PIL Image can not open transformed image with skimage.io - python

I have performed a shear and horizona flip transformations on an float array saved in a PFM file, then I have saved them as tif files through this code:
import os
from scipy import ndarray
# image processing library
import skimage as sk
from skimage.transform import warp
from skimage import util
from skimage import io
import numpy as np
def shear(image_array: ndarray, shear=10):
tf_augment = sk.transform.AffineTransform(shear=np.deg2rad(shear))
return warp(image_array, tf_augment, order=1, preserve_range=True,
mode='edge')
def horizontal_flip(image_array: ndarray):
return image_array[:, ::-1]
image_path='./train/0006.pfm'
image_to_transform, scale=readPFM(image_path)
flipped_image1=horizontal_flip(image_to_transform)
io.imsave("flipped_image1.tif", flipped_image1)
sheared_image1 =shear(image_to_transform,5)
io.imsave("sheared_image1.tif", sheared_image1)
However, when I try to open these images with PIL framework, it works with the flipped image but not with sheared one:
from PIL import Image
Image.open("sheared_image1.tif")
I got the error
OSError: cannot identify image file 'sheared_image1.tif'
Could anyone explain to me the reason, or how to save my transformed images through skimage framework to be able to read them with PIL (I have to read them with PIL for latter purposes)

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