FFmpeg CLI to convert a video file to an MP3 audio file

You can use ffmpeg to convert a video file to an MP3 audio file with a simple command. Here’s a straightforward example:

ffmpeg -i input_video.mp4 -vn -acodec libmp3lame -q:a 2 output_audio.mp3

Explanation of Options

• -i input_video.mp4: Specifies the input video file.
• -vn: Tells ffmpeg to ignore the video stream (extract only audio).
• -acodec libmp3lame: Sets the audio codec to libmp3lame, which is a common codec for MP3 encoding.
• -q:a 2: Controls the audio quality. Lower values give better quality (2 is typically very good; you can adjust from 0–9, with 0 being the best).
• output_audio.mp3: Specifies the output file name in MP3 format.

Example in Python

You can also use ffmpeg in Python via the subprocess module or with the ffmpeg-python library. Here’s an example using ffmpeg-python:

import ffmpeg

# Convert video to mp3
ffmpeg.input('input_video.mp4').output('output_audio.mp3', **{'vn': None, 'q:a': 2}).run()

This script will read input_video.mp4 and output output_audio.mp3 with the specified quality.