Posts Tagged ‘HDMI 2.0’
Look Out, HDMI – Here Comes Super MHL!
- Published on Tuesday, 17 March 2015 12:38
- Pete Putman
- 0 Comments
Yesterday, the MHL Consortium announced its newest flavor of display interface – Super MHL (or, more accurately, superMHL). MHL, which stands for Mobile High-definition Link, was original developed to enable display connections over Micro USB ports on phones and tablets. You’ll find it most often on mobile devices and televisions from Samsung and Sony. It will also pop up on LG products and there’s even an MHL port on the Pioneer AV receiver I bought a couple of months ago.
There have been some clever demos of MHL applications at past CES events. One was to build a “dumb” laptop (no CPU or video card) – just keyboard, touchpad, and display – and use MHL to dock a smartphone into it make everything work. Another demo in the Silicon Image booth featured smartphones being used as video game controllers with the video playing back on the controller screen.
Yet another demo showed a Sony Experia phone being used as a remote control with a Samsung TV to select inputs, play video, and launch Internet applications. It’s easy to do this stuff when you can multiplex video and serial data through the same connector, which in MHL version 3.0 can even play back Ultra HD video at 30 fps with 8-bit color.
Note the emphasis on the “mobile” part. In the world of transition-minimized differential signaling (TMDS), MHL is one of a few players, the others being HDMI (the dominant digital display interface), its predecessor DVI (still going strong although the standard isn’t updated anymore), and Micro and Mini HDMI, niche connectors on smartphones and cameras.
The advent of Ultra HD, 4K, and higher display resolutions like the new “5K” widescreen workstation monitors use has created a problem: Our display interfaces need to get faster. A LOT faster!
But HDMI 2.0, announced in September 2013, isn’t fast enough. I get into frequent debates with people about why it isn’t, so let me clarify my position: HDMI 2.0 has a maximum overall clock (data) rate of 18 gigabits per second (18 Gb/s). 80% of that can be used to carry display signals; the rest is overhead using 8 bit/10 bit mapping.
So that limits HDMI 2.0 to supporting 3840×2160 pixels (4400×2250 pixels with blanking) in an RGB signal format @ 60 Hz refresh. That’s the hard, fast speed limit. For anyone using a computer workstation or media player with RGB output, this hard, fast limit is a serious obstacle: How will people who buy the new HP/Dell 27-inch workstation monitors connect them? Their working resolution is 5120×2880 pixels, and at 60 Hz, that’s just too fast for HDMI 2.0.
It looked like DisplayPort 1.2 would finally ascend to the top of the podium, since its existing speed of 21.6 Gb/s (17.28 Gb/s usable) was already faster than HDMI 2.0. And now, DisplayPort 1.3 has been announced, with a top speed of 32 Gb/s (about 26 Gb/s usable) and the adoption of Display Stream compression. Indeed, more computer manufacturers are providing DP connections on laptops: Lenovo seems to have moved completely to this format, and Apple has been supporting DP for some time now.
With all of that in mind, I will admit I was completely blind-sided by superMHL at this year’s International CES. Instead of a 5-pin Micro USB connector, superMHL offers a 32-pin, full-size connector that’s symmetrical (the next big thing in connectivity, a la USB Type-C). It also supports Display Stream compression. And it’s compatible with USB Type-C, although not with all six lanes. And it has a maximum data rate of 36 Gb/s across six lanes of data. (According to the MHL Consortium, that’s fast enough to transport an 8K (7680×4320) image with 120 Hz refresh and 4:2:0 color.)
The MHL Consortium’s announcement yesterday featured Silicon Image’s new Sil97798 port processor, which can also handle HDMI 2.0 signals. Here are the key specs from the Super MHL press release:
- 8K 60fps video resolution, as outlined in the superMHL specification
- New, reversible 32-pin superMHL connector
- USB Type-C with MHL Alt Mode
- High Dynamic Range (HDR), Deep Color, BT.2020
- Object audio – Dolby Atmos®, DTS:X, 3D audio, audio-only mode
- High bit-rate audio extraction
- HDCP 2.2 premium content protection
Whew! That’s quite a jump up from MHL. Some might say that superMHL is on steroids, but no matter how you look at it, superMHL is now a serious contender for the next generation of display connectivity. In the press briefing, a representative of the MHL Consortium waxed on about the approach of 8K broadcasting (it’s already been operating for two years in Japan) and how we would see a migration to 8K TV and displays in the near future.
