open-cv library is installed as cv2 in python

import cv2 library into this program

import cv2

import numpy library as np

import numpy as np

read an image using imread() function of cv2

we have to pass only the path of the image

img = cv2.imread(r’C:\Users\lw\Desktop\ppt\chengliuxiang.jpg’)

displaying the image using imshow() function of cv2

In this : 1st argument is name of the frame

2nd argument is the image matrix

cv2.imshow(‘original image’, img)

shape attribute of an image matrix gives the dimensions

row, col, plane = img.shape

here image is of class ‘uint8’, the range of values

that each colour component can have is [0 - 255]

create a zero matrix of order same as

original image matrix order of same dimension

temp = np.zeros((row, col, plane), np.uint8)

store blue plane contents or data of image matrix

to the corresponding plane(blue) of temp matrix

temp[:, :, 0] = img[:, :, 0]

displaying the Blue plane image

cv2.imshow(‘Blue plane image’, temp)
cv2.waitKey(0)

again take a zero matrix of image matrix shape

temp = np.zeros((row, col, plane), np.uint8)

store green plane contents or data of image matrix

to the corresponding plane(green) of temp matrix

temp[:, :, 1] = img[:, :, 1]

displaying the Green plane image

cv2.imshow(‘Green plane image’, temp)
cv2.waitKey(0)

again take a zero matrix of image matrix shape

temp = np.zeros((row, col, plane), np.uint8)

store red plane contents or data of image matrix

to the corresponding plane(red) of temp matrix

temp[:, :, 2] = img[:, :, 2]

displaying the Red plane image

cv2.imshow(‘Red plane image’, temp)
cv2.waitKey(0)