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