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DVD, The Bad, The Ugly, and The Digital Pits
An Overview from DVD Super Audio Discs to PC DVD-ROM


How Far We Haven't Come


Francis Vale

 

In the Beginning: DVD's Jurassic DNA Howls Yet Again


In many high-end audio publications, writers and readers alike spill tons of ink, some quite acid, on the CD vs. vinyl subject. Some believe that those vinyl analog LPs still sound much better than what's on those shiny digital discs. This cliched cacophony in a vinegar cruet is all too funny, as these people, are, in fact, comparing a half-century old recording technology with an equally archaic digital playback system. For those who can no longer remember, DVD's ancestral DNA, the CD, was first introduced way back in 1982. In digital-dog years, fifteen or so circuits of the sun is equivalent to about three centuries.

Circa 1982, IBM/MS DOS PCs with an 8 MHz "Turbo" 8088 CPUs were the rage. If you were really adventurous, your Fred Flintstone PC maxed out at 640 KB of RAM, and had a hard drive with maybe all of 10 megabytes. Today, your run of the mill Pentium Pro PC runs hundreds of times faster, costs thousands less, and has orders of magnitude more RAM and disc storage.

So, apart from chuckling over how far we've come, what would be the point of proposing a benchmark comparison between that digital CD museum piece and the Pentium system? It would be ridiculous to even propose it. Similarly, how can two woefully obsolete systems like vinyl and CDs be compared in any meaningful way? (Are the stray electrons radiating from those glowing tube amplifiers--still a fave rave among many audiophiles-- an insidious form of retro-mind control?)

Fortunately, a few forward thinkers in high end audio want to change this sadly ancien situation. Some, for example, have proposed HDCD (High Definition CD, developed by Pacific Microsonics), with its special encoding scheme, as one solution. But this HDCD still just a variant on the more than decade old 16 bit CD format. Others, like Bob Stuart, the CEO of Meridian (which is headquartered in the UK), have looked further out, and suggested that we just get on with it, and scrap that antiquated 16 bit, 44.1 kHz CD clunker. Since mid-1995, the Acoustic Renaissance for Audio (ARA), a group of industry experts chaired by Stuart, has been calling for a new CD "SuperDisc" audio standard (aka, HQAD, or High Quality Audio Disc). The original HQAD, as envisaged by ARA, had the following essential characteristics:

a) Losslessly compressed, linear PCM (packed) audio would be used. This lossless scheme is quite distinct from the lossy-compressed (data-reduced) channels such as those used by MUSICAM, MPEG Audio, PASC or AC-3.

b) The ARA proposal called for a 16 to 24-bit dynamic range, and featured either a 48 or 96 kHz sampling rate.

c) The new format would offer a choice of two to eight discrete channels. Each 48 kHz channel would normally be 20 bits, but up to 24-bits would be available; or you could use 16-bits, up to 24 bits, at 96 kHz sampling rates; or use some combination of both. This extended multichannel format would enable a full 360 degree spatial definition of the soundfield. And depending upon the tradeoff chosen between the number of channels, bits, and sampling rates, the recording playtime could be varied up or down.

d) It also offered two-channel compatibility with prior CD technology via the use of a dual layer disc. If you had a pre-existing CD player, you could play side "B", so to speak. Or if you had a new technology player, you could spin side "A" and get all the SuperDisc benefits. And quite critically, the retailer now only had to stock one disc for both generations of systems.

f) But perhaps most important, this technology would be cheap to implement, and to sell. Users would pay as they go, buying only the necessary hardware they needed to get the HQAD features they wanted.

Not to be outdone by the ARA, The Academy for The Advancement of High End Audio also jumped into the SuperCD act. This new group, which also includes a bunch of distributors and retailers, first "complimented" the ARA (always a tip-off to a rip-off) for making its proposal public domain. The Academy then went on to propose its own SuperDisc format, called High Density Audio Disc (HDAD), which was in many ways quite similar to the ARA's notions. The Academy's HDAD proposed 88.2 kHz and 96 kHz sampling rates; 20 to 24 bits resolution; and a minimum of six discrete channels, with up to as many as "the producer feels necessary to achieve the desired artistic goals." (Yep. Twenty-eight surround speakers and amps is just what this artist intended. Will that be cash or charge?)

