You will need to install ffmpeg on your linux machine and then use terminal
ffmpeg -ss 00:00 -i Tube-4x-speed.m4v -t 00:01 Tube-4x-speed_%03d.png
-ss represents the start time
-t represents the time duration
-i for the input file
%03d represents the sequence number being added to the end of the file for each frame. 3 decimal places