def ratioTest(kps1, kps2, matches):
    """
    Take in two sets of keypoints and the set of matches between them
    Perform ratio test to get best matches (60% threshold)
    Return surviving matches
    """
    ratioMatches = list()
    for match in matches:
        m1, m2 = match
        if m1.distance < 0.60*m2.distance:
            ratioMatches.append(m1)
    return ratioMatches