Both the HDAD proponents and the ARA folks saw the new 5 inch DVD as the ideal carriers for these pumped-up, Schwarzenegger bits. So, missives were sent and presentations given to the Japanese Conference on Advanced Digital Audio (the committee in Japan which is also ruminating about using DVD as an audio-only SuperDisc). The ADA politely listened to everyone, and being Japanese, smiled, never said no, and then, naturally, came out with something quite different for a spec.

The ADA suggested that the makers of DVD electronics come out with a system capable of playing an audio SuperDisc having a frequency response up to 100 kHz; a dynamic range over 144 dB in the digital domain, and 120 dB in the analog domain; two channel sound, with multi-channel as an optional upgrade; and lossless data compression--but lossless techniques would also be OK. The new DVD players would also play CDs that met the Red Book standard. But, the ADA called for a single layer disc. Which means that the ARA's two layer proposal was out the window. And why did that happen? Because the Japanese consumer electronic makers are more interested in selling zillions of new DVD players than in preserving the installed base of CD players. So, if the ADA got its way, the retailer would now have to stock two different types of discs; one for existing CD players, and one DVD-audio for the new players. Music retailers would love that. Sort of like MiniDisc all over again.

Mickey Mouse Gets an Attitude

If all this SuperDisc sniping had stopped with just the ARA/Academy/ADA dust-up, then maybe some kind of audio-only DVD might have emerged sometime before the U.S. finally balanced its budget. But as it sadly, predictably, happened, the DVD itself is also embroiled in some nasty politics of its own, with two industrial scorpions ferociously encased in an ego-sized marketing bottle.

The entertainment industry, which long ago decided that atavistic, avaricious attorneys were a great substitute for technological progress, is in a to-the-death fight with the computer industry. The kings of Mickey Mouse have presumptuously laid down the law: Everyone of those forthcoming DVD variations, be it DVD-ROM drives for computers or ones sold for consumer electronics use, must sport a SCMS-style, anti-multi-copy mechanism. SCMS, in case you missed it, rhymes with scams. It is obnoxiously present on CD-R drives, DAT units, and on anything else that can make "perfect" digital music copy (which, as we are discovering, is also an oxymoron).

Now, up until the advent of this DVD brouhaha, if a device, such as a CD-R, was labeled as "consumer" product, it had to have SCMS. But if the very same device was destined for the computer "business" market, it got no SCMS. And the latter CD-R had 74 minutes of playing time--not a time-crippled 60 minutes like the product destined for the consumer market. The price of the consumer CD-R disc blanks also got slugged with "artist compensation" royalties. The industry logic was that every CD-Recording you made costs Guns & Roses, et al, another nickel. (Cassette & VCR tapes somehow missed this egregious surcharge. The lawyers responsible must have been shot at Sunset Strip sunrise.) But the CD-R blanks destined for the computer business missed this royalty bullet.

So what was driving the industry's DVD blitz for SCMS uber alles? In a nutshell, it was the tremendous capacity of a DVD. Full length movies could now be stored on a five inch disc. This was no longer Bob Dylan's pocketbook just at stake. Disney's was now also at risk of being picked. DVD thus represented a much bigger whose-money-was-in-jeopardy deal. Moreover, even the Hollywood lounge lizards could see that PCs were quickly on their way to becoming full blown, multimedia entertainment machines: consumer electronics or business PC, no difference.

And thus, the entertainment industry collectively harumphed, and said this bifurcated consumer/business labeling scheme had to go. No more silly Solomon splitting of markets. A DVD is a DVD, and so SCMS-type protection they all shall get. In DVD-ese, SCMS type schemes are instead called CGMS, or Copy Generation Management System (the scams-rhyming SCMS was probably too much truth in acronym for them). But at least SCMS condescended to allow you to make a first generation copy. However, under GCMS, even that gratuitous one copy gesture is dispensed with. Instead, the big Hollywood tyros have stomped down on their little ruby red slippers, and wailingly insisted that no copying--whatsoever-- will be permitted in their fantasy Oz of DVD.

