def normalize_x_data(x_data):
    """
    This function will normalize the training and testing images.

    Parameters
    ----------
    x_data : ndarray
        The training and/or testing images.

    Returns
    -------
    numpy.ndarray
        A normalized training and/or testing image values.
    """
    max_value = 255.0
    x_data_normalized = x_data / max_value
    return x_data_normalized