Dolby Podcast Episode 60 - March 26, 2009

Part one of a two-part discussion with Steve Venuti, President, and Jeff Park, Technology Evangelist, of HDMI Licensing, LLC, offering a deep dive into HDMI technology. In this episode, Craig covers:

1. Should you use the built-in speakers in your TV with your surround sound system,
2. How to get the most out of two-channel stereo content with Dolby Pro Logic, and
3. Great demo content picked by the experts.

 

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Craig Eggers: Streaming to your from our headquarters in San Francisco, this is Dolbycast, the insider's guide to entertainment technologies, from the experts at Dolby Laboratories. We're here to give you the straight talk and news on everything you need to know about technologies that excite your eyes and ears.

And we are back at Dolbycast. We've talked a lot about HDMI on Dolbycast in the past, and we've fielded a lot of questions about HDMI from our listeners. Today, to answer some of those questions, to really provide us some insights into HDMI, we have the experts on HDMI. Steve Venuti, good friend, is the president of HDMI Licensing, and he's joined by Mr. Jeff Park, who is the technology evangelist for HDMI Licensing.

Both gentlemen join us now here on Dolbycast. Gentlemen, welcome to Dolbycast.

Jeff Park: Thank you for having us.

Steve Venuti: Thank you, Craig. Good to see you again.

Craig: It's really great to have you here. Steve, you and I shared a couple of airplanes, a couple of hotel venues, burnt up a couple of components, in a worldwide tour about two years ago.

Steve: As I recall, maybe a couple of dozen...

Craig: [laughs]

Steve: But yes, yes we did. We set out to educate the world on HDMI 1.3, and appreciated Dolby's help in showing all the high-bitrate audio demos that you guys did.

Craig: Well, we appreciate it, too, and we were really glad to participate in that with you.

Gentlemen, again, thanks for joining us. We've got lots of great questions from our listeners. But before we do that, tell us a little bit about yourselves. Tell us about your career paths. How did you end up at HDMI Licensing?

Steve: This is Steve Venuti, the president. I ended up at HDMI Licensing. They brought me in to launch HDMI. The specification, or at least the 0.9 version of the specification, had been developed. The founders had been signed, the consortium had been started, and they were going to launch this to the public.

So my background is in how do you position and, to the end user, to the retailers, to the guys that are going to buy it, the installers, how do you communicate complex technology?

I had, in the past, kind of launched a lot of other technology products to the market, including, in the '90s, the Palm Pilot, NETGEAR's line of networking products.

Craig: Wow.

Steve: Acer's Aspire computers into the US. My background was always launching technology products. The Roomba was another one. How do you take robotics, and a failed product category like a little robotic vacuum cleaner, and make it work?

Craig: And it's very cool, by the way. It's very cool.

Steve: Well, I know. And I have one of the first ones, which is in my shelf right now collecting dust.

Craig: So, a distinguished career.

Steve: So, that was my job. So, they said, "OK, we have HDMI, which is a very complex technology. We want this to become a brand. We want this to become something people understand." So, they brought me in to launch it. I came in as the VP of marketing, and then, over the years, just last year, became the president of HDMI Licensing.

Craig: Congratulations. Jeff, tell us about yourself.

Jeff: Thank you, Craig. Thanks for having us. Basically, I have been in the industry of technology since about 10 years. I'm a little bit younger than Steve, so I don't have the variety of experience he does...

Craig: Better looking, too.

Jeff: Oh, thank you very much. Thank you. [laughs]

So, I've been part of the industry for a while, with working at LG, Cisco Systems. I was doing project management and product marketing type of roles, and developing new products and launching new products.

And, I joined HDMI Licensing about four years ago, at the role of technology business development, let's just say to educate the consumer market but also business and other aspects of the market, to really seed the growth of HDMI, to not only show the benefits of the technology but help consumers to understand, be able to kind of purchase and make the right decisions, and also help large retailers, like Best Buy, for example, to help them sell the product and have their workforce to really understand and be able to use the HDMI technology, to really help the market grow.

Craig: Got you. So, a lot of people associate HDMI with Silicon Image. And I guess the question is, how does Silicon Image differ from HDMI Licensing? Are they the same company, or different companies?

