Utility for batch modifying images

fix.py

import sys, os
import numpy as np
import imageio
from absl import app, flags
from tqdm import tqdm

opts = flags.FLAGS
flags.DEFINE_string('input_dir', 'masks', 'Input directory')
flags.DEFINE_string('output_dir', 'results', 'Outut directory')

to8b = lambda x: (255 * np.clip(x, 0, 1)).astype(np.uint8)

def process(img):
    # e.g. closing for a binary mask
    from skimage.color import rgb2gray
    from skimage.morphology import disk, closing
    return closing(rgb2gray(img), disk(5))[..., None].repeat(3, axis=-1)

def rename(in_file):
    # e.g. re-numbering to a 1-indexed naming
    number = int(in_file.split('.')[0])
    return '{:04d}.png'.format(number + 1)

def main(_):
    os.makedirs(opts.output_dir, exist_ok=True)
    in_files = [f for f in os.listdir(opts.input_dir) if f.endswith('.png')]
    for in_file in tqdm(in_files):
        img = imageio.imread(os.path.join(opts.input_dir, in_file))
        img = process(img)
        imageio.imwrite(
            os.path.join(opts.output_dir, rename(in_file)),
            to8b(img)
        )

if __name__ == "__main__":
    app.run(main)