Python图像处理之简单画板实现方法示例_Python

Python图像处理之简单画板实现方法示例

2021-03-30 00:37老司机的诗和远方 Python

这篇文章主要介绍了Python图像处理之简单画板实现方法,结合实例形式分析了Python基于cv2模块与numpy模块的数值计算及矩形图形绘制简单操作技巧,需要的朋友可以参考下

本文实例讲述了Python 图像处理之简单画板实现方法。分享给大家供大家参考，具体如下：

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()