FOR PRINT AND ELECTRONIC publishers, large and small, the compact disc recorder shows signs of becoming a must-have device, the laser printer for multimedia and electronic publishing. Even beyond that, CD-recordable (referred to as CD-R, and also called writable CD because of its write-once nature) is developing into the most versatile and cost-efficient removable medium for saving and transporting files of all kinds.
Electronic laser printer. CD-R shares both technical and functional similarities with laser printers. On the technology side, it shares with the laser printer the use of laser energy as a writing tool. (The lasers in CD-R drives burn pits, representing binary ones, by changing the reflectivity of points on a special dye-polymer layer of the blank, gold-colored, recordable CDs.) It is the functional comparisons, however, that are more important:
- Drafts and proofs. Like the laser printer, CD-R is used for drafting, revising and proofing of digital publishing files. Unlike the laser printer, however, for CD-ROM production there is no complementary higher-quality output, no imagesetter equivalent: A recorded CD-R disc has the same "resolution" and data capacity as a conventionally pressed CD-ROM.
- Short runs and masters. Once a publication is finalized, CD-R is a device for one-off or short-run production, and for creation of masters that can be replicated by technologies designed for higher volume production: photocopying and offset printing in the case of the laser printer, CD-ROM stamping ("pressing") in the case of CD-R.
High-capacity storage. Complementing its importance as a one-off and low-volume medium in desktop multimedia and CD-ROM production is CD-R's potential in print publishing. CD-R is now positioned to replace diskettes, magnetic tape, and Syquest and Bernoulli magnetic cartridges for many file-transport and dataarchiving functions.
In this article we will briefly explore all of these uses as they relate to both print and electronic publishers and their service providers.
There are several reasons for the seemingly sudden "arrival" of the CD-recordable medium. An obvious one is that it is piggybacking on the CD-ROM explosion, which is resulting in popular mass-storage media at very affordable prices. As CD-R technology has developed and matured, there have been steep price drops for CD-R hardware and for "premastering" software that copies files to CD discs. Also, there have been improvements in performance, compatibility and ease of use of CD-R technology. As the technology has matured, the capacity and durability of the recordable CDs have by now been well proven.
Installed base of readers is huge. CD-R drives write data to CD-R discs, which can be read not only on CD-R drives but on CD-ROM drives as well. With over 25 million CD-ROM readers now believed to be installed worldwide, a total that continues to grow, there is no other removable and writable computer medium, except the puny floppy disk, that has such a large installed base of compatible readers.
CD-R writers can also record audio compact discs, CDs playable on the huge population of CD-audio players. Like CD-ROM, CD-R derives economies of scale from sharing CD-audio components, media and manufacturing technology.
Discs are cheap. Blank CD-R discs, the writable-but-not-rewritable gold CDs, are now available for as little as $7.00 per 650-megabyte (74 minutes of audio) disc. The media price is about one-tenth of what it was at its introduction. The cost per megabyte now beats any removable digital medium, except for some tape formats.
Royce White, president of DataDisc, predicts the achievement of "5 and 5" pricing by mid-1996: $500 CD-R drives and $5.00 blank media.
Machines are affordable. It was only a few years ago that Yamaha introduced a CD-R recorder the size of a dishwasher; it cost $100,000. Today, there are models available to end users for less than $2,000, including basic CD formatting and file-transfer software. The latest CD-R drives are as small as the half-height CD-ROM drives in the current generation of desktop computers.
The CD-R hardware price will likely break the $1,000 barrier this year, with products from manufacturers as solid as Sony and Philips. CD-R hardware and software producers tell us that a $500 CD-R drive may well be available at some point in 1997, or before, depending on how many CD-R units the large-volume computer manufacturers decide to order.
Short runs are competitive. Low CD-R and media prices make CD-R increasingly competitive with conventionally mastered and stamped CD-ROM, especially for short runs. Because there is no up-front fee ($1,000 or so) for setting up and producing a glass master, the cost of producing the first units is lower for CD-R than for CD-ROM. After mastering fees, the per-disc price for CD-ROM, per stamped disc, is in the $1.50 area, compared with $7-$10 for the blank CD-R media. At those prices, CD-R looks competitive for runs of up to 200 discs.
