Wrap ffmpeg to concat parts of a video file together using ffmpeg

ffmpeg_concat_cut.py

#!/usr/bin/env python3

import subprocess
from typing import Tuple
import tempfile
import argparse



def to_concat_input(from_to_seconds: Tuple[Tuple[int]], in_path: str) -> str:
    return "\n".join(
        [
            f"""file '{in_path}'
inpoint {from_sec}
outpoint {to_sec}"""
            for from_sec, to_sec in from_to_seconds
        ]
    )


def ffmpeg(from_to_seconds: Tuple[Tuple[int]], in_path: str, out_path: str):
    concat_path = tempfile.mktemp()
    concat_input = to_concat_input(from_to_seconds, in_path)
    with open(concat_path, "w") as f:
        f.write(concat_input)
    subprocess.Popen(f"ffmpeg -f concat -safe 0 -i {concat_path} -c copy {out_path}".split(), shell=False)


# requires ffmpeg
def main():
    parser = argparse.ArgumentParser("Wrap ffmpeg to concat parts of a video file together using ffmpeg.")
    parser.add_argument("-i", help="Input video path.")
    parser.add_argument("-o", help="Output video path.")
    parser.add_argument("from_to", help="start and endpoints in seconds to cut (must be sorted).", nargs="+", type=int)
    args= parser.parse_args()

    assert len(args.from_to) and len(args.from_to)  % 2== 0, "from_to must have a multiple of 2 arguments"
    assert sorted(args.from_to) == args.from_to, "from_to must be  ffmpeg to sorted"
    from_to = list(zip(*(args.from_to[::2], args.from_to[1::2])))
    ffmpeg(from_to, args.i, args.o)

if __name__ == "__main__":
    main()