Because DVD-A supports higher-fidelity, lossless surround, the format is what the record and recording industries have wanted for years.
THE DVD-AUDIO SPEC IS FINALLY IN PLACE. So, where is the flood of titles? While pro's await the impending consumer roll-out, there's still much to learn about what goes into creating DVD-Audio. Hint: It's more than 24/96 multichannel audio.
There's usually a stage in the life of a new consumer electronics product when all the technological elements have been put in place, but the marketing effort has yet to really hit its stride. Sooner or later, the format's proponents either get their message across — and the format takes off — or they fail to make a compelling case, and their wonderful invention never gets traction.
DVD-Audio is in this limbo stage right now. The format's development was as agonizingly slow as any in memory, and the “launch” — if one can call it that — appears to be more of the same. There's little evidence of a concerted effort like the one that kick-started the Compact Disc. The good news is that universal DVD players, which handle both DVD-Audio and DVD-Video, are available in stores, though they still make up a small percentage of the players on display (perhaps because they are priced significantly higher than basic DVD-Video players). But the same major labels that spent years working with electronics manufacturers to define the specification are in a state of suspended animation when it comes to putting out titles.
Aside from the obvious effect of leaving would-be “early adopters” without much to play in their new machines, the reluctance of major labels to take risks with DVD-Audio creates a vicious circle in the production realm. With few titles on the release schedule, there's little incentive for mastering houses or DVD facilities to invest the time and money that it takes to be able to create DVD-Audio masters. And the dearth of DVD-capable mastering houses seems to reinforce the labels' apparent judgment that the format just isn't ready for a big push.
Despite limited incentives, however, some facilities have forged ahead with acquisition of DVD-Audio capabilities. As in the early days of CD, these pioneers have been honing their technique with independent label projects while they wait for the majors to break open a more mainstream market. From their experience, we can learn about the why and how of making a DVD-Audio title.
MORE THAN AUDIO
The first thing to keep in mind about DVD-A is that it's more than simply an audio format. It's actually a multimedia format that supports high-resolution audio and uncompressed PCM surround sound. (For a complete explanation of DVD-Audio's capabilities and organization, see “Music Meets Multimedia: Understanding the DVD-Audio Format” in the December 2000 issue of Mix.)
With DVD-A, your album can be simply a very high-quality Pure Audio title, with 24-bit resolution at sample rates up to 192 kHz for stereo program and 96 kHz for surround (up to six channels). But an album may also include features such as graphics, photos, animation, clickable lyrics and even music videos. And, unlike attempts to combine the features of music CDs and CD-ROM into an “enhanced” CD, DVD-A plays back on a set-top player, so you don't need to sit at a computer to enjoy a title's multimedia components.
DVD-A's multimedia capabilities serve to clarify for consumers — many of whom won't notice the improved audio resolution — the distinction between DVD-A and CD. But the same features actually blur the line between DVD-A and its close relative, DVD-Video. DVD-Video also supports uncompressed surround sound (20-bit/48 kHz for six channels), as well as higher resolution than CD (up to 24-bit/96 kHz for stereo). And its interactive video capabilities are more advanced than those of DVD-A.
Because the two formats share a single name (DVD) but vary in their capabilities, the similarities make confusion inevitable, not only among the general public, but even within the music industry. James Moore, technical director and operations manager at Metropolis DVD in New York City, says clients often “don't understand that DVD-A is very different than the DVD that they know, and that it requires a new player. Most people think that DVD-A is just a DVD with music instead of movies.”
STUDIO EXPERIENCE IN THE HOME
With DVD-Video already well-established, why use a brand-new format with virtually no installed base of players? “The DVD-Audio format has some wonderful features, and I'm sure it will continue to flourish,” says Brian Lee, chief DVD authoring and graphic design engineer at Gateway Mastering and DVD in Portland, Maine. “Its advantages are high-resolution audio streams, browseable stills with music playing, and the opportunity to play the disc without a TV monitor for playback in a car or Walkman.”
“One of the main reasons clients have chosen DVD-Audio over DVD-Video is because of the quality of audio available on the format,” adds Kurt Alexander of DVD-Audio client services at Panasonic Disc Services Corporation in Torrance, Calif. “DVD-Video can play back PCM audio, but due to the capacity limitations after video elements are accounted for, the preferred format in DVD-Video is generally Dolby Digital or DTS. This type of audio, unfortunately, uses a ‘lossy’ type of compression.”
