mp4cat.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
'''
Concatenate MP4 files

usage: mp4cat.py [-h] [-o OUTPUT] [-t TMPDIR] [-d] filename [filename ...]

positional arguments:
  filename              MP4 files to be concatenated

optional arguments:
  -h, --help            show this help message and exit
  -o OUTPUT, --output OUTPUT
                        output file name (default: out.mp4)
  -t TMPDIR, --tmpdir TMPDIR
                        temporay directory (deafult: /tmp)
  -k, --keep-tempfile   do not remove temporary file(s)
'''
import os, os.path, argparse, re, time
from subprocess import getoutput, check_call
from tempfile   import gettempdir, gettempprefix

def get_args():
    dofile  = 'out.mp4'
    dtmpdir = gettempdir()

    parser = argparse.ArgumentParser(description='Concatenate MP4 files')
    parser.add_argument('filename',
                        help='MP4 files to be concatenated',
                        nargs='+')
    parser.add_argument('-o', '--output',
                        help='output file name (default: {})'.format(dofile),
                        default=dofile)
    parser.add_argument('-t', '--tmpdir',
                        help='temporay directory (deafult: {})'.format(dtmpdir),
                        default=dtmpdir)
    parser.add_argument('-k', '--keep-tempfile',
                        help='do not remove temporary file(s)',
                        action='store_true')
    args = parser.parse_args()

    if os.path.exists(args.output):
        raise SystemExit('ERROR: Output file name already exists.')
    if len(args.filename) < 2:
        raise SystemExit('ERROR: Specified only a single file.')

    return (args)

def get_duration(ifile):
    slist = []

    print(ifile)
    if os.path.exists(ifile):
        finfo = getoutput('MP4Box -info "' + ifile + '"')
        dlist = re.findall(r'(Track # \d+) .* Duration (\d+:\d{2}:\d{2}\.\d{3})', finfo)
    else:
        raise SystemExit('ERROR: File not found.')

    for tr, d in dlist:
        h, m, s = d.split(':')
        sec = int(h) * 3600 + int(m) * 60 + float(s)
        print (tr, sec)
        slist.append(sec)

    return min(slist)

def main():
    tmprefix = "{}.{}".format(gettempprefix(), time.time())
    tlist    = []

    args = get_args()

    for i in range(1, len(args.filename)):
        afile = args.filename[0] if i == 1 else "{}.{}.mp4".format(tmprefix, i - 1)
        dur   = get_duration(afile)
        nfile = "{}.{}.mp4".format(tmprefix, i)
        cmd   = ('MP4Box',
                 '-tmp', args.tmpdir,
                 '-new', nfile,
                 '-add', '{}:dur={}'.format(afile, dur),
                 '-cat', args.filename[i])
        print('-tmp {0[2]} -new {0[4]} -add {0[6]} -cat {0[8]}'.format(cmd))
        check_call(cmd)
        tlist.append(nfile)

    print('Renaming result file to "{}"...'.format(args.output))
    os.rename(tlist[-1], args.output)
    if not args.keep_tempfile:
        for t in tlist[:-1]:
            print('Removing templrary file {}...'.format(t))
            os.remove(t)

if __name__ == '__main__':
    main()