It is also not final yet, so require -strict experimental.
Requires a bump to version 17.
61a3449 libx265: Add 4:2:2 support
configure | 4 ++--
libavcodec/libx265.c | 12 +++++++++---
2 files changed, 11 insertions(+), 5 deletions(-)
Upstream: git.libav.org