In practice, however, the crossover or break-even point where the unit volume favors conventional CD-ROM over CD-R for a given title is somewhere between 15 and 100 discs, according to the many people in the industry we have talked with. In June 1995, the number 50 is most commonly given as the crossover; it is usually less expensive to produce up to 50 discs inhouse via CD-R than to have them pressed, in a given run. This crossover quantity has risen as CD-R media get less expensive, although conventional CD-ROM replication fees are also coming down. The assumptions you make about labor costs, etc., will of course affect your estimate of the relative costs of producing CD-R discs inhouse (or by a service bureau) vs. submitting the files to a conventional CD-ROM replication facility.
Turnaround is fast. Improved turnaround time through faster recording and automated disc handling is another factor influencing CD-R's growing popularity. Low-volume CD-R production has always had the advantage over CD-ROM in that it is done inhouse, avoiding shipping time in two directions and permitting the publisher to retain control of the process. CD replication facilities, like printers, charge a premium for quick turnaround. But if it takes an hour to record each disc, the turnaround advantage quickly evaporates as the run gets longer.
CD-R drives were originally confined to recording a CD in "real time," meaning 74 minutes per disc, the original maximum playing time of an audio CD. (The initial CD-R media actually had a
63-minute playing time and stored less data than a maxed-out CD-ROM. The 63-minute variety discs are still available). Today, quite a few machines write at twice, or even four and six times, that speed (commonly denoted as 2x, 4x and 6x recorders). On the fastest machines, this cuts the recording time to about ten minutes per disc.
Incidentally, there is no necessary connection between writing speed and reading speed. A 6x CD-R recorder can write a disc that can be read by a 2x CD-ROM reader, for example, or a 1x writer can produce a disc readable on a 4x reader.
Robotized disc handling adds to the faster recording speeds in making inhouse CD recording competitive. Kodak's Disc Transporter, for example, can automate the production of multiple CD-R copies. The Disc Transporter can insert and remove CD-R discs from the 6x Kodak PCD Writer 600, recording and labeling up to 75 CDs automatically at about six per hour, either in batches of identical CDs or as discs with unique content. It can turn out the recorded CDs overnight, having them ready for use during the time it would have taken to ship by courier the premastering tape or one-off CD-R to a replication plant for mastering and stamping.
Master-slave duplicators (in which one master writes to multiple slave drives) have also been introduced, such as systems from Alea and from Data Technology, using 4x drives.
Technology beats competitors. CD-R offers important advantages over competing removable media, such as Syquest or Bernoulli cartridges. CD-R offers a medium that is higher-capacity (until recently, approximately twice the bytes) and more robust (no head crashes or disruption by magnetic fields), yet is highly compact and weighs less for mailing. Furthermore, the chances of the recipient (such as your service bureau) having a compatible drive are much greater with CDs than with any other high-capacity medium. CD-R is in fact beginning to take on everything in sight, from paper to magnetic disk cartridges, magnetic tape, other optical disc formats, and microfilm, as well as its CD-ROM sibling.
Even after the discs serve their transport function, their compactness and longevity make them very attractive for permanent archiving as well. There is no need to expend time and money to transfer the files to tape.
Because of its faster access and superior durability, the CD-R medium can give tape a run for its money in many situations. Magnetic tape can be cheap and reusable, but files on tape take minutes to locate, and must be restored to a hard disk before use. CD-R files are immediately read as CD-ROM files, with no need to be restored to disc. Unlike CD-R, which should be stable for 100 years, tape is susceptible to disruption by electromagnetic fields and requires expensive periodic maintenance to "refresh" it, if used for data archiving. Having to remount, inspect, recopy or rewind tape periodically cancels its initial cost advantage for long-term storage purposes.
CD-R also beats alternative electronic formats in situations where access to massive amounts of archived data is desired on a "near-line" basis, or where inactive files are supposed to migrate automatically from a high-cost storage medium (hard disk) to a lower-cost removable one (magneto-optical disc, magnetic tape) according to a hierarchical storage management (HSM) paradigm. The jukebox technology to pluck a disc quickly from racks of hundreds of CDs now exists, in part because of jukeboxes developed for music CDs and karaoke. The CD-R jukeboxes also take advantage of advances in robotics used for other optical formats.
