This article has been originally published at www.display-central.com.
Both Technicolor and THX have introduced and demonstrated 4K certification systems for consumer television. At first glance, you might think these certifications are addressing the same issues and are therefore competitive. However, interviews with the THX and Technicolor development teams , as reported in my previous two posts, revealed just the opposite.
THX’s approach will be the most familiar to people in the display and TV communities. Their approach is to certify that the TV set displays the 2K and 4K signals as faithfully as possible, so that the creator’s intent is realized. To do this, they apply high standards for black-and-white uniformity, off-axis consistency, light leakage, motion artifacts, jaggies, and blotchiness (which display people would call mura). When testing reveals deficiencies, they can usually be corrected by modifying the set’s software, although hardware improvements are occasionally required.
Most non-THX-certified TV sets would probably not pass the THX requirements for motion artifacts and jaggies, said THX Senior Systems Engineer Jon Cielo. Cielo added, “It’s difficult to make a TV work as precisely as we would like it to.”
Upconverted 4K content looks very good on Sharp’s THX-certified 70-inch 4K TV, which indicates how important a highly specified display and TV is to image quality.
Technicolor’s self-appointed mission could not be more different. Technicolor does not look at the TV set at all. Instead, they have developed a series of algorithms that produces an upconverted 4K image that is perceptually very close to a native 4K image. The Technicolor process first removes noise from the original 2K signal because one effect of upconversion, which synthesizes 3 pixels for every 1 pixel in the original signal, is to magnify the effect of noise. The additional pixels are then synthesized and inserted, and the algorithms restore texture, including film grain. Additional algorithms perform line sharpening and remove of jaggies.
A lot of tuning of the algorithms has to be done because processing that works well for some images on some backgrounds creates artifacts in others. In the end, the algorithms are tested on a wide variety of 2K images, which are compared to native 4K images.
Tests with groups of viewers “are surprisingly reliable in sorting out the algorithms. Our algorithms come in very close to [native 4K images],” said Kirk Barker, Senior VP of Development and Strategy in the Technology Licensing Division of Technicolor Thomson and VP of Technology Licensing at Technicolor. Technicolor 4K Certification assures that products embodying the algorithms implement them correctly.
The first product to receive this certification is the VTV-122X family of video processing chips from Marseille Networks. A side-by-side demonstration of Marseille-upconverted 2K vs. 4K this June produced images that were indistinguishable from a few feet away. The first consumer product is the Toshiba BDX 6400 media box and Blue-ray player, which contains a Marseille chip.
To sum up, THX certifies the TV set. Technicolor focuses on the image itself. “We look at the HDMI output from the Blu-ray Disk player,” says Technicolor’s Barker. “Once you hook it up the TV set and you get into set issues. We don’t get into that layer.”
So there is no competition here. Indeed, the ideal up-converting 4K system would incorporate both certifications: Technicolor for signal; THX for the set. -Ken Werner