If my memory don't faults, libhybris are needed only xbmc. If you want to use mplayer the are not necessary.
On my A20 img mplayer play smooth 1080 without libhybris (using libvdpau), and xbmc play 1080 with libhybris.
Melanrz, which player are you developing?
libhybris is always needed when you want to use android binary on linux distribution, which is based on GNU lib C library. libvpdau supports only a few codecs in comparison of CedarX or android based libraries.