CD-R/CD-ROM jukeboxes are far less expensive per megabyte than other optical disc approaches, and more practical for the purpose than magnetic disk arrays or tape changers. Furthermore, CD jukeboxes can intermingle retrieval of CD-R discs and CD-ROMs. The Pioneer 5004 CD jukebox, for example, stores 500 CDs and has four CD-R writers. With media cost considered, it can plug into a SCSI port and provide access to 300 gigabytes of data for less than $25,000. An NSM CD jukebox, designed for faster access than the Pioneer, can select from up to 200 CDs. (CD-R and CD-ROM discs, by the way, cannot be read by any non-CD optical drives).
CDs even challenge analog media. Trends have recently made CD-R competitive with microfilm and microfiche, as well as with other forms of digital media. CD-R is challenging microfilm as the storage medium for digitized "source document" page images, and is staking a claim to be the replacement for computer output microfilm (COM), the still widely used medium for distributing and archiving the reams of computer-generated reports many organizations require.
The replacements for COM systems_computer output to laser disc (COLD) and, more recently, computer output to compact disc (COCD)_eliminate cumbersome microfiche retrieval and substitute electronic search and display of report data. Since they originate as computer data, COM and COLD reports are easily printed to disc as searchable character data and are indexed without need for a page scanning step.
The universal readability and low cost of CD-R has recently given it a strong boost against the alternative, albeit higher-performance, optical media, such as write-once, read-many (WORM) discs and rewritable magneto-optical discs, for microfilm replacement applications.
Perhaps the only medium that CD-R is not directly challenging on the desktop is the fixed magnetic hard disk, which is still superior in its data throughput, access time, and now even capacity, as well as rewritability. Not designed for true random access, with their spiral recording track rather than a sectored design, CD-derived media still suffer an inherent disadvantage compared with the high-performance magnetic disks used for primary mass storage, and do not compete in that niche. Other optical (laser-written and readable) removable media may still at some point appear on the scene to mount that challenge, but they will have difficulty being CD-ROM compatible.
Multiple sessions are supported. CD-R discs no longer have to be recorded in a single session, overcoming a serious drawback in the original recordable CD technology. CD-R was first implemented with a format standard (the Orange Book, Part 2, for write-once CD media) that permitted multisession recording but did not make it compatible with CD-ROM readers. Any data that were added after the directory, or table of contents, for the first session was written to the disc would not have been readable on the CD-ROM drives of the time, or at best might have been read as a separate logical volume.
As a solution, multisession standards were proposed by the "Frankfurt Group" of CD-ROM vendors. Kodak implemented a version of the standards on its Photo CD, which turned out to be the important pioneering use of the recordable CD medium. Kodak wanted the digital images scanned from more than one roll of film to be transferable to a given Photo CD-writable disc, but not necessarily at one time, and wanted all of the images to be accessible as part of the same volume.
The Kodak approach to defining multisession CD file systems has become the de facto industry standard. It allows the CD-ROM reader to consult the most recent directory, which lists files from previous sessions also, rather than looking only at the directory from the first session and ignoring succeeding sessions. Most premastering software now supports the creation of multisession discs on CD-R writers, and most CD-ROM readers made in the last couple of years can read multiple-session discs, though older ones cannot.
While a CD-R disc can be built in several sessions, it is still a write-once format. The data on it cannot be physically overwritten. But now that CD-R multisession recording capability is taken for granted, and media cost is low, the lack of erasability and rewritability of CD-R media is not deemed as crucial as it originally seemed it might be. Rewritability is in fact a negative feature for a distribution and archiving medium: Would you accept pencil or erasable ink for business documents and publishing purposes? And when was the last time you erased a file on a floppy disk?
While there are other WORM (write-once) optical formats that share the durability and imperviousness to erasure advantages of CD-R, other WORM formats have never been satisfactorily standardized. The media cost of other WORM formats is not competitive, and the installed base of readers is insignificant compared with the CD-ROM universe.
