用python制作一个黑白文件夹

Question

I have a folder of JPEGs. They are all RGB. I want to convert them all to greyscale with scikit-image.

import glob
from skimage.color import rgb2gray
from skimage.io import imread, imsave
from skimage.filters import threshold_otsu
from skimage import img_as_uint
import os
from PIL import Image


list = os.chdir("C:/Users/Images/RGB")
for file in list:
    image1 = Image.open(file)
    image_converted = color.rgb2gray(image1)
    io.imsave("C:/Users/Images/Greyscale", image_converted)

I get the error message :

    AttributeError: 'JpegImageFile' object has no attribute 'ndim'

What am I doing wrongly here ?

Answer 1

Give this code a try:

from skimage import io, color
import os
import imghdr

source = r'C:\Users\Images\RGB'
destination = r'C:\Users\Images\Greyscale'

image_files = [os.path.join(root, filename) 
                   for root, dirs, files in os.walk(source) 
                   for filename in files 
                   if imghdr.what(os.path.join(root, filename))]

for fn in image_files:
    rgb = io.imread(fn)
    grey = color.rgb2gray(rgb)
    head, tail = os.path.split(fn)
    io.imsave(os.path.join(destination, tail), grey)

Notice that image_files is a list containing the full path name of all the image files found in source and its subdirectories (recursively). The complete list of image types being detected can be found at the documentation of the imghdr module.

Answer 2

It looks like you are not running the script in the directory the files are located.

Either use the full file path for Image.open(file) or os.chdir into "C:/Users/Images/RGB" .