our subsidiary Web site—www.DVHSMovieGuide.com.

Looking back over the past twelve years of Widescreen Review’s existence, I felt that the D-VHS D-Theater platform was a significant event in the history of imaging science. I have been a proponent of true high-definition video since the inception of the technology and extensively covered the H/DTV debate amongst the technologists, broadcasters, Federal Communication Commission (FCC), and the Consumer Electronics Association (CEA). Thus, I have been deeply involved in the issues surrounding the transition from analog to digital broadcast since founding the magazine. While the issues, with respect to HDTV in the United States, are still unresolved and there is much to write about, I think it is important to appreciate that the D-VHS format sets the highest standard thus far for HD picture quality and is playing an integral role in the transition to HDTV.

As a production tool, the D-VHS format is a cost-effective medium for viewing HD dailies and other work. Blank tapes cost either $15 or $25, depending on storage capacity. Studios like the medium because of its full content security via D-Theater encryption. The presentation quality is equal to that of d-cinema screenings of motion pictures. Picture performance rivals the D-5 digital video studio master, even at 28.2 Mbps versus D-5’s 375 Mbps. We performed extensive A/B comparisons at the Widescreen Review facilities using D-5 clones and D-Theater versions of several Universal Studios titles in our Reference Holosonic™ Spherical Surround™ Home Theatre Laboratory with our state-of-the-art Runco and Sony 9-inch CRT projection systems and Stewart Filmscreen (see Issue 60, May 2002 or WSR’s HDVideo Special Edition, Fall/Winter 2002/2003). The two sources were virtually indistinguishable. We concluded: "D-VHS is D-5, slightly softer!"

It’s more than HDTV.

The D-VHS D-Theater platform isn’t only about HDTV. The platform provides standard-definition digital recording quality that is far superior to anything available from an analog VCR. For those who keep a library of programming from satellite or terrestrial broadcasts, switching to digital tape will greatly improve picture quality.

There simply are no other current alternatives for prerecorded HDTV programming, and I believe competing self-interests, economic issues, and copy protection concerns still put a prerecorded high-definition optical disc introduction two to four years away, or more.

Even though D-VHS D-Theater is a step back in operating convenience, it is a giant leap forward in accessible video quality and the ability to choose what and when we watch HDTV.

HD Optical Disks

I am hopeful that an ultimate optical-based HD format will be required to equal or surpass D-VHS performance, in order for it to be embraced by enthusiasts. Two of the three main contenders for the HD optical disk throne, both blue-laser-based, show promise to meet, if not exceed the performance of D-VHS. Each has its own combination of formats and codecs. All three variations of HD-DVD will require new players to read the discs. The DVD Forum, the standard-setting body for the DVD platform, is developing the 0.6-mm bonded disk proposed by Toshiba and NEC as the basis of its next-generation DVD standard utilizing a blue laser. This next-generation HD-DVD, called Advanced Optical Disk, represents a minimal extension of the current DVD format with smaller pits and tracks but no change to the data layer depth. Although a blue laser is needed to read the disc, video can be encoded with MPEG-2 or a new codec still to be chosen. While Toshiba and NEC jointly proposed the Advanced Optical Disk System to the DVD Forum in August 2002, the Blu-ray Disk or BD proponents, supporting a competing blue-laser technology, have decided to launch their format without the sanction of the DVD Forum, even though the nine companies supporting the format are also members of the DVD Forum. The third contender is the Warner Bros. proposal for an HD-DVD-9 disc, an adaptation of the existing dual-layer DVD-9 format, requiring no changes to the physical disc, only a new codec for the video.

In optical disk systems, disk capacity is maximized through the use of high numerical aperture or NA and short laser wavelength. To insure maximum contamination protection, the disk’s protective layer should be as thick as possible. However, the combination of thick protective layer and high NA is not easily accomplished. High NA systems are sensitive to changes in substrate thickness and disk tilt. Manufacturing variations create thickness non-uniformities, which are usually a small percentage of the total disk thickness. Motor instabilities induce tilt as the disk spins. These and other factors cause aberrations and degrade the read-out signal. In order to limit these effects, the disk substrate is made as thin as possible without sacrificing contamination protection.

