ffmpeg.py

import os
import sys
import subprocess
import re

HHMMSS_regex = re.compile(r"[0-9]{2}:[0-5][0-9]:[0-5][0-9]") # 00:00:00 - 99:59:59
MMSS_regex = re.compile(r"^[0-5][0-9]:[0-5][0-9]") # 00:00 - 59:59

def time_to_seconds(time: str) -> int:
    h, m, s = time.split(":")
    return int(h) * 3600 + int(m) * 60 + int(s)

def seconds_to_time(seconds: int) -> str:
    m, s = divmod(seconds, 60)
    h, m = divmod(m, 60)

    return f"{h:02d}:{m:02d}:{s:02d}"

def main(args):
    if (len(args) < 2):
        print("[error] No file given")
        return -1

    filepath = args[1]

    path = os.path.dirname(filepath)

    filename = os.path.basename(filepath)
    filename, ext = os.path.splitext(filename)

    out_filepath = os.path.join(path, f"ffmpeg_{filename}{ext}")
    print(out_filepath)

    start = input("Enter start time (MM:SS) or leave blank to start at 00:00: ")

    if (not start): # start at 00:00:00
        start = "00:00:00"
    elif (not HHMMSS_regex.match(start) and MMSS_regex.match(start)): # if its XX:XX not XX:XX:XX, add 00: as hours
        start = f"00:{start}"
    else:
        print(f"[error] '{start}' start time is invalid") # invalid time
        return -1

    print(f"starting at '{start}'")

    end = input("Enter end time (MM:SS) or leave blank to record to end: ")

    if (not end): # start at 00:00:00
        end = "00:00:00"
    elif (not HHMMSS_regex.match(end) and MMSS_regex.match(end)): # if its XX:XX not XX:XX:XX, add 00: as hours
        end = f"00:{end}"
    else:
        print(f"[error] '{end}' end time is invalid") # invalid time
        return -1

    try:
        start_seconds = time_to_seconds(start)

        record_args = f"-ss {start}"

        if (end):
            end_seconds = time_to_seconds(end)
            diff = end_seconds - start_seconds

            if (diff <= 0):
                print(f"[error] Start time '{start}' is after end time '{end}'")
                return -1

            end_str = seconds_to_time(diff)
            record_args += f" -t {end_str}" # add record time argument
    except Exception as e:
        print("[error] Invalid time given", e)
        return -1

    cmd_args = f"ffmpeg {record_args} -i \"{filepath}\" -c:v libx264 -crf 18 -preset slow -c:a aac -movflags +faststart \"{out_filepath}\""

    subprocess.call(cmd_args)

    return 0

if __name__ == "__main__":
    error_code = main(sys.argv)

    if (error_code < 0):
        input()
    else:
        input("done")