[MPlayer-users] Do I need cross compile some decoder when I cross compile mplayer?

I cross compiled mplayer to run it on arm board. But failed on playing. I think maybe I need cross compile some decoders. Do I need cross compile some decoders when I cross compile mplayer? Does mplayer contains the common decoders in its source code? And how to use them? need I copy the decoders to arm board before mplayer running? Maybe my question is too simple. But I really need your help. Thanks very much.