As Larry David says, “Curb your enthusiasm!” Supporting 8K would be nice, but we’ve barely started the transition to UHDTV. And right now, selling 8K TV to the average consumer is like trying to peddle a Ferrari to someone who lives on a dirt road.
Where superMHL will find its niche is in supporting the higher bit rates that high dynamic range (HDR), wide color gamuts (BT.2020), and higher frame rates (60/96/100/120 Hz) require. All will shortly become important parts of the next-generation (UHD) television system. DisplayPort is already there with version 1.3, and you’ll even find DP 1.2 connections on selected models of Ultra HDTVs so that gamers can connect laptops and desktops at Ultra HD resolutions with 60 Hz refresh.
Now, the elephant in the room: How does the emergence of superMHL affect HDMI? Even though version 2.0 is over a year and a half old, you don’t see many HDMI 2.0 jacks on Ultra HDTVs. Casual inspections at Best Buy, HH Gregg, and other outlets show that the typical HDMI 2.0 port count is usually one (1), even as we approach April of 2015.
In the superMHL presentation, the concept of a TV with multiple HDMI 2.0 inputs and one superMHL input was outlined. This would, in effect, be the next step up from where we are now, with the typical Ultra HDTV having one HDMI 2.0 input and three HDMI 1.4 inputs.
But if Silicon Image’s new Sil9779 port processor can handle both formats, why bother with HDMI 2.0 in the first place, especially with its speed limitations? Wouldn’t it make more sense to future-proof all inputs and go with superMHL across the board? (Of course, the cost of adopting superMHL could weigh heavy on that decision.)
In the commercial AV and broadcast worlds, it would definitely make sense to jump to superMHL in the interests of future-proofing installations. Given the limited rollout of HDMI 2.0 to date, maybe supporting both HDMI 1.4 for legacy devices and superMHL is a smarter approach. (Note that superMHL and HDMI 2.0 both support HDCP 2.2, which is the next level in encryption and NOT compatible with older versions of HDMI.)
Summing up; the race for faster interface speed just got a lot more interesting with the addition of superMHL to the lineup. I can imagine that manufacturers of AV matrix switchers and distribution amplifiers are feeling another migraine headache coming on…
EDITOR’S NOTE: Last week, it was announced that Silicon Image has been acquired by Lattice Semiconductor of Hillsboro, Oregon, “ a leading provider of programmable connectivity solutions” according to the press release. The acquisition price was about $600M and now leaves Lattice in control of HDMI, MHL and superMHL, and SiBEAM (WiHD) patents and IP. More information can be found on the Lattice Web site at http://www.latticesemi.com/.
There’s fast…and then there’s FAST.
- Published on Friday, 26 September 2014 16:42
- Pete Putman
- 0 Comments
There’s Fast…and then There’s FAST.
A little over a year ago, Silicon Image announced the latest version of HDMI – 2.0. Among the other enhancements to this interface was an increase in the clock rate to 600 MHz, allowing data rates as high as 18 gigabits per second (GB/s).
Good thing, too, with Ultra HD televisions coming to market. The previous iteration of HDMI (v1.4) had a capped data rate of 10.2 Gb/s, which was barely fast enough for Ultra HD signals (3840×2160 pixels) refreshed at 30 Hz, with color depth not to exceed 8 bits per pixel.
By boosting the speed to 18 Gb/s, HDMI 2.0 can now pass a 60 Hz Quad HD signal – but only with 8-bit RGB color. (If you’re willing to cut the color resolution in half, you can increase the bit depth.) To me, that’s not enough of an improvement: If you’ve seen what it takes to shoot, edit, and post 4K content, you’ll realize why 10-bit and even 12-bit encoding is the way to go. But HDMI 2.0 can’t handle that with high frame rates.
Earlier this month, the Video Electronics Standards Association “officially” announced what we knew was coming for some time – DisplayPort version 1.3, which will boost its data rates to a mind-boggling 32 Gb/s – almost twice as fast as HDMI 2.0 – and also employ for the first time a form of visually-lossless compression, known as Display Stream.
Unlike HDMI, DisplayPort is a pure digital transport, using packet-based communication. It transports video, audio, metadata, and even Ethernet, using four scalable “lanes” to carry signals. In the current version (1.2), the capped data rate for each lane is 5.4 Gb/s, but with version 1.3, it will rise to 8 Gb/s.
