I have a bunch of video files, and in some videos the sound is loud, in the others—not. So a user has to change the volume of her player when she watches these videos in the playlist. I want to level out the loudness in every video, so it's the same everywhere. How can I do it?
The videos contain human voices. All sound streams are in MPEG Layer-3 format. I will upload them on Youtube so playing with the settings of the player doesn't help.