Convert image format from jp2k to jpeg

convert.py

""" Convert jp2k image to jpeg.

# Install JPEG2k decoder first
sudo yum install -y libjpeg-devel
"""
import os
import argparse
from pathlib import Path

import cv2


def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('--input-file', required=True, help='Input image')
    parser.add_argument('--output-root', required=True, help='Output root directory')
    args = parser.parse_args()

    return args

def main():
    args = parse_args()

    # open image
    img = cv2.imread(args.input_file)
    h, w, c = img.shape

    # resize image
    max_length = 1920    # book domain default max length
    if w >= h:
        new_w = max_length
        new_h = int(h * (max_length / w))
    else:
        new_w = int(w * (max_length / h))
        new_h = max_length

    new_img = cv2.resize(img, dsize=(new_w, new_h), interpolation=cv2.INTER_AREA)

    # save image
    output_filepath = Path(args.output_root) / Path(args.input_file).with_suffix('.jpg')
    print(output_filepath)
    output_dir = output_filepath.parents[0]
    os.makedirs(output_dir, exist_ok=True)

    cv2.imwrite(output_filepath.as_posix(), new_img)

if __name__ == '__main__':
    main()