In a past article, I went over how to use a command-line utility called PACPL to extract audio from video files. Although the process was straight forward and effective back then, the program seems to be buggy at the time of writing and so I wanted to go over an alternative method. In this article we’ll be using the robust command-line program ffmpeg to achieve this.

ffmpeg is a very fast video and audio converter that can also grab from a live audio/video source. It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter. — FFMPEG manual

What you’ll need

• a working installation of ffmpeg
• terminal

Install ffmpeg

Most linux distributions ship with ffmpeg already installed but if you don’t have it installed, open up your terminal and type:

sudo apt install ffmpeg

Converting mp4 to mp3

To extract audio from a video source, open up your terminal and type the command below:

ffmpeg -i input-video.mp4 output-audio.mp3
# the input-video here represents your video source file 
# and the output-audio is the name of the audio file you want to output to. 
# Rename accordingly.

In case you want to convert the vide to a lossless format such as aac, simply replace the mp3 extension with a format of choice.

Let the process run and you should be able to have some audio output at the end of the conversion.

Cheers.