DisplayPort’s architecture is designed to be flexible. There are full-sized and mobile versions of the connector, along with wireless and optical fiber interface specifications. Users of Apple MacBooks are familiar with the Mini DisplayPort interface, and a mobile version (Mobility DisplayPort or SlimPort) is available for tablets and phones and uses a single lane for 1080p/60 playback.
The maximum data rate for all four lanes is 21.6 Gb/s, which can accommodate a 3840x2160p/60 signal encoded with 10 bits per pixel in the RGB format. That’s considerably faster than HDMI 1.4 and one reason why a handful of TV manufacturers are adding DP 1.2 connectors to their new 4K TVs. The other reason is the lack of royalties (for now) to use the interface.
At CES, VESA announced DockPort, a multiplexed signal format that blends USB 3.0 connectivity with display signals in the standard and mini DP connectors. Now, there has been a major announcement by the USB 3.0 Promoter Group and the Video Electronics Standards Association (VESA) of something called “USB Type-C Alternate Mode.”
Drilling deeper, we find that the USB 3.0 Group has introduced a new variation of their interface, known as the Type-C connector. Unlike other versions (Types A&B and their more commonly used “full-size” and “mini” designations); the type-C connector borrows a page from Apple’s playbook and is reversible. That is; it makes no difference which way you plug it in – there is no right side or wrong side up.
There’s more: The Type-C connector (about half as large as a conventional USB Type-A connector) can carry serial data at speeds up to 10.2 Gb/s (USB 3.1 Gen 2). It can also deliver up to 100 watts of power (20 volts DC at a maximum of 5 amperes) so that a connected device could be operated while its battery charges.
There are 12 pins on a Type-C connector arrayed along both edges of the blade. Viewed from the end, the top and bottom pins are reversed from left to right, which is how you can plug it in either way and it will still work. Two pins (1 and 12) are used for ground. Pins 2 and 3 are reserved for a high-speed transmit (TX) data path, while pins 10 and 11 are reserved for a receive data (RX) path.
Pins 4 and 9 provide bus power, and pin 5 (CC) is used to communicate with the connected device to determine operating mode. Finally, pins 6 and 7 function as a USB 2.0 interface. Needless to say, the host and connected device need a USB 3.0-compatible connector switch to determine the operating mode and enable data exchange in 2.0 or 3.0 formats.
What’s unique about Type-C cables is that so-called “full feature” passive cables will actually contain an internal ID chip that signals the source connection to turn on all USB 3.0 functions and enable high-speed data exchange. These cables will be able to transmit 10.2 Gb/s of data over 1 meter (3 feet) and 5 Gb/s over 2 meters (6 feet).
Using Alternate DisplayPort mode, a maximum of four DP “lanes” of display data can travel over that same tiny USB connector, providing all the resolution and bit depth of the full-size and mini DisplayPort connectors. Or, you can reserve two lanes for USB 3.1 operation and employ the other two for displays, something you might want to do in a docking station application. USB 2.0 data exchange is always available through the same connector.
As you can see, the USB connector has gotten a lot smaller. It’s also a lot faster, and is symmetrical (no more fumbling around trying to orient the plug the right way). And it can provide the primary display connection for any device while also sending and receiving high-speed data.
With this announcement, the USB 3.0 Group and VESA have shown that “less is more” when it comes to digital signal interfacing with Type-C Alternate operation. Oh, did I mention that you will be able to buy and use a cable with a Type-C USB connector on one end and a DisplayPort plug on the other? Can’t get any easier to use than that!
CES 2014 In The Rear-View Mirror
- Published on Tuesday, 21 January 2014 15:21
- Pete Putman
- 0 Comments
Once again, CES has come and gone. It sneaks up on us right after a relaxing Christmas / New Year holiday. We’re jolted out of a quiet reverie and it’s back to the rush to board at the airport gate, walking the serpentine lines for taxis at McCarran Airport, and “late to bed, early to rise” as we scramble to make our booth and off-site appointments in Las Vegas.
We don’t make them all on time. Some we miss completely. But there’s a serendipity angle to it all: We might find, in our haste to get from one meeting to another, some amazing new gadget we didn’t know about as we take shortcuts through booths in the North, South, and Central Halls.
Or a colleague sends us a text or leaves a voicemail, emphatically stating “you have to see this!” Or a chance meeting leads to an ad hoc meeting, often off-site or over a hasty lunch in the convention center.
