The highest video resolution supported by the EOS 1D X Mark II is 4096 x 2160 pixels. That's 7% more video resolution than a 3840 x 2160 pixels digital camera, which is the most common video resolution supported by comparable spec digital cameras that have been on the market for around the same time as the EOS 1D X Mark II. In addition, this camera supports a video resolution of 1920 x 1080 pixels.
This camera's video resolution (4096 x 2160 pixels) is in fact the best supported video resolution across all similar spec cameras that have been around for around the same time as the EOS 1D X Mark II.
A 320 x 120 pixels video resolution is the worst supported video resolution amongst comparable types of camera.