cv2.convexityDefects错误

Question

我在使用convexityDevects时遇到问题。我收到错误：AttributeError: 'module' object has no attribute convexityDefects

你有效地使用了这个命令吗？

#! /usr/bin/env python

import cv2
import numpy as np

img = cv2.imread('star.jpg')
img_gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
ret, thresh = cv2.threshold(img_gray, 127, 255,0)
contours,hierarchy = cv2.findContours(thresh,2,1)
cnt = contours[0]

hull = cv2.convexHull(cnt,returnPoints = False)
defects = cv2.convexityDefects(cnt,hull)
cv2.imshow('img',img)
cv2.waitKey(0)

cv2.destroyAllWindows()

Answer 1

Ubuntu 12.04附带过时的OpenCV 2.3.1-7（http://packages.ubuntu.com/precise/python-opencv），cv2.convexityDefects自OpenCV 2.4起可用。

您可以改用cv.ConvexityDefects。来自official docs：

  

cv.ConvexityDefects（contour，convexhull，storage）→convexityDefects      参数：

   contour – Input contour.
   convexhull – Convex hull obtained using ConvexHull2() that should contain
                pointers or indices to the contour points, not the hull points
                themselves (the returnPoints parameter in ConvexHull2() should
                be zero).
   storage – Container for the output sequence of convexity defects.
             If it is NULL, the contour or hull (in that order)
             storage is used.

     

该函数找到输入轮廓的所有凸性缺陷并返回一个序列   CvConvexityDefect结构，其中CvConvexityDetect定义为：