Yuji Nagata from NHK gave a presentation describing an 8K HDR broadcast workflow based on HLG. While trial broadcast of 8K content started in August of 2017 in Japan, this will expand to regular programming for 8 hours per day in December of 2018. The main broadcast will continue to be HD however, so an efficient method to capture at 8K and create 8K, 4K and 2K versions is needed.
Nagata’s presentation mainly focused on two hardware platforms. The 8K/4K color gamut/dynamic range (CG/DR) converter that was used is capable of converting between both HDR/Rec. 2020 and SDR/Rec. 709, and HLG and PQ. It is not capable of converting resolution and uses linear matrix processing for color gamut conversion.
The 8K/4K/2K Down converter is capable of converting from 8K and 4K images with HDR/Rec. 2020 to 2K images with SDR/Rec. 709. Color gamut conversion is processed using a 3D-LUT, so that the equipment can also be used to broadcast directly.
Table 3 from their paper describes the uses cases for these two pieces of gear. – CC