Steve: No, they are really different. Silicon Image had the technology that was the basis of DVI, which essentially is how do you take uncompressed video and send it over a digital interconnect. And, they then brought that to the consumer electronics market and rallied together a lot of large guys—Philips, Thompson, Panasonic, Sony, Hitachi, Toshiba, and then Silicon Image, formed the HDMI Licensing, LLC.

Craig: OK.

Steve: So, it was based on Silicon Image technology, but HDMI Licensing really manages the trademark and the specification and the adopters of HDMI, and the owners of HDMI are the seven founders. So, there's a close relationship, but there's also some independence that HDMI Licensing has. It really is there to manage the specification, which is on behalf of the seven founders of HDMI.

Craig: I see. So, for our listeners, before we get too far into this, HDMI stands for High-Definition Multimedia Interface?

Steve: That is correct.

Craig: And from my perspective, as an AV guy, obviously, we can transport great HD signals. We can transport, with HDMI 1.3, Dolby Digital Plus, Dolby TrueHD bitstreams. But it's also my understanding that there is a lot more that can be transmitted via an HDMI cable than just audio and video signals.

Steve: So, that is correct. The primary goal is to transmit, in the highest quality, uncompressed video and audio signals. So, you get the highest fidelity of audio-video. That's the primary goal.

But, this is a digital and a very, very high-bandwidth interconnect. And, it also is a two-way interconnect, in that it's not just one-way sending audio and video from a DVD player source device to an HDTV. There is communication going back and forth. And, you'll see more and more communication going back and forth.

So, we liken it to the days of analog versus digital phones, and what happens when you really had a digital, mobile technology, and what you could all of a sudden do in terms of the data that could go back and forth. And, that's what you'll see in your AV stack as well.

So, right now, we've got controls and control signals going back upstream. So, the TV, for example, is constantly telling the DVD player or the set-top box, "This is who I am. This is what I'm capable of. So send me the content in the right format and in the right resolution to make this the best quality and easiest consumer experience possible." So, those things are going on now.

And in the last couple of years, something called CEC, which stands for Consumer Electronics Control, is also being deployed, which is a set of protocols that provide system-wide intelligence. So now, if these components have CEC on them—and it's brand-agnostic, doesn't matter what brand deploys it since this is a standard—the DVD player, you could press "on" on the DVD player. DVD player sends a signal down to the TV. TV says, "OK, I need to wake up. I need to set to this input. I need to set to this." Everything's kind of automatic.

Craig: So, it's called CEC, but I think some manufacturers actually implement it with their own brand name. Is that right?

Steve: And that is correct. You really see CEC being deployed not only in kind of the basic CEC commands, but a lot of the brands are putting their own stuff on top of that and calling it VIERA Link or BRAVIA Link or AQUOS Link, or SimpLink in LG's case, or AnywhereNet in the Samsung case. So they are kind of branding it under their own names.

Craig: So Jeff, it sounds like it's really sophisticated. It's more than just audio and video. It's about communicating between the devices to get the very best possible experience.

Jeff: Correct. One thing I want to elaborate about CEC is that CEC isn't just a simple, like a remote-control, pass-through type of system. It also has what's commonly known as task-based commands. So, typically, if I press one thing I want to elaborate about CEC is that CEC isn't just a simple, like a remote-control, pass-through type of system. It also has what's commonly known as task-based commands. So, typically, if I press "play" on a device, it will just send that one command to a device, via IR port or some sort of a control mechanism like a Crestron system, whatever it might be.

But with CEC, what you have is task-based systems. For example, one-touch play. So, if I have a DVD player, for example, instead of turning on the DVD player, turning on the AVR receiver, turning on the TV, switching the correct inputs and outputs, and finally pressing "play, " having that content play, within a CEC environment, with a task-based command. Like a one-touch play, you just press "play" on the DVD player...

Craig: So, it's like a macro, then, almost.

Jeff: Exactly, but it's built into the system. So there's no fiddling with universal remotes and remembering the twenty commands you have to program into your remote. All you do is have the system that supports this feature within the HDMI CEC environment. Pop in a DVD, press "play," everything automatically just pops up and turns on.