The main problem remaining with the nonerasable CD-R discs is now how to update the disc directory efficiently each time a file is written to disc. The multisession approach on the write-once CD-R medium imposes significant overhead each time a recording session is ended and the directory is updated; each time you close a session, approximately 16 megabytes of CD space are permanently consumed, in addition to the new files themselves, by "session gaps." This makes it not yet practical for all purposes simply to regard the CD-R disc as a big floppy.
A possible solution to the high overhead of multisession recording is ISO 13490, a proposed standard for "incremental write" in the CD-R world. Incremental write, which some CD-R drives and premastering software already support, will allow newly written files to be entered in the directory without rewriting the whole directory. When the disc is complete, the incrementally written directory may be closed, to be readable on multisession-compatible CD-ROM drives.
On-the-fly recording eases the task. CD-R recording systems initially required the creation of a physical image of the files in the appropriate CD-ROM file system format, such as ISO 9660, on a magnetic hard disk. Some premastering software permitted CD simulation on the magnetic disk, prior to "burning" the CD, to see if the format was in order and that the disc's performance was as anticipated, but creation of a physical image prior to recording required a lot of disk space and extra time.
Newer software permits formatting and copying files to the CD-R disc on the fly, "premastering" with a virtual image or logical map, but without a physical CD-ROM disc image on the magnetic disk. Premastering on the fly eliminates the time spent writing out the CD format twice, first as a hard-drive mirror image of the final product, with CD-ROM file headers, error correction code and special directory structure. Formatting on the fly also avoids needing the space on the magnetic disk to have the files present in duplicate, once in native format and the second time in CD-ROM format.
Now, some recent premastering software even allows simulating some aspects of disc performance and standards compliance with the virtual disc image prior to burning the CD-R disc, testing that previously required the physical disc image or "ISO partition" on the magnetic disk. Premastering on the fly plus this new simulation using a virtual disc can save time, improve turnaround, and save on the waste of blank CD-R media.
Fewer coasters. CD-R writers are turning out fewer coasters these days. (A "coaster" is a CD-R disc that has to be trashed, often because the computer doing the premastering can't deliver an absolutely uninterrupted flow of data to the recording laser, still a CD-R requirement.) The dreaded "buffer underrun" condition is being seen less often, because of faster PC processors and drives, hard disks that don't stop to recalibrate themselves as they heat up, larger buffers built into the recording units themselves, and smarter premastering software and disc firmware that can predict and correct error conditions before they arise. (On the other hand, 2x and especially 4x and 6x CD-R writers can present new difficulties, since it is harder for the premastering PC to keep up with them without a hiccup.)
Single medium supports many formats. One obvious reason for the growing interest in CD-R is the fact that CD-R discs and the recording hardware will work with a variety of data formats tuned for different purposes. The same drive, with different software, can record discs for different platforms and different applications, ranging from simple file transfer to a service bureau to a completed interactive title.
Among the different CD data formats that most CD-R machines support are the following:
- CD-Audio (Red Book);
- CD-ROM (Yellow Book), often with ISO 9660 file name and directory conventions;
- Mixed-mode digital audio and data discs, including the original data-session-first mixed-mode specification (not friendly to audio CD players) and the new CD-Enhanced audio-session-first (Blue Book) discs;
- CD-ROM/XA multimedia discs with interleaved data streams containing compressed digital audio (ADPCM) and other data types;
- CD-I (Green Book) the Philips CD-Interactive format;
- Video-CD with MPEG-1 video and audio (White Book);
- Unix-friendly CD-ROM formats, including ISO 9660 with the Rock Ridge extensions;
- Macintosh native file system format (HFS) and Mac file-friendly ISO extensions;
- Kodak Photo CD; and
- Hybrid forms of the above formats, combining two or more on a single disc. In some hybrids, data files can be shared across platforms, while in other hybrid formats data files must appear redundantly on the disc, once for each file system format that the disc supports.
