thumb.py

import subprocess
import sys

"""
get single frame at specific time
=================================

ffmpeg -i "input.mp4" -ss <time> -vframes 1 single.png

get file length in seconds
==========================

ffprobe -i "input.mp4" -show_format 2>&1 | sed -n 's/duration=//p'

"""
def generate_gif():
    subprocess.run(["ffmpeg",
    "-f", "image2",
    "-framerate", "1",
    "-i", "thumb_%02d.jpg",
    "thumb.gif"])

def generate_thumbs(filename, thumbs=10, padding=0.1):

    seconds = get_length_in_seconds(filename)

    first = int(seconds * padding * 0.5)
    interval = int(seconds/thumbs)
    frames = range(first,int(seconds),interval)
    counter = 1
    for frame in frames:
        subprocess.run(["ffmpeg",
            "-ss", str(frame),
            "-i", filename,
            "-vframes", "1", 
            "thumb_{:02d}.jpg".format(counter)
        ])
        counter += 1

def get_length_in_seconds(filename):

    probe = subprocess.Popen(('ffprobe', '-i', filename, '-show_format'), stdout=subprocess.PIPE)
    output = subprocess.check_output(('sed', '-n', 's/duration=//p'), stdin=probe.stdout, universal_newlines=True)
    probe.wait()
    return float(output)


if __name__ == "__main__":
    filename = sys.argv[1]
    generate_thumbs(filename)
    generate_gif()