Question

我们已经构建了一个Web应用程序。该应用程序的核心是在网络上安排会议。因此，用户A（会议协调员）将安排会议/会话，而所有其他参与者B，C，D等将加入会议/会话。因此，我已经使用Twilio群组视频通话来实现它。

我有以下用例。我们要进行用户A（会议协调员）语音的音高转换。因此，所有其他参与者都将在组视频中接收变调的声音。我们已经分析了Twilio中的AWS Polly，但它与我们的用例不匹配。

所以请咨询一下Twilio中是否有任何服务可以实现这种情况。
（要么）是否可以打断Twilio的群呼并将音调改变的声音传递给其他参与者？

使用的示例代码

initAudio();

function initAudio() {

analyser1 = audioContext.createAnalyser();
analyser1.fftSize = 1024;
analyser2 = audioContext.createAnalyser();
analyser2.fftSize = 1024;

if (!navigator.getUserMedia)
    navigator.getUserMedia = navigator.webkitGetUserMedia || navigator.mozGetUserMedia;

if (!navigator.getUserMedia)
    return(alert("Error: getUserMedia not supported!"));

navigator.getUserMedia({ audio: true }, function(stream){
    gotStream(stream);
}, function(){ console.log('Error getting Microphone stream'); });

if ((typeof MediaStreamTrack === 'undefined')||(!MediaStreamTrack.getSources)){
    console.log("This browser does not support MediaStreamTrack, so doesn't support selecting sources.\n\nTry Chrome Canary.");
} else {
    MediaStreamTrack.getSources(gotSources);
}
}
function gotStream (stream) {
audioInput = audioContext.createMediaStreamSource(stream);
outputMix = audioContext.createGain();
dryGain = audioContext.createGain();
wetGain = audioContext.createGain();
effectInput = audioContext.createGain();
audioInput.connect(dryGain);
audioInput.connect(effectInput);
dryGain.connect(outputMix);
wetGain.connect(outputMix);
audioOutput = audioContext.createMediaStreamDestination();
outputMix.connect(audioOutput);
outputMix.connect(analyser2);
crossfade(1.0);
changeEffect();
}
    function crossfade (value) {
        var gain1 = Math.cos(value * 0.5 * Math.PI);
        var gain2 = Math.cos((1.0 - value) * 0.5 * Math.PI);

    dryGain.gain.value = gain1;
    wetGain.gain.value = gain2;
}

function createPitchShifter () {
    effect = new Jungle( audioContext );
    effect.output.connect( wetGain );
    effect.setPitchOffset(1);
    return effect.input;
}

function changeEffect () {
    if (currentEffectNode)
        currentEffectNode.disconnect();
if (effectInput)
    effectInput.disconnect();

var effect = 'pitch';

switch (effect) {
    case 'pitch':
        currentEffectNode = createPitchShifter();
        break;
}

audioInput.connect(currentEffectNode);
}

在将Localaudiotrack添加到房间时遇到错误

var mediaStream = new Twilio.Video.LocalAudioTrack(audioOutput.stream);

room.localParticipant.publishTrack(mediaStream, {
    name: 'adminaudio'
});

错误： 未捕获（承诺）TypeError：无法在MediaStream上执行addTrack：参数1的类型不是MediaStreamTrack。

Answer 1

这里是Twilio开发人员的传播者。

Twilio本身没有音调会改变声音。

如果要在浏览器中进行构建，则可以使用Web Audio API从用户的麦克风获取输入并进行音高转换，然后将结果音频流而不是原始麦克风流提供给Video API。

Answer 2

以上答案中的评论很有帮助！我已经研究了几个星期，发布到 Twilio-video.js 无济于事，最后恰到好处的措辞在 S.O 上提出了这个！

但总结并添加我发现的工作，因为很难遵循所有 27 个问题/评论/代码摘录：

连接到 Twilio 时：

const room = await Video.connect(twilioToken, {
          name: roomName,
          tracks: localTracks,
          audio: false, // if you don't want to hear the normal voice at all, you can hide this and add the shifted track upon participant connections 
          video: true,
          logLevel: "debug",
        }).then((room) => {
          
          return room;
        });

在新的（远程）参与者连接上：

        const stream = new MediaStream([audioTrack.mediaStreamTrack]);
        const audioContext = new AudioContext(); 
        const audioInput = audioContext.createMediaStreamSource(stream);

source.disconnect(audioOutput);
          console.log("using PitchShift.js");
          var pitchShift = PitchShift(audioContext);

          if (isFinite(pitchVal)) {
            pitchShift.transpose = pitchVal;
            console.log("gain is " + pitchVal);
          }
          pitchShift.wet.value = 1;
          pitchShift.dry.value = 0.5;

          try {
            audioOutput.stream.getAudioTracks()[0]?.applyConstraints({
              echoCancellation: true,
              noiseSuppression: true,
            });
          } catch (e) {
            console.log("tried to constrain audio track " + e);
          }

          var biquadFilter = audioContext.createBiquadFilter();
          // Create a compressor node
          var compressor = audioContext.createDynamicsCompressor();
          compressor.threshold.setValueAtTime(-50, audioContext.currentTime);
          compressor.knee.setValueAtTime(40, audioContext.currentTime);
          compressor.ratio.setValueAtTime(12, audioContext.currentTime);
          compressor.attack.setValueAtTime(0, audioContext.currentTime);
          compressor.release.setValueAtTime(0.25, audioContext.currentTime);
          //biquadFilter.type = "lowpass";
          if (isFinite(freqVal)) {
            biquadFilter.frequency.value = freqVal;
            console.log("gain is " + freqVal);
          }
          if (isFinite(gainVal)) {
            biquadFilter.gain.value = gainVal;
            console.log("gain is " + gainVal);
          }
          source.connect(compressor);
          compressor.connect(biquadFilter);
          biquadFilter.connect(pitchShift);
          pitchShift.connect(audioOutput);
   
        const localAudioWarpedTracks = new Video.LocalAudioTrack(audioOutput.stream.getAudioTracks()[0]);

        const audioElement2 = document.createElement("audio");
        document.getElementById("audio_div").appendChild(audioElement2);

        localAudioWarpedTracks.attach();

Twilio集团视频中是否可以进行音高转换？

2 个答案: