使用python进行多边形识别

Question

我有代码可以识别点并从中构建多边形

def load_annoataion(p):
    '''
    load annotation from the text file
    :param p:
    :return:
    '''
    text_polys = []
    text_tags = []
    if not os.path.exists(p):
        return np.array(text_polys, dtype=np.float32)
    with open(p, 'r') as f:
        reader = csv.reader(f)
        for line in reader:
            label = line[-1]
            # strip BOM. \ufeff for python3,  \xef\xbb\bf for python2
            line = [i.strip('\ufeff').strip('\xef\xbb\xbf') for i in line]

            x1, y1, x2, y2, x3, y3, x4, y4 = list(map(float, line[:8]))
            text_polys.append([[x1, y1], [x2, y2], [x3, y3], [x4, y4]])
            if label == '*' or label == '###':
                text_tags.append(True)
            else:
                text_tags.append(False)
        return np.array(text_polys, dtype=np.float32), np.array(text_tags, dtype=np.bool)


def polygon_area(poly):
    '''
    compute area of a polygon
    :param poly:
    :return:
    '''
    edge = [
        (poly[1][0] - poly[0][0]) * (poly[1][1] + poly[0][1]),
        (poly[2][0] - poly[1][0]) * (poly[2][1] + poly[1][1]),
        (poly[3][0] - poly[2][0]) * (poly[3][1] + poly[2][1]),
        (poly[0][0] - poly[3][0]) * (poly[0][1] + poly[3][1])
    ]
    return np.sum(edge)/2.


def check_and_validate_polys(polys, tags, xxx_todo_changeme):
    '''
    check so that the text poly is in the same direction,
    and also filter some invalid polygons
    :param polys:
    :param tags:
    :return:
    '''
    (h, w) = xxx_todo_changeme
    if polys.shape[0] == 0:
        return polys
    polys[:, :, 0] = np.clip(polys[:, :, 0], 0, w-1)
    polys[:, :, 1] = np.clip(polys[:, :, 1], 0, h-1)

    validated_polys = []
    validated_tags = []
    for poly, tag in zip(polys, tags):
        p_area = polygon_area(poly)
        if abs(p_area) < 1:
            # print poly
            print('invalid poly')
            continue
        if p_area > 0:
            print('poly in wrong direction')
            poly = poly[(0, 3, 2, 1), :]
        validated_polys.append(poly)
        validated_tags.append(tag)
    return np.array(validated_polys), np.array(validated_tags)

我遇到此代码的问题，多边形沿Y轴定向为

X1，Y1，X2，Y2，X3，Y3，X4，Y4

34,64,43,64,43,79,34,79

34,132,43,132,43,148,34,148

34,200,43,200,43,216,34,216

34,268,43,268,43,285,34,285

34,337,43,337,43,353,34,353

34,405,43,405,43,421,34,421

这张图片可能会提供更好的理解

如何修改验证方程以接受多边形沿Y轴方向