The BBC is to screen Doctor Who's Christmas special in 4K resolution and high dynamic range (HDR) colour via iPlayer. When the programme is broadcast, viewers will be prompted to switch to the higher quality streamed version by pressing the red button.
US video platforms including Disney+, Netflix, Apple TV+ and Amazon Prime Video commonly offer content in this format. But it is more rare on the BBC and Sky.
To take advantage of the facility, households will need a compatible TV and a relatively fast internet connection.