But the reality is that the no second-generation-copy-allowed SCMS has not slowed down the Strasbourg fattening of the big bootleggers' Swiss bank accounts. E. g., the Chinese military generals and their multi-billion dollar piracy fiefdoms. If, however, an all American mom or pop is caught hot wiring a DAT's SCMS circuitry in the privacy of their basement, they are in for a true lobbyist-manufactured hell. At the behest of the industry, your solipsistic solons in the US Congress have passed anti-SCMS tampering legislation which provides for a cool $1 million dollar fine. (It's kind of like a reprise of the war on drugs: Lockup the users, but give zillions in foreign aid to the countries that produce the dope.)

Wisely, the computer industry long ago gave up on this hopeless anti-copy protection fight. Instead, it relies on ever-revitalizing itself and the market with new technologies (e.g., the current Internet craze). That such an embrace of rapid technical advancement--as opposed to maintaining a death grip on the brain dead SCMS--would be all to the good for the entertainment people is somehow lost on their Malibu beach baked cabezas.

Finally, the entertainment paranoids want to not only block digital to digital DVD multi-copying, but they also want to prevent digital to analog copies from being made! Why? Let's say you have a PC with an NTSC video board (which are increasingly common), and a DVD-ROM drive with a movie, or other such H'wood content. You could then pass the digital DVD-ROM bits through the D/A NTSC card, and out onto an analog VCR. You could thus supposedly make unlimited copies of ID4, and sell them from the back of your van at the nearest playground. Hence, the entertainment industry's hysteria over stopping such to D to A transfers. This is why that, in addition to CGMS, the Malibu Mob also wants to encrypt the DVD bits! This new crypto-addition to the DVD's already crowded alphabet soup is called CSS, or Content Scrambling System.

Until quite recently, data encryption was classified under U.S. export laws as being a lethal "munition." That's right. Data encryption was treated the same way as if you were exporting fuel-air bombs to Iraq. The US Dept. of Commerce has now taken over the job of chief commercial crypto-export enforcer from the Defense Department.. However, special crypto export licenses are still required, and there remains an ongoing battle between the computer industry and the US government. Many in the former camp view data-crypto export laws as still being much too rigid (perhaps you have been following this raucous and seemingly never-ending data security debate; e.g., the Clipper brouhaha). Now, in this techno-political context, if you consider that the encrypted DVD is meant to be a world-wide product, then the many legal and technical complications become quickly obvious -- All of this techno-red tape directly translates into DVD shipment delays.

No surprise, then, that the result of this tremendous inter-industry culture clash, and these restrictive governmental policies, is that not too many DVD movies, players, or DVD-ROMs were on the retail shelves last year. E.g., Sony and Philips, two principal movers pushing DVD, have announced they will not be shipping their DVD players until spring of 1997. However, their DVD manufacturing reluctance hasn't stopped other Japanese companies from charging ahead. Both Victor of Japan (JVC), and Matsushita Electric Industrial Co. were shipping DVD players as of Christmas of 1996 --but mostly for the Japan market. Hitachi, Toshiba, and Pioneer also were producing DVDs marked for Japan by the end of 1996. (Toshiba, and some other computer makers, further stated they were selling PCs outfitted with DVD-ROM drives in December '96.)

So who is going to buy these players in Japan--or the U.S.-- if there is no DVD software? Almost nobody. Then why would these DVD makers take such an apparently foolhardy action by shipping units in volume, so early? It's mostly a cultural thing. E.g., Mr. Sakon Nagasaki, Director of Matsushita's DVD-Business Planning unit, said at a press conference late last year that encryption "is a problem in the United Sates, not in Japan." Whoops! That remark must have had the Hollywood types reaching for the Maalox. (By the way, Japan is reported to have the highest rate of computer software piracy in the world.)