How would you use CD-R? In the context of the publishing business, CD-R has four main functions, as noted in the introduction: creating draft and proof versions of electronic products; producing short runs of CDs; burning premasters for CDs that will be stamped; and using CDs as portable, high-capacity media for data storage. For these purposes, CD-R's potential is not just theoretical. Firms around the globe, in all kinds of publishing businesses, are already taking advantage of the technology, often for several of these purposes.
If you make use of Syquest or Bernoulli drives today, you're a candidate for CD-R. The exponential increase in the use of digital images, particularly color ones for print publishing, has fueled demand for inexpensive high-capacity storage, whether it is to archive scanned images or to transfer files to a repro house or printer.
Calendars. A typical example is Teldon International, one of the largest calendar publishers in North America. David Laninga, who manages tech support and training for Teldon's electronic prepress operations, has begun using CD-R to store Teldon's calendar art. The art is scanned with a Hell scanner and processed through Photoshop, often months in advance of being laid out and set on film. Teldon stores each job, often a year's worth of images for a particular calendar, on CD-R discs. Usually one disc suffices for a whole job, including both high-resolution separations and low-resolution viewfiles.
When it comes time to produce the calendar, the low-res versions of the files are read from the CDs onto a local hard disk and then flowed into Quark Xpress for page design. When it is time to output to film, the CD-R discs are loaded into a six-disc Pioneer CD-ROM changer (defined as one logical volume) and the high-resolution separations stored on CD are fed by the Color Central OPI server over the network to an Agfa SelectSet imagesetter.
Laninga notes that the 4x CD-ROM reader in the Pioneer changer can send the files faster than the RIP can process them, so the relatively slow data rate of CDs has not become a bottleneck, although some seconds may be lost at a point where the changer needs to load a new disc. If it had multisession-compatible CD-R writers, Laninga conjectures, Teldon might store the Quark files on CD-R along with the art, but at the moment they use single-session recorders and keep only the art on CD.
Studio photography. Another CD-R fan is Gerald Bybee, a commercial photographer in San Francisco and owner of Bybee Studios. Bybee, who has done pioneering work in digital photography, uses CD-R for both archiving and delivery to his clients. With premastering software Astarte Toast CD-ROM Pro for the Mac, Bybee writes files to discs with a Yamaha 4x-speed Smart and Friendly CD-R4000/MA drive. When his studio delivers a job to a client, Bybee includes on the CD not only the images ordered but also a demo of his wildly creative portfolio.
Bybee described to us his satisfaction with the technology. "We deliver high-resolution RGB files on disc, which the separation houses turn to CMYK. The ad agencies love getting the digital files and RGB proofs. We used to use Syquest cartridges, but that had size limitations and other problems.
"We are moving to Live Picture and its multiple-resolution format, IVue, which, among its other impressive features, loads rapidly from the CD. We are in the process of converting our whole library to digital format and will be moving to an SGI server with Power Mac workstations.
"We had been storing images on DAT (digital audio tape), but it takes too long to recover a file from DAT when you want to use it. With CD-R you just pop in the disc and open the file. And with the Smart and Friendly Yamaha 4x CD-R drive, we can write and verify a disc in, I would estimate, less than 20 minutes. We had some problems with certain brands of media on the 4x machine, but have found the Kodak medium works well. Also, you need a dedicated machine for premastering, to keep up with the 4x drive. We put our premastering files on a removable hard drive which has nothing on it but the files that are being copied to the CD. You need a clean drive and a dedicated machine."
If your product_whether it be a client presentation, business reference service, software or interactive game_will be supplied on a compact disc, then CD-R is a cost-effective method of producing interactive drafts of the product as it is edited and polished on its way to completion.
The U.S. Government Printing Office, for example, uses Dataware's CD Record premastering software to test and revise virtual CD-ROM images four or five times before burning a prototype CD-R disc. When feedback from the requesting agency revises the prototype, formatting on the fly speeds the creation of a new version. Once a one-off prototype is approved for production as a CD-ROM, the GPO sends the CD-R to the replication facility to be mastered and stamped. "That way," according to David McCloskey, GPO CD-ROM specialist, "the proof copy on CD-R is an exact duplicate of the final CD-ROM product, which both the customer and the replication contractor can be held to."
