Python图像处理也是依赖opencv的Python接口实现的，Python语言简单易懂，简洁明了。本次实现画板涂鸦，一个是在里面画矩形，还有画线。其他也都可以扩展，本案例只做例程，思路是对鼠标事件的处理，以及滚动条调节颜色处理。鼠标事件就包含有左键按下，以及释放事件的处理。
import cv2import numpy as np# null functiondef nothing(x): passDrawing = FalseMode = TrueIX,IY = -1,-1def drawCircle(Event,X,Y,Flags,Param): R = cv2.getTrackbarPos('R','Image') G = cv2.getTrackbarPos('G','Image') B = cv2.getTrackbarPos('B','Image')#get color value Color = (B,G,R); global IX,IY,Drawing,Mode if Event == cv2.EVENT_LBUTTONDOWN: Drawing = True IX,IY = X,Y elif Event == cv2.EVENT_MOUSEMOVE and Flags == cv2.EVENT_FLAG_LBUTTON: if Drawing == True: if Mode == True: cv2.rectangle(Img,(IX,IY),(X,Y),Color,-1) else: cv2.circle(Img,(X,Y),3,Color,-1); elif Event == cv2.EVENT_LBUTTONUP: Drawing = False#create image with 3 chanelsImg = np.zeros((660,660,3),np.uint8)#create windowcv2.namedWindow('Image')#create track bar, range for 0~255cv2.createTrackbar('R','Image',0,255,nothing)cv2.createTrackbar('G','Image',0,255,nothing)cv2.createTrackbar('B','Image',0,255,nothing)#set mouse ackcv2.setMouseCallback('Image',drawCircle)while(1): cv2.imshow('Image',Img) k = cv2.waitKey(10)&0xFF #switch draw mode if k == ord('m'): Mode = not Mode elif k == 27: break#you must destroy all of sourcescv2.destroyAllWindows() 
