廢話不多說，直接上程式碼吧！

# -*- coding: utf-8 -*-
import cv2
import numpy as np
 
# -----------------------滑鼠操作相關------------------------------------------
lsPointsChoose = []
tpPointsChoose = []
pointsCount = 0
count = 0
pointsMax = 10
def on_mouse(event,x,y,flags,param):
 global img,point1,point2,count,pointsMax
 global lsPointsChoose,tpPointsChoose # 存入選擇的點
 global pointsCount # 對滑鼠按下的點計數
 global img2,ROI_bymouse_flag
 img2 = img.copy() # 此行程式碼保證每次都重新再原圖畫 避免畫多了
 
 # -----------------------------------------------------------
 # count=count+1
 # print("callback_count",count)
 # --------------------------------------------------------------
 
 if event == cv2.EVENT_LBUTTONDOWN: # 左鍵點選
  pointsCount = pointsCount + 1
  # 感覺這裡沒有用？2018年8月25日20:06:42
  # 為了儲存繪製的區域，畫的點稍晚清零
  # if (pointsCount == pointsMax + 1):
  #  pointsCount = 0
  #  tpPointsChoose = []
  print('pointsCount:',pointsCount)
  point1 = (x,y)
  print (x,y)
  # 畫出點選的點
  cv2.circle(img2,10,(0,255,0),2)
 
  # 將選取的點儲存到list列表裡
  lsPointsChoose.append([x,y]) # 用於轉化為darry 提取多邊形ROI
  tpPointsChoose.append((x,y)) # 用於畫點
  # ----------------------------------------------------------------------
  # 將滑鼠選的點用直線連起來
  print(len(tpPointsChoose))
  for i in range(len(tpPointsChoose) - 1):
   print('i',i)
   cv2.line(img2,tpPointsChoose[i],tpPointsChoose[i + 1],255),2)
  # ----------------------------------------------------------------------
  # ----------點選到pointMax時可以提取去繪圖----------------
  if (pointsCount == pointsMax):
   # -----------繪製感興趣區域-----------
   ROI_byMouse()
   ROI_bymouse_flag = 1
   lsPointsChoose = []
 
  cv2.imshow('src',img2)
 # -------------------------右鍵按下清除軌跡-----------------------------
 if event == cv2.EVENT_RBUTTONDOWN: # 右鍵點選
  print("right-mouse")
  pointsCount = 0
  tpPointsChoose = []
  lsPointsChoose = []
  print(len(tpPointsChoose))
  for i in range(len(tpPointsChoose) - 1):
   print('i',2)
  cv2.imshow('src',img2)
 
def ROI_byMouse():
 global src,ROI,ROI_flag,mask2
 mask = np.zeros(img.shape,np.uint8)
 pts = np.array([lsPointsChoose],np.int32) # pts是多邊形的頂點列表（頂點集）
 pts = pts.reshape((-1,1,2))
 # 這裡 reshape 的第一個引數為-1,表明這一維的長度是根據後面的維度的計算出來的。
 # OpenCV中需要先將多邊形的頂點座標變成頂點數×1×2維的矩陣，再來繪製
 
 # --------------畫多邊形---------------------
 mask = cv2.polylines(mask,[pts],True,(255,255))
 ##-------------填充多邊形---------------------
 mask2 = cv2.fillPoly(mask,255))
 cv2.imshow('mask',mask2)
 cv2.imwrite('mask.jpg',mask2)
 ROI = cv2.bitwise_and(mask2,img)
 #cv2.imwrite('ROI.bmp',ROI)
 #cv2.imshow('ROI',ROI)
 
 
# -----------------------定點ROI繪製，程式中未使用-------------------
def fixed_ROI():
 mask = np.zeros(img.shape,np.uint8)
 pts = np.array([[x1,y1],[x2,y2],[x3,y3],[x4,y4]],np.int32) # 頂點集
 pts = pts.reshape((-1,2))
 mask = cv2.polylines(mask,255))
 mask2 = cv2.fillPoly(mask,mask2)
 # cv2.imwrite('mask.bmp',mask2)
 # cv2.drawContours(mask,points,-1,-1)
 ROI = cv2.bitwise_and(mask2,img)
 cv2.imshow('ROI',ROI)
 # cv2.imwrite('ROI.bmp',ROI)
 
 
img = cv2.imread('yuantu.jpg')
# ---------------------------------------------------------
# --影象預處理，設定其大小
# height,width = img.shape[:2]
# size = (int(width * 0.3),int(height * 0.3))
# img = cv2.resize(img,size,interpolation=cv2.INTER_AREA)
# ------------------------------------------------------------
ROI = img.copy()
cv2.namedWindow('src')
cv2.setMouseCallback('src',on_mouse)
cv2.imshow('src',img)
cv2.waitKey(0)

以上這篇python3+opencv生成不規則黑白mask例項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。