Record Audio using JavaScript and Output in Base64

recorder.js

let recorder = null;

const onsuccess = (stream) => {
    recorder = new MediaRecorder(stream, {
        type: 'audio/ogg; codecs=opus'
    });

    recorder.start(); // Starting the record

    recorder.ondataavailable = (e) => {
        // Converting audio blob to base64
        let reader = new FileReader()
        reader.onloadend = () => {
            console.log(reader.result);
            // You can upload the base64 to server here.
        }

        reader.readAsDataURL(e.data);
    }
}

navigator.getUserMedia = (
    navigator.getUserMedia ||
    navigator.webkitGetUserMedia ||
    navigator.mozGetUserMedia ||
    navigator.msGetUserMedia
);

navigator.getUserMedia({
    audio: true
}, onsuccess, (e) => {
    console.log(e);
});

setTimeout(() => {
    recorder.stop(); // Stopping the recorder after 3 seconds
}, 3000);

Hi, thank you so much for sharing this code. Is there any way we can increase the sound quality? or change the audio codec? and format? please guide