Converts all video files to H265, deleting the sources as well.

make_h265.py

import pathlib
import subprocess
import re

VIDEO_TYPES = [
    '.mp4',
    '.avi',
    '.mkv',
    '.mov',
    '.webm',
]

PARTIAL_PATTERN = re.compile('.+_x265_part$')
PROCESSED_PATTERN = re.compile('.+_x265$')

def partial_path(path: pathlib.Path):
    return path.with_stem(f'{path.stem}_x265_part').with_suffix('.mp4')

def processed_path(path: pathlib.Path):
    return path.with_stem(f'{path.stem}_x265').with_suffix('.mp4')

unprocessed_videos = [
    path for path in (pathlib.Path.cwd() / 'Takeout').rglob('*')
    if path.is_file
    and path.suffix.lower() in VIDEO_TYPES
    and not PARTIAL_PATTERN.match(path.stem)
    and not PROCESSED_PATTERN.match(path.stem)
    and not processed_path(path).exists()
]

for idx, video_path in enumerate(unprocessed_videos):
    print(f'\n\n>> Starting video #{idx+1} of {len(unprocessed_videos)}: {video_path}')
    video_partial_path = partial_path(video_path)

    if video_partial_path.exists():
        print(f'>>>> Found partial video: {video_partial_path}')
        video_partial_path.unlink()

    command = [
        'ffmpeg', '-xerror', '-hide_banner',
        # '-loglevel', 'error',
        '-i', video_path,
        '-map_metadata', '0',
        '-c:a', 'libopus', '-b:a', '64k',
        '-c:v', 'libx265', '-preset', 'veryfast', '-x265-params', 'log-level=error:crf=23',
        '-c:s', 'copy',
        video_partial_path,
    ]
    subprocess.run(command, check=True)

    video_processed_path = processed_path(video_path)
    video_partial_path.rename(video_processed_path)
    video_path.unlink()

    print(f'>> Processed video #{idx+1} of {len(unprocessed_videos)}: {video_processed_path}')