You Ain't Seen Nothin' Yet

But this DVD crypto-madness gets even better. It seems that the Japanese companies, like Matsushita and Toshiba, originally intended to put the DVD encryption scheme into a specialized CSS chip of their own design and manufacture. However, conveniently overlooked by these manufacturers was that, while their special function chip is a speed whiz at unscrambling the DVD bits, a general purpose computer CPU executing the software-only version of CSS -- even a big Pentium Pro -- would spend more than 100% of its time decrypting the DVD. This left the CPU with no time for doing non-essential things, like word processing, spreadsheets, etc. Strangely enough, the PC makers were not pleased at this wasteful prospect.

One obvious solution would be that, instead of using the all-software CSS, the special crypto-chip could be used in PCs. But using this special chip would add significant costs to the user. The PC makers therefore demanded that the software-only decryption scheme be redesigned with much lower CPU overhead. So Matsushita/Toshiba went back to the drawing board. Per some suggestions of IBM (so once again, IBM brings peace to the warring DVD parties ) they found a way to make it easier for your computer's CPU to handle all of the DVD decryption in software. However, even that revised software version still eats up CPU cycles (about 20% - 30%) that might otherwise be doing useful things, like running Doom. Still, running CSS decoding in software-only does open up the door to making it freely available to users, as opposed to adding in the cost of a specialized CSS chip set.

But even with this software-crypto-performance issue seemingly resolved, the PC makers still had a tough time getting their hands on a license to use these CSS codes in their DVD-ROM systems. It seems that Matsushita, which is the acting agent for handing out CSS licenses, was apparently more concerned about selling its crypto-hardware than about OEM licensing the crypto-software. The result was that Matsushita somehow didn't get around to rewriting its hardware-only CSS license to include the new software version. (Cynics might be tempted to say that Matsushita was more concerned about being first to market with its DVD, than about handing out licenses to its competitors.) Consequently, as of February, 1997, not a single US vendor was able to get a license for the software-only version of CSS from Matsushita. So, all those PC vendors who were busily designing new systems with DVD-ROM drives were actually flying blind -- Even mighty Intel was supposedly CSS license-less.

The computer people, who obviously have big problems with encryption (adds cost, user complexity, personal politics, standards fights, etc.), were therefore going completely nuts, and would have loved nothing better than to line all these perps up against the Hollywood Blvd. wall, and shoot them to DVD-CGMS-CSS-Crypto bits.

The ultimate irony is that most everyone in the industry agrees that some determined hacker will quickly find a way to crack the DVD crypto-scheme; which results, naturally, will then be posted all over the Internet in a matter of minutes And adding insult to injury, if this soon-to-be-hacked chip is used in a system, it will initially add several hundred dollars to the DVD player's retail cost. So why bother with this nonsensical exercise at all? Because it makes the inhabitants of the brain-dead land of Mickey Mouse think they are doing something useful.

But let's say that the computer makers and Matsushita finally kiss up, the software encryption scheme is cracked and nobody cares (unlikely!), and those spiffy new DVD-ROM PCs are on store shelves come this June (1997), it still won't help you much, because in about 7 to 9 months, they will already be obsolete. Last year, Toshiba announced that it was well ahead of schedule in releasing a rewritable version of DVD, called DVD-RAM. These new DVD versions, said Toshiba, will be in production come the beginning of 1998. But because the recordable versions of DVD discs have a different reflectivity than read-only DVDs, a DVD-RAM is not backwards compatible with a DVD-ROM drive. Slide a DVD-RAM disc into that barely six months old DVD-ROM drive of yours, and all you will get is a blank screen.

