Draft: screencastService: Add Gstreamer pipelines for AV1 encoding
AV1/libaom is used for videochat these days and as of Gstreamer 1.22 has
support for a realtime
profile.
Thus let's use it if a recent version of av1enc
(with support for the
usage-profile
property) is available.
Prefer the .webm
container format instead of .mp4
or .mkv
as it's
apparently best supported in practice and doesn't have license issues.
Draft until some further testing was done. Also additional property tweaking may be needed, especially for slow devices.