Because DVD-A supports higher-fidelity, lossless surround, Alexander continues, the format is what the record and recording industries have wanted for years. “Clients want to be able to place the listener into the actual recording environment that resembles what the music was intended to sound like in the studio,” he says. “A 6-channel, 96kHz/24-bit recording will convey a new understanding and truer interpretation of what the artist or band originally intended on the recording. Some clients see the current 2-channel, 16-bit/44.1kHz format as an option not worth attempting on future projects.”
Ari Zagnit, DVD developer at Henninger Interactive Media Services in Arlington, Va., agrees with Alexander's assessment. “If you ever talk to an audio engineer,” he says, “the one thing that they all seem to say about their productions is, ‘Man, if they could only hear what I hear.’ DVD-Audio can provide that experience. The primary goal in creating a DVD-Audio disc is to try and re-create the control room experience in the home environment.”
Unfortunately, according to Gateway's Bob Ludwig, DVD-Audio's potential fidelity is undermined somewhat by manufacturers' implementations of players. “DVD-Video maintains a huge advantage over DVD-A by offering stereo 24-bit/96kHz digital outputs to work with one's favorite audiophile D/A converter,” Ludwig says. “We are unable to use our converters with DVD-A players, which is a shame. The quality of the converters built into DVD-A players, like those built into DAT machines, are quite poor in comparison to a professional converter and unworthy of the format.”
WORKING IN BOTH WORLDS
Whatever the relative technical merits of the two formats for music applications, there can be little argument that DVD-Video offers an installed base that dwarfs that of the newcomer. Through the end of 2000, 14 million DVD-Video players had been sold in the U.S. alone, with the worldwide installed base expected to top 28 million by the end of this year. For that reason, many of the independent labels testing the DVD-Audio waters are choosing to combine DVD-Audio and DVD-Video on the same disc (made possible by the versatility built into the underlying DVD specification). The discs are designed to play as DVD-Audio in DVD-Audio and Universal players, and as DVD-Video in DVD-Video players.
“Most clients want the high-resolution audio that DVD-Audio has to offer,” Lee says, “but also want the backward compatibility of DVD-Video. To cover the widest installed base, every title we've produced is a hybrid DVD-Audio and Video title.”
As an example of this phenomenon, Alexander says that one of PDSC's DVD-A clients, 5.1 Entertainment, already has a catalog of music DVD-Video titles. The titles are now being reissued as DVD-Audio discs that incorporate the original DVD-Video content.
Not surprisingly, covering two formats on one disc can complicate the title preparation process for DVD-Audio, which is already far more complex than that of CD. Depending on the types of titles and the production workflow, the various engineers involved will have to be familiar with a range of tools that used to be foreign to the production of audio formats.
“Our menu designs — static and motion — are completed using Discreet Edit and Combustion, Adobe After Effects, Adobe Photoshop, and 3D Studio MAX,” Lee says. “Video and motion menus are encoded using hardware encoders from Optibase and Sonic Solutions. DVD-Audio authoring is done with Sonic DVD-Audio Tools, and DVD-Video authoring is done with Sonic Scenarist. We also use Macromedia Director, Visual Basic and Interactual PC Friendly to produce DVD-ROM content.”
DVD-A is not something that you can just easily add to your existing mastering facility. The way it is now, it is complex, costly and time-consuming.
— James Moore, Metropolis DVD
Clearly, there's a lot more going on here than in the typical audio mastering scenario. Of course, the entire process of DVD-A title preparation need not be handled by a single individual. In fact, in a high-throughput facility, the norm will be different specialists handling the various phases of production: An audio engineer will master the title's audio, video engineers will prepare and encode any motion video content, and graphic designers will create still images and the “look and feel” of menus.
The person in charge of pulling all these elements together is the title's author, a specialist in interactive multimedia who defines the menu structure and navigation and outputs the final master that goes to the disc replication plant. “The authoring engineer for a DVD-Audio title,” Lee says, “needs to know the extremely complicated DVD-Audio and DVD-Video specifications inside and out.”
A LONG AND WINDING ROAD
At PDSC, the title development process begins with the client, working to develop navigational flowcharts describing the behavior and functionality of the disc. These serve as a blueprint for authoring. At the same time, project elements created outside the facility are delivered to the various departments in their required formats.
Alexander says that PDSC's audio studio captures audio from many digital source formats, including Sonic Solutions HD sound files, Euphonix R-1 formatted sound files, Genex 8200 MO discs, .WAV files and .AIFF files. The studio converts these formats to PCM and is also equipped to encode to the Meridian Lossless Packing (MLP) format, which allows DVD-Audio to play back 6-channel, high-resolution sound without exceeding the available bandwidth of just under 10 Megabits per second. The studio also handles Dolby Digital (AC-3) encoding, decoding and watermarking.
