def METHOD_NAME(self, image, xscale=(0, 1.), yscale=(0, 1.),
                       colormap=None):
    """Set a background image
    :param image: 2D image, array of shape (nrows, ncolumns)
        or (nrows, ncolumns, 3) or (nrows, ncolumns, 4) RGB(A) pixmap
    :param xscale: Factors for polynomial scaling  for x-axis,
        *(a, b)* such as :math:`x \mapsto a + bx`
    :param yscale: Factors for polynomial scaling  for y-axis
    """
    self._plot.addImage(image, legend=self._bgImageLegend,
                        origin=(xscale[0], yscale[0]),
                        scale=(xscale[1], yscale[1]),
                        z=0,
                        colormap=colormap)