Craig: So, you press "play" on the Blu-ray player, and the TV set might select video two and...

Jeff: AVR receiver will turn on, switch to the correct surround-sound mode, whatever you set initially for your Blu-ray player.

Craig: That's an interesting question. And it takes us to another point, though. What if I have two devices that might be connected that are on at the same time?

Jeff: Sure, sure. If you have multiple devices, what it does is it remembers. If you press "play," for example, on a Blu-ray player, and you're watching ESPN, for example, what it does is it assumes that you are trying to play a Blu-ray player because you have turned that on and pressed "play." So it has some intelligence at kind of guessing that.

And let's just say, if you turn everything off in the middle of, say, watching a Blu-ray, what it will do is, when you press "play" on the Blu-ray, it will go back to the Blu-ray because that was the last task you performed on that device.

Craig: So Jeff, we talked about Blu-ray. We talked about AV receivers. We talked about display devices.

Jeff: Sure.

Craig: I know that there's set-top boxes out there now with HDMI. What other types of products do you envision will have HDMI, or do have HDMI already?

Jeff: Sure. There's many products. For example, laptops these days. It's very difficult to find a laptop with Blu-ray that does not have HDMI, and it's growing very fast. Even netbooks that we see a lot in popularity these days, those small, ten inch laptops, eight inch laptops, they're even coming out with HDMI ports, because these chipsets are getting so powerful.

And most people don't realize that the cell-phone manufacturers now, especially during the Barcelona Mobile Conference they just recently had, showed a range of products, mobile devices, that were capable of outputting 720p out of a cell phone, via HDMI.

Craig: And hand-helds are becoming more of a multimedia experience as opposed to just a phone.

Jeff: Correct. Exactly. A lot of portable media players, similar to like an iPod or a Video iPod, whatever that be, but from third parties, that have HDMI outputs. So it enables you to kind of have an all-in-one device, not only for your home, for high-def content, but also carry it with you to watch the content wherever you are.

Craig: So if I have a laptop and it has HDMI, a simple connection from the laptop to my display device and, voila, instant picture?

Jeff: Exactly. Because HDMI, again, as Steve mentioned, has the bidirectional communication, where the devices discover each other's capabilities. Say I have an old, 2002 plasma that only does 720p. If I plug in a laptop, the laptop will know, because the TV itself will report, saying, "These are the only resolutions I support. And I prefer 720p." Those type of information is available in every HDMI TV. And the laptop will be smart enough to recognize that and send the proper resolution with no configuration required.

Craig: So Steve, think about the future for just a second. In a perfect world, where all these devices are connected together via HDMI, what's the promise of HDMI? What do we have to look forward to, maybe?

Steve: Well, I think the overall promise, and we just kind of went through this exercise with the consortium, to kind of look at what our brand promise and what we stood for is to the consumer, and I think it's pretty clear. We stand for simplicity. And simplicity really has two facets to it. One is, a single cable does everything that all these other cables used to do, right?

Craig: Fantastic, isn't it?

Steve: And also, simplicity in kind of a plug-and-play, you just plug it in and it works. That's why the CEC and this kind of device configuration, kind of recognition and capabilities discovery, that all happens seamlessly. And so that really is complex stuff. But the whole point is that the user experience is just: sit back and relax, and plug it in and it works. And it works to the best of the capabilities of the devices.

Craig: It's amazing. We need complex resources to make life simple.

Steve: That's exactly right.

Craig: And that's what HDMI does.

Steve: That's exactly right. You would be just blown away if you cut away an HDMI cable and you looked inside, and just imagine the stuff that's going across. The data rates that are going across that little cable are phenomenal, and what's happening. And yet it's all one cable, you plug it in, and it works.

Craig: And we talked about this during our worldwide tour. Not a couple of years ago, you had a component video cable, you had six analog audio cables to deliver high-resolution audio to accompany the video. That's nine cables, or ten if you think about it. Well, actually nine. And it's replaced by a simple interconnect that does so much more.

Steve: That does more.

So, back to your question about the future. Simplicity is something we'll always kind of think about in terms of what we do in the future. Reliability: it's all got to work. And then the last thing is performance.