The most conservative optical disk technology is the Video CD with a thick protective layer, relatively low NA, and long laser wavelength. This produces a system with an ideal spot size of 1.6 micrometers that is not very sensitive to environmental factors like dust and scratches. DVD technology uses a shorter wavelength laser, higher NA optics, and a thinner protective layer. The combination of short wavelength and higher NA produces a spot size of about 1.1 micrometers. The protective layer is thinner and thus, DVDs are slightly more sensitive to dust and scratches than CDs. While the higher NA reduces the focal depth, DVDs have more robust error management. The Warner HD-DVD-9 system is exactly the same as a DVD in terms of the optical parameters. The Advanced Optical Disk and Blu-ray Disk systems both use a new blue laser source that emits 0.405-micrometer light. The Advanced Optical Disk system uses the same protective layer thickness as a DVD, and it uses the same NA objective lens. Due to the short wavelength, the spot size for the Advanced Optical Disk is about 0.62 micrometers. Sensitivity to dust and scratches is about the same as a DVD. Sensitivities to thickness variations and disk tilt are worse, however, due to the wavelength difference. In order to increase the capacity of the Advanced Optical Disk to 20 GB, margins like tilt sensitivity need to be significantly improved in the Advanced Optical Disk and player systems, as compared to DVD players. The Blu-ray system uses both higher NA and a thinner cover layer. The spot size is 0.48 micrometers, which is the smallest spot size of all the technologies listed in Table I. However, because of the high NA, the protective layer had to be made thin to limit sensitivity to thickness variations and disk tilt. Therefore, Blu-ray disks are sensitive to dust and scratches, and thus, in their naked (without protective cartridge) form, are not as consumer-friendly as the other two naked optical disk technologies.

To the user, all generations of optical disks look very similar. They all are round disks that are approximately 120 mm thick. The CD uses a simple 1.2 mm thick substrate. Data is recorded on only one side of the disk, through the clear 1.2 mm substrate, which also serves as the protective layer. DVDs, Warner’s HD-DVD-9s, and Advanced Optical Disks use a format where the layers are separated by a thin adhesive spacer (see Figure 1B). The two layers are fabricated before bonding at the same time as the individual 0.6 mm substrates. Like the CD, data is recorded and read through the clear substrates. It is likely that the Warner HD-DVD-9 and Advanced Optical Disk will also take advantage of this multiple-layer concept. Blu-ray Disks initially will have only one layer on one side. Next-generation BD product will probably be a two-layer single-sided disk. Eventually, the dual-layer dual-sided disk may be produced. Because of the thin protective layer, the Blu-ray Disk will likely be used with a cartridge, as was demonstrated at the 2003 CES. A cartridge-based disk system will be more expensive to produce and cost more as a consumer prerecorded HD delivery medium. If Blu-ray follows the development of DVD-RAM, the product will first be released in a cartridge and then migrate to naked disks that do not need a cartridge. The difference in the Blu-ray Disks that do not need a cartridge is the addition of a thin, hard protective coating. Blu-ray Disks, like DVDs and Advanced Optical Disks utilize true error correction. The error correction scheme in Blu-ray is designed to allow random file manipulation, like DVD. It also includes a more robust correction scheme called "Picket ECC" that partially counters the increased sensitivity of Blu-ray to dust and scratches by emphasizing correction of burst errors.

DVDs allow very efficient methods for data compression. MPEG-2 with variable bit rate allows data to be read out from the disk as it is required, rather than supplying data at a constant rate. Slowly-moving scenes require much less information per frame than fast-moving scenes. Still, it is not practical to store HDTV on DVDs with MPEG-2, as DVDs are not capable of the 13 Mbps random data rate to support MPEG-2. The Advanced Optical Disk exhibits acceptable data rate and reasonable user data capacity for up to two hours of HDTV per side compressed with variable bit-rate MPEG-2. Blu-ray has slightly higher capacity and data rate. The two-hour playtime for HDTV with Blu-ray in Table I is really a specification for real-time recording, which is not easily compressed into an efficient variable-rate scheme. Blu-ray should easily provide two hours or longer of prerecorded HDTV per side compressed with MPEG-2.

Warner HD-DVD-9 disks play in a common DVD player that is equipped with an advanced video operating system implementing MPEG-4, or similar, compression. In this environment, the Warner HD-DVD-9 system may provide up to 135 minutes of HDTV per data layer at an average 7 to 8 Mbps data rate (at 1920 x 1080 resolution with progressive scan output). Research by Warner Bros. has shown that 90 percent of all movies would fit on an HD-DVD-9 disc offering a data rate of 7 Mbps. At 8 Mbps, there would be sufficient space for 80 percent of movies. At 9 Mbps, the figure is still 70 percent of movies and at 10 Mbps, 50 percent of the film titles could fit on a disc.
If MPEG-4 or similar compression technology is successful, it can also be applied to the Advanced Optical Disk and Blu-ray Disk systems. However, at this time, MPEG-4 is meant as a format only for prerecorded video. The computation power required to process a HDTV movie into MPEG-4 is currently beyond the consumer market, thus the need for MPEG-2 in a record able HD-DVD format.

Comparison With D-VHS

Both D-VHS and optical disks have the potential to record and play back at least two hours of HDTV. D-VHS in the HS mode should record or play four hours of HDTV. Both the Advanced Optical Disk and the Blu-ray Disk system can record and play back HDTV video. The Warner HD-DVD-9 is for prerecorded playback only.

