Final HDMI 2.1 specifications released with 8K, 10K and dynamic HDR support
While 4K displays are just starting to become the norm, the HDMI Forum is looking to the future with the release of the HDMI 2.1 specifications. The 8K@60 Hz resolution will probably not see much love in the next few years, but it is prominently supported by the 2.1 specifications. Current displays, however, get support for 4K@120 Hz, essentially doubling the refresh rate supported in the previous version. Other new features include dynamic HDR metadata, enhanced audio return channel, variable refresh rate, quick media switching, quick frame transport, auto low latency mode, and display stream compression.
The HDMI 2.1 standard also supports 10K resolutions for PC displays, digital signage, surveillance and various commercial and industrial AV solutions. The 10K support is possible since this resolution is not really a true multiple of the original 1080p standard. For reference, the 8K resolution can fit the resolution of exactly 4 x 4 1080p displays, but the 10K resolution can fit 5.3 x 4 1080p displays, so it only extends the width of the image, not both the width and the height as the 8K standard. The same is true for the 4K standard versus the 5K standard. The 8K and 10K resolutions can run at 120 Hz, as well, but only when the display stream compression technology is active.
In order to benefit from all these new features, users will need to buy new “Ultra High Speed HDMI” cables, since the current ones do not have the necessary 48 Gbps throughput. However, these new cables will be backward compatible with the previous standards, so they will work on older devices that do not support HDMI 2.1. No word on the pricing of these cable for now.