I have some files Joapira___BERLINA_DEL_HIERRO.mp4Joapira___EL_BAILE_DEL_VIVO.mp4Joapira___EL_CONDE_CABRA.mp4Joapira___FLAIRE.mp4Joapira___MAZULKA_DEL_HIERRO.mp4Joapira___MEDA_A_MANOLITO_DIAZ_ARTESANO_TALLISTA.mp4that I want to convert to some other formats with ffmpeg and GNU parallel. For example to convert them to flac I doparallel --bar ffmpeg -i {} -map_metadata 0 {/.}.flac ::: *or to convert them to mp3 I doparallel --bar ffmpeg -i {} -vn -ar 44100 -ab 128k -map_metadata 0 {/.}.mp3 ::: $@but the process continues forever and the first file is always missing. Why?InfoI am on Fedora 22 usingGNU parallel 20160222andffmpeg version N-80953-gd4c8e93-static http://johnvansickle.com/ffmpeg/UpdateFascinating, I tried it with ffmpeg version 2.6.8 (comes with Fedora) and it works!! And even with the most recent static build from git it does not. :-(Update 2When I run ps auxwww and search for ffmpeg I see all the jobs with the state Rl, except for the command of the file that is missing, which has the state T.GNU parallel has the state S+, but sometimes during the processing of the working files changes to R+.The man page of ps says the following about the states:D    uninterruptible sleep (usually IO)R    running or runnable (on run queue)S    interruptible sleep (waiting for an event to complete)T    stopped by job control signalt    stopped by debugger during the tracingW    paging (not valid since the 2.6.xx kernel)X    dead (should never be seen)Z    defunct (zombie) process, terminated but not reaped by its parent<    high-priority (not nice to other users)N    low-priority (nice to other users)L    has pages locked into memory (for real-time and custom IO)s    is a session leaderl    is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)+    is in the foreground process groupMaybe this helps to understand the problem.
gnu parallel with ffmpeg does not process first file
shell script;ffmpeg;gnu parallel
Solution is as suggested by @OleTange in a comment to update to a newer version of parallel, i.e. GNU parallel 20161122. EVerything works again.And it is better to protect the commands from shell interaction with single quotes, i.e.:parallel --bar 'ffmpeg -i {} -map_metadata 0 {/.}.flac' ::: *andparallel --bar 'ffmpeg -i {} -vn -ar 44100 -ab 128k -map_metadata 0 {/.}.mp3' ::: $@