preprocessing_scripts/preprocess_wss4luad.py

import numpy as np
from PIL import Image
import os

source_directory = '/home/ubuntu/thesis/data/WSSS4LUAD/2.validation/mask/'
output_directory = '/home/ubuntu/thesis/data/WSSS4LUAD/2.validation/masks_relabeled/'

dir_list = os.listdir(source_directory)
for d in dir_list:
    arr = np.array(Image.open(source_directory + d))
    arr[arr == 3] = 255
    arr = arr + 1
    Image.fromarray(arr).save(output_directory + d)