Ultra HD is more than just 4 times the resolution, as it also offers the opportunity for greater color depth, so explains Steven Corda, Vice President of Business Development North America for SES. Providing a bit of a pre-NAB Show tutorial at the 2017 ACA Summit, Corda explains in the above video some of the things, beyond an increase in pixels, that make 4k video stand out compared to traditional, high-definition 1080 or 720 resolution video:
- support of higher frame-rates, reducing blur in high-motion videos, such as sports programming
- deeper pixel depth (10 bit, instead of 8-bit), which eliminates banding in areas where there are color transitions (good illustration of that can be found in this image at 4k,com)
- a wider color gamut (making the colors more “true-to-life”)
- higher dynamic range (brighter brights and darker darks)
Corda briefly discusses the coding methods – HDR-10, Dolby Vision and Hybrid Log Gamma (HLG) – for transmitting the information about the higher dynamic range, so the television set can properly interpret the information about the pixels¹. Corda indicates that HLG, spearheaded by the BBC and NHK, is the focus of the broadcast and cable/IPTV industries for the distribution of content from camera to post-production to distribution to the TV.¹
Thanks to the wonders of compression improvement via the HEVC (h.265) codec, Corda indicates that the compressed video only needs 18 Mb/s of bandwidth, which is exactly the same as what HD required when it launched.
As of February 28th, 2017, SES has 15 U.S operators trialing their service and Corda indicates that some of these operators are gearing up for commercial launch. Although a set-top is not necessarily needed for televisions with QAM receivers fed by RF networks, Corda believes that set-tops will be the dominant way of decoding the signals and that 2017 is the year that IPTV and CATV operators will begin rolling out 4k set-tops.
Corda’s tutorial sparked an important question for this author, in his investigation of the Panasonic GH-5 as a possible new video camera for capturing ViodiTV content. That is, does the GH-5 support HLG? And the answer is…… almost, as, according to this review from Pocket-lint, the GH-5 will support HLG via firmware upgrades. So look out BBC or NHK, ViodiTV may soon be UHD broadcast ready!
ACA Summit coverage brought to you by the ACA and ViodiTV.