跨网络套接字从麦克风流式传输音频。我可以看到正在发送的数据,但在接收客户端却听不到

时间:2019-07-06 22:37:37

标签: audio audiocontext

我正在尝试通过网络套接字广播捕获的麦克风音频。我可以看到正在发送缓冲区数组,并且该数组具有实际有效数据,但是接收方客户端无法听到它。我非常确定我的播放功能是正确的,因为我可以通过用随机数填充数组并使用播放功能来听到它来产生白噪声。我在想也许正在广播的音频太安静而无法听到,因为数组中生成的数字似乎大多在.000 ###范围内。有任何想法吗?捕获麦克风音频并进行广播似乎过于复杂...:/

 //broadcasting side 
  navigator.mediaDevices.getUserMedia({audio: true,video: false}) // request cam
        .then(stream => {
         vid.srcObject = stream;
         context = new AudioContext();
         var source = context.createMediaStreamSource(stream);
         var processor = context.createScriptProcessor(1024, 2, 2);
         source.connect(processor);
         processor.connect(context.destination);

         processor.onaudioprocess = function(e) {
           audiodata = e.inputBuffer.getChannelData(1);
          socket.send(JSON.stringify({sound: audiodata, to: to, from: '$username', text:''}));
         };
         return vid.play(); // returns a Promise
       });



//receiving side object to array 

       if(typeof (message.sound) != "undefined"){
         //$('#video_stream_btn').trigger('click');
          var json_sound = message.sound;
          var array_sound = [];
          for(var i in json_sound){
            array_sound.push([i, json_sound [i]]);
          }
         if(typeof(context) == 'undefined'){
           context = new AudioContext();
         }
         play_sound(array_sound, context);
         return;
       }


// receiving side play sound function 

    function play_sound(raw,context){

        //alert(raw.length);
        var audioBuffer = context.createBuffer(1, raw.length, context.sampleRate);
        audioBuffer.getChannelData(0).set(raw);
        var source = context.createBufferSource();
        source.buffer = audioBuffer;
        source.connect(context.destination);
        source.start(0);

    }

1 个答案:

答案 0 :(得分:0)

对于任何试图解决这个问题的人。我最终将其编码为int16array,然后通过套接字发送,客户端在客户端将其编码回float32数组,并将其传递给play_sound函数。我基本上只是从stackoverflow中偷了很多东西,然后伪造了它,直到我成功了,因为我不那么聪明:)

捕获麦克风并转换为int16array,然后通过套接字发送

 navigator.mediaDevices.getUserMedia({audio: {sampleSize: 16, channelCount: 2},video: true}) // request cam
        .then(stream => {
         vid.srcObject = stream; // don't use createObjectURL(MediaStream)
         context = new AudioContext();
         var source = context.createMediaStreamSource(stream);
         var processor = context.createScriptProcessor(1024, 2, 2);
         source.connect(processor);
         processor.connect(context.destination);

         processor.onaudioprocess = function(e) {
          // Do something with the data, i.e Convert this to WAV
          audiodata = new Int16Array(convertFloat32ToInt16(e.inputBuffer.getChannelData(0)));
          console.log(audiodata);
          socket.send(JSON.stringify({sound: audiodata, to: to, from: '$username', text:''}));

         };
         return vid.play(); // returns a Promise
       });

将捕获的麦克风转换为int16array的相关函数:

function convertFloat32ToInt16(buffer){
          l = buffer.length;
          buf = new Int16Array(l);

      while (l--)
      {
         buf[l] = Math.min(1, buffer[l])*0x7FFF;
      }

      return buf.buffer;

  }

将客户端json对象接收到int16array,然后将int16array返回给float32array:

if(typeof (message.sound) != "undefined"){
         //$('#video_stream_btn').trigger('click');
          //var json_sound = message.sound;


         if(typeof(context) == 'undefined'){
           context = new AudioContext();
         }
         sound_array = [];
         for (i in message.sound)
         {
            sound_array[i] = (message.sound [i]);
         }

        //sound_array16 = new Int16Array(sound_array);
        sound_array32 = int16ToFloat32(sound_array);
         play_sound(sound_array32, context);
         return;
       }

与float32array函数相关的接收方int16array:


    function int16ToFloat32(inputArray) {

        let int16arr = new Int16Array(inputArray)
        var output = new Float32Array(int16arr.length);
        for (var i = 0; i < int16arr.length; i++) {
            var int = int16arr[i];
            var float = (int >= 0x8000) ? -(0x10000 - int) / 0x8000 : int / 0x7FFF;
            output[i] = float;
        }
        return output;
    }