update image on panel, as quickly as possible

def update_image(self, data):
        """
        update image on panel, as quickly as possible
        """
        if 1 in data.shape:
            data = data.squeeze()
        if self.conf.contrast_level is not None:
            clevels = [self.conf.contrast_level, 100.0-self.conf.contrast_level]
            imin, imax = np.percentile(data, clevels)
            data = np.clip((data - imin)/(imax - imin + 1.e-8), 0, 1)
        self.axes.images[0].set_data(data)
        self.canvas.draw()