to convert videos in a folder to MP4 and remove the old file if successful, say "python transcode-to-mp4.py FOLDER --delete"

transcode-to-mp4.py

import os
import sys
from os import chdir, walk
from os.path import dirname, getsize, join
from pathlib import Path
from shutil import move

import ffmpeg
import filetype


def convert_video(input_file, output_file):
    (
        ffmpeg
        .input(input_file)
        .output(output_file)
        .overwrite_output()
        .run()
    )


def replace_extension_with_mp4(filename):
    # Split the filename into the name and the extension
    name, _ = os.path.splitext(filename)
    # Add .mp4 as the new extension
    new_filename = name + '.mp4'
    return new_filename


def get_extension(filename):
    # Split the filename into the name and the extension
    name, _ = os.path.splitext(filename)
    return _


def sizeof_fmt(num, suffix="B"):
    for unit in ["", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi"]:
        if abs(num) < 1024.0:
            return f"{num:3.1f}{unit}{suffix}"
        num /= 1024.0
    return f"{num:.1f}Yi{suffix}"


def main():
    # The top argument for walk
    topdir = sys.argv[1]
    chdir(topdir)
    total_bytes = 0
    for root, dirs, files in walk('.'):
        for name in files:
            if Path(join(root, name)).is_symlink():
                continue
            elif filetype.is_video(join(root, name)):
                if get_extension(name) == ".mp4":
                    continue
                size = getsize(join(root, name))
                total_bytes = size+total_bytes
                rename = replace_extension_with_mp4(name)
                dest = Path(join(topdir, root.strip('./'), rename))
                print("Transcoding:", join(root, name), sizeof_fmt(size), "->", dest)
                try:
                    # parent = Path(dirname(dest))
                    # parent.mkdir(parents=True, exist_ok=True)
                    convert_video(join(topdir, root, name), dest.as_posix())
                    if len(sys.argv) > 2 and sys.argv[2] == "--delete":
                        os.remove(join(topdir, root, name))
                except Exception:
                    raise
            else:
                pass
    print("Total:", sizeof_fmt(total_bytes))


if __name__ == '__main__':
    main()