Useful CLI commands
Video to MP3
This command extracts the audio from a video file and puts it in a MP3 file. Ffmpeg automatically works out the right codecs to use from the output file extention, in this case it's MP3.
ffmpeg -i VIDEOFILE OUTPUTFILE.mp3
If you wish to do the same with ann OGG file, you have to specificy that you want audio only, you can do this with the -vn argument.
ffmpeg -i VIDEOFILE -vn OUTPUTFILE.ogg
Strip JPEG metadata
For this command, you'll require a program called exiftool.
On Ubuntu-based distros: sudo apt install libimage-exiftool-perl
On Arch-based distros: sudo pacman -S perl-image-exiftool
Then use the following command to strip the metadata. INPUTFILE can include *.* or *.jpg as well as a specified file. The origional, unmodified files will be renamed and not overwritten.
exiftool -all= INPUTFILE