Situation: unable to view .m4s files in Ubuntu 16.04   
Motivation: I recorded videos by Chrome's addon, GetThemAll, and get a result of 10 .mp4 videos     
Unsuccessful viewers/converters: vlc, http://online-audio-converter.com/, not .m4a files as described [here][1]     

Files in using GetThemAll, `ls -l directory` and `file *`. You see no pieces of information about any init file

    $ ls -la
    total 25148
    -rw-rw-r--  1 masi masi  1108289 Jul 26 21:09 segment-10.m4s.m4s
    -rw-rw-r--  1 masi masi   288300 Jul 26 21:09 segment-1.m4s(1).m4s
    -rw-rw-r--  1 masi masi   837663 Jul 26 21:09 segment-1.m4s.m4s
    -rw-rw-r--  1 masi masi   619611 Jul 26 21:09 segment-3.m4s.m4s
    -rw-rw-r--  1 masi masi  1495295 Jul 26 21:09 segment-4.m4s.m4s
    -rw-rw-r--  1 masi masi  1522196 Jul 26 21:09 segment-5.m4s.m4s
    -rw-rw-r--  1 masi masi  2205837 Jul 26 21:09 segment-6.m4s.m4s
    -rw-rw-r--  1 masi masi  2108392 Jul 26 21:09 segment-7.m4s.m4s
    -rw-rw-r--  1 masi masi  1937186 Jul 26 21:09 segment-8.m4s.m4s
    -rw-rw-r--  1 masi masi   734191 Jul 26 21:09 segment-9.m4s.m4s

    $ file *
    segment-10.m4s.m4s:                                                           data
    segment-1.m4s(1).m4s:                                                         data
    segment-1.m4s.m4s:                                                            data
    segment-3.m4s.m4s:                                                            data
    segment-4.m4s.m4s:                                                            data
    segment-5.m4s.m4s:                                                            data
    segment-6.m4s.m4s:                                                            data
    segment-7.m4s.m4s:                                                            data
    segment-8.m4s.m4s:                                                            data
    segment-9.m4s.m4s:                                                            data

I do unsuccessfully and try to open the .mp4 file in VLC without playing

    # andrew.46
    $ cat $(ls -x *.m4s) > testing.mp4
    
    $ file testing.mp4 
    testing.mp4: data
    

   - Output of `ls -x *.m4s`

        segment-10.m4s.m4s  segment-1.m4s(1).m4s  segment-1.m4s.m4s
        segment-3.m4s.m4s   segment-4.m4s.m4s     segment-5.m4s.m4s
        segment-6.m4s.m4s   segment-7.m4s.m4s     segment-8.m4s.m4s
        segment-9.m4s.m4s


Proposals

- http://stackoverflow.com/q/13682218/54964 > https://gpac.wp.mines-telecom.fr/player/ but `gpac` not in apt-get
- `cat init.mp4 file.m4s > file.mp4` as proposed [here][2] did not work. TODO how to get the initialisation segment? 

System: Ubuntu 16.04 64 bit   


  [1]: https://askubuntu.com/q/610156/25388
  [2]: http://stackoverflow.com/a/29175518/54964