One of the things that we are in is an ever-changing, very quickly changing world, which is frustrating and confusing to the consumer because we're in the constant dilemma of "What's next?" And you just seem to think that, "Wow, we've got this 1080p. I've got this beautiful screen. And then, what's next?" Something comes up next. That's exciting, and it's also challenging.

So, HDMI kind of plays in all those three fields. We deliver simplicity. It just works. Complexity that's really masked around the simplicity. It's got to be reliable, and it's got to have performance.

So, where are we going to be in two or three or four or five years? If you look at those themes, we're going to constantly look at how we deliver even greater and greater audio and video—I shouldn't say fidelity as much as I should say increased consumer experience, customer experience, user experience.

So fidelity is one way. You can always do more resolution. And we will. We'll do more resolution. We're getting into deep color, more colors, all that. But we're going to enter a world of 3D, for example, and that's not necessarily better fidelity as much as it is a whole, completely different way of experiencing this entertainment content that is going to require bandwidth.

Craig: No doubt about it, Steve. I mean, HDMI is going to be an important ingredient and an important component when we start to migrate 3D into the home.

Steve: And there's other things that we'll see in the future, too. Back to the message of simplicity, this one cable. Well, we're starting to see a consumer electronics world that is going to be connected to the Internet. So that's yet another cable.

So we announced at CES this year, you're going to see in the next version of HDMI Ethernet over HDMI. So that is going to allow for, number one, cable consolidation. You don't need all these devices. To get BD-Live, you don't need this device connected to the Internet. You only need one of your devices connected to the Internet, your TV, and it can act as a hub, and everything else will access Internet.

But you'll also then see that data path being used for all sorts of other things: more control, more sophisticated kind of control and upstream video and audio sharing and storing and things like that.

So, much more powerful, all over a single cable, a lot more performance. That's what you expect in HDMI.

Craig: And simplicity.

Steve: Absolutely.

Jeff: Yeah. And one thing I wanted to add is that this bidirectional networking capability can actually add, now, recording functionality via HDMI. Previous to this, you were kind of limited to just outputting content to the TV or AVR or whatever it might be. But now you can theoretically have a DVR or whatnot record directly from the TV's built-in tuner, instead of having an external tuner for the DVR.

Craig: Great stuff. Hey, we're going to take a quick break, and we will rejoin you here on Dolbycast.

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Announcer: If you have questions for the experts at Dolby Laboratories, email us at dolbycast (at) dolby.com. That's dolbycast (at) dolby.com. For more information and links pertaining to today's topic, be sure to log on to Dolby.com/dolbycast.

Craig: And we are back at Dolbycast with our very special guest, Jeff Park and Steve Venuti of HDMI licensing.

Jeff, I want to ask you a question. We spent a few months talking about the HDMI cable itself. And specifically the role it plays in the transporting these signals.

Talk about bandwidth for just a second. Tell us about the role of bandwidth and how it's important to an HDMI cable.

Jeff: Sure, when HDMI was first launched actually to go into a little history, HDMI was first launched back in October of 2003. And most people don't realize that HDMI the technology itself was fully capable of doing 1080P and eight channels uncompressed audio, back in 2003.

But, you then have devices that take advantage of that until recently. And that's why there was no distinction between a standard cable or high speed cable. So the difference is currently today the HDMI specification is fully capable of up to 10.2 gigabites per second of data transmission bandwidth.

So, what that bandwidth means is that you can carry different types of resolutions calling that whatever it might be. So it's a combination of things that fill up the bandwidth.

Craig: I was going to ask this question and you brought it up sooner rather than later. So let's get to it. When you go shopping for HDMI cables, , you see standard HDMI cables and some products are advertised as high speed HDMI. So what's the difference and why does it matter? Why should it matter?

Jeff: Sure. So first of all standard speed cables were initially designed for products that support up to 720p or 1080i worth of bandwidth. So a standard cable is designed for those type of connection.

So, for example, most satellite TV service or cable service are limited to 720p, 1080i outputs on their HDMI.

Craig: So if you have a 1080p display device, you need a high speed HDMI cable?

Jeff: Correct. So what I was going to transition into the high speed cable is once you go into a 1080p content, Blu-ray, some satellite service that have on demand 1080p content, since the cable has to carry that the amount of bandwidth data your cable has to be capable of handling that type of bandwidth.

