alsa-lib : Advanced Linux Sound Architecture Library ( https://alsa-project.org/wiki/Main_Page )
libvpx : WebM VP8 and VP9 Codec SDK ( https://www.webmproject.org )
mesa : OpenGL-like graphic library for Linux ( https://www.mesa3d.org/ https://mesa.freedesktop.org/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a d-e-s-o
For Paludis use this rsync : rsync://gentoo.zugaina.org/d-e-s-o-portage
If you have a problem : ycarus(-at-)zugaina.org