OpenCV 如何从噪声和误报中清除轮廓

Question

我在 Python 中找到了带有标准函数 cv2.findContours 的图像轮廓。但是正如您所看到的，中间有一个点，我无法在不破坏轮廓线的情况下对其进行过滤。我怎样才能删除这样一个误报集群？轮廓之外的那些并不重要。    gray = cv2.cvtColor(self.img, cv2.COLOR_RGB2GRAY)    _, mask = cv2.threshold(gray, thresh=152, maxval=162, type=cv2.THRESH_BINARY)    self.mask = cv2.bitwise_and(gray, mask)    self.contours, hierarchy = cv2.findContours(self.mask, cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)

Answer 1

避免误报的一种好方法是考虑面积最大的轮廓：

import imutils #to use sorting functionality 

#To install imutils run: pip install imutils for python 2.x

#Run: pip3 install imutils for python 3.x

cnts = imutils.grab_contours(cnts) #where cnts is the variable in which contours are stored, replace it with your variable name

cnts = sorted(cnts, key = cv2.contourArea, reverse = True)[:10] #sorts contours according to their area from largest to smallest.

largestCont = cnts[0] #store the largest contour

这将删除小点，同时只给出最大的轮廓