Windows 10 supports a royalty-free video coding format AV1
Through the Microsoft Store, Microsoft announced the introduction of support for the new AV1 patent-free video decoding for the Windows 10 system. AOMedia Video 1 (AV1 for short) is an open, patent-free video encoding format designed for streaming over a network. It was developed by the Open Media Alliance (AOMedia), which was founded in 2015 by semiconductor companies, video on demand providers and web browser developers.
AV1 is a frequency conversion format that uses traditional block-based coding but also incorporates new technologies. The encoding technology used in AV1 is mainly derived from Google’s VP9 next-generation video compression format VP10 but also included by Xiph.Org. The foundation’s main sponsor, Mozilla, developed the Daala video compression format and the video encoding technology used in the Thor video compression format developed by Cisco.
You can get AV1 Video Extension here.