How to flip an image horizontally in python ?

Examples of how to flip an image horizontally in python:

Get a vertically flipped image using pillow

To flip an image horizontally a solution is to use the function mirror(), example:

from PIL import Image
from PIL import ImageOps

im = Image.open("lena.png")

im = ImageOps.mirror(im)

im.save("lena_mirror.png")
im.show()

Get a vertically flipped image using numpy

To flip an image horizontally with numpy there is fliplr, illustration:

import numpy as np 
import matplotlib.pyplot as plt
import matplotlib.image as mpimg

img = mpimg.imread('lena.png')

img2 = np.fliplr(img)
plt.imshow(img2)

plt.savefig("lena_mirror_matplotlib.png", dpi=200)
plt.show()

Note: to save an image with frameless see How to create a figure with no axes ( frameless ) or labels using matplotlib ?

References