That's why the creation of two categories of cables occurred because standard cables were designed for 1080i, 720p content. But once you moved up to 1080p or beyond even, up to 10.2 gigabits of bandwidth, you have to have a high speed cable, which was tested at that speed and makes sure it works at those type of environments.

Craig: So Dolby Digital Plus, Dolby TrueHD, will they travel over a standard cable or bit streams or do you really need to high speed cable to transport Dolby Digital Plus, Dolby TrueHD bit streams?

Jeff: So those will work with existing older cables. Standard speed cable, but you have to remember the combination has to be able to fit accommodate it by the cable. For example, if I have a standard cable, for example, and if I try to put 1080p plus Dolby TrueHD, that will not work obviously because the cable itself may not be able to handle 1080p.

Craig: On the standard cable.

Jeff: Correct. But if you had say 1080i, 720p and you had Dolby TrueHD going through it, then theoretically assuming all the devices within the chain supports it you should be able to handle that correctly.

Craig: So Steve, talk about quality for a second. Obviously quality always matters. How has it become of import when we talk about HDMI and the future capabilities as well as present capabilities of HDMI?

Steve: Well, HDMI is always stood for the highest quality. It is uncompressed. There is no conversion to analog and back. There is no compression. So it's always stood for the highest quality and it will always stand for the highest quality.

So we're really just a huge fat pipe that allows the audio and video guys to push through their content in the most pristine manner. So from that point of view HDMI will always stand for the highest bandwidth, therefore the highest capability to send the best quality over the link.

Craig: Here's a tough question, and we'll probably get to this a little bit later, too. Is there a difference between a $34 high speed HDMI cable and a $100 high speed HDMI cable?

Steve: That's one of the most common questions we get. So it isn't really a tough question. It's a very, very valid question. And let me put it this way, we have over eight-hundred and fifty companies that adopt and license HDMI technology. You can look at those companies and you can pick them out.

There are tier one companies. There are tier two companies. There are tier three companies. They all have a place in the market. So I'll liken it to a DVD player for the sake of comparison.

If you got a thirty dollar DVD player that's got an HDMI output, and you've got one-hundred fifty DVD player that's got an HDMI output. And those HDMI outputs are both compliant with HDMI and they have tested and they meet the compliance requirements, I make no judgment as to whether one is better or not.

From my point of view they are compliant. In the world of cables I make the same comparison. There are cables that sell for a lot. Let's just say a lot and there are cables that sell for substantially less.

In my mind if they are both compliant cables, I'm OK with that. I don't make any judgment as to the difference one or the other. Where I do make a difference, if they are not compliant. If they haven't been tested and they are selling for $10 and it's because they don't pay their fees and they don't pay their royalties and they haven't gone through testing, that's a problem.

Now let's get to the other cables, because there are cables out there that are let's say, two or three X the price of another cable. And they are both compliant. They are both legal. They are both from adopters. They both have gone through testing. So what could be the difference?

Well, that to me is up to the manufacturers to argue. When we test a cable, it goes into a lab. It plus in one end, plugs into the other. We look at the signal. It passes the signal to a certain strength, it passes the test.

We're not testing for durability. We're not testing for wrapping for a wall or something like that or shielding. We're not testing for a lot of things that could be very important to the consumer.

So that's where I think some companies choose to say, you know what, we're going to put more into our manufacturing. We're going to make this more durable. We're going to use these kinds of materials that cost more and we're going to go out on the market and we're going to say we're different.

Craig: That's certainly what makes our industry exciting.

Steve: Yeah, exactly.

Craig: Jeff, you had some thoughts about that.

Jeff: Yeah, so regarding cable what Steve was saying is there are other manufacturers just like in the PC world, they call the Apple tax. Certain brands might carry a certain premium, based on their reputation or there's a warranty or not be.

So there are many other factors, but as I mentioned earlier, at a compliance level, at a basic functional level, there is a standard speed cable and a high speed cable. Those are the two official categories.

Craig: That's what to look for.

Jeff: Exactly, but beyond that it's up to consumer and the manufacturer to decide what additional value-add that the cable might have, in addition to the baseline functionality that you have complied for.

