4:2:2 and 4:4:4 support in the HEVC standard was approved in
October 2014 as part of HEVC Version 2 and published in
January 2015:

http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=12296
http://www.itu.int/rec/T-REC-H.265-201410-S
https://hevc.hhi.fraunhofer.de/rextReviewed-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>