3-D TV: The EE Times guide to the shifting landscape

"Optical media has the best scenario, then its cable and satellite and probably last is terrestrial because the challenges just get harder for them," said Wendy Aylsworth, vice president of engineering for SMPTE and a chief technologist for Warner Brothers studios.

Getting fitted for glasses

Due in part to the multiple formats for optical disks and broadcasts, the first sets may require users to select what kind of 3-D content they want to watch.

"Someday sets will automatically detect stereo 3-D formats, but for today users still have to choose the right one from an on-screen menu," said Phil Lelyveld, a 3-D program manager at the Entertainment Technology Center, a branch of the University of Southern California's School of Cinematic Arts.

"That's not something you want in the consumer marketplace," he said, adding that USC is showing TV makers technology it has developed to automate the process.

Likewise, CableLabs has found a way to take the 3-D control codes from HDMI 1.4 and make them available to the many HDMI 1.2 and 1.3 version set tops now in consumers' homes. The group also helped convince the HDMI Licensing LLC to relax its specs, in part to allow for the workaround.

CableLabs is calling for TV makers to take part in interoperability tests in its 3-D labs to make sure the first systems work smoothly. "HDMI is very powerful but it has so many options that if people don't implement them in the same way it won't work well," Broberg said.

Like the broadcasters, TV makers are adopting different display and glasses technologies to show stereo 3-D. Thus, for example, glasses used on a Toshiba set may not work for a Samsung TV. Vendors such as Panasonic will brand their glasses for the first-generation products to avoid confusion and flaunt what they claim is proprietary technology.

All the top vendors at CES showed prototype systems using active shutter glasses which are said to be the best solution for rendering a full 1,080p signal for both eyes. The cheaper passive polarized glasses used in theaters only deliver 540 horizontal pixels per frame, although some TV makers may use them for lower cost sets or for use in public places like sports bars.

"We have to deliver [source video] to both types of glasses, and we want to treat each equally and fairly," said Broberg of CableLabs. "There are advantages to each," he said.

It's not clear what display technologies TV makers are using or where they get it. However the vast majority of active shutter glasses at CES carried the RealD logo.

Like it or not, users will need glasses of some kind to view high def content, at least for the next decade. Researchers say it could require displays with four times today's resolution to deliver without visible artifacts high def stereo 3-D that can be seen by the naked eye.

Content producers say the situation is even worse on their end. It will require at least eight lenses per camera, and perhaps dozens, to properly capture video that can be seen in 3-D without glasses.

Technicolor showed a demo of so-called auto-stereoscopic 3-D TV at CES using its interpolation algorithm. However, it had a relatively narrow viewing area of ten degrees so users saw blurring when they moved their heads.

"It could require 8K resolution screens to do it well, so this could be 10-15 years away," said Thierry Borel, a researcher at Technicolor working on the project.

The good news is, users in the CEA survey showed a tolerance for glasses. About a third said they found 3-D glasses annoying before the saw a 3-D movie, but afterwards only 20 percent said the glasses were annoying.

3-D interfaces and conversion

Standards groups are playing catch up with the industry on 3-D. The CEA has started an effort to define a standard for the infrared signaling to active shutter glasses. However it is not expected to be finished until after first products ship. Greer of RealD said his company is not participating in the effort.

For its part the Digital Video Broadcasting Project in Europe is just starting to explore standards for stereo 3-D TV. The first meeting of a DVB group to set market requirements for the technology will be held Jan. 26.

David Daniels, a senior technologist at BskyB, said a parallel group looking into technical requirements is also just getting set up. It is expected to explore several areas including formats for source video, signaling over HDMI and codecs such as MVC.

"We're still in the early days of understanding how H.264 works," he said, noting the BBC recently reported it has achieved a new low bit-rate capability with the MPEG-4.

The DVB will also take up the hot issue of how to show graphics and subtitles in stereo 3-D space.

"If you want to check out how a 3-D TV vendor handles 2-D graphics, just hit the menu button on one of their demos," said Hays of Sony. "Some people treat it very elegantly, and others make your head explode," he said.