Media Player is Being Updated Today to Support 4K Video on PS4 Pro
Starting sometime later today, the Media Player app on PS4 Pro is getting an update that will add support for 4K video playback. This means, following this update, 4K videos in mp4 format saved on a USB Stick or home server can be played on the Media Player app.
According to John Koller
For those of you who own PlayStation VR in addition to PS4 Pro, Media Player will also now support playback of 4K VR video content. PS VR’s display resolution is 1920 X RGB X 1080, so 4K VR videos will be displayed in a higher image quality compared to HD VR videos. Koller also points out/reminds everyone that 4K streaming is also (and has been) supported, and includes 4K support across apps like Netflix, YouTube, and Hulu.