My point is this: You “find” as many cool things at the show as you “lose.” For every must-see product that you don’t see, there’s another one you trip over. Granted; many “must-see” products are yawners – you’ve figured it out 30 seconds into your carefully-staged meeting with PR people and company executives, and you’re getting fidgety.
My best CES discoveries involve products or demos where I can observe them anonymously, without PR folks hovering at my side or staring at my badge before they pounce like hungry mountain lions.
Unlike most of my colleagues in the consumer electronics press, I don’t need to break stories the instant I hear about them. There are already too many people doing that. What’s missing is the filter of analysis – some time spent to digest the significance of a press release, product demo, or concept demo.
And that’s what I enjoy the most: Waiting a few days – or even a week – after the show to think about what I saw and ultimately explain the significance of it all. What follows is my analysis of the 2014 International CES (as we are instructed to call it) and which products and demos I thought had real significance, as opposed to those which served no apparent purpose beyond generating daily headlines and “buzz.”
Curved TV screens: OK, I had to start with this one, since every TV manufacturer at the show (save Panasonic and Toshiba) exhibited one or more curved-screen OLED and LCD televisions. Is there something to the curved-screen concept? On first blush, you’d think so, given all of the PR hype that accompanied these products.
The truth is; really big TV screens do benefit a little from a curved surface, particularly if they are UHDTV models and you are sitting close to them. The effect is not unlike Cinerama movie screens from the 1950s and 1960s. (That’s how I saw Dr. Zhivago and 2001: A Space Odyssey back in the day.)
Bear in mind I’m talking about BIG screens here – in the range of 80 inches and up. The super-widescreen (21:9 aspect ratio) LCD TVs shown by Samsung, LG, and Toshiba used the curve to great effect. But conventional 16:9 TVs didn’t seem to benefit as much, especially in side-by-side demos.
The facts show that worldwide TV shipments and sales have declined for two straight years, except in China where they grew by double digits each year. TV prices are also collapsing – you can buy a first-tier 55-inch “smart” 1080p LCD TV now for $600, and 60-inch “smart” sets are well under $800 – so manufacturers will try anything to stimulate sales.
Is that the reason why we’re seeing so many UHDTV (4K) TVs all of a sudden? Partially. Unfortunately, there’s just no money in manufacturing and selling 2K TVs anymore (ask the Japanese manufacturers how that’s been working for them), and the incremental cost to crank out 4K LCD panels isn’t that much.
Chinese panel and TV manufacturers have already figured this out and are shifting production to 4K in large panels while simultaneously dropping prices. You can already buy a 50-inch 4K LCD TV from TCL for $999. Vizio, who is a contract buyer much like Apple, announced at the show that they’d have a 55-inch 4K LCD TV for $1299 and a 65-inch model for well under $2,000.
Consider that the going price for a 55-inch 4K “smart” LCD TV from Samsung, LG, and Sony is sitting at $2,999 as of this writing and you can see where the industry is heading. My prediction is that all LCD TV screens 60 inches or larger will use 4K panels exclusively within three years. (4K scaling engines work much better than you might think!)
And don’t make the popular mistake of conflating 4K with 3D as ‘failed’ technologies. The latter was basically doomed from the start: Who wants to wear glasses to watch television? Not many people I know. Unfortunately, glasses-free (autostereo) TV is still not ready for prime time, so 3D (for now) is basically a freebie add-on to certain models of televisions.
4K, on the other hand, has legs. And those legs will get stronger and faster as the new High Efficiency Video Codec (HEVC) chips start showing up in televisions and video encoders. HEVC, or H.265 encoding, can cut the required bit rate for 2K content delivery in half. That means it can also deliver 4K at the old 2K rates, somewhere in the ballpark of 10 – 20 Mb/s.
While consumer demand for 4K is slowly ramping up, there is plenty of interest in UHDTV from the commercial AV sector. And Panasonic focused in on that sector almost exclusively in their CES booth. I’m not sure why – there are plenty of inferences here; most significantly, it would appear that Panasonic is exiting the money-losing television business entirely. (Ditto nearby Toshiba, which had similar 4K “applications” showcased and which also did not exhibit a line of 2014 televisions.)
Long story short; you may be buying 4K televisions in the near future whether you want ‘em or not. It’s a manufacturing and plant utilization issue, and if commercial demand for 4K picks up as expected, that will drive the changeover even faster.
As for sources of 4K content; Samsung announced a partnership with Paramount and Fox to get it into the home via the M-Go platform. Comcast had an Xfinity demo for connected set-top-boxes to stream 4K, and of course Netflix plans to roll out 4K delivery this year direct to subscribers.
