Site created 12/15/97.
page created: 1/15/99
Thomson / Divx
Friday, January 8th
ProScan HD-Divx player.
definition ANTZ footage, encoded with Divx.
On Friday afternoon, I
was invited by Divx to their suite at Ceasars' Palace, to attend a
private demonstration of the Thomson / Divx HD-Divx system, which
had been officially unveiled on the eve of CES, by Thomson.
All of the equipment was prototype - existing technology that had
been heavily modified to conform with the new Thomson HD
architecture. Apparently, the technology was developed in secret in
the weeks and months leading up to the CES. Only a couple sets of
the hardware currently exist, for demonstration purposes.
Basically, this is how the system works. A standard ProScan DVD
player (an existing PS8680Z chassis) was modified to output a
high-definition bitstream. There was no blue laser technology or
special high-density HD-DVD disc at work here - this was a standard
DVD disc, with two very brief segments of high-definition footage
encoded on it: clips from DreamWork's ANTZ,
and a segment of nature footage, recorded at a full 1080i
resolution. The disc was encoded with the Divx encryption, and that
encrypted signal was passed directly out of the player. That's an
important point - the HD-Divx player has no internal decrypting on
board. Basically, it is simply designed to output the HD-Divx video
signal (with a special, dedicated output jack - think along the
lines of the DTS Digital Out used for DTS audio). In the case of
this demonstration, the encrypted signal was then passed into an RCA
prototype (I believe a 61"), high-definition-ready Digital TV.
Thomson has apparently decided that they will not support Digital
Transmission Content Protection (DTCP), which is the leading content
protection scheme favored by most members of the DVD Forum for HDTV.
DTCP would utilize FireWire connections between devices, and would
require "intelligent devices" at several points in the
signal distribution chain (including set-top boxes, etc...).
Thomson, who would no doubt like to sell a great deal of Digital
TVs, is proposing that a Divx-enabled SmartCard (compatible with
their own XCA architecture) inside the TV do the actual decoding. So
the content bit-stream is encrypted all the way into the display
device - what they believe is the most secure method of providing
content protection. Getting back to the demo, the encrypted HD-Divx
bitstream enters the TV, is decrypted by the TV's on-board
SmartCard, and the unencoded signal is displayed on the screen.
I'll admit, the Thomson / Divx content protection scheme is
compelling. Leaving the bitstream encrypted all the way into the
display device, does make it a more secure system. In this scheme,
Divx becomes only a layer of content protection, similar to
Macrovision. The important thing to realize here however, is that
this system renders every other device in the distribution chain "dumb"
- something the computer industry is certain to balk at. Moreover,
this demonstration is simply that - a technical proof-of-concept. In
the words of Divx president Paul Brindze, the purpose is, "to
demonstrate that it is possible to decode and display a digital,
high-definition, Divx-encoded signal in real-time. We're trying to
show that it can be done." There is no business model being
discussed as yet with regard to this technology.
Basically, (my opinion now) it was something of a publicity stunt -
to generate more positive vibes associated with Divx at CES. The
studios have not yet been approached with this concept (other than
DreamWorks, which supplied the clip), the rest of the industry does
not support it, and the odds of it being adopted by anyone other
than Thomson and Divx are very slight at this point, given all of
the expected industry resistance. But with this announcement, and
demonstration, Divx becomes more attractive to potential financial
partners. They can say, "look what we're a part of - we're a
very forward-thinking company."
Thomson and Divx are, no doubt, counting on the fact that many of
the Hollywood studios have already signed off on the Divx encryption
system - hoping that it will be a more appealing system of content
protection to them, than one created by the computer and electronics
industries, which have historically been at odds with Hollywood.
Said Brindze, "There is no one else, who is showing anything,
that will be acceptable to the studios in terms of security, to
deliver high-definition to the home. What the other schemes don't
provide, from a studio perspective, is security from the point of
the DLT (Digital Linear Tape) master, all the way to the viewer.
