HDMI: Take It or Leave It
In case you hadn't noticed lately, there's been a big change in the connector panel of your new projectors, monitors, and video interfaces. Along with the usual composite, S-video, component, and 15-pin VGA jacks, you're more likely to find an HDMI connector these days than a DVI connector.
What about DisplayPort? The original DisplayPort 1.1 specification was released last year by the Video Electronics Standards Association (VESA) and is slowly winding its way through the display electronics world. As of this writing, only a few products have incorporated DisplayPort connectors and I have yet to see it show up on a commercial AV interface.
The nice thing about DisplayPort is that it was designed by consensus, and as a result is likely to catch on quickly in desktop and notebook computing. That means we should eventually see monitors and projectors that incorporate DisplayPort.
One big advantage DisplayPort has over HDMI is its support for direct-drive monitor (DDM) designs, which are display panels that eliminate lots of internal video processing electronics. In theory, this could simplify monitor design considerably, not to mention cut down on weight and cost. The panel is simply driven directly from the computer's video card or from a server (take note, digital signage designers!).
Of course, there's an interoperability issue. On March 12, VESA issued an Interoperability Guideline for DisplayPort cable adapters, aimed primarily at you-know-who. To quote from the press release, "There is industry interest in establishing a means for achieving interoperability between DisplayPort Devices and DVI 1.0/HDMI-compatible devices. For example, it is desirable to have the ability to connect a cable between a DisplayPort source device and a DVI 1.0/HDMI sink device (or vice versa) and have the devices interoperate. This cannot currently be accomplished at the specification level, but can be accomplished at the product level."
Well, good luck with that. I'm sure you're familiar with the list of "big lies," such as "The check is in the mail." "Simple interface" has been used so many times for marrying HDMI and DisplayPort signals that it might be a candidate for the list.
Long story short, we're stuck with HDMI. So learn to live with it, and make sure any video signal distribution devices in your system are EDID-friendly. And maybe if we're lucky, someone will design a true, professional HDMI connector. Cross your fingers.
Pete Putman is a Pro AV contributing editor and president of ROAM Consulting in Doylestown, Pa.