When I tried to display wmv file with Japanese file name from javafx.scene.media.MediaView,
following exception are displayed and can not play it.

FX Media Object caught Exception com.sun.media.jmc.MedaUnsupportedException: Unsupported media: file:///C:/Users/root/Documents/[Japanese file name].wmv
     source ='file:///C:/Users/root/Documents/[Japanese file name].wmv
                                        :
                                        :

BTW, Japanese file name can use javafx.scene.image.Image, like:

    url: "file:///C:/Users/root/Documents/[Japanese file name].jpg"

So, please also change to be able to use Multi-byte file name on javafx.scene.media.Media.