gistfile1.txt

#!/usr/bin/env python3
import os
import subprocess
import json
import datetime

class ldict(dict):
        def __missing__(self, key):
                return 0

length = ldict()

def getlen(filename, category):
        global length
        foo = json.loads(subprocess.check_output(['avprobe', '-hide_banner', '-show_streams', '-print_format', 'json', filename], stderr=subprocess.DEVNULL).decode('UTF-8'))
        length[category] += float(foo['streams'][0]['duration'])

def traversedir(root, ext, fkt):
        for (dirpath, dirnames, filenames) in os.walk(root):
                for file in filenames:
                        file = os.path.join(dirpath, file)
                        if file.endswith(ext):
                                fkt(file, root)

def getdirs():
        return [dir for dir in os.listdir('.') if os.path.isdir(dir)]

for dir in getdirs():
        traversedir(dir, ('m2ts', 'MTS'), getlen)

for key in length:
        print('{} {}'.format(key, datetime.timedelta(seconds=int(length[key]))))