Python图像处理实现画板

Python图像处理实现画板：

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 cv2 import numpy as np # null function def nothing(x):     pass Drawing = False Mode = True IX,IY = -1,-1 def 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 chanels         Img = np.zeros((660,660,3),np.uint8) #create window cv2.namedWindow('Image') #create track bar, range for 0~255 cv2.createTrackbar('R','Image',0,255,nothing) cv2.createTrackbar('G','Image',0,255,nothing) cv2.createTrackbar('B','Image',0,255,nothing) #set mouse ack  cv2.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 sources cv2.destroyAllWindows()

最后的效果图如下