I’m not sure how they’ll pull that off. My broadband speeds vary widely, depending on time of day: I’m writing this at noontime and according to CNET’s Broadband Speed Test, my downstream bit rate is about 22 megabits per second (Mb/s). Yet, I’ve seen that drop to as low as 2 – 3 Mb/s during late evening hours, when many neighbors are no doubt streaming Netflix movies.
Even so, HEVC will definitely help that problem. I spoke to a couple of Comcast folks on my flights out to and back from CES, and they’re all focused on the bandwidth and bit rate challenges of 2K streaming, let alone 4K. More 4K streaming interface products are needed, such as Nanotech’s $300 Nuvola NP-H1, which is about the size of an Apple TV box and ridiculously simple to connect and operate.
Oh, yeah. I should have mentioned organic light-emitting diode (OLED) displays earlier. There were lots of OLED displays at CES, ranging from the cool, curved 6-inch OLED screen used in the new LG G-Flex curved smartphone to prototype 30-inch OLED TVs and workstation monitors in the TCL booth and on to the 55-inch, 65-iunch, and even 77-inch OLED TVs seen around the floor. (LG’s 77-inch offering is current the world’s largest OLED TV, and of course, it’s curved.)
OLEDs are tricky beasts to manufacture. Yields are usually on the low side (less than 25% per manufacturing run) and that number goes down as screen sizes increase, which explains the high prices for these TVs.
And there’s the unresolved issue of differential color aging, most notably in dark blue emitters. With current OLED science, you can expect dark blue emitters to reach half-brightness at about 5,000 hours of operation with a maximum brightness of 200 nits. Samsung addresses this quandary by employing two blue emitters for every red and green pixel on their OLED TVs, while LG has the more difficult task of managing blue aging in their white OLED emitters.
Several studies over the past three years consistently show people hanging on to their flat screen TVs for 5 to 7 years, which is likely to be a lot longer than 5,000 hours of operation. Will differential color aging rear its ugly head as early adopters shell out close to $10K for a 55-inch OLED TV? Bet on it.
Turns out, there’s another way to get wide color gamuts and saturated colors: Quantum dots. QDs, as we call them, are inorganic compounds that exhibit piezoelectric behavior when bombarded with photons. They emit stable, narrow-bandwidth colors with no drift, and can do so for long periods of time – long enough to work in a consumer television.
QDs are manufactured by numerous companies, most notably Nanosys and QD Vision in the United States. The former company has partnered with 3M to manufacture an optical film that goes on the backside of LCD panels, while the latter offers Color IQ optical components that interface with the entire LED illumination system in edge-lit TVs.
Sony is already selling 55-inch and 65-inch 4K LCD TVs using the Color IQ technology, and I can tell you that the difference in color is remarkable. Red – perhaps the most difficult color to reproduce accurately in any flat-screen TV – really looks like red when viewed with a QD backlight. And it’s possible to show many subtle shades of red with this technology.
All you need is a QD film or emitter with arrays of red and green dots, plus a backlight made up of blue LEDs. The blue passes through, while the blue photons “tickle” the red and green dots, causing them to emit their respective colors. It’s also possible to build a direct-illumination display out of quantum dots that would rival OLED TVs.
How about 4K display interfaces? By now, you’ve probably heard that HDMI has “upgraded” to version 2.0 and can support a maximum data rate of 18 gigabits per second (GB/s). Practically speaking; because of the way display data is transmitted, only 16 Gb/s of that is really available for a display connection. Still, that’s fast enough to show 4K content (3840×2160, or Quad HD) with a 60 Hz frame rate, using 8-bit color.
Over at the DisplayPort booth, I heard stories of version 1.3 looming later this spring. DisplayPort 1.2, unlike HDMI, uses a packet structure to stream display, audio, and other data across four scalable lanes, and has a maximum rate of 21.6 Gb/s – much faster than HDMI. Applying the “20 percent” rule, that leaves about 17.3 Gb/s to actually carry 4K signals. And the extra bits over HDMI means that DP can transport 3840×2160 video with a frame rate of 60 Hz, but with 10-bit color.
Don’t underestimate the value of higher data rates: 4K could turn out to be a revolutionary shift in the way we watch TV, adding much wide color gamuts, higher frame rates, and high dynamic range (HDR) to the equation. HDMI clearly isn’t fast enough to play on that field; DP barely is. Both interfaces still have a long way to go.