And unfortunately, this DVD screen play still has several more nasty, surprise endings in store for consumers. If a DVD movie on a PC is decoded via "free" software video decoder, as opposed to being done on another specialized chip, then this is what you can reasonably expect will happen, assuming you are using a 200 MHz MMX multimedia CPU from Intel. A typical movie will be encoded to fit on one side of a DVD disc, which means the average data transfer rate will be 4 to 5 Mbits/sec. That translates into about 24 frames/sec coming off the DVD, and onto your computer screen. But software video-decoding at that frame rate will eat up 100% of the MMX CPU's cycles. Should you also be using "free" software decoder for the movie's audio portion, then add on another 15% CPU overhead. And we aren't done yet. Using interactive branching between scenes, as would be done in training films and games (interactivity, after all, is the whole point of using a DVD on a PC), will add another 5% to 25% CPU overhead, depending upon navigation complexity. If you also want the software to do 3D audio processing, then you must add in another10% CPU overhead. Finally, be sure to add in the CSS software decoder CPU overhead of 20% to 30%. Total it up, and what have you got? An MMX CPU meltdown! That highly touted Intel MMX processor has now been crushed under a DVD multimedia load of 150% to 180%.

Obviously, even with the CSS software decoder issues resolved, there is little doubt that users' machines must have the complete suite of specialized DVD decoder chips if they are to avoid desktop meltdown. PC users will thus end up buying what are essentially full featured DVD players, like those sold in consumer electronics. That will add another $350 to $700 cost, depending on DVD features, to the PC--in addition to buying the premium MMX chip (which features are highly questionable for DVD work.) For example, Wired, Inc. announced in March that it is shipping its new $400 "DVD-to-Go," a DVD card with all the necessary decoder electronics. This DVD card is designed to go into the Apple PowerBook's 3400c's PCI slot. Note that this $400 does not include the DVD drive itself. For that, you will have to pay $200 to $300 extra. As the man said, there is no free lunch, software or otherwise. Worse, this expensive, first generation DVD system for personal computers will become obsolete in less than a year, when the new DVD-RAM appears on the scene.

Bur wait. There's more! (This article is beginning to sound like the TV infomercial from hell.) Also come 1998, High Definition Digital TVs will be on the market. Assuming that the TV makers and computer people pick the right HDTV format to support (the new HDTV "standard" provides for eighteen variations on this digital video theme), you still wont get the full benefits of HDTV viewing off your DVD. Even though the DVD makers are loudly proclaiming that DVD is "HDTV-ready," what they fail to tell you is that the current 500 line version of DVD (actually, it's 483 lines) only supports the "standard" digital TV resolution of 525 lines -- the true, 1080 line high definition resolution is not supported. In other words, DVD's current resolution, when played on a new digital TV, is not that much better than one of the old 425 line laser discs playing on your NTSC analog TV.

For DVD to support true high definition digital TV, its current format will have to be radically redesigned. Today's DVD sports 4.7 GB per side (or 9.4GB per side for a dual layer DVD). But HDTV DVDs will require 15 GB capacity per side--the minimum storage requirements for a typical 133 minute movie at true HDTV resolution. The huge increase in DVD capacity needed for HDTV means a big leap forward is also required in laser technology. To fill the storage bill, HDTV DVD's will necessitate scrapping the current DVD's red lasers in exchange for the new 400 nanometer "blue lasers" (like IBM's.) In addition, the present 4 to 5 megabit/second data transfer rate of DVD's (which can actually drop as low as 3.5 megabits/sec) will have to be dramatically upped. At a minimum, 14 megabits/sec is needed if a DVD is to support real HDTV.

Bottom line: not only will DVD-RAMs make your new, expensive DVD-ROM drive quickly obsolete, so will HDTV.

If there weren't so many billions of consumer dollars about to be burned up (not to mention furious consumers), you would have to laugh. Indeed, if this comical, absurd DVD story were pitched to a group of Hollywood executives, they would probably toss the film script out the door as being too ridiculous.

This is one Hollywood story where the upcoming sequel, featuring a recordable DVD that also supports the true high definition TV standard, will be a much bigger box-office hit than the original. But by the time this sequel appears, the DVD-movie popcorn will likely taste pretty old and stale in consumers' mouths.


Copyright 1997, Francis Vale, All Rights Reserved,

21st, The VXM Network, http://www.vxm.com

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