Looking for advice on Replaygain

[nicholas_he]

I've read about Replaygain being useful for keeping volume levels consistent between different videos by setting the option for Replaygain to Track in the advanced settings. However some of the writing online indicates that the files obviously need to be analysed first. Does VLC do this on the fly, or do files need to be scanned first?

If VLC does it on the fly, is the volume metadata saved somewhere?

Also, can you override the volume adjustment for a specific file?

For background, I have a playlist of video files of short films that have annoyingly different sound levels, and I'm trying to get Replaygain to manage the volume instead of having to manually increase and decrease volume during the screenings.

Thanks VLC gurus!

[nicholas_he]

An update on this one. I've read that there are applications that scan media files and save the Replaygain value on the file, apps like foobar2000 on Windows, or Media Volume Pro on macOS. In theory that means that VLC would read those values and if enabled, manage the volume to achieve the desired volume level.

What I cannot work out, is, is the pre-scanning and saving files required to let VLC use the Replaygain values, or does it re-caculate this automatically?