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Digital Video Pain – You Are Not Alone by Christopher Maione

Months ago I wrote about the analog sunset and migration to digital video signals, and how we are leaving a world of composite and component video and moving to the digital world of DVI, HDMI and HDCP compliance. (See my blog at http://www.avtechnologyonline.com/blogArticle.aspx?id=43210)
This migration is being led by the movie industry in efforts to thwart piracy and ensure copyright protection. In the very basic sense, when you play a Blu-Ray DVD it sends out a “key” to the display (flat panel or video projector) and is looking for a “handshake” confirming the key has been accepted. In the simple world of connecting a DVD player or Cable / Satellite box to TV this is pretty straightforward. Carry this concept over to the commercial audiovisual world and the challenges bestowed upon the AV systems designers is enough to make you want to jump off a building.

  • Sure, there are first generation solutions such as Crestron DigitalMedia but this only solves part of the challenge. Sometimes. Being able to route the digital signal (along with an authenticated key) is only part of battle. Signal type (DVI, SDI, HDMI) and resolution (720p, 1080i, 1080p, and every PC resolution) must also “match” inputs and outputs in order for the signal to be properly routed and displayed.

So it’s fairly simple to route a Blue-Ray DVD to a flat panel or video projector because for the most part these devices cooperate and authenticate the key of HDCP handshake. The problem we face and the painful part comes from the multitude of other commercial AV equipment which (at present) will not play nice and pass or authenticate the HDCP handshake. Included in the list of equipment which is not HDCP-compliant are:· CODEC’s
· Video production switchers
· Scalers / Transcoders
· Control room QC video monitors
· Fiber transcoders

To add another facet to the problem, most HDMI, HDCP-compliant devices want to work ONLY with standard HD resolutions of 720p and 1020p. Devices utilizing HDMI connections do not typically deal with standard PC resolutions such as 1024 x 768 and the multitude of higher resolutions (enough to drive you crazy, right?)

Companies such as AJA, Gefen, and TV One each make a wide variety of signaler converters / transcoders. Just review the input and output resolutions of these products before inserting them into a system design. If you do not “match” devices properly in digital format resolution, expect to stare at a bunch of blank screens or images which are skewed.

Also be wary...at present, specifications indicate (which is no guarantee in this dynamic changing environment) compliance with HDMI 1.3. However version 1.4 is knocking at the door. Even the folks at Crestron are scratching their heads daily trying to keep up with the multitude of equipment and how HDMI / HDCP signals are routed. Signal capabilities and resolution in/out of a device are usually different via the HDMI port versus the DVI port – more confusion!

Want to route a Blue Ray DVD player to a CODEC? Good luck. Want to send a video record feed to the input side of a HDCP compliant DVR? Good luck again. Want to route an HDMI signal in a control room through a video production switcher, a mixing console, preview audio and video locally and then send a smooth transition wipe of the Blu-Ray mixed with a PC signal to a 103-inch flat panel and a DVR for recording? LOL!

So, you are not alone. We are all in the same digital transition mess. There isn’t an AV professional out there who isn’t challenged on a current project with some painful form of the digital migration turmoil. In a way, it’s good for our industry as this separates the AV professionals from the trunk slammers. Unfortunately, as this new technology evolves we may all feel like jumping off a few buildings in the process. I know that’s what it came to for me last week:

http://www.youtube.com/watch?v=hkIGJGWiPvI

Christopher Maione, CTS-D, is president of Christopher Maione Associates, a firm specializing in all aspects of AV business, technologies, emerging trends, and marketing strategy. Reach him at cmaione@chrismaione.com
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