So – why not make a wireless 4K connection? There were plenty of demos of wireless connectivity at the show, and I’m not just talking about Wi-Fi. Perhaps the most impressive was in the Silicon Image meeting room, all the way at the back of the lower South Hall, near the Arizona border.
SI, which bought out wireless manufacturer SiBEAM a few years ago, demonstrated super-compact 60 GHz wireless HDMI and MHL links using their UltraGig silicon. A variety of prototype cradles for phones and tablets were available for the demo: Simply plug in your handheld device and start streaming 1080p/60 video to a nearby 55-inch LCD TV screen.
Granted, the 60 GHz tech is a bit exotic. But it works quite well in small rooms and can take advantage of signal multipath “bounces” by using multiple, steerable antenna arrays built-in to each chip. And it can handle 4K, too – as long as the bit rate doesn’t exceed the HDMI 2.0 specification, the resolution, color bit depth, and frame rate are irrelevant.
This sort of product is a “holy grail” item for meeting rooms and education. Indeed; I field numerous questions every year during my InfoComm wireless AV classes along these lines: “Where can I buy a wireless tablet dongle?” Patience, my friends. Patience…
The decline in TV shipments and sales seems to be offset by a boom in connected personal lifestyle and health gadgets, most notably wristbands that monitor your pulse and workouts. There were plenty of these trinkets at the show and an entire booth in the lower South Hall devoted to “digital health.”
Of course, the big name brands had these products – LG’s LifeBand was a good example. But so did the Chinese and Taiwanese manufacturers. “Digital health” was like tablets a few years back – so many products were introduced at the show that they went from “wow!” to “ho-hum” in one day.
This boom in personal connectivity extends to appliances, beds (Sleep Number had a model that can elevate the head of the bed automatically with a voice command), cars (BMW’s i3 connected electric car was ubiquitous), and even your home. Combine it with short-range Bluetooth or ZigBee wireless connectivity and you can control and monitor just about anything on your smartphone and tablet.
Granted; there isn’t the money in these small products like there used to be in televisions. But consumers do want to connect, monitor, and control everything in their lives, and their refrigerators, cars, beds, televisions, percolators, and toasters will be able to comply. (And in 4K resolution, too!)
Obviously, I didn’t visit the subjects of gesture and voice control. There were several good demos at the show of each, and two of the leading companies I showcased last year – Omek and Prime Sense – have been subsequently acquired by Intel and Apple. Hillcrest Labs, PointGrab, and other had compelling demos of gesture control in Las Vegas – a subject for a later time.
Summing up, let’s first revisit my mantra: Hardware is cheap, and anyone can make it. Televisions and optical disc media storage are clearly on the decline, while streaming, 4K, health monitoring, and wireless are hot. The television manufacturing business is slowly and inexorably moving to China as prices continue their free-fall.
The consumer is shifting his and her focus to all the devices in the home they use every days; not just television. Connectivity is everything, and the television is evolving from an entertainment device into a control center or “hub” of connectivity. The more those connections are made with wireless, the better – and that includes high-definition video from tablets and phones.
It’s going to be an interesting year…
HDMI 2.0 Is Here…And It’s Not Fast Enough?
- Published on Wednesday, 04 September 2013 15:51
- Pete Putman
- 0 Comments
This morning, the HDMI Forum announced the release of HDMI 2.0, which was almost two years in the making. The impetus for this new standard was and continues to be 4K, which requires such increases in data rates that the older 1.4 version can’t support it, except at slow frame rates.
Now, HDMI 2.0 has a maximum data rate of 18 gigabits per second (Gb/s), slightly faster than DisplayPort’s 17.2 Gb/s. If you do the math, this should be fast enough to transport 3840×2160 video with frame rates of 50 and 60 Hz, using 8-bit and 10-bit color (at 60 Hz, the clock rate for 8-bit 4K is about 14.9 Gb/s; with 10-bit color, about 17.9 Gb/s).
Here are the highlights from the official press release:
“HDMI 2.0, which is backwards compatible with earlier versions of the HDMI specifications, significantly increases bandwidth up to 18Gb/s and adds key enhancements to support continuing market requirements for enhancing the consumer video and audio experience. New functionality includes:
– Support for 4k@50/60, (2160p: 4 times the clarity of 1080p/60 video resolution)
– Up to 32 audio channels for a multi-dimensional immersive audio experience
– Up to 1536kHz audio sample frequency for the highest audio fidelity
– Simultaneous delivery of dual video streams to multiple users on the same screen
– Simultaneous delivery of multi-stream audio to multiple users (up to 4)
– Support for the wide-angle theatrical 21:9 video aspect ratio
– Dynamic synchronization of video and audio streams
– CEC extensions provides expanded command and control of consumer electronics devices through a single control point
HDMI 2.0 does not define new cables or new connectors. Current High Speed cables (Category 2 cables) are capable of carrying the increased bandwidth.”
