演算法中，初始種子可自動選擇（通過不同的劃分可以得到不同的種子，可按照自己需要改進演算法），圖分別為原圖（自己畫了兩筆為了分割成不同區域）、灰度圖直方圖、初始種子圖、區域生長結果圖。

另外，不管時初始種子選擇還是區域生長，閾值選擇很重要。

import cv2
import numpy as np
import matplotlib.pyplot as plt

#初始種子選擇
def originalSeed(gray,th):
 ret,thresh = cv2.cv2.threshold(gray,th,255,cv2.THRESH_BINARY)#二值圖，種子區域(不同劃分可獲得不同種子)
 kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE,(3,3))#3×3結構元

 thresh_copy = thresh.copy() #複製thresh_A到thresh_copy
 thresh_B = np.zeros(gray.shape,np.uint8) #thresh_B大小與A相同，畫素值為0

 seeds = [ ] #為了記錄種子座標

 #迴圈，直到thresh_copy中的畫素值全部為0
 while thresh_copy.any():

  Xa_copy,Ya_copy = np.where(thresh_copy > 0) #thresh_A_copy中值為255的畫素的座標
  thresh_B[Xa_copy[0],Ya_copy[0]] = 255 #選取第一個點，並將thresh_B中對應畫素值改為255

  #連通分量演算法，先對thresh_B進行膨脹，再和thresh執行and操作（取交集）
  for i in range(200):
   dilation_B = cv2.dilate(thresh_B,kernel,iterations=1)
   thresh_B = cv2.bitwise_and(thresh,dilation_B)

  #取thresh_B值為255的畫素座標，並將thresh_copy中對應座標畫素值變為0
  Xb,Yb = np.where(thresh_B > 0)
  thresh_copy[Xb,Yb] = 0

  #迴圈，在thresh_B中只有一個畫素點時停止
  while str(thresh_B.tolist()).count("255") > 1:
   thresh_B = cv2.erode(thresh_B,iterations=1) #腐蝕操作

  X_seed,Y_seed = np.where(thresh_B > 0) #取處種子座標
  if X_seed.size > 0 and Y_seed.size > 0:
   seeds.append((X_seed[0],Y_seed[0]))#將種子座標寫入seeds
  thresh_B[Xb,Yb] = 0 #將thresh_B畫素值置零
 return seeds

#區域生長
def regionGrow(gray,seeds,thresh,p):
 seedMark = np.zeros(gray.shape)
 #八鄰域
 if p == 8:
  connection = [(-1,-1),(-1,0),1),(0,(1,-1)]
 elif p == 4:
  connection = [(-1,-1)]

 #seeds內無元素時候生長停止
 while len(seeds) != 0:
  #棧頂元素出棧
  pt = seeds.pop(0)
  for i in range(p):
   tmpX = pt[0] + connection[i][0]
   tmpY = pt[1] + connection[i][1]

   #檢測邊界點
   if tmpX < 0 or tmpY < 0 or tmpX >= gray.shape[0] or tmpY >= gray.shape[1]:
    continue

   if abs(int(gray[tmpX,tmpY]) - int(gray[pt])) < thresh and seedMark[tmpX,tmpY] == 0:
    seedMark[tmpX,tmpY] = 255
    seeds.append((tmpX,tmpY))
 return seedMark


path = "_rg.jpg"
img = cv2.imread(path)
gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
#hist = cv2.calcHist([gray],[0],None,[256],[0,256])#直方圖

seeds = originalSeed(gray,th=253)
seedMark = regionGrow(gray,thresh=3,p=8)

#plt.plot(hist)
#plt.xlim([0,256])
#plt.show()
cv2.imshow("seedMark",seedMark)
cv2.waitKey(0)

以上這篇關於初始種子自動選取的區域生長例項（python+opencv)就是小編分享給大家的全部內容了，希望能給大家一個參考，也希望大家多多支援我們。