For example, the U.S. Budget CD-ROM ("only" 93 megabytes for the current fiscal year) is derived from the PostScript files used to produce the printed pages. The PostScript pages are distilled into Acrobat PDF files and indexed with Acrobat Catalog. The Dataware premastering program tests the virtual disc image before it is produced on a CD-R checkdisc. The cross-platform CD-R version, with the Acrobat Exchange/LE viewer and Verity search engine, is tested on both PC and Mac systems, but the pages themselves, having been approved for printing, are not proofread again.
The GPO also produces some titles on CD-R only, on demand, such as when a Congressional committee wants data from specific federal data tapes to be searchable on desktop systems, or when a small number of bidders for a given federal contract request the volumes of data they need to prepare properly responsive proposals.
At Dennis Publishing, a leading publisher of computer magazines in the UK, a Plasmon CD recorder and InCat Easy-CD Pro premastering software help develop prototypes of the CD-ROM "cover discs" Dennis now includes with some of its print publications. Often these discs contain software demos of games and multimedia titles submitted by the software publishers. After testing and revision, faster because it is now an inhouse process, a final "gold master" CD-R disc is submitted to the stamping plant for mastering and replication.
Because the CD-R recorders are getting faster, and the discs are inexpensive, publishers are looking at CD-R as an economical way to deliver products to a small audience of one to 50 customers. Before long, we expect to see the technology migrate into print on demand, with the front end modifying some of the content for each disc, allowing the publisher to create personalized CD products.
At Visual In-Seitz, a business-presentation firm in Rochester, NY, 20 designers working on Macintoshes collectively produce about a gigabyte of presentation materials per week for their clients. According to owner Bob Seitz, they draw on multimedia resource files served from hundreds of CD-R and CD-ROM discs loaded into Pioneer 6-disc changers, 18-disc changers and even a 500-disc jukebox on the Mac network. T1 data links to remote offices give designers at those locations rapid access to the same assets as their colleagues. And for every CD that is "near-line" (meaning on the changers or jukebox), there is an archive copy stored off-site for safekeeping.
The resource files contain a variety of art, photographs, logos, clip art, animation and music, some of it generated inhouse. "We do digital video editing, too, but that doesn't go to CD at this point," advised Seitz. "MPEG-1 is not good enough for what we need and wouldn't make life easier for my designers."
After culling material from CDs, Visual In-Seitz delivers presentations on CDs, also using CD-R. Typical authoring tools to make digital presentations with branching capabilities include Microsoft PowerPoint, Macromedia Director, Adobe Persuasion or Photo CD Portfolio. Seitz's group has also produced digital press kits, with formatted documents in Adobe Acrobat PDF format accompanied by digitized photographs. Many Visual In-Seitz CD-Rs are created with Kodak Build-It software, which sets up, in effect, a digital slide tray that can hold hundreds of photos for presentation support.
Once a presentation is ready, with material, index and playback script in place, the MacTopix premastering software from OMI writes the files to a CD-recordable disc using a Kodak CD-225 2x CD-R recorder, based on a Philips drive. "We need multisession capability now, so we're looking at Toast Pro (from Astarte) as a possible premastering tool also," says Seitz.
Software distribution. Software vendors are beginning to use CDs as a distribution medium for both documentation and software, and CD-R enables vendors specializing in niche markets to issue updates in short runs. For example, Xyvision, a supplier of page-composition and document-management software, uses recordable CDs to distribute its Parlance Publisher and Parlance Document Manager products.
"To illustrate Xyvision's use of CD-R, you can picture a big funnel with 36 different tapes going onto one CD-R disc. That's all kinds of media formats: floppy disks, 8mm tape, TK50, quarter-inch, cartridges, reel-to-reel . . . since we provide software for Sun and DEC and IBM and Macs," explained consulting engineer David Giusto. Instead of 36 different cartridge tapes, nine tapes for each of four Unix platforms, Xyvision put its Parlance software for all of its four supported flavors of Unix, plus the documentation, on one disc, producible on demand by CD-R driven by Dataware's CD Record premastering software. According to Giusto, the CD-R format drastically cut the customers' installation time compared with tape. Of course, shipping costs and storage requirements were significantly reduced, and the problem of finding the proper tapes for a given installation was eliminated. Savings in media costs alone (CD-R vs. 150-MB tape cartridges) were substantial.
