Python / OpenCV轨道栏，＆＃34; AttributeError：＆＃39; NoneType＆＃39;对象没有属性＆＃39; rint＆＃39; ＆＃34;

Question

我最近开始使用HoughCirlces学习圆检测，并希望通过将参数转换为跟踪条来更深入地探索这些参数。一切运行正常，直到参数变得太大，我得到以下错误：

    Traceback (most recent call last):
      File "C:\Users\Benji\Documents\Python Scripts\HoughParameters.py", line 55, in <module>
        Circles()
       File "C:\Users\Benji\Documents\Python Scripts\HoughParameters.py", line 43, in Circles
        circles = np.uint16(np.around(circles))
      File "C:\Anaconda\lib\site-packages\numpy\core\fromnumeric.py", line 2621, in around
        return _wrapit(a, 'round', decimals, out)
       File "C:\Anaconda\lib\site-packages\numpy\core\fromnumeric.py", line 45, in _wrapit
        result = getattr(asarray(obj), method)(*args, **kwds)
    AttributeError: 'NoneType' object has no attribute 'rint'

轨道栏限制是根据HoughCircles可接受的设置来设置的，因此我猜测轨道栏的功能如何，我不太了解。代码如下：

    import cv2
    import video
    import sys
    import numpy as np


    def nothing(x):
        pass
    def Circles():
        cv2.namedWindow('Circles')
        cv2.namedWindow('parameters')

        cv2.createTrackbar('dp', 'parameters', 1, 20, nothing)
        cv2.createTrackbar('minDist', 'parameters', 10, 700, nothing)
        cv2.createTrackbar('CannyParam', 'parameters', 1, 300, nothing)
        cv2.createTrackbar('AccumulatorThrs', 'parameters', 1, 100, nothing)
        cv2.createTrackbar('minRadius', 'parameters', 1, 50, nothing)
        cv2.createTrackbar('maxRadius', 'parameters', 51, 700, nothing)


        image = cv2.imread('openCVlogo.png')
        gray = cv2.cvtColor(image, cv2.COLOR_BGR2HSV)
        gray = gray[:,:,2]
        #cv2.imshow('ImageGray', gray)
        while True:
            dp = cv2.getTrackbarPos('dp', 'parameters')
            minDist = cv2.getTrackbarPos('minDist', 'parameters')
            CannyParam = cv2.getTrackbarPos('CannyParam', 'parameters')
            AccumulatorThrs = cv2.getTrackbarPos('AccumulatorThrs', 'parameters')
            minRadius = cv2.getTrackbarPos('minRadius', 'parameters')
            maxRadius = cv2.getTrackbarPos('maxRadius', 'parameters')

            circles = cv2.HoughCircles(gray,cv2.cv.CV_HOUGH_GRADIENT,dp,minDist,CannyParam,AccumulatorThrs,minRadius,maxRadius)
            circles = np.uint16(np.around(circles))

            for i in circles[0,:]:
                cv2.circle(image,(i[0],i[1]),i[2],(0,255,0),2)
                cv2.circle(image,(i[0],i[1]),2,(0,0,255),3)

                cv2.imshow('Circles', image)

             if cv2.waitKey(1) & 0xFF == ord('q'):
                break
        cv2.destroyAllWindows()

    Circles()

我使用OpenCV logo作为测试图片。我上传了一个屏幕截图，但不幸的是这是我的第一篇文章，我不允许这样做。任何帮助将不胜感激！即使只是谷歌的一条跳跃之路。