A basic distinction between D-VHS and optical data storage is the bit-rate scheme. Tape is a serial, fixed bit-rate scheme at a constant data rate. Although D-VHS has more raw data volume, the random access capability of optical disks allows a variable bit-rate scheme that stores video data more efficiently than the fixed bit-rate scheme of D-VHS. Therefore, fewer gigabytes are required to store the same length and quality of HDTV production on optical disks.

The physical differences between D-VHS and optical disks are also important. D-VHS has no protective layer. There is no working distance between the readout head and the tape surface because magnetic tape recording is a contact technology. Therefore, tape is prone to contamination and breakage. Tape heads wear out. Tape can also shrink. Although scratched, a simple buffing procedure can clean an optical disk. The procedure for cleaning tape heads is not as straightforward. Compared to rugged and reliable optical disk technology, tape is not an effective medium to archive HDTV.

D-VHS requires a cartridge. The only optical disk technology that has demonstrated the use of a cartridge is the Blu-ray Disk system. The Blu-ray cartridge is used for contamination protection. Even so, the working distance of around 0.1 mm and protective layer thickness of 0.1 mm are large compared to the contact recording found in D-VHS players.

The Future

Warner’s HD-DVD-9 requires the least optical system development of the three new optical disk technologies. New decoder chips and system architecture changes are necessary, but no changes are required to the basic DVD optical system. It is likely that, if accepted by the industry, the Warner HD-DVD-9 system would be the first commercial optical disk product specifically designed for HDTV. While Warner’s red-laser HD format could be introduced quickly, it will probably be held until the Advanced Optical Disk blue-laser HD format can be released at the same time. Warner is pushing for red-laser HD-DVD-9, but only as part of a single HD-DVD format. Just as today there are DVD-5s and DVD-9s, and most customers don’t know or care about the difference, there could be red-laser HD and blue-laser HD. Red-laser HD discs would have lower capacity but would be cheaper, just like DVD-5 discs, while blue-laser HD discs would have higher capacity but would cost more to replicate, like DVD-9s. As time goes by, the cost difference will inevitably decrease, but for the first few years of the format there could be a difference in replication cost.

HD-DVD-9 is seen as complementary rather than competitive with blue laser, and both Warner and Toshiba would like the technology to be integrated with blue laser players. Warner’s vision is of SD DVD-Video and HD-DVD content co-existing, so consumers will go into stores and find both SD and HD discs and players. While HD content will not play on SD players, HD players will be able to read existing SD DVD-Video content and HD content because "inside" every blue laser player will be a red laser player.

The Advanced Optical Disk requires some significant changes to the optical system, including the addition of a blue laser and the associated detectors, but the technology for making disks is very similar to existing DVD technology.

Blu-ray could be considered the "true" HD format: it has high capacity and high data rates (up to 36 Mbps), so you can easily get the same HD quality as D-VHS using MPEG-2. The Blu-ray system, however, requires the most changes of the three, including a blue laser, detector, and advanced objective lens. Blu-ray also requires new disk and cartridge manufacturing technology, which may be difficult to implement in a short time-frame. The Blu-ray group is busy working independently from the DVD Forum to get their format done. It’s possible that Blu-ray recorders could be out in time for the December 2003 holiday season, but it’s more likely we won’t see them until 2004, at least in the U.S. Originally the Blu-ray group was ignoring prerecorded movies and concentrating entirely on introducing Blu-ray as a home recording format, but recently they realized that content is what makes or breaks a format. (Without Hollywood movies, DVD would be nowhere.) Work is now underway in the Blu-ray group to define a ROM version and a specification for video navigation to provide menus and interactivity ala DVD-Video. Even so, since Blu-ray requires significant changes across the entire disc replication industry, it will be some time before movies can be distributed on prerecorded Blu-ray discs. How long, you ask? It will take at least one year for Blu-ray to make it out of the laboratory and probably two years to make it into homes. The first version of Blu-ray might be for home recording only, in which case it might take another two or three years until there’s a prerecorded version for movies. So it could take until 2005 to 2007, perhaps longer. Many of us wish we had HD-DVD today but do we want to wait that long?

Content holders are likely to find HD-DVD-9 very attractive in the early years of HD-DVD because both blue laser formats will initially be low-volume and cost two to three times to manufacturer compared to HD-DVD-9 discs. As with SD DVD-9, HD-DVD-9 discs are easier to make and cost under $1.00 to produce.

