python---opencv常用函数

求点的最小外接矩

 rect1 = cv2.minAreaRect(box):

 

def back_forward_convert(coordinate, with_label=True):
    """
    :param coordinate: format [x1, y1, x2, y2, x3, y3, x4, y4, (label)] 
    :param with_label: default True
    :return: format [x_c, y_c, w, h, theta, (label)]
    """

    boxes = []
    if with_label:
        for rect in coordinate:
            box = np.int0(rect[:-1])
            box = box.reshape([4, 2])
            rect1 = cv2.minAreaRect(box)

            x, y, w, h, theta = rect1[0][0], rect1[0][1], rect1[1][0], rect1[1][1], rect1[2]
            boxes.append([x, y, w, h, theta, rect[-1]])

    else:
        for rect in coordinate:
            box = np.int0(rect)
            box = box.reshape([4, 2])
            rect1 = cv2.minAreaRect(box)

            x, y, w, h, theta = rect1[0][0], rect1[0][1], rect1[1][0], rect1[1][1], rect1[2]
            boxes.append([x, y, w, h, theta])

    return np.array(boxes, dtype=np.float32)