After reviewing the specifications, it appears to me that the HDMI Forum was trying to squeeze every last drop of speed out of the existing connector/interface architecture without having to re-engineer the standard. There’s no mention of locking connectors (a bugaboo of the broadcast and AV industries). Nor is there any discussion of speeding up HDCP key exchanges beyond what’s already been accomplished with InstaPort. But an HDMI 2.0 standard should eliminate the need for two or even four separate HDMI ports to playback 4K content (several TV and projector manufacturers currently use this approach).
Adding multiple channels of audio and increasing the sampling frequency is relatively simple stuff, as the bit rates for audio are a small fraction of those needed for 2K and 4K video. And you can already deliver two separate video streams through one HDMI connector – it’s only a bandwidth issue; the new standard just establishes a protocol for doing so. Supporting 21:9 isn’t all that big a deal, either.
I’m not sure what “dynamic synchronization of video and audio streams” means yet and will have to talk to the folks at HDMI Licensing to get a better explanation. As for CEC, it appears that control functionality has been souped-up beyond the basic command sets used to operate AV receivers and Blu-ray players.
What’s clear now is that HDMI 2.0 is NOT going to be the big breakthrough many of us analysts and writers expected, and that it will NOT be able to transport 10-bit and 12-bit 4K video running at higher frame rates (>60 Hz). Both of these specifications are necessary to develop high dynamic range (HDR) video and movie content.
Nor is there any indication of supporting a high-speed data bus overlay like Thunderbolt, which is becoming more important with the growth in popularity of tablets and smart phones, not to mention ultrabooks. These devices are leading the industry changeover to single, dense, multifunction interfaces across all sorts of CE products.
In contrast; over at VESA, they’ve already commenced development of Display Stream, a new interface that will use “light” JPEG compression to push data rates up to 25 Gb/s and beyond over conventional DisplayPort connections. This is a more “future-proof” approach to display connectivity and reflects the current state of 4K and UHDTV product and content development, what with all of the 4K television announcements that have been made this year.
But the reality is that HDMI dominates the CE marketplace and is making major inroads to commercial AV and broadcast installations. The market has largely ignored DisplayPort, despite the facts that (a) there are currently no royalties associated with its use, (b) its connectors come in many different flavors, including support for mobile and fiber optic interfaces, and (c) it already supports a high-speed data bus overlay – the 20 Gb/s Thunderbolt layer.
Maybe they’ll get it right next time..
4K: HDTV Redux?
- Published on Tuesday, 20 November 2012 12:18
- Pete Putman
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4K acquisition and display was the topic of a panel discussion I participated in during last week’s CCW / SATCON show at the Javits Center in New York City. My fellow panelists were technology guru and veteran video engineer Mark Schubin, and Larry Thorpe, senior fellow at Canon’s Imaging Technologies Group, and we gave attendees some useful perspective on what may be the next “gold rush” for television manufacturers.
Schubin’s comments pertained to just how much detail the human eye can perceive, and how contrast is often more important than viewing distance and screen sizes. (Did you know the average viewer sits about nine feet away from a TV, which measures most often between 40 and 49 inches in diagonal screen size? So much for 42-inch 4K televisions…)
He went on to add that perhaps the greatest benefit of 4K digital film and video production would be higher quality 2K HDTV delivered to the home, as 4K imaging sensors can capture far more detail than native 2K sensors because they have 4x the number of photosites.
Thorpe talked about the challenges of designing lenses for 4K cameras and illustrated that there are no lenses for 4K cameras with equivalent zoom ratios to today’s 2K camera optics – not an insurmountable obstacle, but a challenge nonetheless for camera manufacturers.
He also provided details about a live 4K broadcast earlier this of a baseball game in Japan via satellite links, using a nominal data rate of 120 Mb/s, and discussed how Fox Sports has used a pair of 4K Sony F65 cameras this season to assist NFL referees when they review challenged plays.
