如何编码流音频？

Question

对不起，我的英语！

我需要将流音频编码为wav或ogg的文件。

这是流音频的和平：data：audio / ogg;编解码器= 0; base64，T2dnUwACAAAAAAAAAABABHGwAAAAAAANOrXmwBE09wdXNIZWFkAQE4AQDuAgAAAABPZ ...

 let mediaRecorder;
  navigator.mediaDevices.getUserMedia({audio:true})
  .then(stream =>{
      mediaRecorder = new MediaRecorder(stream);
      let partesAudio = []//se for longo ele salva em partes
      mediaRecorder.ondataavailable = data =>{
      partesAudio.push(data.data);
      }

  mediaRecorder.onstop=() =>{
      const blob = new Blob(partesAudio,{type:'audio/ogg; codecs=0'})
      const reader = new window.FileReader()
      reader.readAsDataURL(blob)


      reader.onloadend= async () =>{
      console.log(reader.result)
      var resultado= await  fetch('http://localhost:4000/fala/',{
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({
              fala:reader.result //'frase8.wav'
            }),
          });

在后端

const fs = require('fs');
fs.writeFileSync('something.ogg',req.body.fala)

我发现的唯一想法是想法，我怎么做却没有尝试的代码