Stunning new image tech could be the killer app for next-generation TV - with or without Ultra HD
The Ultra-High-Definition 4K TV train is leaving the station, so to speak, and woe to any content provider or TV maker who isn’t on board.
Griffis is a longtime proponent for “better pixels” as opposed to “more pixels,” meaning brighter images with more colors. And in December, at Dolby’s offices in Burbank, Griffis and Dolby offered up a tech demonstration of a new imaging technology that showed the impact “better pixels” can have, delivering a “wow” factor not even early UHD TVs can match. The company plans to unveil the name for the new tech next week at CES, where it will have its first public showing.
“We’re not trying to rain on the 4K parade,” says Griffis. “But what we want to see is that for every pixel we want to see, we want them better.”
“This may be the icing that makes the UHD cake work.”
The Dolby demo, showing a 1080p HD picture with pumped-up brightness and color, was a startling improvement over even the best TVs available today, including the early UHD models. Metallic surfaces gleam like mirrors. Colors glow, luminous and rich. Highlights and shadows alike keep their detail. What’s more, unlike 4K TV, that improvement is visible even at a distance from the screen.
It’s as striking and impressive a difference as the difference between standard-definition and HD video. If you see it, you’ll want one for your living room. Now.
High Dynamic Range imaging, which makes the highlights brighter and the shadows darker, has long been considered low-hanging fruit by technologists in the digital imaging field. Many have long wondered why Hollywood and the camera and TV makers haven’t embraced it sooner, as they watched money flow into adding more pixels (standard-def to HDTV, 2K to 4K in cinemas), higher frame rates and 3D. Ultra HD will include some improvement in Dynamic Range, but those improvements haven’t fully arrived in the early models, and Dolby’s technology is even more ambitious than UHD.
A little background on brightness: The unit for luminance, or photons per unit of area, is “nits.” TV technicians talk about nits, cinema technicians use other units; Dolby is hoping everyone will settle on nits and have a common language.
Full noonday sun is around 1.6 billion nits. Moonlight is around 0.01 nits. Starlight is 0.0001 nits. That dynamic range is far, far greater than anything that televisions, device displays or movie theaters can reproduce. Moreover, it’s far greater than anything televisions or movie projectors even try to reproduce.
The limitations on TV and cinema dynamic range come from technologies that are barely used anymore: film projectors and cathode-ray-tube televisions. Color CRT picture tubes could get up to around 100 nits, so that’s what TV programs are color-graded for. Today’s flatscreen TVs, however, are generally capable of 300-500 nits, and at least one model reaches 1,000 nits. “(Televisions) have that headroom because they know light sells,” says Griffis. “The consumer guys have already eclipsed by five times or more (the brightness from) the studios, who are still living in the world of the 100-nit color grade.”
Screen brightness and color go hand in hand. With images so dim compared to the real world, there are great swaths of the visible color spectrum that no TV can reproduce, especially lighter shades.
Dolby demonstrated a (still officially unnamed) technology consumers would never see directly: A way of encoding a picture with a dynamic range that goes from from zero nits, i.e. total blackness, to 10,000 nits. That’s 100 times the peak brightness of a standard TV image today, and far more than any consumer TV today can deliver. In fact, to demonstrate their system, Dolby had to build a custom monitor that can pump out 4,000 nits. (The company has no plans, it says, to turn its prototype monitor into a consumer product.)
“It’s no secret that within Hollywood many folks have been somewhat ho-hum about the value of 4K over 2K,” says Griffis. He is careful not to criticize the impending 4K wave that is about to sweep over the entertainment landscape, saying “We love all our pixels equally,” but he is an evangelist for better pixels, not just more pixels.
“The incremental cost to do this is much less than the incremental cost to do 4K,” he points out. “Having better pixels actually costs less than having more pixels.”
Today’s digital cinema cameras like the Sony F65, Arri Alexa and RED cameras already can record the kind of dynamic range Dolby wants to deliver to consumers, but producers and studios have to compress it and color grade it for existing standards. Much of the dynamic range information is lost along the way. Dolby is hoping to create a future-proofed container for image information, big enough that studios can return to it as display technology improves.
The International Telecommunications Union’s recently adopted standards for UHD TV include improvements in color and dynamic range. However Dolby’s HDR technology goes beyond the ITU standards, so if the kind of dynamic range Dolby is arguing for is to be incorporated in the new TVs, the standard must be adjusted. Griffis says the U.S. administration has brought that argument to the International Telecommunications Union in Geneva, with support from Dolby.
The light sources for TVs will have to get much more energy efficient, however, before HDR televisions arrives in living rooms. California’s energy consumption standards wouldn’t permit a commercial version of Dolby’s 4,000-nit monitor, much less a 10,000-nit TV.
Also, in the short term, Griffis admits there is bound to be a chicken-and-egg problem: Existing content doesn’t deliver HDR, so there’s no pressure to make HDR televisions. And if no TVs can show HDR content, there’s no pressure to produce in HDR.
“People who realize this is truly disruptive and this is where more bang for the buck is, are starting to mobilize,” says Griffis. “Both the chickens and the eggs are starting to wake up.”
In cinemas, movie brightness is supposed to be around 48 nits (14 foot Lamberts, to use the measurement common among cinema technicians), which is about as bright as a film projected at 24 frames a second could be before the human eye would notice flickering. But the world’s cinemas have already mostly abandoned film. Digital cinema projectors are easily capable of overcoming the flicker of 24 fps, and new laser engines for projectors promise to make much more light available for cinema projection. At the same time, there have been arguments for brighter movie images, not least for 3D. Doug Trumbull’s proposed “Hypercinema” system would be brighter, with more dynamic range, than what’s in cinemas today.
Asked whether the kind of super-bright HDR images he’s talking about could be brought to cinemas, Griffis responded with a cryptic “Maybe,” suggesting more news on that topic is soon to come. Unlike TV, though, the addition of that much more brightness to cinemas could have major knock-on effects. It could be a highly disruptive technology.
“So was the iPhone when it came out,” says Griffis. “It changed the rules of the game. So, yeah.”