Batch reencode video files with FFmpeg - version 1.0 - using python 3.9

iframe-steady.py

#!/usr/bin/env python3
#
# Batch file converter to reencode mp4 videos with a steady fixed i-frame interval (default to 25)
# 
# Tested under python 3.9.7
# Requires ffmpeg installed
# On Mac run 'brew install ffmpeg'
#
# You may need to give permission to this script
# $ chmod 700 ./iframe-steady.py
#
# Run this script from the same directory as your mp4 files
#
# e.g.
# $ ./iframe-steady.py
#
# This is main ffmpeg command run
# ffmpeg -i input.mp4 -c:v libx264 -preset slow -crf 22 -g 25 -keyint_min 25 -sc_threshold 0 -c:a copy output.mp4
# 
# check for a new 'exported_videos' folder
#
# dalton@yousician.com
# Know issue your files shouldn't have spaces our `.` (periods) in the file names.
#

print ('Make i-frames steadier')

import os, sys

directory = '.'

def is_tool(name):
    """Check whether `name` is on PATH and marked as executable."""
    from shutil import which
    return which(name) is not None

# check if have ffmpeg
if is_tool('ffmpeg') == False:
    sys.exit ("ffmpeg not found! Run 'brew install ffmpeg' and run this script again")

# create a new folder named sequentially
try:
    i = 0
    new_folder = "exported_videos_%s"
    while os.path.exists(new_folder % i):
        i += 1
    new_folder = new_folder % i
    os.makedirs(new_folder)
except OSError as e:
    if e.errno != errno.EEXIST:
        raise

# for each mp4 files in the dir, runs ffmpeg and output to that new folder
for filename in os.listdir(directory):
    f = os.path.join(directory, filename)    
    if os.path.isfile(f):
        if (f.endswith('.mp4')):
            print(f + ' is a mp4 file')                        
            os.system(f'ffmpeg -i {f} -c:v libx264 -preset slow -crf 22 -g 25 -keyint_min 25 -sc_threshold 0 -c:a copy {new_folder}/{f.removeprefix("./")}')