HDMI Gets Nod as Interface for 3DTV

The Consumer Electronics Association has started standards work aimed at enabling home systems to play stereoscopic 3-D video. The group's first step will be to upgrade the interconnect standard at the heart of the High Definition Multimedia Interface (HDMI) to make sure it is ready to carry stereo 3-D data.

The move marks the first major step for hardware makers toward defining 3DTV standards. The Society of Motion Picture and Television Engineers kicked off in August an effort to explore setting standards for 3DTV mastering formats, and a number of ad hoc industry groups have formed around the concept of stereo 3-D TV.

Hollywood studios want to enable a home market for the increasing number of stereo 3-D titles they are creating. However, many sources note the underlying technology for stereo 3-D is still in its infancy. The CEA convened an exploratory meeting to discuss 3DTV at its annual forum in Las Vegas on October 22.

"It was one of our bigger meetings there," said Brian Markwalter, vice president of technology and standards at CEA. "We tend to have about 50 people in video-related meetings, but this topic drew more than 60 people and included much more participation from content companies than usual," he said.

The meeting included presentations on the display technology behind 3DTV and an update on the SMPTE effort. A speaker from the 3D@Home consortium also gave a talk on stereo 3-D. Attendees came away convinced there's both a market need and viable technology for 3DTV products, Markwalter said. He noted that Samsung and Mitsubishi are shipping 3-D-ready flat-panel TV's based on digital light processing technology from Texas Instruments.

"The evidence is 3-D movies bring in more revenue than 2-D ones so far, but these days a good deal of the revenue for movies is not from theaters but from downstream sales in pre-recorded media and video-on-demand," said Markwalter. "It looks very promising, especially since some companies are shipping products, so it's clear the technology is there," he said.

CEA will form a task force under its video systems committee to identify what 3DTV standards it needs to set for consumer electronic devices. The exploratory group suggested a number of areas for potential efforts, chief among them an upgrade of the CEA 861 standard that defines an uncompressed video interconnect at the heart of HDMI.

"The working group behind that standard has to look at 3-D transport issues," something it now has been chartered to do, said Markwalter.

The interface could be key because studios want to create one master file that can carry stereo 3-D and perhaps 2-D content across all the various distribution schemes including cable TV, satellite, over the air, packaged media and the Web.

"It all has to come to some common point and in the near term that is almost certainly an HDMI interface," said Markwalter. "As long as we can find at least one way the 3-D data can move across that interface so systems can render it, we start moving toward creating that 3-D marketplace," he said.

The decision comes at a time when one studio executive called for a standard 3DTV interface. Alan Bell, chief technology officer of Paramount Studios said today's 3DTV products are immature and need a way to be forward compatible with better systems that will emerge in the future.

Silicon Image, the company that originally developed the HDMI interface, has been tracking industry discussions about 3DTV. It has not started any active development in the area, said Lew Paceley, marketing director for digital TV and home theater products at the company.

"The HDMI version 1.3 standard provides enough link performance to allow left and right eye image transfers at 1080-progressive resolution and 60 Hz refresh rates," Paceley said. "You might need to add some data to say this is not a regular video stream, but the raw performance is there," he added.

The CEA group also discussed the possibility of creating standards for 3DTV active and passive eyeglasses, metadata, on-screen displays and user controls. It is also considering whether it needs to articulate common terms for stereo 3-D technologies.

By Rick Merritt, EE Times