Web Audio API -如何将音频缓冲区保存到包含所有更改的文件中？

const audioContext = new AudioContext();

const audioSource = audioContext.createBufferSource();

const request = new XMLHttpRequest();
request.open('GET', 'audio_file.mp3', true);
request.responseType = 'arraybuffer';

request.onload = function() {
  const audioData = request.response;

  audioContext.decodeAudioData(audioData, function(buffer) {
    audioSource.buffer = buffer;
  });
};

request.send();

const gainNode = audioContext.createGain();
audioSource.connect(gainNode);

gainNode.connect(audioContext.destination);

audioSource.start();

const exportedBuffer = audioContext.createBuffer(1, audioSource.buffer.length, audioContext.sampleRate);
exportedBuffer.copyToChannel(audioSource.buffer.getChannelData(0), 0);

const audioBlob = bufferToWave(exportedBuffer);

function bufferToWave(abuffer) {
  const interleaved = interleave(abuffer.getChannelData(0));
  const dataview = encodeWAV(interleaved);
  const audioBlob = new Blob([dataview], { type: 'audio/wav' });
  return audioBlob;
}

function interleave(input) {
  const bufferLength = input.length;
  const output = new Float32Array(bufferLength * 2);
  for (let i = 0; i < bufferLength; i++) {
    output[i * 2] = input[i];
    output[i * 2 + 1] = input[i];
  }
  return output;
}

function encodeWAV(samples) {
  const buffer = new ArrayBuffer(44 + samples.length * 2);
  const view = new DataView(buffer);

  writeString(view, 0, 'RIFF');
  view.setUint32(4, 32 + samples.length * 2, true);
  writeString(view, 8, 'WAVE');
  writeString(view, 12, 'fmt ');
  view.setUint32(16, 16, true);
  view.setUint16(20, 1, true);
  view.setUint16(22, 2, true);
  view.setUint32(24, 44100, true);
  view.setUint32(28, 44100 * 4, true);
  view.setUint16(32, 4, true);
  view.setUint16(34, 16, true);
  writeString(view, 36, 'data');
  view.setUint32(40, samples.length * 2, true);

  floatTo16BitPCM(view, 44, samples);

  return view;
}

function writeString(view, offset, string) {
  for (let i = 0; i < string.length; i++) {
    view.setUint8(offset + i, string.charCodeAt(i));
  }
}

function floatTo16BitPCM(output, offset, input) {
  for (let i = 0; i < input.length; i++, offset += 2) {
    const s = Math.max(-1, Math.min(1, input[i]));
    output.setInt16(offset, s < 0 ? s * 0x8000 : s * 0x7FFF, true);
  }
}