The libX11-devel package contains libraries and header files for libX11.
acquired package info from repodata DB: repodata/69e709f4d2852d98f12867a74015d19384fe2727ff670fd70178cdde80b1e77e-primary.sqlite.bz2
XvMC is an extension of the X video extension (Xv) for the X Window System. The XvMC API allows video programs to offload portions of the video decoding process to the GPU video-hardware.
development files and header files for libXext
The libXext-devel package contains libraries and header files for developing applications that use libXext.