This system gives a full solution to the content provider."
Let there be no doubt - this system is an attempt at an end-around
of the DTCP proposal. A case of the various political factions in
the consumer electronics industry, vying to control the lion's share
of patients in the HDTV content protection system. And, should some
of the studios decide to support it, it will likely widen the
already vast gulf between Hollywood and the computer and electronics
Another important thing to note, is that there is no current,
agreed upon HD-DVD format. Divx's Brindze readily admits this - "There
is no public working group in the DVD Forum that is addressing a
specification for HD-DVD yet. There are private discussions going
on, but nothing substantial." Don't think for a minute that DVD
is likely to be usurped by HD-DVD anytime soon. The DVD Forum is a
long way from finalizing an HD-DVD specification. Again, this
demonstration exhibited no new real technological breakthroughs.
Blue laser technology, needed to store the increased high-definition
data on a DVD-sized disc (in feature film length quantity), is still
being perfected. Also, keep in mind - Hollywood has currently placed
a moratorium on progressive-scan technology in DVD players, until
their content protection concerns are satisfied. A solution to this
issue isn't expected anytime soon. And if you think Hollywood
resistance to progressive-scan is strong, it's nothing compared to
their content protection concerns over HDTV.
view of the HD-Divx player. Note logos
for HD, DTS and Divx, among others.
another view of the HD-Divx player.
Getting back to the
demonstration, you might be wondering how it looked. The answer is,
overall it looked great. Color, contrast and resolution were
outstanding, as is the case with most any high-definition signal.
There was a certain amount of digital artifacting, particularly
during transitions from one shot to the next, and during fast
motion. This is due to the fact that the video for this
demonstration was encoded at a flat bit-rate, using a real-time MPEG
encoder, as opposed to the standard, variable bit-rate, multi-pass
encoding process done with normal DVD. The encoding was done using a
local broadcast station's real-time encoder - not the kind of
environment needed for the highest quality. Currently, the
production environment that exists for DVD is not in place for high
definition, so the encoding, compression and authoring tools (not to
mention the talent pool and overall quality) aren't there yet. That
said, the visual impact was impressive. Divx claims that they could
fit an entire 2 hour movie on one DVD-9 disc, at 720p quality,
encoded at a flat bit-rate of 10 mbps (variable bit-rate compression
adds about 30% more data).
The encryption used was standard Divx Triple DES. The basic
difference here is that there the decryption must be done at a much
higher bit rate for the high-definition signal - greater processing
power is required than is needed in current Divx players (the
maximum bit rate for DVD is about 10 mbps, whereas for HD you're in
the range of 19.2 mbps).
Says Brindze, "Divx framed ourselves in a business position,
where the avid DVD crowd has looked at us as the dumbing down of
DVD. What we'd like to show you guys is that there are applications
for the stuff that we've done, at the highest end." According
to Divx, the cost of this technology would be relatively incidental,
given the already high price of such advanced TVs. "If you're
in the market for an $8,000 TV, the cost of the Divx layer would be
relatively insignificant. Thomson estimates that the cost of the HD
feature in the player, would be about $200 initially, and by the
time the technology is widespread, that cost will drop. The players
will still have to be fully backwards-compatible, so we're not
obsoleting anything. Also, this product will probably look more like
DVD, and not conditional access like the current Divx model. You
have to ask, how big will this market be? How many people will have
TVs, in this price range, that will do this? But, understand, that
we have no business model behind this yet. We'd simply like to get
ourselves accepted as the standard for HD content security, much the
same way that Dolby is the audio standard."
All of which is a nice plan, but ultimately there's a very long and
hard road ahead for the Thomson / Divx proposal to get to that
point, I suspect.
Thanks to Josh Dare, Paul Brindze and the Divx staffers who were on
hand, for taking the time to speak with The
Digital Bits, and to explain their HD-Divx demonstration.
to main CES '99 menu)