Video normally comes in on digital formats such as D-5 or Digital Betacam; D1 and DVCPro are also accepted. Encoding to the MPEG-2 format used in DVD is accomplished on a three-pass Panasonic video compression encoder.
As for artwork such as still graphics and menu backgrounds, Alexander says it can be supplied in a number of formats, and that color hard copies should be included for reference. “Our design group has full creation capabilities for development of static, motion and animated menus,” he explains. “We can either create menus in-house from scratch or make minor changes for clients who prefer using outside design vendors.” The design group also verifies that artwork meets the proper specifications for DVD-Audio, taking into account such factors as the resolution, color saturation and overscan (safe area) of the NTSC (or PAL) television system.
Once the incoming elements are distributed to the proper departments and encoded, the resulting “elementary streams” (audio, video, still images and overlays such as lyrics) are quality-checked by a QA technician and/or the client. “If any corrections are needed,” Alexander says, “project management will contact the client to discuss possible solutions. Depending on what needs to be corrected, the appropriate group will be contacted and the changes will be applied to the project. At that time, the client and/or a QA technician will review any changes and submit an approval.”
When the project's elementary streams are approved, they are posted to a server and the project is assigned to an authoring engineer. Authoring procedures, Alexander explains, mainly consist of creating title structure and menu navigation, setting pre- and post-commands, and defining color palette, start-up logic and default player settings. Then the project is formatted by the authoring system into a DVD disc image, which is reviewed for any violations of the specification. “If the verification software finds any violations,” he says, “corrections are made to the project while maintaining the original disc behavior that was approved by the client.”
A verified disc image is then burned onto a DVD-R, which is submitted to the QA Group and to the client for preliminary testing. “The testing consists of a linear pass of all audio and video elements,” Alexander says, as well as “complete navigational testing of all menus and pages with reference to the flowcharts supplied by the client. A checklist describing the specific behavior of disc functionality normally accompanies each QA test of a project.” If corrections are required after testing, then the project will be resubmitted to the appropriate department, rebuilt and burned again to a DVD-R for further review.
Once the QA group and the client approve the project, verification software is again used to ensure that the final disc image doesn't include any violations of the specification. A DLT tape is created with all of the necessary flags for CSS, Macrovision and CPPM encryption. Alexander says the current system available for CPPM only works offline: The DLTs must be dumped back to a hard drive, the disc image scrambled using the encryption software, the result uploaded back to DLT and the whole thing verified again.
At this point, the project is ready for replication of check discs. “The testing procedures that were completed on a DVD-R are now reapplied to the check discs,” Alexander says. “This provides more detailed information on disc behavior, functionality and player compatibility.” In addition to complete testing of audio, video and navigation, the disc is checked in several different models of DVD-A players. The discs are reviewed by the client as well, and when written approval is submitted, replication begins.
A DEMANDING PROCESS
With such a demanding process, it's clear that putting together a DVD-A can be fairly costly, which no doubt contributes to the majors' malaise. Of course, a Pure Audio disc, with none of the navigational or multimedia components to complicate preparation, is much less difficult. And even for multimedia discs, the process is currently more challenging than it really needs to be, because authoring tools for DVD-A are, so far, much less developed than those available for DVD-Video.
“The tools that exist today,” Moore says, “are very primitive. We're in dire need of proofing and programming tools that compare with those of other multimedia formats. DVD-A is not something that you can just easily add to your existing mastering facility. The way it is now, it is complex, costly and time-consuming.”
That situation may change as Sonic Solutions integrates DVD-Audio tools from Matsushita (MEI) into its well-established DVD-Video authoring systems. “With the acquisition of MEI DVD-Audio tools by Sonic,” Lee says, “we are hoping for a faster way to develop DVD-A titles. The authoring tools need to become more user-friendly. This will help speed up the development of current titles, though having an entire format based on a single supplier is a little scary.”
Better tools alone, however, are unlikely to be the crucial factor in DVD-Audio's success. Eventually, it will come down to consumers, and whether they've been adequately wooed by labels and hardware makers. “As the prices on players begin to drop,” Zagnit says, “we should see more people buying Universal DVD players as opposed to DVD-Video only players. Will it reach the acceptance level and achieve the sales pace that DVD-Video has attained? I sure hope so. But I don't know that anyone can say with any certainty.”
New-technologies editor Philip De Lancie is a freelance writer on media production techniques and technology, and is co-author of the book DVD Production from Focal Press.