ffmpeg-3.3 is now in tree.
# nvidia drivers are unmasked here
media-video/ffmpeg -nvenc
-# Ilya Tumaykin <itumaykin+gentoo@gmail.com> (19 Jan 2017)
-# Requires yet unavailable >=media-video/ffmpeg-3.3.
->=media-video/mpv-0.23.0 cuda
-
# Magnus Granberg <zorry@gentoo.org> (18 Jan 2017)
# masked in base, unmask for amd64
>=sys-devel/gcc-6.3.0 -pie
# cuda is not available on x86 nvidia-video-codec depends on it
media-video/libav nvidia
-# Ilya Tumaykin <itumaykin+gentoo@gmail.com> (19 Jan 2017)
-# Requires yet unavailable >=media-video/ffmpeg-3.3.
->=media-video/mpv-0.23.0 cuda
-
# Andreas Sturmlechner <asturm@gentoo.org> (31 Dec 2016)
# on behalf of Andreas K. Hüttel <dilfridge@gentoo.org> (14 Dec 2016)
# Fails to build with newly unmasked ffmpeg-3, so mask this useflag