【Python】 Reading, writing and displaying images

 # We don't need to do this again, but it's a good habit

import cv2 

# Load an image using 'imread' specifying the path to image

input = cv2.imread('./images/input.png')

# Our file 'input.jpg' is now loaded and stored in python 

# as a varaible we named 'image'

# To display our image variable, we use 'imshow'

# The first parameter will be title shown on image window

# The second parameter is the image varialbe

cv2.imshow('Hello World', input)

# 'waitKey' allows us to input information when a image window is open# By leaving it blank it just waits for anykey to be pressed before 

# continuing. By placing numbers (except 0), we can specify a delay for# how long you keep the window open (time is in milliseconds here)

cv2.waitKey()

# This closes all open windows 

# Failure to place this will cause your program to hang

cv2.destroyAllWindows()

# Simply use 'imwrite' specificing the file name and the image to be saved

cv2.imwrite('output.jpg', input)

cv2.imwrite('output.png', input)