TrueConf has announced full support for 4K point-to-point video calls in 3840×2160 resolution. Ultra HD video calls are available in TrueConf 7.2 application for Windows.
To run video calls in Ultra HD quality, both participants need to use 6th generation Intel Core i7+ processor-based PC, a 4K webcam, an Ultra HD monitor and a high-speed network connection (8 Mbps in both directions). If these system requirements are met, the client application will automatically switch to 4K resolution (3840 × 2160 at 30 fps).
For more details, go here.