a little something i whipped up for cleaner Pyninsula recording cuts

mp4_cut.py

#!/usr/bin/env python
"""
./cut_mp4.py --input input.mp4 --start 00:00:01 --end 00:00:02 --no-align-keyframes --output output.mp4
"""

import os
import sys
import argparse
import datetime
import subprocess

FFMPEG_CMD = 'ffmpeg'
TIME_FORMAT = '%H:%M:%S'


def main(argv):
    prs = argparse.ArgumentParser()
    add_arg = prs.add_argument
    add_arg('--input', required=True)
    add_arg('--start')
    add_arg('--end')
    add_arg('--no-align-keyframes', action="store_true")  # TODO
    add_arg('--output', required=True)

    args = prs.parse_args()

    start_ts = args.start or '00:00:00'
    start_dt = datetime.datetime.strptime(start_ts, TIME_FORMAT)

    end_ts = args.end or '99:99:99'  # TODO
    end_dt = datetime.datetime.strptime(end_ts, TIME_FORMAT)

    assert end_dt > start_dt
    duration_ts = str(end_dt - start_dt)

    cmd = [FFMPEG_CMD, '-ss', start_ts, '-noaccurate_seek', '-i', args.input,
           '-vcodec', 'copy', '-acodec', 'copy', '-t', duration_ts,
           '-avoid_negative_ts', 'make_zero', args.output]

    return subprocess.check_call(cmd)


if __name__ == '__main__':
    sys.exit(main(sys.argv))