def median_depth_img(self, num_img=1, fill_depth=0.0):
        """Collect a series of depth images and return the median of the set.

        Parameters
        ----------
        num_img : int
            The number of consecutive frames to process.

        Returns
        -------
        DepthImage
            The median DepthImage collected from the frames.
        """
        depths = []

        for _ in range(num_img):
            _, depth, _ = self.frames()
            depths.append(depth)

        median_depth = Image.median_images(depths)
        median_depth.data[median_depth.data == 0.0] = fill_depth
        return median_depth