News

Boccaccio: Secretive HDMI 2.0 Posture is B.S.

HDMI folks are quiet on the new transmission method of version 2.0. Posture is B.S., according to Jeff Boccaccio.


HDMI 2.0 transmission: why so quiet?
Jeff Boccaccio · December 5, 2013

Needless to say, the features and benefits that HDMI Rev. 2.0 offers will make long distance transmission even more of a challenge to the skilled CE professional, but there is reportedly a secretive new transmission method that will soon alleviate fears dealers might have about the ability to send 4K x 2K @60Hz frame rate.

Let me explain. First, let’s face it… the big driving force behind this new revision is the ability to provide higher quality 4K x 2K. This includes both the current 3840 x 2160 pixels as well as 4096 x 2160 pixels.

In order to provide these resolutions there are several frame support methods:

First, there is an ability to transport lower 4K x 2K 10-bit resolution video with a channel data rate of 3.4Gb/s @24Hz frame and color sampling of 4:2:2. By reducing the frame rate to 24 frames per second, about half what we have been using under 1080p @ 60Hz, it allows for this 4K format to operate under Rev 1.4 and a 340MHz clock.

Second, there’s a new 4K format under Rev. 2.0 that still supports a low 4K x 2K resolution; however, this one is a bit different. Instead of using a 24Hz frame rate it supports the 60Hz frame rate that has been in high demand. However, the color sampling was reduced from the 4:2:2 to a color sampling of 4:2:0 and a color depth of only 8 bits versus 10. Now every other pixel row gets one of the two colors at a time. The advantage here is that it provides the 60Hz frame rate while operating with a TMDS clock of 300MHz. This allows it to operate under a Rev. 1.4 environment and bandwidth of 3.4Gb/s per channel. This is all “Good Ju Ju” for sure.

Third, the new Rev. 2.0 transmits Full 4K x 2K resolution at a 60Hz frame rate with deep color supported. Only catch here is that the TMDS clock skyrockets from 300MHz to 600MHz at a data rate equal to 6Gb/s per channel.

It’s that third scenario above that has everyone nervous. Integrators can imagine what it could mean to their normal installation routines to move 6Gb/s (18Gb/s Aggregate) through all those cables and electronics that are already struggling to handle 3.4Gb/s. So does that mean we need a new cable specification? And if we did, what would that specification even look like?

Well, a new spec is not on the horizon because, first, even if anyone decided to build such a cable it would probably be as big as a moose, and second, it would probably cost a bloody fortune.

That being said, the HDMI Forum has reportedly found a way to use existing HDMI High Speed Cable products (300MHz) under the new Rev. 2.0. This is all great news except for the fact that the Forum has not publicly announced what this new transmission method is. Some industry leaders are calling it “hocus-pocus.” No matter what they call it, all Forum members are being told to keep this method of transmission under wraps.

Why So Secretive?

I have no clue why the Forum is being so secretive and quite frankly I believe it is a bunch of B.S. and a ridiculous posture to take. But it is what it is.

Since DPL is part of a prestigious Test and Measurements Service community there is a huge amount of resources available to tap into to discover what many of these mysteries are about, with “hocus-pocus” being one of them. But out of respect for the HDMI Forum, we will only release data when appropriate and/or needed in our general industrial demographic.

So how does all this relate to you and your business? While it would be nice to say that the “hocus–pocus” is really cool, it still does not mean there will not be any pitfalls. One serious pitfall unfortunately will still be the marketing people. They will still be out there providing you with those ever-so-famous talking points that mean absolutely nothing. In fact, in most cases, they are just flat out wrong. So you can only imagine what it will be like with all this new mumbo jumbo trickling out into the cosmic space of the custom integrator.

Another pitfall will be when applying long distance applications. Due to the complexity of the “hocus pocus,” extenders may not function correctly with this new transmission method. Now don’t go out there kicking and screaming that HDMI sucks. They have nothing to do with those extenders except to provide them with the specification. It is the extender manufacturer that is responsible for keeping an eye out for changes to the interface and provides the means to carry on.



Secure Your Free Pass to CEDIA EXPO 2019

Register before Sept. 2 to gain free access to the opening keynote, product training & education series as well as the show floor including Innovation Alley and much more. Don’t miss your chance. Sign up today.




  About the Author

Jeff Boccaccio is president of DPL Labs. Jeff can be reached at info@dpllabs.com. Have a suggestion or a topic you want to read more about? Email Jeff at jeff@dpllabs.com

Follow Jeff on social media:

Jeff also participates in these groups:
LinkedIn · Google+

View Jeff Boccaccio's complete profile.



  Article Topics


News · All Topics
CE Pro Magazine

Read More Articles Like This… With A Free Subscription

CE Pro magazine is the resource you need to keep up-to-date on the latest products, techniques, designs and business practices. Subscribe today!

Subscribe Today!