concat-videos.py

import sys
import os
import subprocess
import tempfile
from argparse import ArgumentParser


def generate_input_file(video_files: list[str]) -> str:
    with tempfile.NamedTemporaryFile(
        mode="w",
        delete=False,
        suffix=".txt",
    ) as temp_input_file:
        try:
            for video in video_files:
                temp_input_file.write(
                    f"file '{os.path.abspath(video)}'\n",
                )
            return temp_input_file.name
        except Exception as e:
            print(f"Error writing to temporary input file: {e}")
            sys.exit(1)


def concat_videos(video_files, output_file):
    # Generate temporary input file.
    input_file = generate_input_file(video_files)

    # Build ffmpeg command line.
    ffmpeg_command = [
        "ffmpeg",
        "-safe", "0",
        "-f", "concat",
        "-i", input_file,
        "-c", "copy",
        output_file
    ]

    try:
        subprocess.run(ffmpeg_command, check=True)
        print(f"Videos concatenated successfully into {output_file}")
    except subprocess.CalledProcessError as e:
        print(f"Error during ffmpeg execution: {e}")
        sys.exit(1)
    finally:
        if os.path.exists(input_file):
            os.remove(input_file)


def main():
    parser = ArgumentParser(description="Concatenate videos using ffmpeg.")
    parser.add_argument("videos", nargs="+",
                        help="List of videos to concatenate")
    parser.add_argument("-o", "--output", required=True,
                        help="Output video file name")
    args = parser.parse_args()

    for video in args.videos:
        if not os.path.exists(video):
            print(f"File not found: {video}")
            sys.exit(1)

    concat_videos(args.videos, args.output)


if __name__ == "__main__":
    main()