Increase media volume with ffmpeg

It is easy to physically increase or decrease the volume of any video or audio file using ffmpeg.

ffmpeg -i <source-file> -vcodec copy -af "volume=10dB" <output-file>

where <source-file> is the source file which you want to increase by 10db and write to <output-file>. Note that increasing the volume significantly can have a negative impact on audio quality, specifically with loud noises, so it is best to experiment and see what works best.

If you are adjusting the volume in a large video file, you could experiment with just a 5-minute section of the source file, 10 minutes into the video:

ffmpeg -i <source-file> -ss 00:10:00 -t 300 -vcodec copy -af "volume=10dB" <output-file>