NHK Describes 8K Capture at 240 Hz
One of the critical needs for any sports broadcast today is a slow-motion instant replay. This feature is a must-have for 8K to become a mainstream capture solution, said Rob Willox, Director of Marketing at Sony Electronics, in a recent 8K Monitor article. Answering the call is NHK which has shown a camera capable of 8K capture at 240 Hz to support slow-motion replay.
According to a paper published by NHK, the Japanese broadcaster that has led the global development of the 8K ecosystem, you need a high frame rate camera and a recorder to capture those images in real-time.
The 8K high-speed camera is equipped with a 1.25-inch 33-megapixel high-speed image sensor developed by NHK. This sensor can shoot at speeds of 240 frames per second, four times the 60 frames per second that of most 8K cameras. A unique technology simultaneously processes signals in parallel.
The amount of 8K video data captured is equivalent to 230 high-definition cameras. NHK also developed a technology for bundling multiple signals and transmitting them at high speed to send this large amount of video data to the recorder without delay. By incorporating technology that compresses and records video at high speed in the recorder, the system can record 240 frames per second continuously for up to 4 hours and simultaneously performs slow-motion playback.

This solution is not new as it has already been used in many BS8K programs, including high profile events like the 2018 FIFA World Cup Russia Tournament, the Rugby World Cup 2019 Japan Tournament, and the 2020 Tokyo Olympics.

NHK’s Atsuhiro Hirao, the Chief Producer of 8K Olympics and Paralympics, did not disclose any details of their signal processing or compression slicing technology. However, it seems likely that the solution is quite complex and a bit of a “brute force” approach. Since its initial development, advancements in processing, codecs, and interfaces mean that a solution developed today can be much more commercially viable. Hirao-san could not disclose if they have plans for an upgraded camera or if a commercial company plans to develop an offering. It is a piece of the ecosystem that will be needed, but timing and cost will play a significant factor in any commercialization plans.