def get_kp(frame,do,c,s):
    """
    Returns the keypoints for a single frame of video.

    Parameters
    ----------
    frame : numpy.ndarray
        The frame of video to be analysed.
    do : function
        Function provided by Hourglass code for inference.
    c : tuple of int
        The coordinates for the centre of the image.
    s : float
        The scale of the image such that height/scale = 200.

    Returns
    -------
    keypoints : numpy.ndarray
        The keypoints of the frame consisting of an x, y and confidence value 
        for each keypoint.
    """
    pred = do(frame,c,s);
    kps = pred[0]["keypoints"];
    return kps;