"We daisy-chain two Sony 2x CD writers as 'slaves' to double our output. With Sony's fiber-optic link you can daisy-chain up to 16 slave drives," noted Giusto. "And we've helped clients go beyond on-demand CD production to actual CD-ROM mastering, sending the CD-R discs to be replicated. For our purposes, though, CD-R is a fine distribution medium. We figure that until we have more than two hundred sites to support, CD-R will work very well."
Across the country in San Diego, the XSoft division of Xerox is preparing its new SGML document-component-management system, called Astoria, with the help of CD-R. Beta versions of the software are being produced every couple of weeks. The recordable CD enables XSoft to produce 10-20 new copies quickly.
To get out a new version of the beta software for testing, software engineer John Malo uses a Smart and Friendly CD-R 2000 recording station with GEAR premastering software from Elektroson, running on a Sun Sparc-5 and creating CDs in ISO 9660 format with Rick Ridge extensions, readable on either Windows or Unix systems. Malo beamed about the durability of the media: "To date we haven't had a single problem with a CD being damaged in shipment or arriving in unreadable condition, something we used to experience with tape."
The CD-R technology beats tape for beta software testing, but for backing up large amounts of data on a Unix network, Malo still relies on the higher capacity of tape. However, he does use CD-R to capture the software environment of a given customer so that it can be emulated as needed, either for software development and testing purposes or for support.
With things changing so fast, what is the danger of obsolescence with CD-R hardware or the premastering software? Are more big changes coming that might make it prudent to wait?
The answers are "not much" and "no." Things will always be changing in the computer industry, but if you have a good reason to buy CD-R, now is a good time. The technology has reached a stable plateau, and the next big changes are still a way off. Here's a look at what to expect.
Will CD-R drives be bundled with computers? Peter van Eijk, senior program manager for Philips Laser Magnetic Storage, predicts that CD-R will replace CD-ROM drives in the "P6" generation of desktop systems, systems based on the successors to the Pentium, scheduled to begin to appear in a matter of months.
Other industry participants agree that as prices of CD-R units fall, they should begin to appear in servers and high-end desktop units, perhaps in place of CD-ROM readers. Note that CD-R drives can read CD-ROM discs as well as record, but as readers they often are at a disadvantage in access time because of their heavy laser heads.
The effect of bundled drives will only be to lower the price, keeping CD-R competitive with some of the newer technologies described below. Even though the price may fall, the cost today is already very affordable and might easily pay for itself before the next dramatic price break occurs.
Erasability: Here, even now, sort of, but . . . . As we have seen, there are good reasons why erasability and rewritability are not needed for many compact-disc applications, where write-once CD-R will do just fine and permanent recording can be a positive feature, not a drawback. Erasability, however, would make it easier for applications to write to a CD disc as if it were just a big floppy, and make premastering easier to subsume transparently under operating-system file transfer and formatting utilities.
Formal CD-erasable (CD-E) standards are under development. Philips has proposed one that has garnered the support of ten leading hardware and media manufacturers. But before such standards can be developed to maximize compatibility with the CD-ROM world, there is already a CD-look-alike erasable format becoming available, perhaps even as you read this, in North America. These so-called PD, or PD/CD, discs are sectored, like computer media. They use phase-change rewritable media on which the reflectivity of pits and lands is changed by the laser's heat through conversion of these points on the photosensitive layer from an amorphous to a crystalline state and back again. The PD drives are made by Panasonic (Matsushita) and by NEC, with media available from Matsushita and Plasmon.
Even on introduction, PD drives are less expensive than CD-R. Internal PD drives are only $750, though available solely in small quantities. Importantly, they can read conventional CD, CD-ROM and CD-R discs, but, although they have the same dimensions as CD, the new erasable PD media cannot be read on CD-ROM or CD-R drives because of their differences in reflectivity, concentric (vs. spiral) format and different file system. At the monent, erasable PD media cost about $60 each, several times as much as write-once CD-R.