Craig: So another question, in a single length run of HDMI what's the longest I can run in HDMI signal?

Jeff: So for copper, just a regular passive copper cable, typically it's a around on average about fifteen meters of length.

Craig: So that's forty, fifty feet.

Jeff: Yeah, forty-five, fifty feet for a high speed cable. For a standard speed cable since it is carrying less data, its actually longer.

Craig: Is that right?

Jeff: Yeah. Theoretically longer depending on the manufacturer. One thing I want to note is not every manufacturer produces cables exactly the same way. Every manufacturer has their own way of producing cables. So again, that may delineate the quality of cables between manufacturers.

Just because they have both passed a compliance on the cable, it doesn't mean every cable they produce is exactly the same for every front so.

Craig: Yeah, kind of an analogy. I remember back in the day of S-video when you couldn't run S-video more than six, eight, ten feet and the Monster folks came out with an S-video cable that went thirty feet. People said, you can't do that. gosh darn it, they did it.

Jeff: Exactly. Exactly. And we have seen a lot of innovations even just cable manufacturing. Steve and I just recently visited a manufacturer who showed off some great innovations even just putting together cables. So there is a lot of innovation going on and that's why you are going to see length grow as time goes.

Craig: So what happens if we exceed the length? What would I experience?

Jeff: So typically what you experience is pretty much no image because the signal in these...

Craig: And no audio?

Steve: No, audio, no image whatsoever. However, if the cable is borderline. Let's just say it's barely able to pass the signal, what you will see is if it's just riding that borderline, you will start seeing sparkles on the screen. So little white dots here and there.

Craig: So sparkles as opposed to maybe like the macro blocking which you experience...

Steve: Not as bad but kind of similar but the randomness is very random in dots and it's not wide spread. It's more, I would say, maybe ten percent of the pixels are changing into white dots. But again, this is not very common. It usually happens when you start running long lengths on a passive cable.

Craig: So what about this concept of converting HDMI to Cat5 because obviously you can transport signals longer distance over Cat5. And then possibly converting those Cat5 transported signals back into HDMI and into your connected device.

Steve: Sure there's a lot of great solutions out there for running long cables, especially for custom installs in homes and what not. And one of them as you mentioned is HDMI to Ethernet. Typically what they do is they take the electrical signal. So they don't really decode the HDMI signal, but they convert that electrical signal which is basically called a physical layer change to an Ethernet physical layer signal. They run it through two Ethernet cables, two Cat5 cables usually and convert it back.

They usually typically run about 200 feet in length and also there is other solutions out there beyond Ethernet, things like fiber, things like wireless, coax. There are many different solutions available but one of the nice things about these converted devices is that you can daisy chain these.

So, for example, if I have a HDMI to Ethernet solution that only goes two hundred feet and I have to go one thousand feet or two thousand feet, you can actually daisy chain these to create very long extreme lengths. And in our labs we have created a combination of different devices for HDMI to fiber, HDMI to Ethernet, active cable, passive cable and a combination of over one thousand feet and played PS3 games with no perceptible delay.

Craig: So, if I understand this correctly, we have fifteen meters, which is our maximum length...

Jeff: For passive cables.

Craig: Now, if I'm connecting devices together, so if my Blu-ray player is five meters away from a television set, my television set is ten meters away from my AV receiver, we're good. Is it fifteen meters between each connected device?

Jeff: Correct. So every time there is a ...

Craig: Maximum of fifteen meters.

Jeff: Sure, maximum of fifteen meters per connection. So what that means is if there is ever a electrical component in between any connection that electrical component kind of acts like a repeater or a booster.

Basically it takes the signal and it has to decode the signal and somehow if it's going to pass that signal along to say, a TV, if it's an AVR receiver it will boost that signal, clean it up and send it along within that chain.

Craig: Got you, but all devices in that connected chain are not equal are they? In terms of their processing capabilities, their communication capabilities. Is there a brains to the system? Or is may the brain shared between multiple connected devices. How does that work?

Jeff: Within the typical home theater environment if you have a Blu-ray player, a receiver and a TV, when it comes to connection how the content is sent, the source device decides how it is going to be sent out. So the source device needs to determine what devices down the chain and what their capabilities are.

