def composeVideoMaskName(maskprefix, starttime, suffix):
    """
    :param maskprefix:
    :param starttime:
    :param suffix:
    :return: A mask file name using the provided components
    """
    if maskprefix.endswith('_mask_' + str(starttime)):
        return maskprefix + '.' + suffix
    return maskprefix + '_mask_' + str(starttime) + '.' + suffix