python 获取，缩放和绘制轮廓的中心

Posted 2021-05-09

    
  def get_cnt_center(img, c):    # image img and contour c    
    M = cv2.moments(c)
    # cX, cY of center
    cX = int(M["m10"] / M["m00"]) 
    cY = int(M["m01"] / M["m00"])
    # draw the contour and center of the shape on the image
    cv2.drawContours(img, [c], -1, (0, 255, 0), 2)
    cv2.circle(img, (cX, cY), 7, (255, 255, 255), -1)
    cv2.putText(img, "center", (cX - 20, cY - 20),
    cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 255, 255), 2)
    plt.imshow(img)
    return (cX, cY)
                
                
                
                
  def scale_cnt_from_center(c, rate):
    M = cv2.moments(c)
    # cX, cY of center
    cX = int(M["m10"] / M["m00"]) 
    cY = int(M["m01"] / M["m00"])
    return ((c- [cX, cY])* rate + [cX, cY]).astype('int32')