Flutter -Adding Voice Effects to locally saved audio file(.m4a) - Change Pitch, Add Background Music, Change Voice

Question

I'm building a Flutter mobile application for Android. The User Should be able to add filters to the locally saved recorded audio file(.m4a) & should be able to play it after filters are applied. User Can apply filters like changing pitch, changing Voice, Mixing the audio by adding some background music. I don't find any library that supports these features. Anybody can suggest how to approach this ?

Solution

This can be achieved by using the Just Audio Library for Flutter
https://pub.dev/packages/just_audio.

Effects:.

This package offers different options to play with voice - Change Pitch, Equalizer, Loudness to add effects to the given local audio file / URL.

Background Music:.

To add background music, you can create another instance of a player & start playing some music of your choice while you are playing the main audio file.