import os

import argparse

import time

import cv2

from os.path import join, getmtime

def get_image_size(path):

    img = cv2.imread(path)

    height, width, _ = img.shape

    return (width, height)

def generate_video(output, frames, size, fps):

    out = cv2.VideoWriter(

        args.output, cv2.VideoWriter_fourcc(*'DIVX'), args.fps, size)

    for frame in frames:

        img = cv2.imread(frame)

        out.write(img)

    out.release()

def main(args):

    # Load input frames, sorted by creation time.

    files = [join(args.input, f) for f in os.listdir(

        args.input) if os.path.isfile(join(args.input, f))]

    files.sort(key=lambda x: getmtime(x))

    print('Generating video...')

    print(f'Frame count: {len(files)}')

    start = time.time()

    generate_video(args.output, files, get_image_size(files[0]), args.fps)

    print(

        f'Output file {args.output} generated in {time.time() - start} seconds.')

if __name__ == "__main__":

    parser = argparse.ArgumentParser()

    parser.add_argument(

        "-i", "--input", help="path to a directory containing all frames")

    parser.add_argument(

        "-o", "--output", help="avi output file path", default="video.avi")

    parser.add_argument("-f", "--fps", type=int, help="frames per second", default=8)

    args = parser.parse_args()

    main(args)