So, for example, if I have a TV it needs to figure out what resolutions it supports and what it prefers. Then down the chain it would see AVR receiver and see what audio formats it supports and decide which format it's going to output through that connection.

Craig: So Blu-ray player is talking to the TV. Is the TV talking to the AV receiver?

Jeff: Yes, in certain cases, so in some home theater environments, because of the audio-video processing that's going on within the TV...

Craig: In the AV receiver also...

Jeff: Exactly, but what happens is since video data is so much bigger, sometimes the TV takes a few milliseconds longer to process that video than the audio. So what happens is within that case what you see as slight delay. So you hear the audio before you see the video on the screen.

Craig: Not good.

Jeff: Usually that is remedied by a manual delay setting on your AVR receiver which is typical. But it is very frustrating. I've tried it. So if you are watching like a soap opera or something you can tune it just right and all of a sudden you can watch sports or an action movie and everything is off because it's just a pure guessing game.

And one of the nice features of our HDMI is it has step by communication, a feature call automatic lip-sync. And what you are referring to is that the communication between the TV and the AVR receiver, the TV will report how long it takes to process video. So whether it be two milliseconds, 15 milliseconds, whatever it might be, and report that back to the AVR for that communication.

Craig: And then sync...

Jeff: Exactly, since AVR is in charge of the audio it will make sure everything is in sync with anybody who is downstream that might have a delay or may not but it would make sure it processes that properly with exact sync.

Craig: That's interesting because there are some Blu-ray players that are coming to market that I'm aware of that are going to have two HDMI outputs. The thinking, at least the thought process seems to be you take one HDMI connected directly to your display device. Take the other HDMI connected to your AV receiver.

Jeff: Sure. Usually those have a decoder built in. So like a Dolby TrueHD will be decoded directly within that device. And outputted usually by PCM, uncompressed audio, via the second HDMI as the AVR.

So it's kind of like having all in one, but giving you the flexibility to have external amp without having to go through a middleman, having the output both at the same time in synchronized mode.

Craig: I'm going to have to ask you to come back, but before we do that, you touched on the idea of repeaters. Can you give us some illumination on that? Are there amplifiers, boosters that you can put into the HDMI path to increase the length of the signal?

Jeff: Sure. So typically HDMI switch, for example, I just say that is built into the AVR. What it does is it takes the HDMI signal, decodes it and then re-boosts the signal with the active electronics built into that system. It sends it along. So it helps increase the signal level.

Craig: Now do you guys actually license the performance of those amplifiers, if you will?

Jeff: So, as long as the signal coming out of the device meets a certain criteria, there is no real performance based requirements. There's a minimum requirement, anything beyond that is up to the manufacturer to differentiate the product performance.

But what the repeaters basically enable devices to do if you have say, fifteen meter cable, you are right on the edge of connection. If you have a repeater device it basically has active electronics which boost the signal, clean up the signal.

So a copper cable is just pure physics. As it goes through the copper it just degrades in quality of the signal. It just works as a filter and that's the nature of copper. So what happens is once it gets to the repeater device, the repeater device takes that signal, reboosts it or amplifies it slightly in order to be compliant signal then outputs that again on the other side.

So you can run another fifteen meters theoretically to another device. This can happen, not just with a built-in device but also your AVR receiver, since it has those active electronics in them, it can also act as a repeater device.

And any device that has active electronics, whether it be a splitter, a distribution amp, a matrix switch, whatever it might be that sits in between your devices could actually help you increase the total length of your HDMI connection.

Craig: Jeff and Steve, some really great information and you know what, the problem is that we've got so many more questions for you. Would you kindly come back and speak to us in a future Dolbycast about HDMI?

Steve: We would love to.

Jeff: Absolutely.

Craig: Excellent. Thank you for joining us on this edition of Dolbycast. Remember you can contact us at 1-888-6-DOLBY-C, that's 1-888-6-DOLBY-C or contact us by email at dolbycast (at) dolby.com. That's dolbycast (at) dolby.com. I'm Craig Eggers. This is Dolbycast.

Thanks for listening. Talk to you soon.

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