Reduce image channels in python

Question

I have an image with dimension of (128, 19, 3), i want to convert it to (128, 19, 1). I used this code (in python) but it converts the image size to (128, 19) not (128, 19, 1) which i want. thanks if anyone can help

from PIL import Image
import glob
images = glob.glob('D:\\thesis\\Paper 3\\Feature 
Extraction\\two_dimension_Feature_extraction\\stft_feature\\Training_set\\P300\\*.png')
img = Image.open(images[0]).convert('L')

Answer 1

只需在数组末尾添加一个维度：

img = img[...,None]