The Numbers Game

The European Broadcast Union (EBU) sent mixed signals last week during IBC 2004, when it released findings calling for European broadcasters to get behind one HDTV standard: 720-line progressive at 50 frames per second (720p/50). The problem: There isn't a lot of 720p equipment around, says Peter MacAvock, executive director of the DVB (Digital Video Broadcast) office.

The report was submitted to the DVB as a recommendation, but sparks flew when fans of the 1080i format (and sellers of 1080i equipment) worried that the EBU's report was the final word on the matter. (Ironically, EBU had canvassed vendors at the show prior to the announcement to ensure 720 support.)

As a result, Phil Laven, director of the EBU's technical department, publicly stated at IBC that the EBU had not endorsed the report, despite tests showing that viewers favored 720.

The goal of the tests was to see if viewers noticed any significant difference between 720-line progressive or 1080-line interlace. Watching on 36- to 50-inch TV sets, viewers deemed the 720p format the best choice for these sizes. It offered greater bandwidth efficiency, and the extra resolution of 1080i wasn't required, since the sets weren't large enough to need the additional resolution.

The monitors were all 720p native. Even if the signal was 1080i, it would be converted to 720p for viewing. "We realize the natural preference for progressive displays," says Laven, "and we'll be making more detailed recommendations later."

Says BBC Director of Technology Peter Weitzel, "You really can't tell the difference unless the screen is larger than 50 inches."

One of Laven's colleagues, Sony's John Ive, made it clear where Sony stands. "720p will be a detour, not a migration," he said, citing the International Telecommunications Union's (ITU) endorsement of 1080i as the industry's common image format. Japanese broadcasters have selected 1080i as well.

For Tim Shepard, Tanberg director of strategic development, the 720p displays make that format the logical choice: "1080i isn't needed in that case." Thomson Grass Valley will need to develop more products to accommodate 720p/50, according to Jeff Rosica, vice president of strategic marketing and technology, but the French-based manufacturer believes the decision is a good one. "We'll be looking to integrate 720p/50 across our product line as quickly as possible," he adds.

There is another option emerging, though a currently unrealistic one: 1080-line progressive. The processing power required for 1080p is too intense for encoders and decoders, Shepard notes. Also, most manufacturers haven't spent R&D dollars working on 1080p gear unless it's acquisition gear for shooting major films on video at 1080p/24 frames per second.

One manufacturer, Panasonic, says it will have 1080p HD gear for its P2 format by 2008. Says DVB's MacAvock: "1080p is great, but it's overkill for a set under 50-inches."