As always, copy protection is lurking in the background. Copy protection issues delayed the release of DVD by about six months in 1996 and 1997. It could once again cause significant delays in the release of HD-DVD, especially since studios are even more sensitive about releasing "studio master quality" versions of their titles. The copy protection scheme will probably be a variation of CPPM (Copy Protection for Prerecorded Media), the improved version of CSS (Content Scrambling System) that’s used for DVD-Audio discs (known as CSS II). Again, any attempt to release HD-DVD recorders before things such as copy protection and protected A/V interface standards for HD-DVD video are finalized means the recorders won’t be able to play HD movies. We’ve already seen the results of this conundrum in a million or so DVI (Digital Visual Interface) displays that can’t show video protected with the HDCP (High-bandwidth Digital Content Protection) encryption protocol and the next-generation HDMI (High Definition Multimedia Interface) A/V interface and HDCP.

The upshot of all this is that there probably won’t be a "transition" format for HD-DVD. It really isn’t an issue of red-laser HD-DVD "competing" with blue-laser HD-DVD, since it looks like they will be released hand-in-hand as variations of a single HD-DVD format approved by the DVD Forum. But there is definitely a major train wreck shaping up between the Forum’s blue-laser HD-DVD and Blu-ray, which is especially ironic since Blu-ray companies are all members of the DVD Forum. The DVD Forum is expected to reach a decision, at least with respect to HD-DVD-9, during the first half of 2003.

All three optical disk technologies will require double inventory of prerecorded HDTV to coincide with DVD and VHS, and D-VHS D-Theater releases. One promising other optical disk technology which does use a backward-compatible, single-inventory approach is being developed by Pixonics (www.pixonics.com). While I am under a non-disclosure agreement, I can tell you that the concept involves layered encoding for backward compatibility. This approach also is being proposed to the DVD Forum. This has been extensively covered before in Widescreen Review (see Issues 43, November 2000; Issue 35, November/December 1999; and Issue 34, September/October 1999), particularly in interviews with Joe Kane and Jim Taylor, both contributing editors. The basic idea is that instead of jumping to a completely new format that won’t play on existing players, the SD version of video can be encoded along with the "difference signal" created by "subtracting" the HD version from the SD version. The result is a video stream that could play in standard players, while the HD enhancement layer could be read and decoded by HD players and added to the SD base layer to create an HD signal. The nice thing about this approach is that discs could be released today that would play in SD on the existing 250 million DVD playback devices worldwide, but could also provide an HD signal for future players. Some potential disadvantages are that this approach is probably less efficient than a pure HD approach and most attempts to make it work have resulted in degradation of the SD signal. In other words, in order to get really nice HD quality tomorrow, you might have to live with lower SD quality today. How many people are willing to make that sacrifice?

A few of the scenarios that might play out:
- Realistic case: two formats (red + blue versus Blu-ray)
- Worst case: three incompatible formats (red versus blue versus Blu-ray)
- Really worst case: splits within the Blu-ray group resulting in even more competing formats
- Utopian case: a single format (blue or red + blue)

The one thing we can be fairly certain of is that backward compatibility will be preserved. Just as today’s DVD players can play audio CDs, tomorrow’s HD-DVD players will play today’s SD-DVDs (and audio CDs to boot). The players may have to get physically bigger just to make room for all the little logos on the faceplate. Customers will expect future DVD players to be able to play the following:
CD (CD audio)
CD-R (CD audio, MP3)
CD-RW (CD audio, MP3)
DVD (DVD-Video)
DVD-R (DVD-Video)
DVD-RW (DVD-Video)
DVD+R (DVD-Video)
DVD+RW (DVD-Video)
HD-DVD-9 (red laser HD)
Blue laser HD

The player manufacturers have their work cut out for them. The next few years of DVD development should prove most interesting.

Conclusion

In conclusion, as previously forecast in Widescreen Review past issues, an impending format battle is imminent. Even so, already, the D-VHS D-Theater platform is proving to satisfy current and future HD adopters, as is evidenced by the increasingly supportive home theatre Internet forums - www.avsforum.com and www.hometheaterforum.com - the sales of JVC’s HM-DH30000U and Marantz’s MV8300 VCRs and prerecorded D-Theater titles.

I certainly hope that HD-DVD meets or exceeds the specifications of D-VHS and that a single standard, at least equal to the video and audio performance of the D-VHS platform, arrives soon.

Still, I support D-VHS, because right now it is technically the best video format available to the consumer in terms of picture (and sound) quality, and rivals the picture quality of d-cinema.

I think D-VHS can be an integral part of the overall transition to HDTV, since we’re at a point in time now where some real tangible software is needed to demonstrate to a wider audience the capability of HD, as well as to serve the early and current adopters who have already invested in HD-capable displays and are eagerly waiting for true HD-quality source material. Having some really good HD programming from motion pictures is key in this respect.

P.S. Special thanks to Jim Taylor and Tom Milster, both contributors to Widescreen Review, and to Perry Sun, Managing Editor, for their contribution to this presentation.