图像数组的维度是 3D 而不是 Python 课程中的二维

Question

In my python course, the instructor uploads a greyscale picture of himself and reads it on Python with the following code:

import numpy as np
import math
from PIL import Image
from IPython.display import display

im = Image.open("chris.tiff")
array = np.array(im)

print(array.shape)

and he gets

(200,200)

When I write the code and run my own image, with the exact same extension "tiff", I get a 3-dimensional array. I was told it's because my image was colored and so the third entry is for RBG. So I used a greyscale photo just like he did but I still obtain a 3D array, why?

Any help is greatly appreciated, thank you

EDIT

For extra clarity, the array I get for my greyscale image with tiff extension is

(3088, 2316, 4)

Answer 1

Your photo appears to be grey, but actually, it has the three channels based on the posted shape.

So, you need to convert it to greyscale using the following line:

im = Image.open("chris.tiff").convert('L')