| Hometheaterphile July 2007
 HDMI: A Talk with
Joe Lee of HDMI Licensing, LLC
The first home-theater system I owned was a 5.1-channel
home-theater-in-a-box from Pioneer. It included speakers, a five-disc DVD player, and a
receiver, and cost about $700. I remember how excited I was as I ripped the plastic off
the small satellite speakers and the electronics: I was eager to install it all and get it
working. I placed the speakers where they looked best and shoved the electronics under my
TV. I’ve never been the kind of guy who reads instructions; I used the provided
manual more as a book of suggestions. Thankfully, Pioneer had intended that this system be
an entry-level product: the first home-theater purchase by a newborn enthusiast. The
receiver’s rear panel had color-coded inputs corresponding to the cables provided.
While those color-coded inputs made installation easier, I
still had a lot to do. Not every piece of furniture gives easy access to the rear panels
of electronic components, and now, with five sets of speaker cable, one subwoofer cable,
several component interconnects, a few digital RCA links, and six RCA interconnects for
multichannel audio, I faced the reality of my new home-theater enthusiasm: a big mess. In
the years since then I’ve spent a lot of time lying in awkward positions, pointing a
flashlight beam into a chaos of wires, searching for connections. Speaker binding posts
were the worst -- before I discovered banana plugs, slipping bare wires into the
posts’ little holes was torture.
Then it all changed
Last fall I received a review sample of the Anthem
AVM 50 home-theater processor. I already owned an AVM 20, but the AVM 50
has HDMI switching capabilities and the ability to scale video up to a resolution of
1080p. Until then, I hadn’t had the chance to employ HDMI connection to its full
capacity in my system. I’d used it to transmit the digital video signal to my TV, but
hadn’t yet used HDMI to carry the audio signal as well. Using a single HDMI cable
would take the place of eight cables. Setup was quick and easy, and the result was
much neater.
Before the AVM 50 arrived, I had read many forum
threads discussing the use of HDMI, threads dominated by complaints about the HDMI
handshake. It turned out I had some handshake problems of my own: My Toshiba HD DVD player
wouldn’t communicate with the Anthem. But the fix was simple, and Anthem’s great
customer service walked me through it: turn both units off, then power up the processor
first, followed by the HD DVD player. I was quickly up and running.
A few months later, after reviewing the AVM 50, I
decided to buy another Anthem processor. In coming to this decision I had to consider the
HDMI 1.1 specification, which the AVM 50 currently has, and the HDMI 1.3 spec, which
looms on the horizon. I began to search for someone who could answer my questions, and
ended up contacting Joe Lee, HDMI evangelist, at HDMI Licensing, LLC. Lee’s
professional experience includes nine years in product and retail marketing, business
development, and general technical knowledge of digital interfaces and semiconductors. He
earned a B.S. from MIT and an M.S. from Stanford University, both degrees in mechanical
engineering. Lee agreed to answer my questions concerning the past, present, and future of
HDMI, and how it will affect the industry.
Randall Smith: One thing I always I find it fun
to ask guys like you is whether or not they’re home-theater enthusiasts.
Joe Lee: Yes, absolutely! My passions extend to all
[consumer-electronics] and [personal computer] technologies. I am more of an audio
enthusiast than video, probably due to my background in musical performance and
production. I have a 55" HDTV at home with an HD DVR satellite receiver, and a 5.1
surround-sound system. I follow the trends of the latest A/V technologies closely, and
seek demonstrations of them at each trade-show opportunity so that I can determine for
myself the benefits of new technologies. I build my own gaming PCs, and am also an avid
(digital SLR) photographer.
RS: One of the biggest benefits of HDMI can be
realized by the new high-definition video formats, Blu-ray and HD DVD. Are you an early
adopter of one of these formats?
JL: No, mainly because: 1) I get more than enough
high-quality HD content than I have time to watch over broadcast (my frequent travel
schedule plus two small children limits my time to enjoy watching movies these days); and
2) I am waiting out the format war and waiting for more movie content to become available.
RS: Since HDMI 1.0 was released in 2002, there
have been multiple updates to the HDMI spec. This makes the consumer who owns or is
shopping for a new electronic component with HDMI very uneasy. What assurance can you give
these people that their new equipment will not soon become outdated?
JL: This challenge is something that is common to
any electronics industry, and not distinct to HDMI. For example, PCs are constantly
undergoing improvements to the CPU and graphics hardware, rendering older equipment
"obsolete" and unable to run new types of applications or games. Cell phones are
gaining new levels of multimedia and broadband performance, rendering older phones
"obsolete." HDTVs these days have higher resolution (e.g., 1080p) and
better and larger LCDs (e.g., wide color-gamut backlights, wider viewing angles,
faster response time), making older TVs seem similarly obsolete. These are natural trends
for all consumer products. The key with HDMI is that all HDMI devices are fully
backward-compatible, so no devices get left behind in terms of still being able to have
their highest capabilities experienced. HDMI’s revisions are made to keep up with
these trends in CE technology so that consumers have a connectivity interface that allows
them to experience these innovations, such as higher resolutions, Deep Color, new
surround-sound formats, higher refresh rates, etc. These revisions are not taken lightly,
or done with the intention of forcing consumers to upgrade equipment, but to provide a
framework for new and better A/V technologies to be brought into products. Given the
choice of delivering new technologies to consumers through new revisions, or of stagnating
the A/V experience by freezing HDMI, I think the consumers are better served by the
former. But if a consumer prefers the latter, they can simply purchase products supporting
the older HDMI revision feature set. We’re giving consumers the choice to make that
decision rather than making it for them.