My comments were focused on the availability of 4K projection and direct-view displays, the majority of which are very large screens that present logistical challenges in the average home. I also gave the audience an idea of the bit rates involved in moving 4K content at high frame rates from source to display (how does 6 Gb/s per color channel at 3840×2160/60Hz with 10-bit color grab you?) and why this will be a headache for current implementations of HDMI and DisplayPort.
At the 2012 SMPTE Fall Technical Conference last month in Hollywood, I chaired a session on UHDTV, and the three papers presented detailed an 8K camera/projection system developed by NHK; a compact, 25-megapixel 70mm (4K) Panavision camera with flash memory, and an update on SMPTE standards for transporting ever-greater amounts of data as we move to higher resolution imaging and workflows.
Interestingly, the last presentation, made by John Hudson of Semtech Corporation, showed quite clearly that copper isn’t quite dead yet when it comes to high data rates, and that reaching speed as high as 96 Gb/s is clearly possible over short lengths of coaxial cable. (To be sure; there’s still plenty of work for optical fiber interfaces in broadcast and film production environments.)
Hudson talked about the SMPTE 32NF40 Multi-Link 3G Ad Hoc Group that is currently working to standardize doubling and even quadrupling of 3G HD-SDI interfaces towards the goal of achieving 6 Gb/s and 12 Gb/s uncompressed data rates, suitable for 10-bit and 12-bit 4K production workflows. He also pointed out that telecom switches capable of handling 6, 12, and even 24 Gb/s data rates are readily accessible and not cost-prohibitive.
In the consumer world, Hisense made some news when it announced three new 4K (3840×2160) edge-lit LCD TVs would launch at CES 2013. This new line, known as the XT-880 series, will be available in 50-inch, 58-inch, and 65-inch screen sizes. All three models will support active shutter 3D, come with Internet access (built-in WiFi), and are equipped with an ARM dual-core microprocessor running on Android’s Ice Cream Sandwich OS. (They even support gesture recognition and voice control!) No retail prices have been announced yet.
At CES, we’re likely to see a larger 4K TV from Toshiba, who is apparently going to source the 84-inch IPS glass that LG Display is selling to LG and Sony. Not so JVC, who confirmed to me that they have no interest in selling their 84-inch version of the LGD glass (PS-840UD) to consumers, save for high-end home theater installations. It’s more of a general-purpose 4K monitor for professional work. And we know Samsung will put the spotlight on their 85-inch 4K PVA LCD TV, which was announced two weeks ago but has yet to make its appearance in any kind of an “official’ press release photo.
Finally, I was asked by a friend in the TV industry regarding rumors that we’d hear about an updated version of HDMI, to be announced in Las Vegas. This version, which will allegedly be v1.5, will supposedly address the data transfer speed limitations of HDMI (currently capped at 8 Gb/s with overhead and 10.2 Gb/s with all overhead removed). Presently, HDMI is hard-pressed to show 4K content at frame rates higher than 30 Hz, which requires about 2.5 Gb/s per color channel for a 3840×2160 video stream).
If you hadn’t heard, there is a group of manufacturers working with Silicon Image on a specification for HDMI 2.0, which is intended to address a whole host of problems with the currently interface – not the least of which is its speed limit. One motivator for the upgrade to 2.0 is clearly DisplayPort, a competitive digital display interface targeted at notebooks and ultrabooks and which, at 17.2 Gb/s, is clearly fast enough to carry a 4K signal at 60 Hz with 10-bit color (about 6 Gb/s per channel). So a short-term ‘jump’ to HDMI 1.5 seems more like a Band-Aid right now, but you never know what the marketing guys at the big TV brands are yelling for.
And speaking of DisplayPort, the Wireless Gigabit (WiGig) Alliance announced last Friday that it is now collaborating with the Video Electronics Standards Association (VESA) to define and refine a specification for 60 GHz wireless DisplayPort, using 2.6 GHz-wide channels available in many countries. So it’s entirely possible that we’ll be able to connect 4K displays without any cables at all by the time 4K content becomes widely available.
If you’ve spotted parallels between these developments and the early days of the transition to HDTV, you’re not alone. At present, there are (a) questions about what a “true” 4K resolution specification should be, (b) scarcities in cameras and production equipment, (c) bandwidth challenges to overcome, (d) high-priced displays that we know will become affordable quickly enough, and € competing interface standards.
The only thing missing is an optical disc format war, but with the Blu-ray format currently limited to 8-bit color, don’t be surprised if that conflagration breaks once again. Just like the good old days of HDTV…