Easily resize videos with ffmpeg

ffmpeg_helper.py

#! /usr/bin/env python3
"""
Video editing tools.

I don't remember the args for ffmpeg and it's useful to run them on multiple
videos in sequence. Great for shrinking game video that was captured at 4k.

Assumes ffmpeg is in your path. On Win10, use scoop to install (https://scoop.sh/).

Use .cmd files like this to make a drag-and-drop target:

@echo off

python3 C:\bin\ffmpeg_helper.py half_size %*

echo.
pause
"""

import subprocess
import sys
from pathlib import Path

preset_h264 = [
    "-c:v",
    "libx264",
    "-preset",
    "fast",
    "-crf",
    "26",
    "-c:a",
    "aac",
    "-b:a",
    "128k",
]


def _run_ffmpeg(args, suffix, files):
    """Convert input files to all be half-sized videos."""
    for src in files:
        src = Path(src)
        dest = src.with_stem(src.stem + suffix)

        cmd = ["ffmpeg", "-i", src] + args + [dest]

        print()
        print("Running:")
        print("  ", " ".join(str(s) for s in cmd))
        print()
        subprocess.check_call(cmd)


def half_size(*files):
    """Convert input files to all be half-sized videos."""
    cmd = [
        "-vf",
        "scale=w=iw/2:h=ih/2",
    ] + preset_h264
    _run_ffmpeg(cmd, "-small", files)


def to_1080(*files):
    """Convert input files to all be 1080p videos."""
    cmd = [
        "-vf",
        "scale=h=1080",
    ] + preset_h264
    _run_ffmpeg(cmd, "-1080p", files)


def to_h265(*files):
    """Convert input files to all be h265 with AAC.

    Xbox Game Bar produces massive files and this conversion reencodes to be
    smaller at the same quality.
    """
    # https://trac.ffmpeg.org/wiki/Encode/H.265
    cmd = [
        "-c:v",
        "libx265",
        "-crf",
        "26",
        "-preset",
        "fast",
        "-c:a",
        "aac",
        "-b:a",
        "128k",
        "-tag:v",
        "hvc1",
    ]
    _run_ffmpeg(cmd, "-h265", files)


def to_h264(*files):
    """Convert input files to all be h264 with AAC.

    Xbox Game Bar produces massive files and this conversion reencodes to be
    smaller at the same quality.
    """
    # https://trac.ffmpeg.org/wiki/Encode/H.264

    cmd = preset_h264
    _run_ffmpeg(cmd, "-h264", files)


if __name__ == "__main__":
    script_folder = Path(__file__).parent
    if script_folder not in sys.path:
        sys.path.insert(0, script_folder)
        print("Modified sys.path to add", script_folder)
    print(script_folder)
    args = sys.argv
    # args[0] = current file
    # args[1] = function name
    # args[2:] = function args : (*unpacked)
    globals()[args[1]](*args[2:])