If they can be made inexpensively enough, PD drives could replace CD-ROM drives in some PCs before CD-R does, serving as a dual-purpose CD-ROM reader and tape drive replacement. For backup and archiving, CD-ROM compatibility of the PD discs won't be crucial, if the drive and media prices are low enough and the more CD-compatible CD-R stays relatively more costly for a while. PD/CD will have direct operating-system support in Windows 95, unlike CD-R, which also will lend itself toward bundled drives.
Despite its expected advance, PD's incompatibility with existing readers makes it much less interesting than CD-R for publishing applications.
Ultimately, what everyone wants is a multifunction drive that can read any CD flavor_read-only, recordable and erasable_and write to either write-once CD-R or rewritable (erasable) CD media. There already exist such multifunction optical drives in the 5 format, but they are unlikely ever to achieve the kind of success that CDs have.
It will take some time, however, to develop an erasable format compatible with CD-ROM readers and to modify CD-ROM software drivers appropriately so that it can be read. Don't hold your breath. Higher-density writable formats may appear first, changing the whole picture.
Higher-density CDs: Which, and when? For the past six months, Sony and Toshiba have been spearheading a war to set the standard for the inevitable high-density, read-only digital video disc CD that will replace VHS tape and analog laser disc for home-movie distribution. Sony and its allies have proposed the Multimedia CD (MMCD), now described as holding 7.4 GB online in two layers of the same disc side. On the other side, Toshiba, Time Warner and their allies are pushing the SD, or Super Density, disc, with 9 GB online in its most recently described double-layer format.
The two groups vehemently disagree over which format is most readily able to be manufactured in quantity (both the media and the drives), which will offer the best movie picture and sound quality, which is most easily adapted for data purposes other than movies, and whether compatibility with existing CDs and CD-ROMs will be possible to maintain. The emphasis of the Toshiba group seems to be to conquer the home-movie player market by Christmas of 1996, setting a de facto standard à la VHS vs. Beta, while the Sony group is emphasizing the MMCD's usefulness in business applications as well as in settop entertainment.
Writable and rewritable high-density formats derived from either MMCD or SD are projected, but far from deliverable. The 1998 date is proposed for both a writable and rewritable MMCD. The SD camp predicts that a single-layer, 3.2-GB writable format ("SD-R") may arrive by 1996, and a phase-change 2.6-GB rewritable format ("SD-RAM") is projected. The SD projections sound optimistic, and, of course, the delivery of writable formats will be contingent on what happens on the read-only front.
The MMCD and SD efforts are aimed primarily at pressing movies and other read-only applications on disc, and secondarily at developing a recordable medium compatible with the anticipated large population of high-density readers. Meanwhile, in Japan, other efforts have been under way to develop the home digital video recorder of the early 21st century. For these devices, high recording capacity to capture hours of digital video, the television of the era, is a foremost consideration. Phil Storey, president of Plasmon Data, expects 10-GB and eventually 19-GB erasable disks to emerge from this video recorder effort, produced by companies such as Matsushita. That effort, which is still years from fruition, may become yet another electronic-publishing and file-archiving medium.
The bottom line on high-density writable and rewritable formats is that CD-R in its current format will inevitably be superseded at some point (unlikely before 1997), but, given its usefulness and price now, so what?
Will I still need premastering software? The answer is yes, at least until 1996, and possibly until 1997 or later. Premastering vendors and drive manufacturers agree that eventually we might see direct operating-system support of CD-R, but not in the Windows 95 initial release or in currently anticipated Mac, Unix, OS/2, Windows NT or Novell products. We seem doomed to need separate premastering software, not provided by the operating system. (Windows 95 will improve CD-ROM, including the Autoplay feature, automatically loading and running a CD-ROM inserted into the drive, but not CD recording integration with the operating system.)
Philips's Van Eijk notes that the CD-R drives themselves will have more intelligence built into firmware and will be less dependent for some functions on software drivers and operating-system functions.
------------Bernard Banet