'cmap is a colors.Colormap instance
norm is a colors.Normalize instance to map luminance to 0-1
kwargs are an optional list of Artist keyword args'

def __init__(self, fig, cmap=None, norm=None, offsetx=0, offsety=0, origin=None, **kwargs):

    super(FigureImage, self).__init__(None, norm=norm, cmap=cmap, origin=origin)
    self.figure = fig
    self.ox = offsetx
    self.oy = offsety
    self.update(kwargs)
    self.magnification = 1.0