RS: HDMI 1.3 is capable of delivering convenience
that doesn’t yet exist for consumer consumption. In your opinion, how long will it be
before the entertainment industry takes advantage of the abilities of HDMI? Will there be
a new HDMI spec before the capability of 1.3 is fully realized?
JL: If you look at HDMI’s past, the
specification’s fullest features have typically led the delivery of mainstream
end-user products by two to three years. Some examples are 1080p (available in December
2002 with HDMI 1.0, but not in mainstream TVs until 2004), and eight-channel, 192kHz audio
(also available with HDMI 1.0, available in AVRs in 2006). As for HDMI 1.3, we are already
seeing products that are taking advantage of some of the HDMI 1.3 capabilities now, such
as the PS3, which can support Deep Color. I expect that PCs will exploit the
high-resolution and Deep Color aspects of HDMI. PC monitors today already push resolutions
close to the limits of HDMI 1.3, and these would immediately benefit from the lower cost
of using a single HDMI link, compared to today’s DVI dual-link solution. This year,
LCD TVs supporting a 120Hz refresh rate will start shipping, which requires twice the
bandwidth to be transmitted over HDMI. Denon has announced an A/V receiver supporting
several aspects of HDMI 1.3.
As for the entertainment industry and content providers,
this is harder to predict in terms of a timeline. In our discussions with working groups
such as SMPTE [the Society of Motion Picture and Television Engineers], the broadcast
engineers tell us that broadcast will absolutely send native 1080p, Deep Color, xv Color
content at some point in the future, but it does require a change in the full ecosystem of
studio capture and broadcast equipment. So, yes, I believe that the entertainment industry
will take full advantage of HDMI 1.3’s features at some point. Given that the HDMI
specification has been revised every two years or less, chances are good that the HDMI
spec will be on its next revision before such major changes proliferate through the
broadcast industry.
RS: Will HDMI always be an interface hard-coded
on a chip, or will future implementations be programmable so that they can be upgraded in
the field via software if a new standard -- HDMI 1.4, 1.5, etc. -- is adopted?
JL: Some HDMI features require a hardware change;
others may be added through a software or firmware upgrade. The requirement for new
hardware to experience new features is not something that is unique to HDMI. For example,
PCs that want to enjoy the latest, higher-performance gaming features must upgrade their
graphics chip to DirectX 10.
Some examples: Deep Color requires a TV to have a different
timing controller, row and column drivers, and better crystal material capable of handling
the higher precision of Deep Color, so it cannot be added to a TV with a software change.
Lip Sync requires a minor change to the EDID ROM of a TV, so it could be a patch applied
to a TV. For an AVR, it requires the AVR to have an audio buffer circuit. An AVR that
already has such a circuit and a programmable microcontroller might be upgraded to support
automatic Lip Sync.
RS: Is there communication between the video
display and the source component to establish the version of HDMI each supports, and the
advanced features the source or display may or may not support (e.g., Deep Color,
etc.)? Or will end-users have to use a menu to tell the HDMI 1.3 source component what the
video display will or won’t support? And where does the compression, if needed, take
place?
JL: The HDMI revision number is relatively
meaningless from a functionality point of view because the vast majority of features in
HDMI are options. Instead, HDMI does indeed have provisions for devices to report which
specific features they support (such as Deep Color, xv Color, specific audio formats,
specific resolutions, etc.) in the EDID chip. In addition, the HDMI datastream contains
information packets that identify what specific audio and video format the data is in, so
that the TV or A/V receiver knows exactly how to properly extract the video and audio. The
basic architecture of HDMI is a device-communication system that enables fully automatic
plug-and-play with no need for users to manually configure devices, and a system that can
eliminate the possibility of getting a blank screen or no audio. Note that HDMI’s
video is always uncompressed. For audio, the information packets in the HDMI stream
identify what specific format (e.g., Dolby Digital 5.1, DTS-ES, etc.) is being
sent, so that the receiving device knows how to properly decode and present the audio
without any user intervention.
My take
After this interview, and after talking with Tom Dixon of
DTS, I felt comfortable enough with HDMI 1.1 to purchase the Anthem D2 processor. Knowing
that the HDMI spec is fully backward-compatible means that I also know that I won’t
soon have to replace the Anthem in order to enjoy the newer technology. HDMI has been out
for years, but only in the past year has the connection format been available in
commercial receivers and processors. This means that companies such as Anthem must spend
much of their design and development time solving compatibility issues instead of pushing
ahead to the future.
At this point, not all HDMI interfaces are equal, as I now
know from my own experience. The interactions of the AVM 50 with the Sony PlayStation
3 and the newest Toshiba HD DVD players, both of which have HDMI 1.3, are somehow
different. For example, I must first turn the processor on under the TV input, then switch
to the input for the PS3 or the HD DVD player. If I don’t, I get no sound from either
source. Anthem says that they have a downloadable fix for this issue, but it addresses
only one of the source players. But I don’t fault Anthem for this slightly irritating
bug; it’s just part of being an early adopter.
Ultimately, I think HDMI is the future of the audio/video
industry. Living with bugs is part of the growing pains any early adopter must endure, and
the ever-changing HDMI spec means that I will forever be upgrading. This is obviously good
business for electronics manufacturers, but it’s also one of the characteristics of
this hobby that keeps it fresh.
...Randall Smith
randalls@hometheatersound.com |
