I have a collection of videos, in the .mkv
and .mp4
(AAC+H.264) formats. The .mkv
files are ok, but all the .mp4
files have such a low volume that I can hardly hear it on my phone, even when volume is maxed.
I convert them using avconv
so they're smaller for my phone. It works fine, but I have not yet found out how I can normalize the volume on all the .mp4
files so they match the .mkv
files.
Just raising the volume alone would be a great achievement.
I've just been searching for a similar problem and used this solution from SuperUser
Basically, just extract the audio from the file as wav, run normalize-audio on it and then re-encode it as aac and remux.
I just wrote this quick script to do it:
Put it in a file like
normalize.sh
, then runbash normalize.sh file_to_convert.mp4
. You'll get a file outfile_to_convert-fixed.mp4
.You might want to tweak the
normalize-audio
command to just raise the volume by some dB with the-g
siwtch, or use another command entirely. I saw aacgain and wavegain mentioned elsewhere.normalize-audio
is in the package normalize-audio, funnily enough.Hope this helps you.
In OpenShot you can increase the volume of a video by 150%.